From 95f3901beb9c2bfe278277235ef8ce46690dba5e Mon Sep 17 00:00:00 2001 From: Jay Williams Date: Thu, 14 May 2015 20:44:45 -0500 Subject: Add !default flag to each sass variable --- Gruntfile.js | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/Gruntfile.js b/Gruntfile.js index c21bfeb6..d8dbc5a6 100644 --- a/Gruntfile.js +++ b/Gruntfile.js @@ -230,6 +230,10 @@ grunt.registerTask('build_scss', 'build a regular theme from scss', function(the // 10. replace bower and imports in build.scss .replace(/bootstrap\/less\//g, 'bootstrap-sass-official/assets/stylesheets/') .replace(/\.less/g, ''); + // 11. only assign variables if they haven't been previously set e.g. $var: #f00; > $var: #f00 !default; + if (/\/variables.less$/.test(lessFile)) { + out = out.replace(/^(\$.*);/gm, '$1 !default;'); + } var baseDirRegex = new RegExp("^" + convertBaseDir, "g"); var sassFile = lessFile.replace(baseDirRegex, '').replace(/\.less$/, '.scss').replace(/(bootswatch|variables)/, '_$1'); -- cgit v1.2.3 From faf169d9ff9e6cad3a1127d3fe3807639e4a2cb9 Mon Sep 17 00:00:00 2001 From: Jay Williams Date: Thu, 14 May 2015 20:45:26 -0500 Subject: Rebuild each _variable.scss with grunt --- cerulean/_variables.scss | 764 +++++++++++++++++++++++----------------------- cosmo/_variables.scss | 764 +++++++++++++++++++++++----------------------- custom/_variables.scss | 764 +++++++++++++++++++++++----------------------- cyborg/_variables.scss | 764 +++++++++++++++++++++++----------------------- darkly/_variables.scss | 764 +++++++++++++++++++++++----------------------- flatly/_variables.scss | 764 +++++++++++++++++++++++----------------------- journal/_variables.scss | 764 +++++++++++++++++++++++----------------------- lumen/_variables.scss | 764 +++++++++++++++++++++++----------------------- paper/_variables.scss | 764 +++++++++++++++++++++++----------------------- readable/_variables.scss | 764 +++++++++++++++++++++++----------------------- sandstone/_variables.scss | 764 +++++++++++++++++++++++----------------------- simplex/_variables.scss | 764 +++++++++++++++++++++++----------------------- slate/_variables.scss | 764 +++++++++++++++++++++++----------------------- spacelab/_variables.scss | 764 +++++++++++++++++++++++----------------------- superhero/_variables.scss | 764 +++++++++++++++++++++++----------------------- united/_variables.scss | 764 +++++++++++++++++++++++----------------------- yeti/_variables.scss | 764 +++++++++++++++++++++++----------------------- 17 files changed, 6494 insertions(+), 6494 deletions(-) diff --git a/cerulean/_variables.scss b/cerulean/_variables.scss index 3225a27a..def82cbb 100644 --- a/cerulean/_variables.scss +++ b/cerulean/_variables.scss @@ -7,18 +7,18 @@ // //## Gray and brand colors for use across Bootstrap. -$gray-base: #000; -$gray-darker: lighten($gray-base, 13.5%); // #222 -$gray-dark: lighten($gray-base, 20%); // #333 -$gray: lighten($gray-base, 33.5%); // #555 -$gray-light: lighten($gray-base, 60%); // #999 -$gray-lighter: lighten($gray-base, 93.5%); // #eee +$gray-base: #000 !default; +$gray-darker: lighten($gray-base, 13.5%) !default; // #222 +$gray-dark: lighten($gray-base, 20%) !default; // #333 +$gray: lighten($gray-base, 33.5%) !default; // #555 +$gray-light: lighten($gray-base, 60%) !default; // #999 +$gray-lighter: lighten($gray-base, 93.5%) !default; // #eee -$brand-primary: #2FA4E7; -$brand-success: #73A839; -$brand-info: #033C73; -$brand-warning: #DD5600; -$brand-danger: #C71C22; +$brand-primary: #2FA4E7 !default; +$brand-success: #73A839 !default; +$brand-info: #033C73 !default; +$brand-warning: #DD5600 !default; +$brand-danger: #C71C22 !default; //== Scaffolding @@ -26,49 +26,49 @@ $brand-danger: #C71C22; //## Settings for some of the most global styles. //** Background color for ``. -$body-bg: #fff; +$body-bg: #fff !default; //** Global text color on ``. -$text-color: $gray; +$text-color: $gray !default; //** Global textual link color. -$link-color: $brand-primary; +$link-color: $brand-primary !default; //** Link hover color set via `darken()` function. -$link-hover-color: darken($link-color, 15%); +$link-hover-color: darken($link-color, 15%) !default; //** Link hover decoration. -$link-hover-decoration: underline; +$link-hover-decoration: underline !default; //== Typography // //## Font, line-height, and color for body text, headings, and more. -$font-family-sans-serif: "Helvetica Neue", Helvetica, Arial, sans-serif; -$font-family-serif: Georgia, "Times New Roman", Times, serif; +$font-family-sans-serif: "Helvetica Neue", Helvetica, Arial, sans-serif !default; +$font-family-serif: Georgia, "Times New Roman", Times, serif !default; //** Default monospace fonts for ``, ``, and `
`.
-$font-family-monospace:   Menlo, Monaco, Consolas, "Courier New", monospace;
-$font-family-base:        $font-family-sans-serif;
+$font-family-monospace:   Menlo, Monaco, Consolas, "Courier New", monospace !default;
+$font-family-base:        $font-family-sans-serif !default;
 
-$font-size-base:          14px;
-$font-size-large:         ceil(($font-size-base * 1.25)); // ~18px
-$font-size-small:         ceil(($font-size-base * 0.85)); // ~12px
+$font-size-base:          14px !default;
+$font-size-large:         ceil(($font-size-base * 1.25)) !default; // ~18px
+$font-size-small:         ceil(($font-size-base * 0.85)) !default; // ~12px
 
-$font-size-h1:            floor(($font-size-base * 2.6)); // ~36px
-$font-size-h2:            floor(($font-size-base * 2.15)); // ~30px
-$font-size-h3:            ceil(($font-size-base * 1.7)); // ~24px
-$font-size-h4:            ceil(($font-size-base * 1.25)); // ~18px
-$font-size-h5:            $font-size-base;
-$font-size-h6:            ceil(($font-size-base * 0.85)); // ~12px
+$font-size-h1:            floor(($font-size-base * 2.6)) !default; // ~36px
+$font-size-h2:            floor(($font-size-base * 2.15)) !default; // ~30px
+$font-size-h3:            ceil(($font-size-base * 1.7)) !default; // ~24px
+$font-size-h4:            ceil(($font-size-base * 1.25)) !default; // ~18px
+$font-size-h5:            $font-size-base !default;
+$font-size-h6:            ceil(($font-size-base * 0.85)) !default; // ~12px
 
 //** Unit-less `line-height` for use in components like buttons.
-$line-height-base:        1.428571429; // 20/14
+$line-height-base:        1.428571429 !default; // 20/14
 //** Computed "line-height" (`font-size` * `line-height`) for use with `margin`, `padding`, etc.
-$line-height-computed:    floor(($font-size-base * $line-height-base)); // ~20px
+$line-height-computed:    floor(($font-size-base * $line-height-base)) !default; // ~20px
 
 //** By default, this inherits from the ``.
-$headings-font-family:    $font-family-base;
-$headings-font-weight:    500;
-$headings-line-height:    1.1;
-$headings-color:          #317EAC;
+$headings-font-family:    $font-family-base !default;
+$headings-font-weight:    500 !default;
+$headings-line-height:    1.1 !default;
+$headings-color:          #317EAC !default;
 
 
 //== Iconography
@@ -76,45 +76,45 @@ $headings-color:          #317EAC;
 //## Specify custom location and filename of the included Glyphicons icon font. Useful for those including Bootstrap via Bower.
 
 //** Load fonts from this directory.
-$icon-font-path:          "../fonts/";
+$icon-font-path:          "../fonts/" !default;
 //** File name for all font files.
-$icon-font-name:          "glyphicons-halflings-regular";
+$icon-font-name:          "glyphicons-halflings-regular" !default;
 //** Element ID within SVG icon file.
-$icon-font-svg-id:        "glyphicons_halflingsregular";
+$icon-font-svg-id:        "glyphicons_halflingsregular" !default;
 
 
 //== Components
 //
 //## Define common padding and border radius sizes and more. Values based on 14px text and 1.428 line-height (~20px to start).
 
-$padding-base-vertical:     8px;
-$padding-base-horizontal:   12px;
+$padding-base-vertical:     8px !default;
+$padding-base-horizontal:   12px !default;
 
-$padding-large-vertical:    14px;
-$padding-large-horizontal:  16px;
+$padding-large-vertical:    14px !default;
+$padding-large-horizontal:  16px !default;
 
-$padding-small-vertical:    5px;
-$padding-small-horizontal:  10px;
+$padding-small-vertical:    5px !default;
+$padding-small-horizontal:  10px !default;
 
-$padding-xs-vertical:       1px;
-$padding-xs-horizontal:     5px;
+$padding-xs-vertical:       1px !default;
+$padding-xs-horizontal:     5px !default;
 
-$line-height-large:         1.3333333; // extra decimals for Win 8.1 Chrome
-$line-height-small:         1.5;
+$line-height-large:         1.3333333 !default; // extra decimals for Win 8.1 Chrome
+$line-height-small:         1.5 !default;
 
-$border-radius-base:        4px;
-$border-radius-large:       6px;
-$border-radius-small:       3px;
+$border-radius-base:        4px !default;
+$border-radius-large:       6px !default;
+$border-radius-small:       3px !default;
 
 //** Global color for active items (e.g., navs or dropdowns).
-$component-active-color:    #fff;
+$component-active-color:    #fff !default;
 //** Global background color for active items (e.g., navs or dropdowns).
-$component-active-bg:       $brand-primary;
+$component-active-bg:       $brand-primary !default;
 
 //** Width of the `border` for generating carets that indicator dropdowns.
-$caret-width-base:          4px;
+$caret-width-base:          4px !default;
 //** Carets increase slightly in size for larger components.
-$caret-width-large:         5px;
+$caret-width-large:         5px !default;
 
 
 //== Tables
@@ -122,53 +122,53 @@ $caret-width-large:         5px;
 //## Customizes the `.table` component with basic values, each used across all table variations.
 
 //** Padding for ``s and ``s.
-$table-cell-padding:            8px;
+$table-cell-padding:            8px !default;
 //** Padding for cells in `.table-condensed`.
-$table-condensed-cell-padding:  5px;
+$table-condensed-cell-padding:  5px !default;
 
 //** Default background color used for all tables.
-$table-bg:                      transparent;
+$table-bg:                      transparent !default;
 //** Background color used for `.table-striped`.
-$table-bg-accent:               #f9f9f9;
+$table-bg-accent:               #f9f9f9 !default;
 //** Background color used for `.table-hover`.
-$table-bg-hover:                #f5f5f5;
-$table-bg-active:               $table-bg-hover;
+$table-bg-hover:                #f5f5f5 !default;
+$table-bg-active:               $table-bg-hover !default;
 
 //** Border color for table and cell borders.
-$table-border-color:            #ddd;
+$table-border-color:            #ddd !default;
 
 
 //== Buttons
 //
 //## For each of Bootstrap's buttons, define text, background and border color.
 
-$btn-font-weight:                normal;
+$btn-font-weight:                normal !default;
 
-$btn-default-color:              $text-color;
-$btn-default-bg:                 #fff;
-$btn-default-border:             rgba(0, 0, 0, 0.1);
+$btn-default-color:              $text-color !default;
+$btn-default-bg:                 #fff !default;
+$btn-default-border:             rgba(0, 0, 0, 0.1) !default;
 
-$btn-primary-color:              #fff;
-$btn-primary-bg:                 $brand-primary;
-$btn-primary-border:             $btn-primary-bg;
+$btn-primary-color:              #fff !default;
+$btn-primary-bg:                 $brand-primary !default;
+$btn-primary-border:             $btn-primary-bg !default;
 
-$btn-success-color:              #fff;
-$btn-success-bg:                 $brand-success;
-$btn-success-border:             $btn-success-bg;
+$btn-success-color:              #fff !default;
+$btn-success-bg:                 $brand-success !default;
+$btn-success-border:             $btn-success-bg !default;
 
-$btn-info-color:                 #fff;
-$btn-info-bg:                    $brand-info;
-$btn-info-border:                $btn-info-bg;
+$btn-info-color:                 #fff !default;
+$btn-info-bg:                    $brand-info !default;
+$btn-info-border:                $btn-info-bg !default;
 
-$btn-warning-color:              #fff;
-$btn-warning-bg:                 $brand-warning;
-$btn-warning-border:             $btn-warning-bg;
+$btn-warning-color:              #fff !default;
+$btn-warning-bg:                 $brand-warning !default;
+$btn-warning-border:             $btn-warning-bg !default;
 
-$btn-danger-color:               #fff;
-$btn-danger-bg:                  $brand-danger;
-$btn-danger-border:              $btn-danger-bg;
+$btn-danger-color:               #fff !default;
+$btn-danger-bg:                  $brand-danger !default;
+$btn-danger-border:              $btn-danger-bg !default;
 
-$btn-link-disabled-color:        $gray-light;
+$btn-link-disabled-color:        $gray-light !default;
 
 
 //== Forms
@@ -176,50 +176,50 @@ $btn-link-disabled-color:        $gray-light;
 //##
 
 //** `` background color
-$input-bg:                       #fff;
+$input-bg:                       #fff !default;
 //** `` background color
-$input-bg-disabled:              $gray-lighter;
+$input-bg-disabled:              $gray-lighter !default;
 
 //** Text color for ``s
-$input-color:                    $text-color;
+$input-color:                    $text-color !default;
 //** `` border color
-$input-border:                   #ccc;
+$input-border:                   #ccc !default;
 
 // TODO: Rename `$input-border-radius` to `$input-border-radius-base` in v4
 //** Default `.form-control` border radius
 // This has no effect on ``s in CSS.
-$input-border-radius:            $border-radius-base;
+$input-border-radius:            $border-radius-base !default;
 //** Large `.form-control` border radius
-$input-border-radius-large:      $border-radius-large;
+$input-border-radius-large:      $border-radius-large !default;
 //** Small `.form-control` border radius
-$input-border-radius-small:      $border-radius-small;
+$input-border-radius-small:      $border-radius-small !default;
 
 //** Border color for inputs on focus
-$input-border-focus:             #66afe9;
+$input-border-focus:             #66afe9 !default;
 
 //** Placeholder text color
-$input-color-placeholder:        $gray-light;
+$input-color-placeholder:        $gray-light !default;
 
 //** Default `.form-control` height
-$input-height-base:              ($line-height-computed + ($padding-base-vertical * 2) + 2);
+$input-height-base:              ($line-height-computed + ($padding-base-vertical * 2) + 2) !default;
 //** Large `.form-control` height
-$input-height-large:             (ceil($font-size-large * $line-height-large) + ($padding-large-vertical * 2) + 2);
+$input-height-large:             (ceil($font-size-large * $line-height-large) + ($padding-large-vertical * 2) + 2) !default;
 //** Small `.form-control` height
-$input-height-small:             (floor($font-size-small * $line-height-small) + ($padding-small-vertical * 2) + 2);
+$input-height-small:             (floor($font-size-small * $line-height-small) + ($padding-small-vertical * 2) + 2) !default;
 
 //** `.form-group` margin
-$form-group-margin-bottom:       15px;
+$form-group-margin-bottom:       15px !default;
 
-$legend-color:                   $text-color;
-$legend-border-color:            #e5e5e5;
+$legend-color:                   $text-color !default;
+$legend-border-color:            #e5e5e5 !default;
 
 //** Background color for textual input addons
-$input-group-addon-bg:           $gray-lighter;
+$input-group-addon-bg:           $gray-lighter !default;
 //** Border color for textual input addons
-$input-group-addon-border-color: $input-border;
+$input-group-addon-border-color: $input-border !default;
 
 //** Disabled cursor for form controls and buttons.
-$cursor-disabled:                not-allowed;
+$cursor-disabled:                not-allowed !default;
 
 
 //== Dropdowns
@@ -227,34 +227,34 @@ $cursor-disabled:                not-allowed;
 //## Dropdown menu container and contents.
 
 //** Background for the dropdown menu.
-$dropdown-bg:                    #fff;
+$dropdown-bg:                    #fff !default;
 //** Dropdown menu `border-color`.
-$dropdown-border:                rgba(0,0,0,.15);
+$dropdown-border:                rgba(0,0,0,.15) !default;
 //** Dropdown menu `border-color` **for IE8**.
-$dropdown-fallback-border:       #ccc;
+$dropdown-fallback-border:       #ccc !default;
 //** Divider color for between dropdown items.
-$dropdown-divider-bg:            #e5e5e5;
+$dropdown-divider-bg:            #e5e5e5 !default;
 
 //** Dropdown link text color.
-$dropdown-link-color:            $gray-dark;
+$dropdown-link-color:            $gray-dark !default;
 //** Hover color for dropdown links.
-$dropdown-link-hover-color:      #fff;
+$dropdown-link-hover-color:      #fff !default;
 //** Hover background for dropdown links.
-$dropdown-link-hover-bg:         $component-active-bg;
+$dropdown-link-hover-bg:         $component-active-bg !default;
 
 //** Active dropdown menu item text color.
-$dropdown-link-active-color:     #fff;
+$dropdown-link-active-color:     #fff !default;
 //** Active dropdown menu item background color.
-$dropdown-link-active-bg:        $component-active-bg;
+$dropdown-link-active-bg:        $component-active-bg !default;
 
 //** Disabled dropdown menu item background color.
-$dropdown-link-disabled-color:   $gray-light;
+$dropdown-link-disabled-color:   $gray-light !default;
 
 //** Text color for headers within dropdown menus.
-$dropdown-header-color:          $gray-light;
+$dropdown-header-color:          $gray-light !default;
 
 //** Deprecated `$dropdown-caret-color` as of v3.1.0
-$dropdown-caret-color:           #000;
+$dropdown-caret-color:           #000 !default;
 
 
 //-- Z-index master list
@@ -264,13 +264,13 @@ $dropdown-caret-color:           #000;
 //
 // Note: These variables are not generated into the Customizer.
 
-$zindex-navbar:            1000;
-$zindex-dropdown:          1000;
-$zindex-popover:           1060;
-$zindex-tooltip:           1070;
-$zindex-navbar-fixed:      1030;
-$zindex-modal-background:  1040;
-$zindex-modal:             1050;
+$zindex-navbar:            1000 !default;
+$zindex-dropdown:          1000 !default;
+$zindex-popover:           1060 !default;
+$zindex-tooltip:           1070 !default;
+$zindex-navbar-fixed:      1030 !default;
+$zindex-modal-background:  1040 !default;
+$zindex-modal:             1050 !default;
 
 
 //== Media queries breakpoints
@@ -279,37 +279,37 @@ $zindex-modal:             1050;
 
 // Extra small screen / phone
 //** Deprecated `$screen-xs` as of v3.0.1
-$screen-xs:                  480px;
+$screen-xs:                  480px !default;
 //** Deprecated `$screen-xs-min` as of v3.2.0
-$screen-xs-min:              $screen-xs;
+$screen-xs-min:              $screen-xs !default;
 //** Deprecated `$screen-phone` as of v3.0.1
-$screen-phone:               $screen-xs-min;
+$screen-phone:               $screen-xs-min !default;
 
 // Small screen / tablet
 //** Deprecated `$screen-sm` as of v3.0.1
-$screen-sm:                  768px;
-$screen-sm-min:              $screen-sm;
+$screen-sm:                  768px !default;
+$screen-sm-min:              $screen-sm !default;
 //** Deprecated `$screen-tablet` as of v3.0.1
-$screen-tablet:              $screen-sm-min;
+$screen-tablet:              $screen-sm-min !default;
 
 // Medium screen / desktop
 //** Deprecated `$screen-md` as of v3.0.1
-$screen-md:                  992px;
-$screen-md-min:              $screen-md;
+$screen-md:                  992px !default;
+$screen-md-min:              $screen-md !default;
 //** Deprecated `$screen-desktop` as of v3.0.1
-$screen-desktop:             $screen-md-min;
+$screen-desktop:             $screen-md-min !default;
 
 // Large screen / wide desktop
 //** Deprecated `$screen-lg` as of v3.0.1
-$screen-lg:                  1200px;
-$screen-lg-min:              $screen-lg;
+$screen-lg:                  1200px !default;
+$screen-lg-min:              $screen-lg !default;
 //** Deprecated `$screen-lg-desktop` as of v3.0.1
-$screen-lg-desktop:          $screen-lg-min;
+$screen-lg-desktop:          $screen-lg-min !default;
 
 // So media queries don't overlap when required, provide a maximum
-$screen-xs-max:              ($screen-sm-min - 1);
-$screen-sm-max:              ($screen-md-min - 1);
-$screen-md-max:              ($screen-lg-min - 1);
+$screen-xs-max:              ($screen-sm-min - 1) !default;
+$screen-sm-max:              ($screen-md-min - 1) !default;
+$screen-md-max:              ($screen-lg-min - 1) !default;
 
 
 //== Grid system
@@ -317,14 +317,14 @@ $screen-md-max:              ($screen-lg-min - 1);
 //## Define your custom responsive grid.
 
 //** Number of columns in the grid.
-$grid-columns:              12;
+$grid-columns:              12 !default;
 //** Padding between columns. Gets divided in half for the left and right.
-$grid-gutter-width:         30px;
+$grid-gutter-width:         30px !default;
 // Navbar collapse
 //** Point at which the navbar becomes uncollapsed.
-$grid-float-breakpoint:     $screen-sm-min;
+$grid-float-breakpoint:     $screen-sm-min !default;
 //** Point at which the navbar begins collapsing.
-$grid-float-breakpoint-max: ($grid-float-breakpoint - 1);
+$grid-float-breakpoint-max: ($grid-float-breakpoint - 1) !default;
 
 
 //== Container sizes
@@ -332,19 +332,19 @@ $grid-float-breakpoint-max: ($grid-float-breakpoint - 1);
 //## Define the maximum width of `.container` for different screen sizes.
 
 // Small screen / tablet
-$container-tablet:             (720px + $grid-gutter-width);
+$container-tablet:             (720px + $grid-gutter-width) !default;
 //** For `$screen-sm-min` and up.
-$container-sm:                 $container-tablet;
+$container-sm:                 $container-tablet !default;
 
 // Medium screen / desktop
-$container-desktop:            (940px + $grid-gutter-width);
+$container-desktop:            (940px + $grid-gutter-width) !default;
 //** For `$screen-md-min` and up.
-$container-md:                 $container-desktop;
+$container-md:                 $container-desktop !default;
 
 // Large screen / wide desktop
-$container-large-desktop:      (1140px + $grid-gutter-width);
+$container-large-desktop:      (1140px + $grid-gutter-width) !default;
 //** For `$screen-lg-min` and up.
-$container-lg:                 $container-large-desktop;
+$container-lg:                 $container-large-desktop !default;
 
 
 //== Navbar
@@ -352,61 +352,61 @@ $container-lg:                 $container-large-desktop;
 //##
 
 // Basics of a navbar
-$navbar-height:                    50px;
-$navbar-margin-bottom:             $line-height-computed;
-$navbar-border-radius:             $border-radius-base;
-$navbar-padding-horizontal:        floor(($grid-gutter-width / 2));
-$navbar-padding-vertical:          (($navbar-height - $line-height-computed) / 2);
-$navbar-collapse-max-height:       340px;
+$navbar-height:                    50px !default;
+$navbar-margin-bottom:             $line-height-computed !default;
+$navbar-border-radius:             $border-radius-base !default;
+$navbar-padding-horizontal:        floor(($grid-gutter-width / 2)) !default;
+$navbar-padding-vertical:          (($navbar-height - $line-height-computed) / 2) !default;
+$navbar-collapse-max-height:       340px !default;
 
-$navbar-default-color:             #ddd;
-$navbar-default-bg:                $brand-primary;
-$navbar-default-border:            darken($navbar-default-bg, 6.5%);
+$navbar-default-color:             #ddd !default;
+$navbar-default-bg:                $brand-primary !default;
+$navbar-default-border:            darken($navbar-default-bg, 6.5%) !default;
 
 // Navbar links
-$navbar-default-link-color:                #fff;
-$navbar-default-link-hover-color:          #fff;
-$navbar-default-link-hover-bg:             darken($navbar-default-bg, 10%);
-$navbar-default-link-active-color:         #fff;
-$navbar-default-link-active-bg:            darken($navbar-default-bg, 10%);
-$navbar-default-link-disabled-color:       #ddd;
-$navbar-default-link-disabled-bg:          transparent;
+$navbar-default-link-color:                #fff !default;
+$navbar-default-link-hover-color:          #fff !default;
+$navbar-default-link-hover-bg:             darken($navbar-default-bg, 10%) !default;
+$navbar-default-link-active-color:         #fff !default;
+$navbar-default-link-active-bg:            darken($navbar-default-bg, 10%) !default;
+$navbar-default-link-disabled-color:       #ddd !default;
+$navbar-default-link-disabled-bg:          transparent !default;
 
 // Navbar brand label
-$navbar-default-brand-color:               $navbar-default-link-color;
-$navbar-default-brand-hover-color:         #fff;
-$navbar-default-brand-hover-bg:            none;
+$navbar-default-brand-color:               $navbar-default-link-color !default;
+$navbar-default-brand-hover-color:         #fff !default;
+$navbar-default-brand-hover-bg:            none !default;
 
 // Navbar toggle
-$navbar-default-toggle-hover-bg:           darken($navbar-default-bg, 10%);
-$navbar-default-toggle-icon-bar-bg:        #fff;
-$navbar-default-toggle-border-color:       darken($navbar-default-bg, 10%);
+$navbar-default-toggle-hover-bg:           darken($navbar-default-bg, 10%) !default;
+$navbar-default-toggle-icon-bar-bg:        #fff !default;
+$navbar-default-toggle-border-color:       darken($navbar-default-bg, 10%) !default;
 
 
 // Inverted navbar
 // Reset inverted navbar basics
-$navbar-inverse-color:                      #fff;
-$navbar-inverse-bg:                         $brand-info;
-$navbar-inverse-border:                     darken($navbar-inverse-bg, 5%);
+$navbar-inverse-color:                      #fff !default;
+$navbar-inverse-bg:                         $brand-info !default;
+$navbar-inverse-border:                     darken($navbar-inverse-bg, 5%) !default;
 
 // Inverted navbar links
-$navbar-inverse-link-color:                 #fff;
-$navbar-inverse-link-hover-color:           #fff;
-$navbar-inverse-link-hover-bg:              darken($navbar-inverse-bg, 5%);
-$navbar-inverse-link-active-color:          #fff;
-$navbar-inverse-link-active-bg:             darken($navbar-inverse-bg, 5%);
-$navbar-inverse-link-disabled-color:        #ccc;
-$navbar-inverse-link-disabled-bg:           transparent;
+$navbar-inverse-link-color:                 #fff !default;
+$navbar-inverse-link-hover-color:           #fff !default;
+$navbar-inverse-link-hover-bg:              darken($navbar-inverse-bg, 5%) !default;
+$navbar-inverse-link-active-color:          #fff !default;
+$navbar-inverse-link-active-bg:             darken($navbar-inverse-bg, 5%) !default;
+$navbar-inverse-link-disabled-color:        #ccc !default;
+$navbar-inverse-link-disabled-bg:           transparent !default;
 
 // Inverted navbar brand label
-$navbar-inverse-brand-color:                $navbar-inverse-link-color;
-$navbar-inverse-brand-hover-color:          #fff;
-$navbar-inverse-brand-hover-bg:             none;
+$navbar-inverse-brand-color:                $navbar-inverse-link-color !default;
+$navbar-inverse-brand-hover-color:          #fff !default;
+$navbar-inverse-brand-hover-bg:             none !default;
 
 // Inverted navbar toggle
-$navbar-inverse-toggle-hover-bg:            darken($navbar-inverse-bg, 5%);
-$navbar-inverse-toggle-icon-bar-bg:         #fff;
-$navbar-inverse-toggle-border-color:        darken($navbar-inverse-bg, 5%);
+$navbar-inverse-toggle-hover-bg:            darken($navbar-inverse-bg, 5%) !default;
+$navbar-inverse-toggle-icon-bar-bg:         #fff !default;
+$navbar-inverse-toggle-border-color:        darken($navbar-inverse-bg, 5%) !default;
 
 
 //== Navs
@@ -414,97 +414,97 @@ $navbar-inverse-toggle-border-color:        darken($navbar-inverse-bg, 5%);
 //##
 
 //=== Shared nav styles
-$nav-link-padding:                          10px 15px;
-$nav-link-hover-bg:                         $gray-lighter;
+$nav-link-padding:                          10px 15px !default;
+$nav-link-hover-bg:                         $gray-lighter !default;
 
-$nav-disabled-link-color:                   $gray-light;
-$nav-disabled-link-hover-color:             $gray-light;
+$nav-disabled-link-color:                   $gray-light !default;
+$nav-disabled-link-hover-color:             $gray-light !default;
 
 //== Tabs
-$nav-tabs-border-color:                     #ddd;
+$nav-tabs-border-color:                     #ddd !default;
 
-$nav-tabs-link-hover-border-color:          $gray-lighter;
+$nav-tabs-link-hover-border-color:          $gray-lighter !default;
 
-$nav-tabs-active-link-hover-bg:             $body-bg;
-$nav-tabs-active-link-hover-color:          $gray;
-$nav-tabs-active-link-hover-border-color:   #ddd;
+$nav-tabs-active-link-hover-bg:             $body-bg !default;
+$nav-tabs-active-link-hover-color:          $gray !default;
+$nav-tabs-active-link-hover-border-color:   #ddd !default;
 
-$nav-tabs-justified-link-border-color:            #ddd;
-$nav-tabs-justified-active-link-border-color:     $body-bg;
+$nav-tabs-justified-link-border-color:            #ddd !default;
+$nav-tabs-justified-active-link-border-color:     $body-bg !default;
 
 //== Pills
-$nav-pills-border-radius:                   $border-radius-base;
-$nav-pills-active-link-hover-bg:            $component-active-bg;
-$nav-pills-active-link-hover-color:         $component-active-color;
+$nav-pills-border-radius:                   $border-radius-base !default;
+$nav-pills-active-link-hover-bg:            $component-active-bg !default;
+$nav-pills-active-link-hover-color:         $component-active-color !default;
 
 
 //== Pagination
 //
 //##
 
-$pagination-color:                     $link-color;
-$pagination-bg:                        #fff;
-$pagination-border:                    #ddd;
+$pagination-color:                     $link-color !default;
+$pagination-bg:                        #fff !default;
+$pagination-border:                    #ddd !default;
 
-$pagination-hover-color:               $link-hover-color;
-$pagination-hover-bg:                  $gray-lighter;
-$pagination-hover-border:              #ddd;
+$pagination-hover-color:               $link-hover-color !default;
+$pagination-hover-bg:                  $gray-lighter !default;
+$pagination-hover-border:              #ddd !default;
 
-$pagination-active-color:              $gray-light;
-$pagination-active-bg:                 #f5f5f5;
-$pagination-active-border:             $pagination-hover-border;
+$pagination-active-color:              $gray-light !default;
+$pagination-active-bg:                 #f5f5f5 !default;
+$pagination-active-border:             $pagination-hover-border !default;
 
-$pagination-disabled-color:            $gray-light;
-$pagination-disabled-bg:               #fff;
-$pagination-disabled-border:           #ddd;
+$pagination-disabled-color:            $gray-light !default;
+$pagination-disabled-bg:               #fff !default;
+$pagination-disabled-border:           #ddd !default;
 
 
 //== Pager
 //
 //##
 
-$pager-bg:                             $pagination-bg;
-$pager-border:                         $pagination-border;
-$pager-border-radius:                  15px;
+$pager-bg:                             $pagination-bg !default;
+$pager-border:                         $pagination-border !default;
+$pager-border-radius:                  15px !default;
 
-$pager-hover-bg:                       $pagination-hover-bg;
+$pager-hover-bg:                       $pagination-hover-bg !default;
 
-$pager-active-bg:                      $pagination-active-bg;
-$pager-active-color:                   $pagination-active-color;
+$pager-active-bg:                      $pagination-active-bg !default;
+$pager-active-color:                   $pagination-active-color !default;
 
-$pager-disabled-color:                 $gray-light;
+$pager-disabled-color:                 $gray-light !default;
 
 
 //== Jumbotron
 //
 //##
 
-$jumbotron-padding:              30px;
-$jumbotron-color:                inherit;
-$jumbotron-bg:                   $gray-lighter;
-$jumbotron-heading-color:        inherit;
-$jumbotron-font-size:            ceil(($font-size-base * 1.5));
+$jumbotron-padding:              30px !default;
+$jumbotron-color:                inherit !default;
+$jumbotron-bg:                   $gray-lighter !default;
+$jumbotron-heading-color:        inherit !default;
+$jumbotron-font-size:            ceil(($font-size-base * 1.5)) !default;
 
 
 //== Form states and alerts
 //
 //## Define colors for form feedback states and, by default, alerts.
 
-$state-success-text:             #468847;
-$state-success-bg:               #dff0d8;
-$state-success-border:           darken(adjust-hue($state-success-bg, -10), 5%);
+$state-success-text:             #468847 !default;
+$state-success-bg:               #dff0d8 !default;
+$state-success-border:           darken(adjust-hue($state-success-bg, -10), 5%) !default;
 
-$state-info-text:                #3a87ad;
-$state-info-bg:                  #d9edf7;
-$state-info-border:              darken(adjust-hue($state-info-bg, -10), 7%);
+$state-info-text:                #3a87ad !default;
+$state-info-bg:                  #d9edf7 !default;
+$state-info-border:              darken(adjust-hue($state-info-bg, -10), 7%) !default;
 
-$state-warning-text:             #c09853;
-$state-warning-bg:               #fcf8e3;
-$state-warning-border:           darken(adjust-hue($state-warning-bg, -10), 3%);
+$state-warning-text:             #c09853 !default;
+$state-warning-bg:               #fcf8e3 !default;
+$state-warning-border:           darken(adjust-hue($state-warning-bg, -10), 3%) !default;
 
-$state-danger-text:              #b94a48;
-$state-danger-bg:                #f2dede;
-$state-danger-border:            darken(adjust-hue($state-danger-bg, -10), 3%);
+$state-danger-text:              #b94a48 !default;
+$state-danger-bg:                #f2dede !default;
+$state-danger-border:            darken(adjust-hue($state-danger-bg, -10), 3%) !default;
 
 
 //== Tooltips
@@ -512,17 +512,17 @@ $state-danger-border:            darken(adjust-hue($state-danger-bg, -10), 3%);
 //##
 
 //** Tooltip max width
-$tooltip-max-width:           200px;
+$tooltip-max-width:           200px !default;
 //** Tooltip text color
-$tooltip-color:               #fff;
+$tooltip-color:               #fff !default;
 //** Tooltip background color
-$tooltip-bg:                  #000;
-$tooltip-opacity:             .9;
+$tooltip-bg:                  #000 !default;
+$tooltip-opacity:             .9 !default;
 
 //** Tooltip arrow width
-$tooltip-arrow-width:         5px;
+$tooltip-arrow-width:         5px !default;
 //** Tooltip arrow color
-$tooltip-arrow-color:         $tooltip-bg;
+$tooltip-arrow-color:         $tooltip-bg !default;
 
 
 //== Popovers
@@ -530,28 +530,28 @@ $tooltip-arrow-color:         $tooltip-bg;
 //##
 
 //** Popover body background color
-$popover-bg:                          #fff;
+$popover-bg:                          #fff !default;
 //** Popover maximum width
-$popover-max-width:                   276px;
+$popover-max-width:                   276px !default;
 //** Popover border color
-$popover-border-color:                rgba(0,0,0,.2);
+$popover-border-color:                rgba(0,0,0,.2) !default;
 //** Popover fallback border color
-$popover-fallback-border-color:       #ccc;
+$popover-fallback-border-color:       #ccc !default;
 
 //** Popover title background color
-$popover-title-bg:                    darken($popover-bg, 3%);
+$popover-title-bg:                    darken($popover-bg, 3%) !default;
 
 //** Popover arrow width
-$popover-arrow-width:                 10px;
+$popover-arrow-width:                 10px !default;
 //** Popover arrow color
-$popover-arrow-color:                 $popover-bg;
+$popover-arrow-color:                 $popover-bg !default;
 
 //** Popover outer arrow width
-$popover-arrow-outer-width:           ($popover-arrow-width + 1);
+$popover-arrow-outer-width:           ($popover-arrow-width + 1) !default;
 //** Popover outer arrow color
-$popover-arrow-outer-color:           fadein($popover-border-color, 5%);
+$popover-arrow-outer-color:           fadein($popover-border-color, 5%) !default;
 //** Popover outer arrow fallback color
-$popover-arrow-outer-fallback-color:  darken($popover-fallback-border-color, 20%);
+$popover-arrow-outer-fallback-color:  darken($popover-fallback-border-color, 20%) !default;
 
 
 //== Labels
@@ -559,22 +559,22 @@ $popover-arrow-outer-fallback-color:  darken($popover-fallback-border-color, 20%
 //##
 
 //** Default label background color
-$label-default-bg:            $gray-light;
+$label-default-bg:            $gray-light !default;
 //** Primary label background color
-$label-primary-bg:            $brand-primary;
+$label-primary-bg:            $brand-primary !default;
 //** Success label background color
-$label-success-bg:            $brand-success;
+$label-success-bg:            $brand-success !default;
 //** Info label background color
-$label-info-bg:               $brand-info;
+$label-info-bg:               $brand-info !default;
 //** Warning label background color
-$label-warning-bg:            $brand-warning;
+$label-warning-bg:            $brand-warning !default;
 //** Danger label background color
-$label-danger-bg:             $brand-danger;
+$label-danger-bg:             $brand-danger !default;
 
 //** Default label text color
-$label-color:                 #fff;
+$label-color:                 #fff !default;
 //** Default text color of a linked label
-$label-link-hover-color:      #fff;
+$label-link-hover-color:      #fff !default;
 
 
 //== Modals
@@ -582,57 +582,57 @@ $label-link-hover-color:      #fff;
 //##
 
 //** Padding applied to the modal body
-$modal-inner-padding:         20px;
+$modal-inner-padding:         20px !default;
 
 //** Padding applied to the modal title
-$modal-title-padding:         15px;
+$modal-title-padding:         15px !default;
 //** Modal title line-height
-$modal-title-line-height:     $line-height-base;
+$modal-title-line-height:     $line-height-base !default;
 
 //** Background color of modal content area
-$modal-content-bg:                             #fff;
+$modal-content-bg:                             #fff !default;
 //** Modal content border color
-$modal-content-border-color:                   rgba(0,0,0,.2);
+$modal-content-border-color:                   rgba(0,0,0,.2) !default;
 //** Modal content border color **for IE8**
-$modal-content-fallback-border-color:          #999;
+$modal-content-fallback-border-color:          #999 !default;
 
 //** Modal backdrop background color
-$modal-backdrop-bg:           #000;
+$modal-backdrop-bg:           #000 !default;
 //** Modal backdrop opacity
-$modal-backdrop-opacity:      .5;
+$modal-backdrop-opacity:      .5 !default;
 //** Modal header border color
-$modal-header-border-color:   #e5e5e5;
+$modal-header-border-color:   #e5e5e5 !default;
 //** Modal footer border color
-$modal-footer-border-color:   $modal-header-border-color;
+$modal-footer-border-color:   $modal-header-border-color !default;
 
-$modal-lg:                    900px;
-$modal-md:                    600px;
-$modal-sm:                    300px;
+$modal-lg:                    900px !default;
+$modal-md:                    600px !default;
+$modal-sm:                    300px !default;
 
 
 //== Alerts
 //
 //## Define alert colors, border radius, and padding.
 
-$alert-padding:               15px;
-$alert-border-radius:         $border-radius-base;
-$alert-link-font-weight:      bold;
+$alert-padding:               15px !default;
+$alert-border-radius:         $border-radius-base !default;
+$alert-link-font-weight:      bold !default;
 
-$alert-success-bg:            $state-success-bg;
-$alert-success-text:          $state-success-text;
-$alert-success-border:        $state-success-border;
+$alert-success-bg:            $state-success-bg !default;
+$alert-success-text:          $state-success-text !default;
+$alert-success-border:        $state-success-border !default;
 
-$alert-info-bg:               $state-info-bg;
-$alert-info-text:             $state-info-text;
-$alert-info-border:           $state-info-border;
+$alert-info-bg:               $state-info-bg !default;
+$alert-info-text:             $state-info-text !default;
+$alert-info-border:           $state-info-border !default;
 
-$alert-warning-bg:            $state-warning-bg;
-$alert-warning-text:          $state-warning-text;
-$alert-warning-border:        $state-warning-border;
+$alert-warning-bg:            $state-warning-bg !default;
+$alert-warning-text:          $state-warning-text !default;
+$alert-warning-border:        $state-warning-border !default;
 
-$alert-danger-bg:             $state-danger-bg;
-$alert-danger-text:           $state-danger-text;
-$alert-danger-border:         $state-danger-border;
+$alert-danger-bg:             $state-danger-bg !default;
+$alert-danger-text:           $state-danger-text !default;
+$alert-danger-border:         $state-danger-border !default;
 
 
 //== Progress bars
@@ -640,22 +640,22 @@ $alert-danger-border:         $state-danger-border;
 //##
 
 //** Background color of the whole progress component
-$progress-bg:                 #f5f5f5;
+$progress-bg:                 #f5f5f5 !default;
 //** Progress bar text color
-$progress-bar-color:          #fff;
+$progress-bar-color:          #fff !default;
 //** Variable for setting rounded corners on progress bar.
-$progress-border-radius:      $border-radius-base;
+$progress-border-radius:      $border-radius-base !default;
 
 //** Default progress bar color
-$progress-bar-bg:             $brand-primary;
+$progress-bar-bg:             $brand-primary !default;
 //** Success progress bar color
-$progress-bar-success-bg:     $brand-success;
+$progress-bar-success-bg:     $brand-success !default;
 //** Warning progress bar color
-$progress-bar-warning-bg:     $brand-warning;
+$progress-bar-warning-bg:     $brand-warning !default;
 //** Danger progress bar color
-$progress-bar-danger-bg:      $brand-danger;
+$progress-bar-danger-bg:      $brand-danger !default;
 //** Info progress bar color
-$progress-bar-info-bg:        $brand-info;
+$progress-bar-info-bg:        $brand-info !default;
 
 
 //== List group
@@ -663,72 +663,72 @@ $progress-bar-info-bg:        $brand-info;
 //##
 
 //** Background color on `.list-group-item`
-$list-group-bg:                 #fff;
+$list-group-bg:                 #fff !default;
 //** `.list-group-item` border color
-$list-group-border:             #ddd;
+$list-group-border:             #ddd !default;
 //** List group border radius
-$list-group-border-radius:      $border-radius-base;
+$list-group-border-radius:      $border-radius-base !default;
 
 //** Background color of single list items on hover
-$list-group-hover-bg:           #f5f5f5;
+$list-group-hover-bg:           #f5f5f5 !default;
 //** Text color of active list items
-$list-group-active-color:       $component-active-color;
+$list-group-active-color:       $component-active-color !default;
 //** Background color of active list items
-$list-group-active-bg:          $component-active-bg;
+$list-group-active-bg:          $component-active-bg !default;
 //** Border color of active list elements
-$list-group-active-border:      $list-group-active-bg;
+$list-group-active-border:      $list-group-active-bg !default;
 //** Text color for content within active list items
-$list-group-active-text-color:  lighten($list-group-active-bg, 40%);
+$list-group-active-text-color:  lighten($list-group-active-bg, 40%) !default;
 
 //** Text color of disabled list items
-$list-group-disabled-color:      $gray-light;
+$list-group-disabled-color:      $gray-light !default;
 //** Background color of disabled list items
-$list-group-disabled-bg:         $gray-lighter;
+$list-group-disabled-bg:         $gray-lighter !default;
 //** Text color for content within disabled list items
-$list-group-disabled-text-color: $list-group-disabled-color;
+$list-group-disabled-text-color: $list-group-disabled-color !default;
 
-$list-group-link-color:         #555;
-$list-group-link-hover-color:   $list-group-link-color;
-$list-group-link-heading-color: #333;
+$list-group-link-color:         #555 !default;
+$list-group-link-hover-color:   $list-group-link-color !default;
+$list-group-link-heading-color: #333 !default;
 
 
 //== Panels
 //
 //##
 
-$panel-bg:                    #fff;
-$panel-body-padding:          15px;
-$panel-heading-padding:       10px 15px;
-$panel-footer-padding:        $panel-heading-padding;
-$panel-border-radius:         $border-radius-base;
+$panel-bg:                    #fff !default;
+$panel-body-padding:          15px !default;
+$panel-heading-padding:       10px 15px !default;
+$panel-footer-padding:        $panel-heading-padding !default;
+$panel-border-radius:         $border-radius-base !default;
 
 //** Border color for elements within panels
-$panel-inner-border:          #ddd;
-$panel-footer-bg:             #f5f5f5;
+$panel-inner-border:          #ddd !default;
+$panel-footer-bg:             #f5f5f5 !default;
 
-$panel-default-text:          $text-color;
-$panel-default-border:        #ddd;
-$panel-default-heading-bg:    #f5f5f5;
+$panel-default-text:          $text-color !default;
+$panel-default-border:        #ddd !default;
+$panel-default-heading-bg:    #f5f5f5 !default;
 
-$panel-primary-text:          #fff;
-$panel-primary-border:        $panel-default-border;
-$panel-primary-heading-bg:    $brand-primary;
+$panel-primary-text:          #fff !default;
+$panel-primary-border:        $panel-default-border !default;
+$panel-primary-heading-bg:    $brand-primary !default;
 
-$panel-success-text:          $state-success-text;
-$panel-success-border:        $panel-default-border;
-$panel-success-heading-bg:    $brand-success;
+$panel-success-text:          $state-success-text !default;
+$panel-success-border:        $panel-default-border !default;
+$panel-success-heading-bg:    $brand-success !default;
 
-$panel-info-text:             $state-info-text;
-$panel-info-border:           $panel-default-border;
-$panel-info-heading-bg:       $brand-info;
+$panel-info-text:             $state-info-text !default;
+$panel-info-border:           $panel-default-border !default;
+$panel-info-heading-bg:       $brand-info !default;
 
-$panel-warning-text:          $state-warning-text;
-$panel-warning-border:        $panel-default-border;
-$panel-warning-heading-bg:    $brand-warning;
+$panel-warning-text:          $state-warning-text !default;
+$panel-warning-border:        $panel-default-border !default;
+$panel-warning-heading-bg:    $brand-warning !default;
 
-$panel-danger-text:           $state-danger-text;
-$panel-danger-border:         $panel-default-border;
-$panel-danger-heading-bg:     $brand-danger;
+$panel-danger-text:           $state-danger-text !default;
+$panel-danger-border:         $panel-default-border !default;
+$panel-danger-heading-bg:     $brand-danger !default;
 
 
 //== Thumbnails
@@ -736,103 +736,103 @@ $panel-danger-heading-bg:     $brand-danger;
 //##
 
 //** Padding around the thumbnail image
-$thumbnail-padding:           4px;
+$thumbnail-padding:           4px !default;
 //** Thumbnail background color
-$thumbnail-bg:                $body-bg;
+$thumbnail-bg:                $body-bg !default;
 //** Thumbnail border color
-$thumbnail-border:            #ddd;
+$thumbnail-border:            #ddd !default;
 //** Thumbnail border radius
-$thumbnail-border-radius:     $border-radius-base;
+$thumbnail-border-radius:     $border-radius-base !default;
 
 //** Custom text color for thumbnail captions
-$thumbnail-caption-color:     $text-color;
+$thumbnail-caption-color:     $text-color !default;
 //** Padding around the thumbnail caption
-$thumbnail-caption-padding:   9px;
+$thumbnail-caption-padding:   9px !default;
 
 
 //== Wells
 //
 //##
 
-$well-bg:                     #f5f5f5;
-$well-border:                 darken($well-bg, 7%);
+$well-bg:                     #f5f5f5 !default;
+$well-border:                 darken($well-bg, 7%) !default;
 
 
 //== Badges
 //
 //##
 
-$badge-color:                 #fff;
+$badge-color:                 #fff !default;
 //** Linked badge text color on hover
-$badge-link-hover-color:      #fff;
-$badge-bg:                    $brand-primary;
+$badge-link-hover-color:      #fff !default;
+$badge-bg:                    $brand-primary !default;
 
 //** Badge text color in active nav link
-$badge-active-color:          $link-color;
+$badge-active-color:          $link-color !default;
 //** Badge background color in active nav link
-$badge-active-bg:             #fff;
+$badge-active-bg:             #fff !default;
 
-$badge-font-weight:           bold;
-$badge-line-height:           1;
-$badge-border-radius:         10px;
+$badge-font-weight:           bold !default;
+$badge-line-height:           1 !default;
+$badge-border-radius:         10px !default;
 
 
 //== Breadcrumbs
 //
 //##
 
-$breadcrumb-padding-vertical:   8px;
-$breadcrumb-padding-horizontal: 15px;
+$breadcrumb-padding-vertical:   8px !default;
+$breadcrumb-padding-horizontal: 15px !default;
 //** Breadcrumb background color
-$breadcrumb-bg:                 #f5f5f5;
+$breadcrumb-bg:                 #f5f5f5 !default;
 //** Breadcrumb text color
-$breadcrumb-color:              #ccc;
+$breadcrumb-color:              #ccc !default;
 //** Text color of current page in the breadcrumb
-$breadcrumb-active-color:       $gray-light;
+$breadcrumb-active-color:       $gray-light !default;
 //** Textual separator for between breadcrumb elements
-$breadcrumb-separator:          "/";
+$breadcrumb-separator:          "/" !default;
 
 
 //== Carousel
 //
 //##
 
-$carousel-text-shadow:                        0 1px 2px rgba(0,0,0,.6);
+$carousel-text-shadow:                        0 1px 2px rgba(0,0,0,.6) !default;
 
-$carousel-control-color:                      #fff;
-$carousel-control-width:                      15%;
-$carousel-control-opacity:                    .5;
-$carousel-control-font-size:                  20px;
+$carousel-control-color:                      #fff !default;
+$carousel-control-width:                      15% !default;
+$carousel-control-opacity:                    .5 !default;
+$carousel-control-font-size:                  20px !default;
 
-$carousel-indicator-active-bg:                #fff;
-$carousel-indicator-border-color:             #fff;
+$carousel-indicator-active-bg:                #fff !default;
+$carousel-indicator-border-color:             #fff !default;
 
-$carousel-caption-color:                      #fff;
+$carousel-caption-color:                      #fff !default;
 
 
 //== Close
 //
 //##
 
-$close-font-weight:           bold;
-$close-color:                 #000;
-$close-text-shadow:           0 1px 0 #fff;
+$close-font-weight:           bold !default;
+$close-color:                 #000 !default;
+$close-text-shadow:           0 1px 0 #fff !default;
 
 
 //== Code
 //
 //##
 
-$code-color:                  #c7254e;
-$code-bg:                     #f9f2f4;
+$code-color:                  #c7254e !default;
+$code-bg:                     #f9f2f4 !default;
 
-$kbd-color:                   #fff;
-$kbd-bg:                      #333;
+$kbd-color:                   #fff !default;
+$kbd-bg:                      #333 !default;
 
-$pre-bg:                      #f5f5f5;
-$pre-color:                   $gray-dark;
-$pre-border-color:            #ccc;
-$pre-scrollable-max-height:   340px;
+$pre-bg:                      #f5f5f5 !default;
+$pre-color:                   $gray-dark !default;
+$pre-border-color:            #ccc !default;
+$pre-scrollable-max-height:   340px !default;
 
 
 //== Type
@@ -840,22 +840,22 @@ $pre-scrollable-max-height:   340px;
 //##
 
 //** Horizontal offset for forms and lists.
-$component-offset-horizontal: 180px;
+$component-offset-horizontal: 180px !default;
 //** Text muted color
-$text-muted:                  $gray-light;
+$text-muted:                  $gray-light !default;
 //** Abbreviations and acronyms border color
-$abbr-border-color:           $gray-light;
+$abbr-border-color:           $gray-light !default;
 //** Headings small color
-$headings-small-color:        $gray-light;
+$headings-small-color:        $gray-light !default;
 //** Blockquote small color
-$blockquote-small-color:      $gray-light;
+$blockquote-small-color:      $gray-light !default;
 //** Blockquote font size
-$blockquote-font-size:        ($font-size-base * 1.25);
+$blockquote-font-size:        ($font-size-base * 1.25) !default;
 //** Blockquote border color
-$blockquote-border-color:     $gray-lighter;
+$blockquote-border-color:     $gray-lighter !default;
 //** Page header border color
-$page-header-border-color:    $gray-lighter;
+$page-header-border-color:    $gray-lighter !default;
 //** Width of horizontal description list titles
-$dl-horizontal-offset:        $component-offset-horizontal;
+$dl-horizontal-offset:        $component-offset-horizontal !default;
 //** Horizontal line color.
-$hr-border:                   $gray-lighter;
+$hr-border:                   $gray-lighter !default;
diff --git a/cosmo/_variables.scss b/cosmo/_variables.scss
index 334ec3eb..322254c2 100644
--- a/cosmo/_variables.scss
+++ b/cosmo/_variables.scss
@@ -7,18 +7,18 @@
 //
 //## Gray and brand colors for use across Bootstrap.
 
-$gray-base:              #000;
-$gray-darker:            lighten($gray-base, 13.5%); // #222
-$gray-dark:              lighten($gray-base, 20%);   // #333
-$gray:                   lighten($gray-base, 33.5%); // #555
-$gray-light:             lighten($gray-base, 60%);   // #999
-$gray-lighter:           lighten($gray-base, 90%); // #eee
+$gray-base:              #000 !default;
+$gray-darker:            lighten($gray-base, 13.5%) !default; // #222
+$gray-dark:              lighten($gray-base, 20%) !default;   // #333
+$gray:                   lighten($gray-base, 33.5%) !default; // #555
+$gray-light:             lighten($gray-base, 60%) !default;   // #999
+$gray-lighter:           lighten($gray-base, 90%) !default; // #eee
 
-$brand-primary:         #2780E3;
-$brand-success:         #3FB618;
-$brand-info:            #9954BB;
-$brand-warning:         #FF7518;
-$brand-danger:          #FF0039;
+$brand-primary:         #2780E3 !default;
+$brand-success:         #3FB618 !default;
+$brand-info:            #9954BB !default;
+$brand-warning:         #FF7518 !default;
+$brand-danger:          #FF0039 !default;
 
 
 //== Scaffolding
@@ -26,49 +26,49 @@ $brand-danger:          #FF0039;
 //## Settings for some of the most global styles.
 
 //** Background color for ``.
-$body-bg:               #fff;
+$body-bg:               #fff !default;
 //** Global text color on ``.
-$text-color:            $gray-dark;
+$text-color:            $gray-dark !default;
 
 //** Global textual link color.
-$link-color:            $brand-primary;
+$link-color:            $brand-primary !default;
 //** Link hover color set via `darken()` function.
-$link-hover-color:      darken($link-color, 15%);
+$link-hover-color:      darken($link-color, 15%) !default;
 //** Link hover decoration.
-$link-hover-decoration: underline;
+$link-hover-decoration: underline !default;
 
 
 //== Typography
 //
 //## Font, line-height, and color for body text, headings, and more.
 
-$font-family-sans-serif:  "Source Sans Pro", Calibri, Candara, Arial, sans-serif;
-$font-family-serif:       Georgia, "Times New Roman", Times, serif;
+$font-family-sans-serif:  "Source Sans Pro", Calibri, Candara, Arial, sans-serif !default;
+$font-family-serif:       Georgia, "Times New Roman", Times, serif !default;
 //** Default monospace fonts for ``, ``, and `
`.
-$font-family-monospace:   Menlo, Monaco, Consolas, "Courier New", monospace;
-$font-family-base:        $font-family-sans-serif;
+$font-family-monospace:   Menlo, Monaco, Consolas, "Courier New", monospace !default;
+$font-family-base:        $font-family-sans-serif !default;
 
-$font-size-base:          15px;
-$font-size-large:         ceil(($font-size-base * 1.25)); // ~18px
-$font-size-small:         ceil(($font-size-base * 0.85)); // ~12px
+$font-size-base:          15px !default;
+$font-size-large:         ceil(($font-size-base * 1.25)) !default; // ~18px
+$font-size-small:         ceil(($font-size-base * 0.85)) !default; // ~12px
 
-$font-size-h1:            floor(($font-size-base * 2.6)); // ~36px
-$font-size-h2:            floor(($font-size-base * 2.15)); // ~30px
-$font-size-h3:            ceil(($font-size-base * 1.7)); // ~24px
-$font-size-h4:            ceil(($font-size-base * 1.25)); // ~18px
-$font-size-h5:            $font-size-base;
-$font-size-h6:            ceil(($font-size-base * 0.85)); // ~12px
+$font-size-h1:            floor(($font-size-base * 2.6)) !default; // ~36px
+$font-size-h2:            floor(($font-size-base * 2.15)) !default; // ~30px
+$font-size-h3:            ceil(($font-size-base * 1.7)) !default; // ~24px
+$font-size-h4:            ceil(($font-size-base * 1.25)) !default; // ~18px
+$font-size-h5:            $font-size-base !default;
+$font-size-h6:            ceil(($font-size-base * 0.85)) !default; // ~12px
 
 //** Unit-less `line-height` for use in components like buttons.
-$line-height-base:        1.428571429; // 20/14
+$line-height-base:        1.428571429 !default; // 20/14
 //** Computed "line-height" (`font-size` * `line-height`) for use with `margin`, `padding`, etc.
-$line-height-computed:    floor(($font-size-base * $line-height-base)); // ~20px
+$line-height-computed:    floor(($font-size-base * $line-height-base)) !default; // ~20px
 
 //** By default, this inherits from the ``.
-$headings-font-family:    $font-family-base;
-$headings-font-weight:    300;
-$headings-line-height:    1.1;
-$headings-color:          inherit;
+$headings-font-family:    $font-family-base !default;
+$headings-font-weight:    300 !default;
+$headings-line-height:    1.1 !default;
+$headings-color:          inherit !default;
 
 
 //== Iconography
@@ -76,45 +76,45 @@ $headings-color:          inherit;
 //## Specify custom location and filename of the included Glyphicons icon font. Useful for those including Bootstrap via Bower.
 
 //** Load fonts from this directory.
-$icon-font-path:          "../fonts/";
+$icon-font-path:          "../fonts/" !default;
 //** File name for all font files.
-$icon-font-name:          "glyphicons-halflings-regular";
+$icon-font-name:          "glyphicons-halflings-regular" !default;
 //** Element ID within SVG icon file.
-$icon-font-svg-id:        "glyphicons_halflingsregular";
+$icon-font-svg-id:        "glyphicons_halflingsregular" !default;
 
 
 //== Components
 //
 //## Define common padding and border radius sizes and more. Values based on 14px text and 1.428 line-height (~20px to start).
 
-$padding-base-vertical:     10px;
-$padding-base-horizontal:   18px;
+$padding-base-vertical:     10px !default;
+$padding-base-horizontal:   18px !default;
 
-$padding-large-vertical:    18px;
-$padding-large-horizontal:  30px;
+$padding-large-vertical:    18px !default;
+$padding-large-horizontal:  30px !default;
 
-$padding-small-vertical:    5px;
-$padding-small-horizontal:  10px;
+$padding-small-vertical:    5px !default;
+$padding-small-horizontal:  10px !default;
 
-$padding-xs-vertical:       1px;
-$padding-xs-horizontal:     5px;
+$padding-xs-vertical:       1px !default;
+$padding-xs-horizontal:     5px !default;
 
-$line-height-large:         1.3333333; // extra decimals for Win 8.1 Chrome
-$line-height-small:         1.5;
+$line-height-large:         1.3333333 !default; // extra decimals for Win 8.1 Chrome
+$line-height-small:         1.5 !default;
 
-$border-radius-base:        0;
-$border-radius-large:       0;
-$border-radius-small:       0;
+$border-radius-base:        0 !default;
+$border-radius-large:       0 !default;
+$border-radius-small:       0 !default;
 
 //** Global color for active items (e.g., navs or dropdowns).
-$component-active-color:    #fff;
+$component-active-color:    #fff !default;
 //** Global background color for active items (e.g., navs or dropdowns).
-$component-active-bg:       $brand-primary;
+$component-active-bg:       $brand-primary !default;
 
 //** Width of the `border` for generating carets that indicator dropdowns.
-$caret-width-base:          4px;
+$caret-width-base:          4px !default;
 //** Carets increase slightly in size for larger components.
-$caret-width-large:         5px;
+$caret-width-large:         5px !default;
 
 
 //== Tables
@@ -122,53 +122,53 @@ $caret-width-large:         5px;
 //## Customizes the `.table` component with basic values, each used across all table variations.
 
 //** Padding for ``s and ``s.
-$table-cell-padding:            8px;
+$table-cell-padding:            8px !default;
 //** Padding for cells in `.table-condensed`.
-$table-condensed-cell-padding:  5px;
+$table-condensed-cell-padding:  5px !default;
 
 //** Default background color used for all tables.
-$table-bg:                      transparent;
+$table-bg:                      transparent !default;
 //** Background color used for `.table-striped`.
-$table-bg-accent:               #f9f9f9;
+$table-bg-accent:               #f9f9f9 !default;
 //** Background color used for `.table-hover`.
-$table-bg-hover:                #f5f5f5;
-$table-bg-active:               $table-bg-hover;
+$table-bg-hover:                #f5f5f5 !default;
+$table-bg-active:               $table-bg-hover !default;
 
 //** Border color for table and cell borders.
-$table-border-color:            #ddd;
+$table-border-color:            #ddd !default;
 
 
 //== Buttons
 //
 //## For each of Bootstrap's buttons, define text, background and border color.
 
-$btn-font-weight:                normal;
+$btn-font-weight:                normal !default;
 
-$btn-default-color:              #fff;
-$btn-default-bg:                 $gray-darker;
-$btn-default-border:             $btn-default-bg;
+$btn-default-color:              #fff !default;
+$btn-default-bg:                 $gray-darker !default;
+$btn-default-border:             $btn-default-bg !default;
 
-$btn-primary-color:              $btn-default-color;
-$btn-primary-bg:                 $brand-primary;
-$btn-primary-border:             $btn-primary-bg;
+$btn-primary-color:              $btn-default-color !default;
+$btn-primary-bg:                 $brand-primary !default;
+$btn-primary-border:             $btn-primary-bg !default;
 
-$btn-success-color:              $btn-default-color;
-$btn-success-bg:                 $brand-success;
-$btn-success-border:             $btn-success-bg;
+$btn-success-color:              $btn-default-color !default;
+$btn-success-bg:                 $brand-success !default;
+$btn-success-border:             $btn-success-bg !default;
 
-$btn-info-color:                 $btn-default-color;
-$btn-info-bg:                    $brand-info;
-$btn-info-border:                $btn-info-bg;
+$btn-info-color:                 $btn-default-color !default;
+$btn-info-bg:                    $brand-info !default;
+$btn-info-border:                $btn-info-bg !default;
 
-$btn-warning-color:              $btn-default-color;
-$btn-warning-bg:                 $brand-warning;
-$btn-warning-border:             $btn-warning-bg;
+$btn-warning-color:              $btn-default-color !default;
+$btn-warning-bg:                 $brand-warning !default;
+$btn-warning-border:             $btn-warning-bg !default;
 
-$btn-danger-color:               $btn-default-color;
-$btn-danger-bg:                  $brand-danger;
-$btn-danger-border:              $btn-danger-bg;
+$btn-danger-color:               $btn-default-color !default;
+$btn-danger-bg:                  $brand-danger !default;
+$btn-danger-border:              $btn-danger-bg !default;
 
-$btn-link-disabled-color:        $gray-light;
+$btn-link-disabled-color:        $gray-light !default;
 
 
 //== Forms
@@ -176,50 +176,50 @@ $btn-link-disabled-color:        $gray-light;
 //##
 
 //** `` background color
-$input-bg:                       #fff;
+$input-bg:                       #fff !default;
 //** `` background color
-$input-bg-disabled:              $gray-lighter;
+$input-bg-disabled:              $gray-lighter !default;
 
 //** Text color for ``s
-$input-color:                    $text-color;
+$input-color:                    $text-color !default;
 //** `` border color
-$input-border:                   #ccc;
+$input-border:                   #ccc !default;
 
 // TODO: Rename `$input-border-radius` to `$input-border-radius-base` in v4
 //** Default `.form-control` border radius
 // This has no effect on ``s in CSS.
-$input-border-radius:            $border-radius-base;
+$input-border-radius:            $border-radius-base !default;
 //** Large `.form-control` border radius
-$input-border-radius-large:      $border-radius-large;
+$input-border-radius-large:      $border-radius-large !default;
 //** Small `.form-control` border radius
-$input-border-radius-small:      $border-radius-small;
+$input-border-radius-small:      $border-radius-small !default;
 
 //** Border color for inputs on focus
-$input-border-focus:             #66afe9;
+$input-border-focus:             #66afe9 !default;
 
 //** Placeholder text color
-$input-color-placeholder:        $gray-light;
+$input-color-placeholder:        $gray-light !default;
 
 //** Default `.form-control` height
-$input-height-base:              ($line-height-computed + ($padding-base-vertical * 2) + 2);
+$input-height-base:              ($line-height-computed + ($padding-base-vertical * 2) + 2) !default;
 //** Large `.form-control` height
-$input-height-large:             (ceil($font-size-large * $line-height-large) + ($padding-large-vertical * 2) + 2);
+$input-height-large:             (ceil($font-size-large * $line-height-large) + ($padding-large-vertical * 2) + 2) !default;
 //** Small `.form-control` height
-$input-height-small:             (floor($font-size-small * $line-height-small) + ($padding-small-vertical * 2) + 2);
+$input-height-small:             (floor($font-size-small * $line-height-small) + ($padding-small-vertical * 2) + 2) !default;
 
 //** `.form-group` margin
-$form-group-margin-bottom:       15px;
+$form-group-margin-bottom:       15px !default;
 
-$legend-color:                   $text-color;
-$legend-border-color:            #e5e5e5;
+$legend-color:                   $text-color !default;
+$legend-border-color:            #e5e5e5 !default;
 
 //** Background color for textual input addons
-$input-group-addon-bg:           $gray-lighter;
+$input-group-addon-bg:           $gray-lighter !default;
 //** Border color for textual input addons
-$input-group-addon-border-color: $input-border;
+$input-group-addon-border-color: $input-border !default;
 
 //** Disabled cursor for form controls and buttons.
-$cursor-disabled:                not-allowed;
+$cursor-disabled:                not-allowed !default;
 
 
 //== Dropdowns
@@ -227,34 +227,34 @@ $cursor-disabled:                not-allowed;
 //## Dropdown menu container and contents.
 
 //** Background for the dropdown menu.
-$dropdown-bg:                    #fff;
+$dropdown-bg:                    #fff !default;
 //** Dropdown menu `border-color`.
-$dropdown-border:                rgba(0,0,0,.15);
+$dropdown-border:                rgba(0,0,0,.15) !default;
 //** Dropdown menu `border-color` **for IE8**.
-$dropdown-fallback-border:       #ccc;
+$dropdown-fallback-border:       #ccc !default;
 //** Divider color for between dropdown items.
-$dropdown-divider-bg:            #e5e5e5;
+$dropdown-divider-bg:            #e5e5e5 !default;
 
 //** Dropdown link text color.
-$dropdown-link-color:            $gray-dark;
+$dropdown-link-color:            $gray-dark !default;
 //** Hover color for dropdown links.
-$dropdown-link-hover-color:      #fff;
+$dropdown-link-hover-color:      #fff !default;
 //** Hover background for dropdown links.
-$dropdown-link-hover-bg:         $component-active-bg;
+$dropdown-link-hover-bg:         $component-active-bg !default;
 
 //** Active dropdown menu item text color.
-$dropdown-link-active-color:     #fff;
+$dropdown-link-active-color:     #fff !default;
 //** Active dropdown menu item background color.
-$dropdown-link-active-bg:        $component-active-bg;
+$dropdown-link-active-bg:        $component-active-bg !default;
 
 //** Disabled dropdown menu item background color.
-$dropdown-link-disabled-color:   $gray-light;
+$dropdown-link-disabled-color:   $gray-light !default;
 
 //** Text color for headers within dropdown menus.
-$dropdown-header-color:          $gray-light;
+$dropdown-header-color:          $gray-light !default;
 
 //** Deprecated `$dropdown-caret-color` as of v3.1.0
-$dropdown-caret-color:           #000;
+$dropdown-caret-color:           #000 !default;
 
 
 //-- Z-index master list
@@ -264,13 +264,13 @@ $dropdown-caret-color:           #000;
 //
 // Note: These variables are not generated into the Customizer.
 
-$zindex-navbar:            1000;
-$zindex-dropdown:          1000;
-$zindex-popover:           1060;
-$zindex-tooltip:           1070;
-$zindex-navbar-fixed:      1030;
-$zindex-modal-background:  1040;
-$zindex-modal:             1050;
+$zindex-navbar:            1000 !default;
+$zindex-dropdown:          1000 !default;
+$zindex-popover:           1060 !default;
+$zindex-tooltip:           1070 !default;
+$zindex-navbar-fixed:      1030 !default;
+$zindex-modal-background:  1040 !default;
+$zindex-modal:             1050 !default;
 
 
 //== Media queries breakpoints
@@ -279,37 +279,37 @@ $zindex-modal:             1050;
 
 // Extra small screen / phone
 //** Deprecated `$screen-xs` as of v3.0.1
-$screen-xs:                  480px;
+$screen-xs:                  480px !default;
 //** Deprecated `$screen-xs-min` as of v3.2.0
-$screen-xs-min:              $screen-xs;
+$screen-xs-min:              $screen-xs !default;
 //** Deprecated `$screen-phone` as of v3.0.1
-$screen-phone:               $screen-xs-min;
+$screen-phone:               $screen-xs-min !default;
 
 // Small screen / tablet
 //** Deprecated `$screen-sm` as of v3.0.1
-$screen-sm:                  768px;
-$screen-sm-min:              $screen-sm;
+$screen-sm:                  768px !default;
+$screen-sm-min:              $screen-sm !default;
 //** Deprecated `$screen-tablet` as of v3.0.1
-$screen-tablet:              $screen-sm-min;
+$screen-tablet:              $screen-sm-min !default;
 
 // Medium screen / desktop
 //** Deprecated `$screen-md` as of v3.0.1
-$screen-md:                  992px;
-$screen-md-min:              $screen-md;
+$screen-md:                  992px !default;
+$screen-md-min:              $screen-md !default;
 //** Deprecated `$screen-desktop` as of v3.0.1
-$screen-desktop:             $screen-md-min;
+$screen-desktop:             $screen-md-min !default;
 
 // Large screen / wide desktop
 //** Deprecated `$screen-lg` as of v3.0.1
-$screen-lg:                  1200px;
-$screen-lg-min:              $screen-lg;
+$screen-lg:                  1200px !default;
+$screen-lg-min:              $screen-lg !default;
 //** Deprecated `$screen-lg-desktop` as of v3.0.1
-$screen-lg-desktop:          $screen-lg-min;
+$screen-lg-desktop:          $screen-lg-min !default;
 
 // So media queries don't overlap when required, provide a maximum
-$screen-xs-max:              ($screen-sm-min - 1);
-$screen-sm-max:              ($screen-md-min - 1);
-$screen-md-max:              ($screen-lg-min - 1);
+$screen-xs-max:              ($screen-sm-min - 1) !default;
+$screen-sm-max:              ($screen-md-min - 1) !default;
+$screen-md-max:              ($screen-lg-min - 1) !default;
 
 
 //== Grid system
@@ -317,14 +317,14 @@ $screen-md-max:              ($screen-lg-min - 1);
 //## Define your custom responsive grid.
 
 //** Number of columns in the grid.
-$grid-columns:              12;
+$grid-columns:              12 !default;
 //** Padding between columns. Gets divided in half for the left and right.
-$grid-gutter-width:         30px;
+$grid-gutter-width:         30px !default;
 // Navbar collapse
 //** Point at which the navbar becomes uncollapsed.
-$grid-float-breakpoint:     $screen-sm-min;
+$grid-float-breakpoint:     $screen-sm-min !default;
 //** Point at which the navbar begins collapsing.
-$grid-float-breakpoint-max: ($grid-float-breakpoint - 1);
+$grid-float-breakpoint-max: ($grid-float-breakpoint - 1) !default;
 
 
 //== Container sizes
@@ -332,19 +332,19 @@ $grid-float-breakpoint-max: ($grid-float-breakpoint - 1);
 //## Define the maximum width of `.container` for different screen sizes.
 
 // Small screen / tablet
-$container-tablet:             (720px + $grid-gutter-width);
+$container-tablet:             (720px + $grid-gutter-width) !default;
 //** For `$screen-sm-min` and up.
-$container-sm:                 $container-tablet;
+$container-sm:                 $container-tablet !default;
 
 // Medium screen / desktop
-$container-desktop:            (940px + $grid-gutter-width);
+$container-desktop:            (940px + $grid-gutter-width) !default;
 //** For `$screen-md-min` and up.
-$container-md:                 $container-desktop;
+$container-md:                 $container-desktop !default;
 
 // Large screen / wide desktop
-$container-large-desktop:      (1140px + $grid-gutter-width);
+$container-large-desktop:      (1140px + $grid-gutter-width) !default;
 //** For `$screen-lg-min` and up.
-$container-lg:                 $container-large-desktop;
+$container-lg:                 $container-large-desktop !default;
 
 
 //== Navbar
@@ -352,61 +352,61 @@ $container-lg:                 $container-large-desktop;
 //##
 
 // Basics of a navbar
-$navbar-height:                    50px;
-$navbar-margin-bottom:             $line-height-computed;
-$navbar-border-radius:             $border-radius-base;
-$navbar-padding-horizontal:        floor(($grid-gutter-width / 2));
-$navbar-padding-vertical:          (($navbar-height - $line-height-computed) / 2);
-$navbar-collapse-max-height:       340px;
+$navbar-height:                    50px !default;
+$navbar-margin-bottom:             $line-height-computed !default;
+$navbar-border-radius:             $border-radius-base !default;
+$navbar-padding-horizontal:        floor(($grid-gutter-width / 2)) !default;
+$navbar-padding-vertical:          (($navbar-height - $line-height-computed) / 2) !default;
+$navbar-collapse-max-height:       340px !default;
 
-$navbar-default-color:             #fff;
-$navbar-default-bg:                $gray-darker;
-$navbar-default-border:            darken($navbar-default-bg, 6.5%);
+$navbar-default-color:             #fff !default;
+$navbar-default-bg:                $gray-darker !default;
+$navbar-default-border:            darken($navbar-default-bg, 6.5%) !default;
 
 // Navbar links
-$navbar-default-link-color:                #fff;
-$navbar-default-link-hover-color:          #fff;
-$navbar-default-link-hover-bg:             darken($navbar-default-bg, 10%);
-$navbar-default-link-active-color:         $navbar-default-link-hover-color;
-$navbar-default-link-active-bg:            $navbar-default-link-hover-bg;
-$navbar-default-link-disabled-color:       #ccc;
-$navbar-default-link-disabled-bg:          transparent;
+$navbar-default-link-color:                #fff !default;
+$navbar-default-link-hover-color:          #fff !default;
+$navbar-default-link-hover-bg:             darken($navbar-default-bg, 10%) !default;
+$navbar-default-link-active-color:         $navbar-default-link-hover-color !default;
+$navbar-default-link-active-bg:            $navbar-default-link-hover-bg !default;
+$navbar-default-link-disabled-color:       #ccc !default;
+$navbar-default-link-disabled-bg:          transparent !default;
 
 // Navbar brand label
-$navbar-default-brand-color:               $navbar-default-link-color;
-$navbar-default-brand-hover-color:         #fff;
-$navbar-default-brand-hover-bg:            none;
+$navbar-default-brand-color:               $navbar-default-link-color !default;
+$navbar-default-brand-hover-color:         #fff !default;
+$navbar-default-brand-hover-bg:            none !default;
 
 // Navbar toggle
-$navbar-default-toggle-hover-bg:           $navbar-default-link-hover-bg;
-$navbar-default-toggle-icon-bar-bg:        #fff;
-$navbar-default-toggle-border-color:       transparent;
+$navbar-default-toggle-hover-bg:           $navbar-default-link-hover-bg !default;
+$navbar-default-toggle-icon-bar-bg:        #fff !default;
+$navbar-default-toggle-border-color:       transparent !default;
 
 
 // Inverted navbar
 // Reset inverted navbar basics
-$navbar-inverse-color:                      #fff;
-$navbar-inverse-bg:                         $brand-primary;
-$navbar-inverse-border:                     darken($navbar-inverse-bg, 10%);
+$navbar-inverse-color:                      #fff !default;
+$navbar-inverse-bg:                         $brand-primary !default;
+$navbar-inverse-border:                     darken($navbar-inverse-bg, 10%) !default;
 
 // Inverted navbar links
-$navbar-inverse-link-color:                 #fff;
-$navbar-inverse-link-hover-color:           #fff;
-$navbar-inverse-link-hover-bg:              darken($navbar-inverse-bg, 10%);
-$navbar-inverse-link-active-color:          $navbar-inverse-link-hover-color;
-$navbar-inverse-link-active-bg:             $navbar-inverse-link-hover-bg;
-$navbar-inverse-link-disabled-color:        #fff;
-$navbar-inverse-link-disabled-bg:           transparent;
+$navbar-inverse-link-color:                 #fff !default;
+$navbar-inverse-link-hover-color:           #fff !default;
+$navbar-inverse-link-hover-bg:              darken($navbar-inverse-bg, 10%) !default;
+$navbar-inverse-link-active-color:          $navbar-inverse-link-hover-color !default;
+$navbar-inverse-link-active-bg:             $navbar-inverse-link-hover-bg !default;
+$navbar-inverse-link-disabled-color:        #fff !default;
+$navbar-inverse-link-disabled-bg:           transparent !default;
 
 // Inverted navbar brand label
-$navbar-inverse-brand-color:                $navbar-inverse-link-color;
-$navbar-inverse-brand-hover-color:          #fff;
-$navbar-inverse-brand-hover-bg:             none;
+$navbar-inverse-brand-color:                $navbar-inverse-link-color !default;
+$navbar-inverse-brand-hover-color:          #fff !default;
+$navbar-inverse-brand-hover-bg:             none !default;
 
 // Inverted navbar toggle
-$navbar-inverse-toggle-hover-bg:            $navbar-inverse-link-hover-bg;
-$navbar-inverse-toggle-icon-bar-bg:         #fff;
-$navbar-inverse-toggle-border-color:        transparent;
+$navbar-inverse-toggle-hover-bg:            $navbar-inverse-link-hover-bg !default;
+$navbar-inverse-toggle-icon-bar-bg:         #fff !default;
+$navbar-inverse-toggle-border-color:        transparent !default;
 
 
 //== Navs
@@ -414,97 +414,97 @@ $navbar-inverse-toggle-border-color:        transparent;
 //##
 
 //=== Shared nav styles
-$nav-link-padding:                          10px 15px;
-$nav-link-hover-bg:                         $gray-lighter;
+$nav-link-padding:                          10px 15px !default;
+$nav-link-hover-bg:                         $gray-lighter !default;
 
-$nav-disabled-link-color:                   $gray-light;
-$nav-disabled-link-hover-color:             $gray-light;
+$nav-disabled-link-color:                   $gray-light !default;
+$nav-disabled-link-hover-color:             $gray-light !default;
 
 //== Tabs
-$nav-tabs-border-color:                     #ddd;
+$nav-tabs-border-color:                     #ddd !default;
 
-$nav-tabs-link-hover-border-color:          $gray-lighter;
+$nav-tabs-link-hover-border-color:          $gray-lighter !default;
 
-$nav-tabs-active-link-hover-bg:             $body-bg;
-$nav-tabs-active-link-hover-color:          $gray;
-$nav-tabs-active-link-hover-border-color:   #ddd;
+$nav-tabs-active-link-hover-bg:             $body-bg !default;
+$nav-tabs-active-link-hover-color:          $gray !default;
+$nav-tabs-active-link-hover-border-color:   #ddd !default;
 
-$nav-tabs-justified-link-border-color:            #ddd;
-$nav-tabs-justified-active-link-border-color:     $body-bg;
+$nav-tabs-justified-link-border-color:            #ddd !default;
+$nav-tabs-justified-active-link-border-color:     $body-bg !default;
 
 //== Pills
-$nav-pills-border-radius:                   $border-radius-base;
-$nav-pills-active-link-hover-bg:            $component-active-bg;
-$nav-pills-active-link-hover-color:         $component-active-color;
+$nav-pills-border-radius:                   $border-radius-base !default;
+$nav-pills-active-link-hover-bg:            $component-active-bg !default;
+$nav-pills-active-link-hover-color:         $component-active-color !default;
 
 
 //== Pagination
 //
 //##
 
-$pagination-color:                     $link-color;
-$pagination-bg:                        #fff;
-$pagination-border:                    #ddd;
+$pagination-color:                     $link-color !default;
+$pagination-bg:                        #fff !default;
+$pagination-border:                    #ddd !default;
 
-$pagination-hover-color:               $link-hover-color;
-$pagination-hover-bg:                  $gray-lighter;
-$pagination-hover-border:              #ddd;
+$pagination-hover-color:               $link-hover-color !default;
+$pagination-hover-bg:                  $gray-lighter !default;
+$pagination-hover-border:              #ddd !default;
 
-$pagination-active-color:              $gray-light;
-$pagination-active-bg:                 #f5f5f5;
-$pagination-active-border:             #ddd;
+$pagination-active-color:              $gray-light !default;
+$pagination-active-bg:                 #f5f5f5 !default;
+$pagination-active-border:             #ddd !default;
 
-$pagination-disabled-color:            $gray-light;
-$pagination-disabled-bg:               #fff;
-$pagination-disabled-border:           #ddd;
+$pagination-disabled-color:            $gray-light !default;
+$pagination-disabled-bg:               #fff !default;
+$pagination-disabled-border:           #ddd !default;
 
 
 //== Pager
 //
 //##
 
-$pager-bg:                             $pagination-bg;
-$pager-border:                         $pagination-border;
-$pager-border-radius:                  $border-radius-base;
+$pager-bg:                             $pagination-bg !default;
+$pager-border:                         $pagination-border !default;
+$pager-border-radius:                  $border-radius-base !default;
 
-$pager-hover-bg:                       $pagination-hover-bg;
+$pager-hover-bg:                       $pagination-hover-bg !default;
 
-$pager-active-bg:                      $pagination-active-bg;
-$pager-active-color:                   $pagination-active-color;
+$pager-active-bg:                      $pagination-active-bg !default;
+$pager-active-color:                   $pagination-active-color !default;
 
-$pager-disabled-color:                 $gray-light;
+$pager-disabled-color:                 $gray-light !default;
 
 
 //== Jumbotron
 //
 //##
 
-$jumbotron-padding:              30px;
-$jumbotron-color:                inherit;
-$jumbotron-bg:                   $gray-lighter;
-$jumbotron-heading-color:        inherit;
-$jumbotron-font-size:            ceil(($font-size-base * 1.5));
+$jumbotron-padding:              30px !default;
+$jumbotron-color:                inherit !default;
+$jumbotron-bg:                   $gray-lighter !default;
+$jumbotron-heading-color:        inherit !default;
+$jumbotron-font-size:            ceil(($font-size-base * 1.5)) !default;
 
 
 //== Form states and alerts
 //
 //## Define colors for form feedback states and, by default, alerts.
 
-$state-success-text:             #fff;
-$state-success-bg:               $brand-success;
-$state-success-border:           darken(adjust-hue($state-success-bg, -10), 5%);
+$state-success-text:             #fff !default;
+$state-success-bg:               $brand-success !default;
+$state-success-border:           darken(adjust-hue($state-success-bg, -10), 5%) !default;
 
-$state-info-text:                #fff;
-$state-info-bg:                  $brand-info;
-$state-info-border:              darken(adjust-hue($state-info-bg, -10), 7%);
+$state-info-text:                #fff !default;
+$state-info-bg:                  $brand-info !default;
+$state-info-border:              darken(adjust-hue($state-info-bg, -10), 7%) !default;
 
-$state-warning-text:             #fff;
-$state-warning-bg:               $brand-warning;
-$state-warning-border:           darken(adjust-hue($state-warning-bg, -10), 3%);
+$state-warning-text:             #fff !default;
+$state-warning-bg:               $brand-warning !default;
+$state-warning-border:           darken(adjust-hue($state-warning-bg, -10), 3%) !default;
 
-$state-danger-text:              #fff;
-$state-danger-bg:                $brand-danger;
-$state-danger-border:            darken(adjust-hue($state-danger-bg, -10), 3%);
+$state-danger-text:              #fff !default;
+$state-danger-bg:                $brand-danger !default;
+$state-danger-border:            darken(adjust-hue($state-danger-bg, -10), 3%) !default;
 
 
 //== Tooltips
@@ -512,17 +512,17 @@ $state-danger-border:            darken(adjust-hue($state-danger-bg, -10), 3%);
 //##
 
 //** Tooltip max width
-$tooltip-max-width:           200px;
+$tooltip-max-width:           200px !default;
 //** Tooltip text color
-$tooltip-color:               #fff;
+$tooltip-color:               #fff !default;
 //** Tooltip background color
-$tooltip-bg:                  #000;
-$tooltip-opacity:             .9;
+$tooltip-bg:                  #000 !default;
+$tooltip-opacity:             .9 !default;
 
 //** Tooltip arrow width
-$tooltip-arrow-width:         5px;
+$tooltip-arrow-width:         5px !default;
 //** Tooltip arrow color
-$tooltip-arrow-color:         $tooltip-bg;
+$tooltip-arrow-color:         $tooltip-bg !default;
 
 
 //== Popovers
@@ -530,28 +530,28 @@ $tooltip-arrow-color:         $tooltip-bg;
 //##
 
 //** Popover body background color
-$popover-bg:                          #fff;
+$popover-bg:                          #fff !default;
 //** Popover maximum width
-$popover-max-width:                   276px;
+$popover-max-width:                   276px !default;
 //** Popover border color
-$popover-border-color:                rgba(0,0,0,.2);
+$popover-border-color:                rgba(0,0,0,.2) !default;
 //** Popover fallback border color
-$popover-fallback-border-color:       #ccc;
+$popover-fallback-border-color:       #ccc !default;
 
 //** Popover title background color
-$popover-title-bg:                    darken($popover-bg, 3%);
+$popover-title-bg:                    darken($popover-bg, 3%) !default;
 
 //** Popover arrow width
-$popover-arrow-width:                 10px;
+$popover-arrow-width:                 10px !default;
 //** Popover arrow color
-$popover-arrow-color:                 $popover-bg;
+$popover-arrow-color:                 $popover-bg !default;
 
 //** Popover outer arrow width
-$popover-arrow-outer-width:           ($popover-arrow-width + 1);
+$popover-arrow-outer-width:           ($popover-arrow-width + 1) !default;
 //** Popover outer arrow color
-$popover-arrow-outer-color:           fadein($popover-border-color, 5%);
+$popover-arrow-outer-color:           fadein($popover-border-color, 5%) !default;
 //** Popover outer arrow fallback color
-$popover-arrow-outer-fallback-color:  darken($popover-fallback-border-color, 20%);
+$popover-arrow-outer-fallback-color:  darken($popover-fallback-border-color, 20%) !default;
 
 
 //== Labels
@@ -559,22 +559,22 @@ $popover-arrow-outer-fallback-color:  darken($popover-fallback-border-color, 20%
 //##
 
 //** Default label background color
-$label-default-bg:            $btn-default-bg;
+$label-default-bg:            $btn-default-bg !default;
 //** Primary label background color
-$label-primary-bg:            $brand-primary;
+$label-primary-bg:            $brand-primary !default;
 //** Success label background color
-$label-success-bg:            $brand-success;
+$label-success-bg:            $brand-success !default;
 //** Info label background color
-$label-info-bg:               $brand-info;
+$label-info-bg:               $brand-info !default;
 //** Warning label background color
-$label-warning-bg:            $brand-warning;
+$label-warning-bg:            $brand-warning !default;
 //** Danger label background color
-$label-danger-bg:             $brand-danger;
+$label-danger-bg:             $brand-danger !default;
 
 //** Default label text color
-$label-color:                 #fff;
+$label-color:                 #fff !default;
 //** Default text color of a linked label
-$label-link-hover-color:      #fff;
+$label-link-hover-color:      #fff !default;
 
 
 //== Modals
@@ -582,57 +582,57 @@ $label-link-hover-color:      #fff;
 //##
 
 //** Padding applied to the modal body
-$modal-inner-padding:         20px;
+$modal-inner-padding:         20px !default;
 
 //** Padding applied to the modal title
-$modal-title-padding:         15px;
+$modal-title-padding:         15px !default;
 //** Modal title line-height
-$modal-title-line-height:     $line-height-base;
+$modal-title-line-height:     $line-height-base !default;
 
 //** Background color of modal content area
-$modal-content-bg:                             #fff;
+$modal-content-bg:                             #fff !default;
 //** Modal content border color
-$modal-content-border-color:                   transparent;
+$modal-content-border-color:                   transparent !default;
 //** Modal content border color **for IE8**
-$modal-content-fallback-border-color:          #999;
+$modal-content-fallback-border-color:          #999 !default;
 
 //** Modal backdrop background color
-$modal-backdrop-bg:           #000;
+$modal-backdrop-bg:           #000 !default;
 //** Modal backdrop opacity
-$modal-backdrop-opacity:      .5;
+$modal-backdrop-opacity:      .5 !default;
 //** Modal header border color
-$modal-header-border-color:   #e5e5e5;
+$modal-header-border-color:   #e5e5e5 !default;
 //** Modal footer border color
-$modal-footer-border-color:   $modal-header-border-color;
+$modal-footer-border-color:   $modal-header-border-color !default;
 
-$modal-lg:                    900px;
-$modal-md:                    600px;
-$modal-sm:                    300px;
+$modal-lg:                    900px !default;
+$modal-md:                    600px !default;
+$modal-sm:                    300px !default;
 
 
 //== Alerts
 //
 //## Define alert colors, border radius, and padding.
 
-$alert-padding:               15px;
-$alert-border-radius:         $border-radius-base;
-$alert-link-font-weight:      bold;
+$alert-padding:               15px !default;
+$alert-border-radius:         $border-radius-base !default;
+$alert-link-font-weight:      bold !default;
 
-$alert-success-bg:            $state-success-bg;
-$alert-success-text:          $state-success-text;
-$alert-success-border:        $state-success-border;
+$alert-success-bg:            $state-success-bg !default;
+$alert-success-text:          $state-success-text !default;
+$alert-success-border:        $state-success-border !default;
 
-$alert-info-bg:               $state-info-bg;
-$alert-info-text:             $state-info-text;
-$alert-info-border:           $state-info-border;
+$alert-info-bg:               $state-info-bg !default;
+$alert-info-text:             $state-info-text !default;
+$alert-info-border:           $state-info-border !default;
 
-$alert-warning-bg:            $state-warning-bg;
-$alert-warning-text:          $state-warning-text;
-$alert-warning-border:        $state-warning-border;
+$alert-warning-bg:            $state-warning-bg !default;
+$alert-warning-text:          $state-warning-text !default;
+$alert-warning-border:        $state-warning-border !default;
 
-$alert-danger-bg:             $state-danger-bg;
-$alert-danger-text:           $state-danger-text;
-$alert-danger-border:         $state-danger-border;
+$alert-danger-bg:             $state-danger-bg !default;
+$alert-danger-text:           $state-danger-text !default;
+$alert-danger-border:         $state-danger-border !default;
 
 
 //== Progress bars
@@ -640,22 +640,22 @@ $alert-danger-border:         $state-danger-border;
 //##
 
 //** Background color of the whole progress component
-$progress-bg:                 #ccc;
+$progress-bg:                 #ccc !default;
 //** Progress bar text color
-$progress-bar-color:          #fff;
+$progress-bar-color:          #fff !default;
 //** Variable for setting rounded corners on progress bar.
-$progress-border-radius:      $border-radius-base;
+$progress-border-radius:      $border-radius-base !default;
 
 //** Default progress bar color
-$progress-bar-bg:             $brand-primary;
+$progress-bar-bg:             $brand-primary !default;
 //** Success progress bar color
-$progress-bar-success-bg:     $brand-success;
+$progress-bar-success-bg:     $brand-success !default;
 //** Warning progress bar color
-$progress-bar-warning-bg:     $brand-warning;
+$progress-bar-warning-bg:     $brand-warning !default;
 //** Danger progress bar color
-$progress-bar-danger-bg:      $brand-danger;
+$progress-bar-danger-bg:      $brand-danger !default;
 //** Info progress bar color
-$progress-bar-info-bg:        $brand-info;
+$progress-bar-info-bg:        $brand-info !default;
 
 
 //== List group
@@ -663,72 +663,72 @@ $progress-bar-info-bg:        $brand-info;
 //##
 
 //** Background color on `.list-group-item`
-$list-group-bg:                 #fff;
+$list-group-bg:                 #fff !default;
 //** `.list-group-item` border color
-$list-group-border:             #ddd;
+$list-group-border:             #ddd !default;
 //** List group border radius
-$list-group-border-radius:      $border-radius-base;
+$list-group-border-radius:      $border-radius-base !default;
 
 //** Background color of single list items on hover
-$list-group-hover-bg:           #f5f5f5;
+$list-group-hover-bg:           #f5f5f5 !default;
 //** Text color of active list items
-$list-group-active-color:       $component-active-color;
+$list-group-active-color:       $component-active-color !default;
 //** Background color of active list items
-$list-group-active-bg:          $component-active-bg;
+$list-group-active-bg:          $component-active-bg !default;
 //** Border color of active list elements
-$list-group-active-border:      $list-group-border;
+$list-group-active-border:      $list-group-border !default;
 //** Text color for content within active list items
-$list-group-active-text-color:  lighten($list-group-active-bg, 40%);
+$list-group-active-text-color:  lighten($list-group-active-bg, 40%) !default;
 
 //** Text color of disabled list items
-$list-group-disabled-color:      $gray-light;
+$list-group-disabled-color:      $gray-light !default;
 //** Background color of disabled list items
-$list-group-disabled-bg:         $gray-lighter;
+$list-group-disabled-bg:         $gray-lighter !default;
 //** Text color for content within disabled list items
-$list-group-disabled-text-color: $list-group-disabled-color;
+$list-group-disabled-text-color: $list-group-disabled-color !default;
 
-$list-group-link-color:         #555;
-$list-group-link-hover-color:   $list-group-link-color;
-$list-group-link-heading-color: #333;
+$list-group-link-color:         #555 !default;
+$list-group-link-hover-color:   $list-group-link-color !default;
+$list-group-link-heading-color: #333 !default;
 
 
 //== Panels
 //
 //##
 
-$panel-bg:                    #fff;
-$panel-body-padding:          15px;
-$panel-heading-padding:       10px 15px;
-$panel-footer-padding:        $panel-heading-padding;
-$panel-border-radius:         $border-radius-base;
+$panel-bg:                    #fff !default;
+$panel-body-padding:          15px !default;
+$panel-heading-padding:       10px 15px !default;
+$panel-footer-padding:        $panel-heading-padding !default;
+$panel-border-radius:         $border-radius-base !default;
 
 //** Border color for elements within panels
-$panel-inner-border:          #ddd;
-$panel-footer-bg:             #f5f5f5;
+$panel-inner-border:          #ddd !default;
+$panel-footer-bg:             #f5f5f5 !default;
 
-$panel-default-text:          $gray-dark;
-$panel-default-border:        #ddd;
-$panel-default-heading-bg:    #f5f5f5;
+$panel-default-text:          $gray-dark !default;
+$panel-default-border:        #ddd !default;
+$panel-default-heading-bg:    #f5f5f5 !default;
 
-$panel-primary-text:          #fff;
-$panel-primary-border:        $brand-primary;
-$panel-primary-heading-bg:    $brand-primary;
+$panel-primary-text:          #fff !default;
+$panel-primary-border:        $brand-primary !default;
+$panel-primary-heading-bg:    $brand-primary !default;
 
-$panel-success-text:          $state-success-text;
-$panel-success-border:        $state-success-border;
-$panel-success-heading-bg:    $state-success-bg;
+$panel-success-text:          $state-success-text !default;
+$panel-success-border:        $state-success-border !default;
+$panel-success-heading-bg:    $state-success-bg !default;
 
-$panel-info-text:             $state-info-text;
-$panel-info-border:           $state-info-border;
-$panel-info-heading-bg:       $state-info-bg;
+$panel-info-text:             $state-info-text !default;
+$panel-info-border:           $state-info-border !default;
+$panel-info-heading-bg:       $state-info-bg !default;
 
-$panel-warning-text:          $state-warning-text;
-$panel-warning-border:        $state-warning-border;
-$panel-warning-heading-bg:    $state-warning-bg;
+$panel-warning-text:          $state-warning-text !default;
+$panel-warning-border:        $state-warning-border !default;
+$panel-warning-heading-bg:    $state-warning-bg !default;
 
-$panel-danger-text:           $state-danger-text;
-$panel-danger-border:         $state-danger-border;
-$panel-danger-heading-bg:     $state-danger-bg;
+$panel-danger-text:           $state-danger-text !default;
+$panel-danger-border:         $state-danger-border !default;
+$panel-danger-heading-bg:     $state-danger-bg !default;
 
 
 //== Thumbnails
@@ -736,103 +736,103 @@ $panel-danger-heading-bg:     $state-danger-bg;
 //##
 
 //** Padding around the thumbnail image
-$thumbnail-padding:           4px;
+$thumbnail-padding:           4px !default;
 //** Thumbnail background color
-$thumbnail-bg:                $body-bg;
+$thumbnail-bg:                $body-bg !default;
 //** Thumbnail border color
-$thumbnail-border:            #ddd;
+$thumbnail-border:            #ddd !default;
 //** Thumbnail border radius
-$thumbnail-border-radius:     $border-radius-base;
+$thumbnail-border-radius:     $border-radius-base !default;
 
 //** Custom text color for thumbnail captions
-$thumbnail-caption-color:     $text-color;
+$thumbnail-caption-color:     $text-color !default;
 //** Padding around the thumbnail caption
-$thumbnail-caption-padding:   9px;
+$thumbnail-caption-padding:   9px !default;
 
 
 //== Wells
 //
 //##
 
-$well-bg:                     #f5f5f5;
-$well-border:                 darken($well-bg, 7%);
+$well-bg:                     #f5f5f5 !default;
+$well-border:                 darken($well-bg, 7%) !default;
 
 
 //== Badges
 //
 //##
 
-$badge-color:                 #fff;
+$badge-color:                 #fff !default;
 //** Linked badge text color on hover
-$badge-link-hover-color:      #fff;
-$badge-bg:                    $brand-primary;
+$badge-link-hover-color:      #fff !default;
+$badge-bg:                    $brand-primary !default;
 
 //** Badge text color in active nav link
-$badge-active-color:          $link-color;
+$badge-active-color:          $link-color !default;
 //** Badge background color in active nav link
-$badge-active-bg:             #fff;
+$badge-active-bg:             #fff !default;
 
-$badge-font-weight:           bold;
-$badge-line-height:           1;
-$badge-border-radius:         10px;
+$badge-font-weight:           bold !default;
+$badge-line-height:           1 !default;
+$badge-border-radius:         10px !default;
 
 
 //== Breadcrumbs
 //
 //##
 
-$breadcrumb-padding-vertical:   8px;
-$breadcrumb-padding-horizontal: 15px;
+$breadcrumb-padding-vertical:   8px !default;
+$breadcrumb-padding-horizontal: 15px !default;
 //** Breadcrumb background color
-$breadcrumb-bg:                 #f5f5f5;
+$breadcrumb-bg:                 #f5f5f5 !default;
 //** Breadcrumb text color
-$breadcrumb-color:              #ccc;
+$breadcrumb-color:              #ccc !default;
 //** Text color of current page in the breadcrumb
-$breadcrumb-active-color:       $gray-light;
+$breadcrumb-active-color:       $gray-light !default;
 //** Textual separator for between breadcrumb elements
-$breadcrumb-separator:          "/";
+$breadcrumb-separator:          "/" !default;
 
 
 //== Carousel
 //
 //##
 
-$carousel-text-shadow:                        0 1px 2px rgba(0,0,0,.6);
+$carousel-text-shadow:                        0 1px 2px rgba(0,0,0,.6) !default;
 
-$carousel-control-color:                      #fff;
-$carousel-control-width:                      15%;
-$carousel-control-opacity:                    .5;
-$carousel-control-font-size:                  20px;
+$carousel-control-color:                      #fff !default;
+$carousel-control-width:                      15% !default;
+$carousel-control-opacity:                    .5 !default;
+$carousel-control-font-size:                  20px !default;
 
-$carousel-indicator-active-bg:                #fff;
-$carousel-indicator-border-color:             #fff;
+$carousel-indicator-active-bg:                #fff !default;
+$carousel-indicator-border-color:             #fff !default;
 
-$carousel-caption-color:                      #fff;
+$carousel-caption-color:                      #fff !default;
 
 
 //== Close
 //
 //##
 
-$close-font-weight:           bold;
-$close-color:                 #fff;
-$close-text-shadow:           0 1px 0 #fff;
+$close-font-weight:           bold !default;
+$close-color:                 #fff !default;
+$close-text-shadow:           0 1px 0 #fff !default;
 
 
 //== Code
 //
 //##
 
-$code-color:                  #c7254e;
-$code-bg:                     #f9f2f4;
+$code-color:                  #c7254e !default;
+$code-bg:                     #f9f2f4 !default;
 
-$kbd-color:                   #fff;
-$kbd-bg:                      #333;
+$kbd-color:                   #fff !default;
+$kbd-bg:                      #333 !default;
 
-$pre-bg:                      #f5f5f5;
-$pre-color:                   $gray-dark;
-$pre-border-color:            #ccc;
-$pre-scrollable-max-height:   340px;
+$pre-bg:                      #f5f5f5 !default;
+$pre-color:                   $gray-dark !default;
+$pre-border-color:            #ccc !default;
+$pre-scrollable-max-height:   340px !default;
 
 
 //== Type
@@ -840,22 +840,22 @@ $pre-scrollable-max-height:   340px;
 //##
 
 //** Horizontal offset for forms and lists.
-$component-offset-horizontal: 180px;
+$component-offset-horizontal: 180px !default;
 //** Text muted color
-$text-muted:                  $gray-light;
+$text-muted:                  $gray-light !default;
 //** Abbreviations and acronyms border color
-$abbr-border-color:           $gray-light;
+$abbr-border-color:           $gray-light !default;
 //** Headings small color
-$headings-small-color:        $gray-light;
+$headings-small-color:        $gray-light !default;
 //** Blockquote small color
-$blockquote-small-color:      $gray-light;
+$blockquote-small-color:      $gray-light !default;
 //** Blockquote font size
-$blockquote-font-size:        ($font-size-base * 1.25);
+$blockquote-font-size:        ($font-size-base * 1.25) !default;
 //** Blockquote border color
-$blockquote-border-color:     $gray-lighter;
+$blockquote-border-color:     $gray-lighter !default;
 //** Page header border color
-$page-header-border-color:    $gray-lighter;
+$page-header-border-color:    $gray-lighter !default;
 //** Width of horizontal description list titles
-$dl-horizontal-offset:        $component-offset-horizontal;
+$dl-horizontal-offset:        $component-offset-horizontal !default;
 //** Horizontal line color.
-$hr-border:                   $gray-lighter;
+$hr-border:                   $gray-lighter !default;
diff --git a/custom/_variables.scss b/custom/_variables.scss
index 88e0fa91..e1bba601 100644
--- a/custom/_variables.scss
+++ b/custom/_variables.scss
@@ -7,18 +7,18 @@
 //
 //## Gray and brand colors for use across Bootstrap.
 
-$gray-base:              #000;
-$gray-darker:            lighten($gray-base, 13.5%); // #222
-$gray-dark:              lighten($gray-base, 20%);   // #333
-$gray:                   lighten($gray-base, 33.5%); // #555
-$gray-light:             lighten($gray-base, 46.7%); // #777
-$gray-lighter:           lighten($gray-base, 93.5%); // #eee
+$gray-base:              #000 !default;
+$gray-darker:            lighten($gray-base, 13.5%) !default; // #222
+$gray-dark:              lighten($gray-base, 20%) !default;   // #333
+$gray:                   lighten($gray-base, 33.5%) !default; // #555
+$gray-light:             lighten($gray-base, 46.7%) !default; // #777
+$gray-lighter:           lighten($gray-base, 93.5%) !default; // #eee
 
-$brand-primary:         darken(#428bca, 6.5%); // #337ab7
-$brand-success:         #5cb85c;
-$brand-info:            #5bc0de;
-$brand-warning:         #f0ad4e;
-$brand-danger:          #d9534f;
+$brand-primary:         darken(#428bca, 6.5%) !default; // #337ab7
+$brand-success:         #5cb85c !default;
+$brand-info:            #5bc0de !default;
+$brand-warning:         #f0ad4e !default;
+$brand-danger:          #d9534f !default;
 
 
 //== Scaffolding
@@ -26,49 +26,49 @@ $brand-danger:          #d9534f;
 //## Settings for some of the most global styles.
 
 //** Background color for ``.
-$body-bg:               #fff;
+$body-bg:               #fff !default;
 //** Global text color on ``.
-$text-color:            $gray-dark;
+$text-color:            $gray-dark !default;
 
 //** Global textual link color.
-$link-color:            $brand-primary;
+$link-color:            $brand-primary !default;
 //** Link hover color set via `darken()` function.
-$link-hover-color:      darken($link-color, 15%);
+$link-hover-color:      darken($link-color, 15%) !default;
 //** Link hover decoration.
-$link-hover-decoration: underline;
+$link-hover-decoration: underline !default;
 
 
 //== Typography
 //
 //## Font, line-height, and color for body text, headings, and more.
 
-$font-family-sans-serif:  "Helvetica Neue", Helvetica, Arial, sans-serif;
-$font-family-serif:       Georgia, "Times New Roman", Times, serif;
+$font-family-sans-serif:  "Helvetica Neue", Helvetica, Arial, sans-serif !default;
+$font-family-serif:       Georgia, "Times New Roman", Times, serif !default;
 //** Default monospace fonts for ``, ``, and `
`.
-$font-family-monospace:   Menlo, Monaco, Consolas, "Courier New", monospace;
-$font-family-base:        $font-family-sans-serif;
+$font-family-monospace:   Menlo, Monaco, Consolas, "Courier New", monospace !default;
+$font-family-base:        $font-family-sans-serif !default;
 
-$font-size-base:          14px;
-$font-size-large:         ceil(($font-size-base * 1.25)); // ~18px
-$font-size-small:         ceil(($font-size-base * 0.85)); // ~12px
+$font-size-base:          14px !default;
+$font-size-large:         ceil(($font-size-base * 1.25)) !default; // ~18px
+$font-size-small:         ceil(($font-size-base * 0.85)) !default; // ~12px
 
-$font-size-h1:            floor(($font-size-base * 2.6)); // ~36px
-$font-size-h2:            floor(($font-size-base * 2.15)); // ~30px
-$font-size-h3:            ceil(($font-size-base * 1.7)); // ~24px
-$font-size-h4:            ceil(($font-size-base * 1.25)); // ~18px
-$font-size-h5:            $font-size-base;
-$font-size-h6:            ceil(($font-size-base * 0.85)); // ~12px
+$font-size-h1:            floor(($font-size-base * 2.6)) !default; // ~36px
+$font-size-h2:            floor(($font-size-base * 2.15)) !default; // ~30px
+$font-size-h3:            ceil(($font-size-base * 1.7)) !default; // ~24px
+$font-size-h4:            ceil(($font-size-base * 1.25)) !default; // ~18px
+$font-size-h5:            $font-size-base !default;
+$font-size-h6:            ceil(($font-size-base * 0.85)) !default; // ~12px
 
 //** Unit-less `line-height` for use in components like buttons.
-$line-height-base:        1.428571429; // 20/14
+$line-height-base:        1.428571429 !default; // 20/14
 //** Computed "line-height" (`font-size` * `line-height`) for use with `margin`, `padding`, etc.
-$line-height-computed:    floor(($font-size-base * $line-height-base)); // ~20px
+$line-height-computed:    floor(($font-size-base * $line-height-base)) !default; // ~20px
 
 //** By default, this inherits from the ``.
-$headings-font-family:    inherit;
-$headings-font-weight:    500;
-$headings-line-height:    1.1;
-$headings-color:          inherit;
+$headings-font-family:    inherit !default;
+$headings-font-weight:    500 !default;
+$headings-line-height:    1.1 !default;
+$headings-color:          inherit !default;
 
 
 //== Iconography
@@ -76,45 +76,45 @@ $headings-color:          inherit;
 //## Specify custom location and filename of the included Glyphicons icon font. Useful for those including Bootstrap via Bower.
 
 //** Load fonts from this directory.
-$icon-font-path:          "../fonts/";
+$icon-font-path:          "../fonts/" !default;
 //** File name for all font files.
-$icon-font-name:          "glyphicons-halflings-regular";
+$icon-font-name:          "glyphicons-halflings-regular" !default;
 //** Element ID within SVG icon file.
-$icon-font-svg-id:        "glyphicons_halflingsregular";
+$icon-font-svg-id:        "glyphicons_halflingsregular" !default;
 
 
 //== Components
 //
 //## Define common padding and border radius sizes and more. Values based on 14px text and 1.428 line-height (~20px to start).
 
-$padding-base-vertical:     6px;
-$padding-base-horizontal:   12px;
+$padding-base-vertical:     6px !default;
+$padding-base-horizontal:   12px !default;
 
-$padding-large-vertical:    10px;
-$padding-large-horizontal:  16px;
+$padding-large-vertical:    10px !default;
+$padding-large-horizontal:  16px !default;
 
-$padding-small-vertical:    5px;
-$padding-small-horizontal:  10px;
+$padding-small-vertical:    5px !default;
+$padding-small-horizontal:  10px !default;
 
-$padding-xs-vertical:       1px;
-$padding-xs-horizontal:     5px;
+$padding-xs-vertical:       1px !default;
+$padding-xs-horizontal:     5px !default;
 
-$line-height-large:         1.3333333; // extra decimals for Win 8.1 Chrome
-$line-height-small:         1.5;
+$line-height-large:         1.3333333 !default; // extra decimals for Win 8.1 Chrome
+$line-height-small:         1.5 !default;
 
-$border-radius-base:        4px;
-$border-radius-large:       6px;
-$border-radius-small:       3px;
+$border-radius-base:        4px !default;
+$border-radius-large:       6px !default;
+$border-radius-small:       3px !default;
 
 //** Global color for active items (e.g., navs or dropdowns).
-$component-active-color:    #fff;
+$component-active-color:    #fff !default;
 //** Global background color for active items (e.g., navs or dropdowns).
-$component-active-bg:       $brand-primary;
+$component-active-bg:       $brand-primary !default;
 
 //** Width of the `border` for generating carets that indicator dropdowns.
-$caret-width-base:          4px;
+$caret-width-base:          4px !default;
 //** Carets increase slightly in size for larger components.
-$caret-width-large:         5px;
+$caret-width-large:         5px !default;
 
 
 //== Tables
@@ -122,53 +122,53 @@ $caret-width-large:         5px;
 //## Customizes the `.table` component with basic values, each used across all table variations.
 
 //** Padding for ``s and ``s.
-$table-cell-padding:            8px;
+$table-cell-padding:            8px !default;
 //** Padding for cells in `.table-condensed`.
-$table-condensed-cell-padding:  5px;
+$table-condensed-cell-padding:  5px !default;
 
 //** Default background color used for all tables.
-$table-bg:                      transparent;
+$table-bg:                      transparent !default;
 //** Background color used for `.table-striped`.
-$table-bg-accent:               #f9f9f9;
+$table-bg-accent:               #f9f9f9 !default;
 //** Background color used for `.table-hover`.
-$table-bg-hover:                #f5f5f5;
-$table-bg-active:               $table-bg-hover;
+$table-bg-hover:                #f5f5f5 !default;
+$table-bg-active:               $table-bg-hover !default;
 
 //** Border color for table and cell borders.
-$table-border-color:            #ddd;
+$table-border-color:            #ddd !default;
 
 
 //== Buttons
 //
 //## For each of Bootstrap's buttons, define text, background and border color.
 
-$btn-font-weight:                normal;
+$btn-font-weight:                normal !default;
 
-$btn-default-color:              #333;
-$btn-default-bg:                 #fff;
-$btn-default-border:             #ccc;
+$btn-default-color:              #333 !default;
+$btn-default-bg:                 #fff !default;
+$btn-default-border:             #ccc !default;
 
-$btn-primary-color:              #fff;
-$btn-primary-bg:                 $brand-primary;
-$btn-primary-border:             darken($btn-primary-bg, 5%);
+$btn-primary-color:              #fff !default;
+$btn-primary-bg:                 $brand-primary !default;
+$btn-primary-border:             darken($btn-primary-bg, 5%) !default;
 
-$btn-success-color:              #fff;
-$btn-success-bg:                 $brand-success;
-$btn-success-border:             darken($btn-success-bg, 5%);
+$btn-success-color:              #fff !default;
+$btn-success-bg:                 $brand-success !default;
+$btn-success-border:             darken($btn-success-bg, 5%) !default;
 
-$btn-info-color:                 #fff;
-$btn-info-bg:                    $brand-info;
-$btn-info-border:                darken($btn-info-bg, 5%);
+$btn-info-color:                 #fff !default;
+$btn-info-bg:                    $brand-info !default;
+$btn-info-border:                darken($btn-info-bg, 5%) !default;
 
-$btn-warning-color:              #fff;
-$btn-warning-bg:                 $brand-warning;
-$btn-warning-border:             darken($btn-warning-bg, 5%);
+$btn-warning-color:              #fff !default;
+$btn-warning-bg:                 $brand-warning !default;
+$btn-warning-border:             darken($btn-warning-bg, 5%) !default;
 
-$btn-danger-color:               #fff;
-$btn-danger-bg:                  $brand-danger;
-$btn-danger-border:              darken($btn-danger-bg, 5%);
+$btn-danger-color:               #fff !default;
+$btn-danger-bg:                  $brand-danger !default;
+$btn-danger-border:              darken($btn-danger-bg, 5%) !default;
 
-$btn-link-disabled-color:        $gray-light;
+$btn-link-disabled-color:        $gray-light !default;
 
 
 //== Forms
@@ -176,50 +176,50 @@ $btn-link-disabled-color:        $gray-light;
 //##
 
 //** `` background color
-$input-bg:                       #fff;
+$input-bg:                       #fff !default;
 //** `` background color
-$input-bg-disabled:              $gray-lighter;
+$input-bg-disabled:              $gray-lighter !default;
 
 //** Text color for ``s
-$input-color:                    $gray;
+$input-color:                    $gray !default;
 //** `` border color
-$input-border:                   #ccc;
+$input-border:                   #ccc !default;
 
 // TODO: Rename `$input-border-radius` to `$input-border-radius-base` in v4
 //** Default `.form-control` border radius
 // This has no effect on ``s in CSS.
-$input-border-radius:            $border-radius-base;
+$input-border-radius:            $border-radius-base !default;
 //** Large `.form-control` border radius
-$input-border-radius-large:      $border-radius-large;
+$input-border-radius-large:      $border-radius-large !default;
 //** Small `.form-control` border radius
-$input-border-radius-small:      $border-radius-small;
+$input-border-radius-small:      $border-radius-small !default;
 
 //** Border color for inputs on focus
-$input-border-focus:             #66afe9;
+$input-border-focus:             #66afe9 !default;
 
 //** Placeholder text color
-$input-color-placeholder:        #999;
+$input-color-placeholder:        #999 !default;
 
 //** Default `.form-control` height
-$input-height-base:              ($line-height-computed + ($padding-base-vertical * 2) + 2);
+$input-height-base:              ($line-height-computed + ($padding-base-vertical * 2) + 2) !default;
 //** Large `.form-control` height
-$input-height-large:             (ceil($font-size-large * $line-height-large) + ($padding-large-vertical * 2) + 2);
+$input-height-large:             (ceil($font-size-large * $line-height-large) + ($padding-large-vertical * 2) + 2) !default;
 //** Small `.form-control` height
-$input-height-small:             (floor($font-size-small * $line-height-small) + ($padding-small-vertical * 2) + 2);
+$input-height-small:             (floor($font-size-small * $line-height-small) + ($padding-small-vertical * 2) + 2) !default;
 
 //** `.form-group` margin
-$form-group-margin-bottom:       15px;
+$form-group-margin-bottom:       15px !default;
 
-$legend-color:                   $gray-dark;
-$legend-border-color:            #e5e5e5;
+$legend-color:                   $gray-dark !default;
+$legend-border-color:            #e5e5e5 !default;
 
 //** Background color for textual input addons
-$input-group-addon-bg:           $gray-lighter;
+$input-group-addon-bg:           $gray-lighter !default;
 //** Border color for textual input addons
-$input-group-addon-border-color: $input-border;
+$input-group-addon-border-color: $input-border !default;
 
 //** Disabled cursor for form controls and buttons.
-$cursor-disabled:                not-allowed;
+$cursor-disabled:                not-allowed !default;
 
 
 //== Dropdowns
@@ -227,34 +227,34 @@ $cursor-disabled:                not-allowed;
 //## Dropdown menu container and contents.
 
 //** Background for the dropdown menu.
-$dropdown-bg:                    #fff;
+$dropdown-bg:                    #fff !default;
 //** Dropdown menu `border-color`.
-$dropdown-border:                rgba(0,0,0,.15);
+$dropdown-border:                rgba(0,0,0,.15) !default;
 //** Dropdown menu `border-color` **for IE8**.
-$dropdown-fallback-border:       #ccc;
+$dropdown-fallback-border:       #ccc !default;
 //** Divider color for between dropdown items.
-$dropdown-divider-bg:            #e5e5e5;
+$dropdown-divider-bg:            #e5e5e5 !default;
 
 //** Dropdown link text color.
-$dropdown-link-color:            $gray-dark;
+$dropdown-link-color:            $gray-dark !default;
 //** Hover color for dropdown links.
-$dropdown-link-hover-color:      darken($gray-dark, 5%);
+$dropdown-link-hover-color:      darken($gray-dark, 5%) !default;
 //** Hover background for dropdown links.
-$dropdown-link-hover-bg:         #f5f5f5;
+$dropdown-link-hover-bg:         #f5f5f5 !default;
 
 //** Active dropdown menu item text color.
-$dropdown-link-active-color:     $component-active-color;
+$dropdown-link-active-color:     $component-active-color !default;
 //** Active dropdown menu item background color.
-$dropdown-link-active-bg:        $component-active-bg;
+$dropdown-link-active-bg:        $component-active-bg !default;
 
 //** Disabled dropdown menu item background color.
-$dropdown-link-disabled-color:   $gray-light;
+$dropdown-link-disabled-color:   $gray-light !default;
 
 //** Text color for headers within dropdown menus.
-$dropdown-header-color:          $gray-light;
+$dropdown-header-color:          $gray-light !default;
 
 //** Deprecated `$dropdown-caret-color` as of v3.1.0
-$dropdown-caret-color:           #000;
+$dropdown-caret-color:           #000 !default;
 
 
 //-- Z-index master list
@@ -264,13 +264,13 @@ $dropdown-caret-color:           #000;
 //
 // Note: These variables are not generated into the Customizer.
 
-$zindex-navbar:            1000;
-$zindex-dropdown:          1000;
-$zindex-popover:           1060;
-$zindex-tooltip:           1070;
-$zindex-navbar-fixed:      1030;
-$zindex-modal-background:  1040;
-$zindex-modal:             1050;
+$zindex-navbar:            1000 !default;
+$zindex-dropdown:          1000 !default;
+$zindex-popover:           1060 !default;
+$zindex-tooltip:           1070 !default;
+$zindex-navbar-fixed:      1030 !default;
+$zindex-modal-background:  1040 !default;
+$zindex-modal:             1050 !default;
 
 
 //== Media queries breakpoints
@@ -279,37 +279,37 @@ $zindex-modal:             1050;
 
 // Extra small screen / phone
 //** Deprecated `$screen-xs` as of v3.0.1
-$screen-xs:                  480px;
+$screen-xs:                  480px !default;
 //** Deprecated `$screen-xs-min` as of v3.2.0
-$screen-xs-min:              $screen-xs;
+$screen-xs-min:              $screen-xs !default;
 //** Deprecated `$screen-phone` as of v3.0.1
-$screen-phone:               $screen-xs-min;
+$screen-phone:               $screen-xs-min !default;
 
 // Small screen / tablet
 //** Deprecated `$screen-sm` as of v3.0.1
-$screen-sm:                  768px;
-$screen-sm-min:              $screen-sm;
+$screen-sm:                  768px !default;
+$screen-sm-min:              $screen-sm !default;
 //** Deprecated `$screen-tablet` as of v3.0.1
-$screen-tablet:              $screen-sm-min;
+$screen-tablet:              $screen-sm-min !default;
 
 // Medium screen / desktop
 //** Deprecated `$screen-md` as of v3.0.1
-$screen-md:                  992px;
-$screen-md-min:              $screen-md;
+$screen-md:                  992px !default;
+$screen-md-min:              $screen-md !default;
 //** Deprecated `$screen-desktop` as of v3.0.1
-$screen-desktop:             $screen-md-min;
+$screen-desktop:             $screen-md-min !default;
 
 // Large screen / wide desktop
 //** Deprecated `$screen-lg` as of v3.0.1
-$screen-lg:                  1200px;
-$screen-lg-min:              $screen-lg;
+$screen-lg:                  1200px !default;
+$screen-lg-min:              $screen-lg !default;
 //** Deprecated `$screen-lg-desktop` as of v3.0.1
-$screen-lg-desktop:          $screen-lg-min;
+$screen-lg-desktop:          $screen-lg-min !default;
 
 // So media queries don't overlap when required, provide a maximum
-$screen-xs-max:              ($screen-sm-min - 1);
-$screen-sm-max:              ($screen-md-min - 1);
-$screen-md-max:              ($screen-lg-min - 1);
+$screen-xs-max:              ($screen-sm-min - 1) !default;
+$screen-sm-max:              ($screen-md-min - 1) !default;
+$screen-md-max:              ($screen-lg-min - 1) !default;
 
 
 //== Grid system
@@ -317,14 +317,14 @@ $screen-md-max:              ($screen-lg-min - 1);
 //## Define your custom responsive grid.
 
 //** Number of columns in the grid.
-$grid-columns:              12;
+$grid-columns:              12 !default;
 //** Padding between columns. Gets divided in half for the left and right.
-$grid-gutter-width:         30px;
+$grid-gutter-width:         30px !default;
 // Navbar collapse
 //** Point at which the navbar becomes uncollapsed.
-$grid-float-breakpoint:     $screen-sm-min;
+$grid-float-breakpoint:     $screen-sm-min !default;
 //** Point at which the navbar begins collapsing.
-$grid-float-breakpoint-max: ($grid-float-breakpoint - 1);
+$grid-float-breakpoint-max: ($grid-float-breakpoint - 1) !default;
 
 
 //== Container sizes
@@ -332,19 +332,19 @@ $grid-float-breakpoint-max: ($grid-float-breakpoint - 1);
 //## Define the maximum width of `.container` for different screen sizes.
 
 // Small screen / tablet
-$container-tablet:             (720px + $grid-gutter-width);
+$container-tablet:             (720px + $grid-gutter-width) !default;
 //** For `$screen-sm-min` and up.
-$container-sm:                 $container-tablet;
+$container-sm:                 $container-tablet !default;
 
 // Medium screen / desktop
-$container-desktop:            (940px + $grid-gutter-width);
+$container-desktop:            (940px + $grid-gutter-width) !default;
 //** For `$screen-md-min` and up.
-$container-md:                 $container-desktop;
+$container-md:                 $container-desktop !default;
 
 // Large screen / wide desktop
-$container-large-desktop:      (1140px + $grid-gutter-width);
+$container-large-desktop:      (1140px + $grid-gutter-width) !default;
 //** For `$screen-lg-min` and up.
-$container-lg:                 $container-large-desktop;
+$container-lg:                 $container-large-desktop !default;
 
 
 //== Navbar
@@ -352,61 +352,61 @@ $container-lg:                 $container-large-desktop;
 //##
 
 // Basics of a navbar
-$navbar-height:                    50px;
-$navbar-margin-bottom:             $line-height-computed;
-$navbar-border-radius:             $border-radius-base;
-$navbar-padding-horizontal:        floor(($grid-gutter-width / 2));
-$navbar-padding-vertical:          (($navbar-height - $line-height-computed) / 2);
-$navbar-collapse-max-height:       340px;
+$navbar-height:                    50px !default;
+$navbar-margin-bottom:             $line-height-computed !default;
+$navbar-border-radius:             $border-radius-base !default;
+$navbar-padding-horizontal:        floor(($grid-gutter-width / 2)) !default;
+$navbar-padding-vertical:          (($navbar-height - $line-height-computed) / 2) !default;
+$navbar-collapse-max-height:       340px !default;
 
-$navbar-default-color:             #777;
-$navbar-default-bg:                #f8f8f8;
-$navbar-default-border:            darken($navbar-default-bg, 6.5%);
+$navbar-default-color:             #777 !default;
+$navbar-default-bg:                #f8f8f8 !default;
+$navbar-default-border:            darken($navbar-default-bg, 6.5%) !default;
 
 // Navbar links
-$navbar-default-link-color:                #777;
-$navbar-default-link-hover-color:          #333;
-$navbar-default-link-hover-bg:             transparent;
-$navbar-default-link-active-color:         #555;
-$navbar-default-link-active-bg:            darken($navbar-default-bg, 6.5%);
-$navbar-default-link-disabled-color:       #ccc;
-$navbar-default-link-disabled-bg:          transparent;
+$navbar-default-link-color:                #777 !default;
+$navbar-default-link-hover-color:          #333 !default;
+$navbar-default-link-hover-bg:             transparent !default;
+$navbar-default-link-active-color:         #555 !default;
+$navbar-default-link-active-bg:            darken($navbar-default-bg, 6.5%) !default;
+$navbar-default-link-disabled-color:       #ccc !default;
+$navbar-default-link-disabled-bg:          transparent !default;
 
 // Navbar brand label
-$navbar-default-brand-color:               $navbar-default-link-color;
-$navbar-default-brand-hover-color:         darken($navbar-default-brand-color, 10%);
-$navbar-default-brand-hover-bg:            transparent;
+$navbar-default-brand-color:               $navbar-default-link-color !default;
+$navbar-default-brand-hover-color:         darken($navbar-default-brand-color, 10%) !default;
+$navbar-default-brand-hover-bg:            transparent !default;
 
 // Navbar toggle
-$navbar-default-toggle-hover-bg:           #ddd;
-$navbar-default-toggle-icon-bar-bg:        #888;
-$navbar-default-toggle-border-color:       #ddd;
+$navbar-default-toggle-hover-bg:           #ddd !default;
+$navbar-default-toggle-icon-bar-bg:        #888 !default;
+$navbar-default-toggle-border-color:       #ddd !default;
 
 
 // Inverted navbar
 // Reset inverted navbar basics
-$navbar-inverse-color:                      lighten($gray-light, 15%);
-$navbar-inverse-bg:                         #222;
-$navbar-inverse-border:                     darken($navbar-inverse-bg, 10%);
+$navbar-inverse-color:                      lighten($gray-light, 15%) !default;
+$navbar-inverse-bg:                         #222 !default;
+$navbar-inverse-border:                     darken($navbar-inverse-bg, 10%) !default;
 
 // Inverted navbar links
-$navbar-inverse-link-color:                 lighten($gray-light, 15%);
-$navbar-inverse-link-hover-color:           #fff;
-$navbar-inverse-link-hover-bg:              transparent;
-$navbar-inverse-link-active-color:          $navbar-inverse-link-hover-color;
-$navbar-inverse-link-active-bg:             darken($navbar-inverse-bg, 10%);
-$navbar-inverse-link-disabled-color:        #444;
-$navbar-inverse-link-disabled-bg:           transparent;
+$navbar-inverse-link-color:                 lighten($gray-light, 15%) !default;
+$navbar-inverse-link-hover-color:           #fff !default;
+$navbar-inverse-link-hover-bg:              transparent !default;
+$navbar-inverse-link-active-color:          $navbar-inverse-link-hover-color !default;
+$navbar-inverse-link-active-bg:             darken($navbar-inverse-bg, 10%) !default;
+$navbar-inverse-link-disabled-color:        #444 !default;
+$navbar-inverse-link-disabled-bg:           transparent !default;
 
 // Inverted navbar brand label
-$navbar-inverse-brand-color:                $navbar-inverse-link-color;
-$navbar-inverse-brand-hover-color:          #fff;
-$navbar-inverse-brand-hover-bg:             transparent;
+$navbar-inverse-brand-color:                $navbar-inverse-link-color !default;
+$navbar-inverse-brand-hover-color:          #fff !default;
+$navbar-inverse-brand-hover-bg:             transparent !default;
 
 // Inverted navbar toggle
-$navbar-inverse-toggle-hover-bg:            #333;
-$navbar-inverse-toggle-icon-bar-bg:         #fff;
-$navbar-inverse-toggle-border-color:        #333;
+$navbar-inverse-toggle-hover-bg:            #333 !default;
+$navbar-inverse-toggle-icon-bar-bg:         #fff !default;
+$navbar-inverse-toggle-border-color:        #333 !default;
 
 
 //== Navs
@@ -414,97 +414,97 @@ $navbar-inverse-toggle-border-color:        #333;
 //##
 
 //=== Shared nav styles
-$nav-link-padding:                          10px 15px;
-$nav-link-hover-bg:                         $gray-lighter;
+$nav-link-padding:                          10px 15px !default;
+$nav-link-hover-bg:                         $gray-lighter !default;
 
-$nav-disabled-link-color:                   $gray-light;
-$nav-disabled-link-hover-color:             $gray-light;
+$nav-disabled-link-color:                   $gray-light !default;
+$nav-disabled-link-hover-color:             $gray-light !default;
 
 //== Tabs
-$nav-tabs-border-color:                     #ddd;
+$nav-tabs-border-color:                     #ddd !default;
 
-$nav-tabs-link-hover-border-color:          $gray-lighter;
+$nav-tabs-link-hover-border-color:          $gray-lighter !default;
 
-$nav-tabs-active-link-hover-bg:             $body-bg;
-$nav-tabs-active-link-hover-color:          $gray;
-$nav-tabs-active-link-hover-border-color:   #ddd;
+$nav-tabs-active-link-hover-bg:             $body-bg !default;
+$nav-tabs-active-link-hover-color:          $gray !default;
+$nav-tabs-active-link-hover-border-color:   #ddd !default;
 
-$nav-tabs-justified-link-border-color:            #ddd;
-$nav-tabs-justified-active-link-border-color:     $body-bg;
+$nav-tabs-justified-link-border-color:            #ddd !default;
+$nav-tabs-justified-active-link-border-color:     $body-bg !default;
 
 //== Pills
-$nav-pills-border-radius:                   $border-radius-base;
-$nav-pills-active-link-hover-bg:            $component-active-bg;
-$nav-pills-active-link-hover-color:         $component-active-color;
+$nav-pills-border-radius:                   $border-radius-base !default;
+$nav-pills-active-link-hover-bg:            $component-active-bg !default;
+$nav-pills-active-link-hover-color:         $component-active-color !default;
 
 
 //== Pagination
 //
 //##
 
-$pagination-color:                     $link-color;
-$pagination-bg:                        #fff;
-$pagination-border:                    #ddd;
+$pagination-color:                     $link-color !default;
+$pagination-bg:                        #fff !default;
+$pagination-border:                    #ddd !default;
 
-$pagination-hover-color:               $link-hover-color;
-$pagination-hover-bg:                  $gray-lighter;
-$pagination-hover-border:              #ddd;
+$pagination-hover-color:               $link-hover-color !default;
+$pagination-hover-bg:                  $gray-lighter !default;
+$pagination-hover-border:              #ddd !default;
 
-$pagination-active-color:              #fff;
-$pagination-active-bg:                 $brand-primary;
-$pagination-active-border:             $brand-primary;
+$pagination-active-color:              #fff !default;
+$pagination-active-bg:                 $brand-primary !default;
+$pagination-active-border:             $brand-primary !default;
 
-$pagination-disabled-color:            $gray-light;
-$pagination-disabled-bg:               #fff;
-$pagination-disabled-border:           #ddd;
+$pagination-disabled-color:            $gray-light !default;
+$pagination-disabled-bg:               #fff !default;
+$pagination-disabled-border:           #ddd !default;
 
 
 //== Pager
 //
 //##
 
-$pager-bg:                             $pagination-bg;
-$pager-border:                         $pagination-border;
-$pager-border-radius:                  15px;
+$pager-bg:                             $pagination-bg !default;
+$pager-border:                         $pagination-border !default;
+$pager-border-radius:                  15px !default;
 
-$pager-hover-bg:                       $pagination-hover-bg;
+$pager-hover-bg:                       $pagination-hover-bg !default;
 
-$pager-active-bg:                      $pagination-active-bg;
-$pager-active-color:                   $pagination-active-color;
+$pager-active-bg:                      $pagination-active-bg !default;
+$pager-active-color:                   $pagination-active-color !default;
 
-$pager-disabled-color:                 $pagination-disabled-color;
+$pager-disabled-color:                 $pagination-disabled-color !default;
 
 
 //== Jumbotron
 //
 //##
 
-$jumbotron-padding:              30px;
-$jumbotron-color:                inherit;
-$jumbotron-bg:                   $gray-lighter;
-$jumbotron-heading-color:        inherit;
-$jumbotron-font-size:            ceil(($font-size-base * 1.5));
+$jumbotron-padding:              30px !default;
+$jumbotron-color:                inherit !default;
+$jumbotron-bg:                   $gray-lighter !default;
+$jumbotron-heading-color:        inherit !default;
+$jumbotron-font-size:            ceil(($font-size-base * 1.5)) !default;
 
 
 //== Form states and alerts
 //
 //## Define colors for form feedback states and, by default, alerts.
 
-$state-success-text:             #3c763d;
-$state-success-bg:               #dff0d8;
-$state-success-border:           darken(adjust-hue($state-success-bg, -10), 5%);
+$state-success-text:             #3c763d !default;
+$state-success-bg:               #dff0d8 !default;
+$state-success-border:           darken(adjust-hue($state-success-bg, -10), 5%) !default;
 
-$state-info-text:                #31708f;
-$state-info-bg:                  #d9edf7;
-$state-info-border:              darken(adjust-hue($state-info-bg, -10), 7%);
+$state-info-text:                #31708f !default;
+$state-info-bg:                  #d9edf7 !default;
+$state-info-border:              darken(adjust-hue($state-info-bg, -10), 7%) !default;
 
-$state-warning-text:             #8a6d3b;
-$state-warning-bg:               #fcf8e3;
-$state-warning-border:           darken(adjust-hue($state-warning-bg, -10), 5%);
+$state-warning-text:             #8a6d3b !default;
+$state-warning-bg:               #fcf8e3 !default;
+$state-warning-border:           darken(adjust-hue($state-warning-bg, -10), 5%) !default;
 
-$state-danger-text:              #a94442;
-$state-danger-bg:                #f2dede;
-$state-danger-border:            darken(adjust-hue($state-danger-bg, -10), 5%);
+$state-danger-text:              #a94442 !default;
+$state-danger-bg:                #f2dede !default;
+$state-danger-border:            darken(adjust-hue($state-danger-bg, -10), 5%) !default;
 
 
 //== Tooltips
@@ -512,17 +512,17 @@ $state-danger-border:            darken(adjust-hue($state-danger-bg, -10), 5%);
 //##
 
 //** Tooltip max width
-$tooltip-max-width:           200px;
+$tooltip-max-width:           200px !default;
 //** Tooltip text color
-$tooltip-color:               #fff;
+$tooltip-color:               #fff !default;
 //** Tooltip background color
-$tooltip-bg:                  #000;
-$tooltip-opacity:             .9;
+$tooltip-bg:                  #000 !default;
+$tooltip-opacity:             .9 !default;
 
 //** Tooltip arrow width
-$tooltip-arrow-width:         5px;
+$tooltip-arrow-width:         5px !default;
 //** Tooltip arrow color
-$tooltip-arrow-color:         $tooltip-bg;
+$tooltip-arrow-color:         $tooltip-bg !default;
 
 
 //== Popovers
@@ -530,28 +530,28 @@ $tooltip-arrow-color:         $tooltip-bg;
 //##
 
 //** Popover body background color
-$popover-bg:                          #fff;
+$popover-bg:                          #fff !default;
 //** Popover maximum width
-$popover-max-width:                   276px;
+$popover-max-width:                   276px !default;
 //** Popover border color
-$popover-border-color:                rgba(0,0,0,.2);
+$popover-border-color:                rgba(0,0,0,.2) !default;
 //** Popover fallback border color
-$popover-fallback-border-color:       #ccc;
+$popover-fallback-border-color:       #ccc !default;
 
 //** Popover title background color
-$popover-title-bg:                    darken($popover-bg, 3%);
+$popover-title-bg:                    darken($popover-bg, 3%) !default;
 
 //** Popover arrow width
-$popover-arrow-width:                 10px;
+$popover-arrow-width:                 10px !default;
 //** Popover arrow color
-$popover-arrow-color:                 $popover-bg;
+$popover-arrow-color:                 $popover-bg !default;
 
 //** Popover outer arrow width
-$popover-arrow-outer-width:           ($popover-arrow-width + 1);
+$popover-arrow-outer-width:           ($popover-arrow-width + 1) !default;
 //** Popover outer arrow color
-$popover-arrow-outer-color:           fadein($popover-border-color, 5%);
+$popover-arrow-outer-color:           fadein($popover-border-color, 5%) !default;
 //** Popover outer arrow fallback color
-$popover-arrow-outer-fallback-color:  darken($popover-fallback-border-color, 20%);
+$popover-arrow-outer-fallback-color:  darken($popover-fallback-border-color, 20%) !default;
 
 
 //== Labels
@@ -559,22 +559,22 @@ $popover-arrow-outer-fallback-color:  darken($popover-fallback-border-color, 20%
 //##
 
 //** Default label background color
-$label-default-bg:            $gray-light;
+$label-default-bg:            $gray-light !default;
 //** Primary label background color
-$label-primary-bg:            $brand-primary;
+$label-primary-bg:            $brand-primary !default;
 //** Success label background color
-$label-success-bg:            $brand-success;
+$label-success-bg:            $brand-success !default;
 //** Info label background color
-$label-info-bg:               $brand-info;
+$label-info-bg:               $brand-info !default;
 //** Warning label background color
-$label-warning-bg:            $brand-warning;
+$label-warning-bg:            $brand-warning !default;
 //** Danger label background color
-$label-danger-bg:             $brand-danger;
+$label-danger-bg:             $brand-danger !default;
 
 //** Default label text color
-$label-color:                 #fff;
+$label-color:                 #fff !default;
 //** Default text color of a linked label
-$label-link-hover-color:      #fff;
+$label-link-hover-color:      #fff !default;
 
 
 //== Modals
@@ -582,57 +582,57 @@ $label-link-hover-color:      #fff;
 //##
 
 //** Padding applied to the modal body
-$modal-inner-padding:         15px;
+$modal-inner-padding:         15px !default;
 
 //** Padding applied to the modal title
-$modal-title-padding:         15px;
+$modal-title-padding:         15px !default;
 //** Modal title line-height
-$modal-title-line-height:     $line-height-base;
+$modal-title-line-height:     $line-height-base !default;
 
 //** Background color of modal content area
-$modal-content-bg:                             #fff;
+$modal-content-bg:                             #fff !default;
 //** Modal content border color
-$modal-content-border-color:                   rgba(0,0,0,.2);
+$modal-content-border-color:                   rgba(0,0,0,.2) !default;
 //** Modal content border color **for IE8**
-$modal-content-fallback-border-color:          #999;
+$modal-content-fallback-border-color:          #999 !default;
 
 //** Modal backdrop background color
-$modal-backdrop-bg:           #000;
+$modal-backdrop-bg:           #000 !default;
 //** Modal backdrop opacity
-$modal-backdrop-opacity:      .5;
+$modal-backdrop-opacity:      .5 !default;
 //** Modal header border color
-$modal-header-border-color:   #e5e5e5;
+$modal-header-border-color:   #e5e5e5 !default;
 //** Modal footer border color
-$modal-footer-border-color:   $modal-header-border-color;
+$modal-footer-border-color:   $modal-header-border-color !default;
 
-$modal-lg:                    900px;
-$modal-md:                    600px;
-$modal-sm:                    300px;
+$modal-lg:                    900px !default;
+$modal-md:                    600px !default;
+$modal-sm:                    300px !default;
 
 
 //== Alerts
 //
 //## Define alert colors, border radius, and padding.
 
-$alert-padding:               15px;
-$alert-border-radius:         $border-radius-base;
-$alert-link-font-weight:      bold;
+$alert-padding:               15px !default;
+$alert-border-radius:         $border-radius-base !default;
+$alert-link-font-weight:      bold !default;
 
-$alert-success-bg:            $state-success-bg;
-$alert-success-text:          $state-success-text;
-$alert-success-border:        $state-success-border;
+$alert-success-bg:            $state-success-bg !default;
+$alert-success-text:          $state-success-text !default;
+$alert-success-border:        $state-success-border !default;
 
-$alert-info-bg:               $state-info-bg;
-$alert-info-text:             $state-info-text;
-$alert-info-border:           $state-info-border;
+$alert-info-bg:               $state-info-bg !default;
+$alert-info-text:             $state-info-text !default;
+$alert-info-border:           $state-info-border !default;
 
-$alert-warning-bg:            $state-warning-bg;
-$alert-warning-text:          $state-warning-text;
-$alert-warning-border:        $state-warning-border;
+$alert-warning-bg:            $state-warning-bg !default;
+$alert-warning-text:          $state-warning-text !default;
+$alert-warning-border:        $state-warning-border !default;
 
-$alert-danger-bg:             $state-danger-bg;
-$alert-danger-text:           $state-danger-text;
-$alert-danger-border:         $state-danger-border;
+$alert-danger-bg:             $state-danger-bg !default;
+$alert-danger-text:           $state-danger-text !default;
+$alert-danger-border:         $state-danger-border !default;
 
 
 //== Progress bars
@@ -640,22 +640,22 @@ $alert-danger-border:         $state-danger-border;
 //##
 
 //** Background color of the whole progress component
-$progress-bg:                 #f5f5f5;
+$progress-bg:                 #f5f5f5 !default;
 //** Progress bar text color
-$progress-bar-color:          #fff;
+$progress-bar-color:          #fff !default;
 //** Variable for setting rounded corners on progress bar.
-$progress-border-radius:      $border-radius-base;
+$progress-border-radius:      $border-radius-base !default;
 
 //** Default progress bar color
-$progress-bar-bg:             $brand-primary;
+$progress-bar-bg:             $brand-primary !default;
 //** Success progress bar color
-$progress-bar-success-bg:     $brand-success;
+$progress-bar-success-bg:     $brand-success !default;
 //** Warning progress bar color
-$progress-bar-warning-bg:     $brand-warning;
+$progress-bar-warning-bg:     $brand-warning !default;
 //** Danger progress bar color
-$progress-bar-danger-bg:      $brand-danger;
+$progress-bar-danger-bg:      $brand-danger !default;
 //** Info progress bar color
-$progress-bar-info-bg:        $brand-info;
+$progress-bar-info-bg:        $brand-info !default;
 
 
 //== List group
@@ -663,72 +663,72 @@ $progress-bar-info-bg:        $brand-info;
 //##
 
 //** Background color on `.list-group-item`
-$list-group-bg:                 #fff;
+$list-group-bg:                 #fff !default;
 //** `.list-group-item` border color
-$list-group-border:             #ddd;
+$list-group-border:             #ddd !default;
 //** List group border radius
-$list-group-border-radius:      $border-radius-base;
+$list-group-border-radius:      $border-radius-base !default;
 
 //** Background color of single list items on hover
-$list-group-hover-bg:           #f5f5f5;
+$list-group-hover-bg:           #f5f5f5 !default;
 //** Text color of active list items
-$list-group-active-color:       $component-active-color;
+$list-group-active-color:       $component-active-color !default;
 //** Background color of active list items
-$list-group-active-bg:          $component-active-bg;
+$list-group-active-bg:          $component-active-bg !default;
 //** Border color of active list elements
-$list-group-active-border:      $list-group-active-bg;
+$list-group-active-border:      $list-group-active-bg !default;
 //** Text color for content within active list items
-$list-group-active-text-color:  lighten($list-group-active-bg, 40%);
+$list-group-active-text-color:  lighten($list-group-active-bg, 40%) !default;
 
 //** Text color of disabled list items
-$list-group-disabled-color:      $gray-light;
+$list-group-disabled-color:      $gray-light !default;
 //** Background color of disabled list items
-$list-group-disabled-bg:         $gray-lighter;
+$list-group-disabled-bg:         $gray-lighter !default;
 //** Text color for content within disabled list items
-$list-group-disabled-text-color: $list-group-disabled-color;
+$list-group-disabled-text-color: $list-group-disabled-color !default;
 
-$list-group-link-color:         #555;
-$list-group-link-hover-color:   $list-group-link-color;
-$list-group-link-heading-color: #333;
+$list-group-link-color:         #555 !default;
+$list-group-link-hover-color:   $list-group-link-color !default;
+$list-group-link-heading-color: #333 !default;
 
 
 //== Panels
 //
 //##
 
-$panel-bg:                    #fff;
-$panel-body-padding:          15px;
-$panel-heading-padding:       10px 15px;
-$panel-footer-padding:        $panel-heading-padding;
-$panel-border-radius:         $border-radius-base;
+$panel-bg:                    #fff !default;
+$panel-body-padding:          15px !default;
+$panel-heading-padding:       10px 15px !default;
+$panel-footer-padding:        $panel-heading-padding !default;
+$panel-border-radius:         $border-radius-base !default;
 
 //** Border color for elements within panels
-$panel-inner-border:          #ddd;
-$panel-footer-bg:             #f5f5f5;
+$panel-inner-border:          #ddd !default;
+$panel-footer-bg:             #f5f5f5 !default;
 
-$panel-default-text:          $gray-dark;
-$panel-default-border:        #ddd;
-$panel-default-heading-bg:    #f5f5f5;
+$panel-default-text:          $gray-dark !default;
+$panel-default-border:        #ddd !default;
+$panel-default-heading-bg:    #f5f5f5 !default;
 
-$panel-primary-text:          #fff;
-$panel-primary-border:        $brand-primary;
-$panel-primary-heading-bg:    $brand-primary;
+$panel-primary-text:          #fff !default;
+$panel-primary-border:        $brand-primary !default;
+$panel-primary-heading-bg:    $brand-primary !default;
 
-$panel-success-text:          $state-success-text;
-$panel-success-border:        $state-success-border;
-$panel-success-heading-bg:    $state-success-bg;
+$panel-success-text:          $state-success-text !default;
+$panel-success-border:        $state-success-border !default;
+$panel-success-heading-bg:    $state-success-bg !default;
 
-$panel-info-text:             $state-info-text;
-$panel-info-border:           $state-info-border;
-$panel-info-heading-bg:       $state-info-bg;
+$panel-info-text:             $state-info-text !default;
+$panel-info-border:           $state-info-border !default;
+$panel-info-heading-bg:       $state-info-bg !default;
 
-$panel-warning-text:          $state-warning-text;
-$panel-warning-border:        $state-warning-border;
-$panel-warning-heading-bg:    $state-warning-bg;
+$panel-warning-text:          $state-warning-text !default;
+$panel-warning-border:        $state-warning-border !default;
+$panel-warning-heading-bg:    $state-warning-bg !default;
 
-$panel-danger-text:           $state-danger-text;
-$panel-danger-border:         $state-danger-border;
-$panel-danger-heading-bg:     $state-danger-bg;
+$panel-danger-text:           $state-danger-text !default;
+$panel-danger-border:         $state-danger-border !default;
+$panel-danger-heading-bg:     $state-danger-bg !default;
 
 
 //== Thumbnails
@@ -736,103 +736,103 @@ $panel-danger-heading-bg:     $state-danger-bg;
 //##
 
 //** Padding around the thumbnail image
-$thumbnail-padding:           4px;
+$thumbnail-padding:           4px !default;
 //** Thumbnail background color
-$thumbnail-bg:                $body-bg;
+$thumbnail-bg:                $body-bg !default;
 //** Thumbnail border color
-$thumbnail-border:            #ddd;
+$thumbnail-border:            #ddd !default;
 //** Thumbnail border radius
-$thumbnail-border-radius:     $border-radius-base;
+$thumbnail-border-radius:     $border-radius-base !default;
 
 //** Custom text color for thumbnail captions
-$thumbnail-caption-color:     $text-color;
+$thumbnail-caption-color:     $text-color !default;
 //** Padding around the thumbnail caption
-$thumbnail-caption-padding:   9px;
+$thumbnail-caption-padding:   9px !default;
 
 
 //== Wells
 //
 //##
 
-$well-bg:                     #f5f5f5;
-$well-border:                 darken($well-bg, 7%);
+$well-bg:                     #f5f5f5 !default;
+$well-border:                 darken($well-bg, 7%) !default;
 
 
 //== Badges
 //
 //##
 
-$badge-color:                 #fff;
+$badge-color:                 #fff !default;
 //** Linked badge text color on hover
-$badge-link-hover-color:      #fff;
-$badge-bg:                    $gray-light;
+$badge-link-hover-color:      #fff !default;
+$badge-bg:                    $gray-light !default;
 
 //** Badge text color in active nav link
-$badge-active-color:          $link-color;
+$badge-active-color:          $link-color !default;
 //** Badge background color in active nav link
-$badge-active-bg:             #fff;
+$badge-active-bg:             #fff !default;
 
-$badge-font-weight:           bold;
-$badge-line-height:           1;
-$badge-border-radius:         10px;
+$badge-font-weight:           bold !default;
+$badge-line-height:           1 !default;
+$badge-border-radius:         10px !default;
 
 
 //== Breadcrumbs
 //
 //##
 
-$breadcrumb-padding-vertical:   8px;
-$breadcrumb-padding-horizontal: 15px;
+$breadcrumb-padding-vertical:   8px !default;
+$breadcrumb-padding-horizontal: 15px !default;
 //** Breadcrumb background color
-$breadcrumb-bg:                 #f5f5f5;
+$breadcrumb-bg:                 #f5f5f5 !default;
 //** Breadcrumb text color
-$breadcrumb-color:              #ccc;
+$breadcrumb-color:              #ccc !default;
 //** Text color of current page in the breadcrumb
-$breadcrumb-active-color:       $gray-light;
+$breadcrumb-active-color:       $gray-light !default;
 //** Textual separator for between breadcrumb elements
-$breadcrumb-separator:          "/";
+$breadcrumb-separator:          "/" !default;
 
 
 //== Carousel
 //
 //##
 
-$carousel-text-shadow:                        0 1px 2px rgba(0,0,0,.6);
+$carousel-text-shadow:                        0 1px 2px rgba(0,0,0,.6) !default;
 
-$carousel-control-color:                      #fff;
-$carousel-control-width:                      15%;
-$carousel-control-opacity:                    .5;
-$carousel-control-font-size:                  20px;
+$carousel-control-color:                      #fff !default;
+$carousel-control-width:                      15% !default;
+$carousel-control-opacity:                    .5 !default;
+$carousel-control-font-size:                  20px !default;
 
-$carousel-indicator-active-bg:                #fff;
-$carousel-indicator-border-color:             #fff;
+$carousel-indicator-active-bg:                #fff !default;
+$carousel-indicator-border-color:             #fff !default;
 
-$carousel-caption-color:                      #fff;
+$carousel-caption-color:                      #fff !default;
 
 
 //== Close
 //
 //##
 
-$close-font-weight:           bold;
-$close-color:                 #000;
-$close-text-shadow:           0 1px 0 #fff;
+$close-font-weight:           bold !default;
+$close-color:                 #000 !default;
+$close-text-shadow:           0 1px 0 #fff !default;
 
 
 //== Code
 //
 //##
 
-$code-color:                  #c7254e;
-$code-bg:                     #f9f2f4;
+$code-color:                  #c7254e !default;
+$code-bg:                     #f9f2f4 !default;
 
-$kbd-color:                   #fff;
-$kbd-bg:                      #333;
+$kbd-color:                   #fff !default;
+$kbd-bg:                      #333 !default;
 
-$pre-bg:                      #f5f5f5;
-$pre-color:                   $gray-dark;
-$pre-border-color:            #ccc;
-$pre-scrollable-max-height:   340px;
+$pre-bg:                      #f5f5f5 !default;
+$pre-color:                   $gray-dark !default;
+$pre-border-color:            #ccc !default;
+$pre-scrollable-max-height:   340px !default;
 
 
 //== Type
@@ -840,22 +840,22 @@ $pre-scrollable-max-height:   340px;
 //##
 
 //** Horizontal offset for forms and lists.
-$component-offset-horizontal: 180px;
+$component-offset-horizontal: 180px !default;
 //** Text muted color
-$text-muted:                  $gray-light;
+$text-muted:                  $gray-light !default;
 //** Abbreviations and acronyms border color
-$abbr-border-color:           $gray-light;
+$abbr-border-color:           $gray-light !default;
 //** Headings small color
-$headings-small-color:        $gray-light;
+$headings-small-color:        $gray-light !default;
 //** Blockquote small color
-$blockquote-small-color:      $gray-light;
+$blockquote-small-color:      $gray-light !default;
 //** Blockquote font size
-$blockquote-font-size:        ($font-size-base * 1.25);
+$blockquote-font-size:        ($font-size-base * 1.25) !default;
 //** Blockquote border color
-$blockquote-border-color:     $gray-lighter;
+$blockquote-border-color:     $gray-lighter !default;
 //** Page header border color
-$page-header-border-color:    $gray-lighter;
+$page-header-border-color:    $gray-lighter !default;
 //** Width of horizontal description list titles
-$dl-horizontal-offset:        $component-offset-horizontal;
+$dl-horizontal-offset:        $component-offset-horizontal !default;
 //** Horizontal line color.
-$hr-border:                   $gray-lighter;
+$hr-border:                   $gray-lighter !default;
diff --git a/cyborg/_variables.scss b/cyborg/_variables.scss
index 78322ce9..b071e0a3 100644
--- a/cyborg/_variables.scss
+++ b/cyborg/_variables.scss
@@ -7,18 +7,18 @@
 //
 //## Gray and brand colors for use across Bootstrap.
 
-$gray-base:              #000;
-$gray-darker:            #222; // #222
-$gray-dark:              #282828;   // #333
-$gray:                   #555; // #555
-$gray-light:             #888;   // #999
-$gray-lighter:           #ADAFAE; // #eee
+$gray-base:              #000 !default;
+$gray-darker:            #222 !default; // #222
+$gray-dark:              #282828 !default;   // #333
+$gray:                   #555 !default; // #555
+$gray-light:             #888 !default;   // #999
+$gray-lighter:           #ADAFAE !default; // #eee
 
-$brand-primary:         #2A9FD6;
-$brand-success:         #77B300;
-$brand-info:            #9933CC;
-$brand-warning:         #FF8800;
-$brand-danger:          #CC0000;
+$brand-primary:         #2A9FD6 !default;
+$brand-success:         #77B300 !default;
+$brand-info:            #9933CC !default;
+$brand-warning:         #FF8800 !default;
+$brand-danger:          #CC0000 !default;
 
 
 //== Scaffolding
@@ -26,49 +26,49 @@ $brand-danger:          #CC0000;
 //## Settings for some of the most global styles.
 
 //** Background color for ``.
-$body-bg:               #060606;
+$body-bg:               #060606 !default;
 //** Global text color on ``.
-$text-color:            $gray-light;
+$text-color:            $gray-light !default;
 
 //** Global textual link color.
-$link-color:            $brand-primary;
+$link-color:            $brand-primary !default;
 //** Link hover color set via `darken()` function.
-$link-hover-color:      $link-color;
+$link-hover-color:      $link-color !default;
 //** Link hover decoration.
-$link-hover-decoration: underline;
+$link-hover-decoration: underline !default;
 
 
 //== Typography
 //
 //## Font, line-height, and color for body text, headings, and more.
 
-$font-family-sans-serif:  "Roboto", "Helvetica Neue", Helvetica, Arial, sans-serif;
-$font-family-serif:       Georgia, "Times New Roman", Times, serif;
+$font-family-sans-serif:  "Roboto", "Helvetica Neue", Helvetica, Arial, sans-serif !default;
+$font-family-serif:       Georgia, "Times New Roman", Times, serif !default;
 //** Default monospace fonts for ``, ``, and `
`.
-$font-family-monospace:   Menlo, Monaco, Consolas, "Courier New", monospace;
-$font-family-base:        $font-family-sans-serif;
+$font-family-monospace:   Menlo, Monaco, Consolas, "Courier New", monospace !default;
+$font-family-base:        $font-family-sans-serif !default;
 
-$font-size-base:          14px;
-$font-size-large:         ceil(($font-size-base * 1.25)); // ~18px
-$font-size-small:         ceil(($font-size-base * 0.85)); // ~12px
+$font-size-base:          14px !default;
+$font-size-large:         ceil(($font-size-base * 1.25)) !default; // ~18px
+$font-size-small:         ceil(($font-size-base * 0.85)) !default; // ~12px
 
-$font-size-h1:            56px;
-$font-size-h2:            45px;
-$font-size-h3:            34px;
-$font-size-h4:            24px;
-$font-size-h5:            20px;
-$font-size-h6:            16px;
+$font-size-h1:            56px !default;
+$font-size-h2:            45px !default;
+$font-size-h3:            34px !default;
+$font-size-h4:            24px !default;
+$font-size-h5:            20px !default;
+$font-size-h6:            16px !default;
 
 //** Unit-less `line-height` for use in components like buttons.
-$line-height-base:        1.428571429; // 20/14
+$line-height-base:        1.428571429 !default; // 20/14
 //** Computed "line-height" (`font-size` * `line-height`) for use with `margin`, `padding`, etc.
-$line-height-computed:    floor(($font-size-base * $line-height-base)); // ~20px
+$line-height-computed:    floor(($font-size-base * $line-height-base)) !default; // ~20px
 
 //** By default, this inherits from the ``.
-$headings-font-family:    $font-family-base;
-$headings-font-weight:    500;
-$headings-line-height:    1.1;
-$headings-color:          #fff;
+$headings-font-family:    $font-family-base !default;
+$headings-font-weight:    500 !default;
+$headings-line-height:    1.1 !default;
+$headings-color:          #fff !default;
 
 
 //== Iconography
@@ -76,45 +76,45 @@ $headings-color:          #fff;
 //## Specify custom location and filename of the included Glyphicons icon font. Useful for those including Bootstrap via Bower.
 
 //** Load fonts from this directory.
-$icon-font-path:          "../fonts/";
+$icon-font-path:          "../fonts/" !default;
 //** File name for all font files.
-$icon-font-name:          "glyphicons-halflings-regular";
+$icon-font-name:          "glyphicons-halflings-regular" !default;
 //** Element ID within SVG icon file.
-$icon-font-svg-id:        "glyphicons_halflingsregular";
+$icon-font-svg-id:        "glyphicons_halflingsregular" !default;
 
 
 //== Components
 //
 //## Define common padding and border radius sizes and more. Values based on 14px text and 1.428 line-height (~20px to start).
 
-$padding-base-vertical:     8px;
-$padding-base-horizontal:   12px;
+$padding-base-vertical:     8px !default;
+$padding-base-horizontal:   12px !default;
 
-$padding-large-vertical:    14px;
-$padding-large-horizontal:  16px;
+$padding-large-vertical:    14px !default;
+$padding-large-horizontal:  16px !default;
 
-$padding-small-vertical:    5px;
-$padding-small-horizontal:  10px;
+$padding-small-vertical:    5px !default;
+$padding-small-horizontal:  10px !default;
 
-$padding-xs-vertical:       1px;
-$padding-xs-horizontal:     5px;
+$padding-xs-vertical:       1px !default;
+$padding-xs-horizontal:     5px !default;
 
-$line-height-large:         1.3333333; // extra decimals for Win 8.1 Chrome
-$line-height-small:         1.5;
+$line-height-large:         1.3333333 !default; // extra decimals for Win 8.1 Chrome
+$line-height-small:         1.5 !default;
 
-$border-radius-base:        4px;
-$border-radius-large:       6px;
-$border-radius-small:       3px;
+$border-radius-base:        4px !default;
+$border-radius-large:       6px !default;
+$border-radius-small:       3px !default;
 
 //** Global color for active items (e.g., navs or dropdowns).
-$component-active-color:    #fff;
+$component-active-color:    #fff !default;
 //** Global background color for active items (e.g., navs or dropdowns).
-$component-active-bg:       $brand-primary;
+$component-active-bg:       $brand-primary !default;
 
 //** Width of the `border` for generating carets that indicator dropdowns.
-$caret-width-base:          4px;
+$caret-width-base:          4px !default;
 //** Carets increase slightly in size for larger components.
-$caret-width-large:         5px;
+$caret-width-large:         5px !default;
 
 
 //== Tables
@@ -122,53 +122,53 @@ $caret-width-large:         5px;
 //## Customizes the `.table` component with basic values, each used across all table variations.
 
 //** Padding for ``s and ``s.
-$table-cell-padding:            8px;
+$table-cell-padding:            8px !default;
 //** Padding for cells in `.table-condensed`.
-$table-condensed-cell-padding:  5px;
+$table-condensed-cell-padding:  5px !default;
 
 //** Default background color used for all tables.
-$table-bg:                      darken($gray-darker, 4%);
+$table-bg:                      darken($gray-darker, 4%) !default;
 //** Background color used for `.table-striped`.
-$table-bg-accent:               darken($table-bg, 6%);
+$table-bg-accent:               darken($table-bg, 6%) !default;
 //** Background color used for `.table-hover`.
-$table-bg-hover:                $gray-dark;
-$table-bg-active:               $table-bg-hover;
+$table-bg-hover:                $gray-dark !default;
+$table-bg-active:               $table-bg-hover !default;
 
 //** Border color for table and cell borders.
-$table-border-color:            $gray-dark;
+$table-border-color:            $gray-dark !default;
 
 
 //== Buttons
 //
 //## For each of Bootstrap's buttons, define text, background and border color.
 
-$btn-font-weight:                normal;
+$btn-font-weight:                normal !default;
 
-$btn-default-color:              #fff;
-$btn-default-bg:                 lighten($gray-dark, 10%);
-$btn-default-border:             $btn-default-bg;
+$btn-default-color:              #fff !default;
+$btn-default-bg:                 lighten($gray-dark, 10%) !default;
+$btn-default-border:             $btn-default-bg !default;
 
-$btn-primary-color:              $btn-default-color;
-$btn-primary-bg:                 $brand-primary;
-$btn-primary-border:             $btn-primary-bg;
+$btn-primary-color:              $btn-default-color !default;
+$btn-primary-bg:                 $brand-primary !default;
+$btn-primary-border:             $btn-primary-bg !default;
 
-$btn-success-color:              $btn-default-color;
-$btn-success-bg:                 $brand-success;
-$btn-success-border:             $btn-success-bg;
+$btn-success-color:              $btn-default-color !default;
+$btn-success-bg:                 $brand-success !default;
+$btn-success-border:             $btn-success-bg !default;
 
-$btn-info-color:                 $btn-default-color;
-$btn-info-bg:                    $brand-info;
-$btn-info-border:                $btn-info-bg;
+$btn-info-color:                 $btn-default-color !default;
+$btn-info-bg:                    $brand-info !default;
+$btn-info-border:                $btn-info-bg !default;
 
-$btn-warning-color:              $btn-default-color;
-$btn-warning-bg:                 $brand-warning;
-$btn-warning-border:             $btn-warning-bg;
+$btn-warning-color:              $btn-default-color !default;
+$btn-warning-bg:                 $brand-warning !default;
+$btn-warning-border:             $btn-warning-bg !default;
 
-$btn-danger-color:               $btn-default-color;
-$btn-danger-bg:                  $brand-danger;
-$btn-danger-border:              $btn-danger-bg;
+$btn-danger-color:               $btn-default-color !default;
+$btn-danger-bg:                  $brand-danger !default;
+$btn-danger-border:              $btn-danger-bg !default;
 
-$btn-link-disabled-color:        $gray-light;
+$btn-link-disabled-color:        $gray-light !default;
 
 
 //== Forms
@@ -176,50 +176,50 @@ $btn-link-disabled-color:        $gray-light;
 //##
 
 //** `` background color
-$input-bg:                       #fff;
+$input-bg:                       #fff !default;
 //** `` background color
-$input-bg-disabled:              $gray-lighter;
+$input-bg-disabled:              $gray-lighter !default;
 
 //** Text color for ``s
-$input-color:                    $text-color;
+$input-color:                    $text-color !default;
 //** `` border color
-$input-border:                   $gray-dark;
+$input-border:                   $gray-dark !default;
 
 // TODO: Rename `$input-border-radius` to `$input-border-radius-base` in v4
 //** Default `.form-control` border radius
 // This has no effect on ``s in CSS.
-$input-border-radius:            $border-radius-base;
+$input-border-radius:            $border-radius-base !default;
 //** Large `.form-control` border radius
-$input-border-radius-large:      $border-radius-large;
+$input-border-radius-large:      $border-radius-large !default;
 //** Small `.form-control` border radius
-$input-border-radius-small:      $border-radius-small;
+$input-border-radius-small:      $border-radius-small !default;
 
 //** Border color for inputs on focus
-$input-border-focus:             #66afe9;
+$input-border-focus:             #66afe9 !default;
 
 //** Placeholder text color
-$input-color-placeholder:        $gray-light;
+$input-color-placeholder:        $gray-light !default;
 
 //** Default `.form-control` height
-$input-height-base:              ($line-height-computed + ($padding-base-vertical * 2) + 2);
+$input-height-base:              ($line-height-computed + ($padding-base-vertical * 2) + 2) !default;
 //** Large `.form-control` height
-$input-height-large:             (ceil($font-size-large * $line-height-large) + ($padding-large-vertical * 2) + 2);
+$input-height-large:             (ceil($font-size-large * $line-height-large) + ($padding-large-vertical * 2) + 2) !default;
 //** Small `.form-control` height
-$input-height-small:             (floor($font-size-small * $line-height-small) + ($padding-small-vertical * 2) + 2);
+$input-height-small:             (floor($font-size-small * $line-height-small) + ($padding-small-vertical * 2) + 2) !default;
 
 //** `.form-group` margin
-$form-group-margin-bottom:       15px;
+$form-group-margin-bottom:       15px !default;
 
-$legend-color:                   $text-color;
-$legend-border-color:            $gray-dark;
+$legend-color:                   $text-color !default;
+$legend-border-color:            $gray-dark !default;
 
 //** Background color for textual input addons
-$input-group-addon-bg:           $gray-lighter;
+$input-group-addon-bg:           $gray-lighter !default;
 //** Border color for textual input addons
-$input-group-addon-border-color: $input-border;
+$input-group-addon-border-color: $input-border !default;
 
 //** Disabled cursor for form controls and buttons.
-$cursor-disabled:                not-allowed;
+$cursor-disabled:                not-allowed !default;
 
 
 //== Dropdowns
@@ -227,34 +227,34 @@ $cursor-disabled:                not-allowed;
 //## Dropdown menu container and contents.
 
 //** Background for the dropdown menu.
-$dropdown-bg:                    $gray-darker;
+$dropdown-bg:                    $gray-darker !default;
 //** Dropdown menu `border-color`.
-$dropdown-border:                rgba(255,255,255,0.1);
+$dropdown-border:                rgba(255,255,255,0.1) !default;
 //** Dropdown menu `border-color` **for IE8**.
-$dropdown-fallback-border:       #444;
+$dropdown-fallback-border:       #444 !default;
 //** Divider color for between dropdown items.
-$dropdown-divider-bg:            rgba(255,255,255,0.1);
+$dropdown-divider-bg:            rgba(255,255,255,0.1) !default;
 
 //** Dropdown link text color.
-$dropdown-link-color:            #fff;
+$dropdown-link-color:            #fff !default;
 //** Hover color for dropdown links.
-$dropdown-link-hover-color:      #fff;
+$dropdown-link-hover-color:      #fff !default;
 //** Hover background for dropdown links.
-$dropdown-link-hover-bg:         $component-active-bg;
+$dropdown-link-hover-bg:         $component-active-bg !default;
 
 //** Active dropdown menu item text color.
-$dropdown-link-active-color:     #fff;
+$dropdown-link-active-color:     #fff !default;
 //** Active dropdown menu item background color.
-$dropdown-link-active-bg:        $component-active-bg;
+$dropdown-link-active-bg:        $component-active-bg !default;
 
 //** Disabled dropdown menu item background color.
-$dropdown-link-disabled-color:   $gray-light;
+$dropdown-link-disabled-color:   $gray-light !default;
 
 //** Text color for headers within dropdown menus.
-$dropdown-header-color:          $gray-light;
+$dropdown-header-color:          $gray-light !default;
 
 //** Deprecated `$dropdown-caret-color` as of v3.1.0
-$dropdown-caret-color:           #000;
+$dropdown-caret-color:           #000 !default;
 
 
 //-- Z-index master list
@@ -264,13 +264,13 @@ $dropdown-caret-color:           #000;
 //
 // Note: These variables are not generated into the Customizer.
 
-$zindex-navbar:            1000;
-$zindex-dropdown:          1000;
-$zindex-popover:           1060;
-$zindex-tooltip:           1070;
-$zindex-navbar-fixed:      1030;
-$zindex-modal-background:  1040;
-$zindex-modal:             1050;
+$zindex-navbar:            1000 !default;
+$zindex-dropdown:          1000 !default;
+$zindex-popover:           1060 !default;
+$zindex-tooltip:           1070 !default;
+$zindex-navbar-fixed:      1030 !default;
+$zindex-modal-background:  1040 !default;
+$zindex-modal:             1050 !default;
 
 
 //== Media queries breakpoints
@@ -279,37 +279,37 @@ $zindex-modal:             1050;
 
 // Extra small screen / phone
 //** Deprecated `$screen-xs` as of v3.0.1
-$screen-xs:                  480px;
+$screen-xs:                  480px !default;
 //** Deprecated `$screen-xs-min` as of v3.2.0
-$screen-xs-min:              $screen-xs;
+$screen-xs-min:              $screen-xs !default;
 //** Deprecated `$screen-phone` as of v3.0.1
-$screen-phone:               $screen-xs-min;
+$screen-phone:               $screen-xs-min !default;
 
 // Small screen / tablet
 //** Deprecated `$screen-sm` as of v3.0.1
-$screen-sm:                  768px;
-$screen-sm-min:              $screen-sm;
+$screen-sm:                  768px !default;
+$screen-sm-min:              $screen-sm !default;
 //** Deprecated `$screen-tablet` as of v3.0.1
-$screen-tablet:              $screen-sm-min;
+$screen-tablet:              $screen-sm-min !default;
 
 // Medium screen / desktop
 //** Deprecated `$screen-md` as of v3.0.1
-$screen-md:                  992px;
-$screen-md-min:              $screen-md;
+$screen-md:                  992px !default;
+$screen-md-min:              $screen-md !default;
 //** Deprecated `$screen-desktop` as of v3.0.1
-$screen-desktop:             $screen-md-min;
+$screen-desktop:             $screen-md-min !default;
 
 // Large screen / wide desktop
 //** Deprecated `$screen-lg` as of v3.0.1
-$screen-lg:                  1200px;
-$screen-lg-min:              $screen-lg;
+$screen-lg:                  1200px !default;
+$screen-lg-min:              $screen-lg !default;
 //** Deprecated `$screen-lg-desktop` as of v3.0.1
-$screen-lg-desktop:          $screen-lg-min;
+$screen-lg-desktop:          $screen-lg-min !default;
 
 // So media queries don't overlap when required, provide a maximum
-$screen-xs-max:              ($screen-sm-min - 1);
-$screen-sm-max:              ($screen-md-min - 1);
-$screen-md-max:              ($screen-lg-min - 1);
+$screen-xs-max:              ($screen-sm-min - 1) !default;
+$screen-sm-max:              ($screen-md-min - 1) !default;
+$screen-md-max:              ($screen-lg-min - 1) !default;
 
 
 //== Grid system
@@ -317,14 +317,14 @@ $screen-md-max:              ($screen-lg-min - 1);
 //## Define your custom responsive grid.
 
 //** Number of columns in the grid.
-$grid-columns:              12;
+$grid-columns:              12 !default;
 //** Padding between columns. Gets divided in half for the left and right.
-$grid-gutter-width:         30px;
+$grid-gutter-width:         30px !default;
 // Navbar collapse
 //** Point at which the navbar becomes uncollapsed.
-$grid-float-breakpoint:     $screen-sm-min;
+$grid-float-breakpoint:     $screen-sm-min !default;
 //** Point at which the navbar begins collapsing.
-$grid-float-breakpoint-max: ($grid-float-breakpoint - 1);
+$grid-float-breakpoint-max: ($grid-float-breakpoint - 1) !default;
 
 
 //== Container sizes
@@ -332,19 +332,19 @@ $grid-float-breakpoint-max: ($grid-float-breakpoint - 1);
 //## Define the maximum width of `.container` for different screen sizes.
 
 // Small screen / tablet
-$container-tablet:             (720px + $grid-gutter-width);
+$container-tablet:             (720px + $grid-gutter-width) !default;
 //** For `$screen-sm-min` and up.
-$container-sm:                 $container-tablet;
+$container-sm:                 $container-tablet !default;
 
 // Medium screen / desktop
-$container-desktop:            (940px + $grid-gutter-width);
+$container-desktop:            (940px + $grid-gutter-width) !default;
 //** For `$screen-md-min` and up.
-$container-md:                 $container-desktop;
+$container-md:                 $container-desktop !default;
 
 // Large screen / wide desktop
-$container-large-desktop:      (1140px + $grid-gutter-width);
+$container-large-desktop:      (1140px + $grid-gutter-width) !default;
 //** For `$screen-lg-min` and up.
-$container-lg:                 $container-large-desktop;
+$container-lg:                 $container-large-desktop !default;
 
 
 //== Navbar
@@ -352,61 +352,61 @@ $container-lg:                 $container-large-desktop;
 //##
 
 // Basics of a navbar
-$navbar-height:                    50px;
-$navbar-margin-bottom:             $line-height-computed;
-$navbar-border-radius:             $border-radius-base;
-$navbar-padding-horizontal:        floor(($grid-gutter-width / 2));
-$navbar-padding-vertical:          (($navbar-height - $line-height-computed) / 2);
-$navbar-collapse-max-height:       340px;
+$navbar-height:                    50px !default;
+$navbar-margin-bottom:             $line-height-computed !default;
+$navbar-border-radius:             $border-radius-base !default;
+$navbar-padding-horizontal:        floor(($grid-gutter-width / 2)) !default;
+$navbar-padding-vertical:          (($navbar-height - $line-height-computed) / 2) !default;
+$navbar-collapse-max-height:       340px !default;
 
-$navbar-default-color:             $text-color;
-$navbar-default-bg:                $body-bg;
-$navbar-default-border:            $gray-dark;
+$navbar-default-color:             $text-color !default;
+$navbar-default-bg:                $body-bg !default;
+$navbar-default-border:            $gray-dark !default;
 
 // Navbar links
-$navbar-default-link-color:                $text-color;
-$navbar-default-link-hover-color:          #fff;
-$navbar-default-link-hover-bg:             transparent;
-$navbar-default-link-active-color:         #fff;
-$navbar-default-link-active-bg:            transparent;
-$navbar-default-link-disabled-color:       $gray-light;
-$navbar-default-link-disabled-bg:          transparent;
+$navbar-default-link-color:                $text-color !default;
+$navbar-default-link-hover-color:          #fff !default;
+$navbar-default-link-hover-bg:             transparent !default;
+$navbar-default-link-active-color:         #fff !default;
+$navbar-default-link-active-bg:            transparent !default;
+$navbar-default-link-disabled-color:       $gray-light !default;
+$navbar-default-link-disabled-bg:          transparent !default;
 
 // Navbar brand label
-$navbar-default-brand-color:               #fff;
-$navbar-default-brand-hover-color:         #fff;
-$navbar-default-brand-hover-bg:            transparent;
+$navbar-default-brand-color:               #fff !default;
+$navbar-default-brand-hover-color:         #fff !default;
+$navbar-default-brand-hover-bg:            transparent !default;
 
 // Navbar toggle
-$navbar-default-toggle-hover-bg:           $gray-dark;
-$navbar-default-toggle-icon-bar-bg:        #ccc;
-$navbar-default-toggle-border-color:       $gray-dark;
+$navbar-default-toggle-hover-bg:           $gray-dark !default;
+$navbar-default-toggle-icon-bar-bg:        #ccc !default;
+$navbar-default-toggle-border-color:       $gray-dark !default;
 
 
 // Inverted navbar
 // Reset inverted navbar basics
-$navbar-inverse-color:                      $gray-light;
-$navbar-inverse-bg:                         $gray-darker;
-$navbar-inverse-border:                     darken($navbar-inverse-bg, 10%);
+$navbar-inverse-color:                      $gray-light !default;
+$navbar-inverse-bg:                         $gray-darker !default;
+$navbar-inverse-border:                     darken($navbar-inverse-bg, 10%) !default;
 
 // Inverted navbar links
-$navbar-inverse-link-color:                 $gray-light;
-$navbar-inverse-link-hover-color:           #fff;
-$navbar-inverse-link-hover-bg:              transparent;
-$navbar-inverse-link-active-color:          $navbar-inverse-link-hover-color;
-$navbar-inverse-link-active-bg:             transparent;
-$navbar-inverse-link-disabled-color:        #aaa;
-$navbar-inverse-link-disabled-bg:           transparent;
+$navbar-inverse-link-color:                 $gray-light !default;
+$navbar-inverse-link-hover-color:           #fff !default;
+$navbar-inverse-link-hover-bg:              transparent !default;
+$navbar-inverse-link-active-color:          $navbar-inverse-link-hover-color !default;
+$navbar-inverse-link-active-bg:             transparent !default;
+$navbar-inverse-link-disabled-color:        #aaa !default;
+$navbar-inverse-link-disabled-bg:           transparent !default;
 
 // Inverted navbar brand label
-$navbar-inverse-brand-color:                #fff;
-$navbar-inverse-brand-hover-color:          #fff;
-$navbar-inverse-brand-hover-bg:             transparent;
+$navbar-inverse-brand-color:                #fff !default;
+$navbar-inverse-brand-hover-color:          #fff !default;
+$navbar-inverse-brand-hover-bg:             transparent !default;
 
 // Inverted navbar toggle
-$navbar-inverse-toggle-hover-bg:            #333;
-$navbar-inverse-toggle-icon-bar-bg:         #fff;
-$navbar-inverse-toggle-border-color:        #333;
+$navbar-inverse-toggle-hover-bg:            #333 !default;
+$navbar-inverse-toggle-icon-bar-bg:         #fff !default;
+$navbar-inverse-toggle-border-color:        #333 !default;
 
 
 //== Navs
@@ -414,97 +414,97 @@ $navbar-inverse-toggle-border-color:        #333;
 //##
 
 //=== Shared nav styles
-$nav-link-padding:                          10px 15px;
-$nav-link-hover-bg:                         $gray-darker;
+$nav-link-padding:                          10px 15px !default;
+$nav-link-hover-bg:                         $gray-darker !default;
 
-$nav-disabled-link-color:                   $gray-light;
-$nav-disabled-link-hover-color:             $gray-light;
+$nav-disabled-link-color:                   $gray-light !default;
+$nav-disabled-link-hover-color:             $gray-light !default;
 
 //== Tabs
-$nav-tabs-border-color:                     $gray-dark;
+$nav-tabs-border-color:                     $gray-dark !default;
 
-$nav-tabs-link-hover-border-color:          transparent;
+$nav-tabs-link-hover-border-color:          transparent !default;
 
-$nav-tabs-active-link-hover-bg:             $brand-primary;
-$nav-tabs-active-link-hover-color:          #fff;
-$nav-tabs-active-link-hover-border-color:   $gray-dark;
+$nav-tabs-active-link-hover-bg:             $brand-primary !default;
+$nav-tabs-active-link-hover-color:          #fff !default;
+$nav-tabs-active-link-hover-border-color:   $gray-dark !default;
 
-$nav-tabs-justified-link-border-color:            #ddd;
-$nav-tabs-justified-active-link-border-color:     $body-bg;
+$nav-tabs-justified-link-border-color:            #ddd !default;
+$nav-tabs-justified-active-link-border-color:     $body-bg !default;
 
 //== Pills
-$nav-pills-border-radius:                   $border-radius-base;
-$nav-pills-active-link-hover-bg:            $component-active-bg;
-$nav-pills-active-link-hover-color:         $component-active-color;
+$nav-pills-border-radius:                   $border-radius-base !default;
+$nav-pills-active-link-hover-bg:            $component-active-bg !default;
+$nav-pills-active-link-hover-color:         $component-active-color !default;
 
 
 //== Pagination
 //
 //##
 
-$pagination-color:                     #fff;
-$pagination-bg:                        $gray-darker;
-$pagination-border:                    $gray-dark;
+$pagination-color:                     #fff !default;
+$pagination-bg:                        $gray-darker !default;
+$pagination-border:                    $gray-dark !default;
 
-$pagination-hover-color:               #fff;
-$pagination-hover-bg:                  $component-active-bg;
-$pagination-hover-border:              transparent;
+$pagination-hover-color:               #fff !default;
+$pagination-hover-bg:                  $component-active-bg !default;
+$pagination-hover-border:              transparent !default;
 
-$pagination-active-color:              #fff;
-$pagination-active-bg:                 $brand-primary;
-$pagination-active-border:             transparent;
+$pagination-active-color:              #fff !default;
+$pagination-active-bg:                 $brand-primary !default;
+$pagination-active-border:             transparent !default;
 
-$pagination-disabled-color:            $gray-light;
-$pagination-disabled-bg:               $gray-darker;
-$pagination-disabled-border:           $gray-dark;
+$pagination-disabled-color:            $gray-light !default;
+$pagination-disabled-bg:               $gray-darker !default;
+$pagination-disabled-border:           $gray-dark !default;
 
 
 //== Pager
 //
 //##
 
-$pager-bg:                             $pagination-bg;
-$pager-border:                         $pagination-border;
-$pager-border-radius:                  15px;
+$pager-bg:                             $pagination-bg !default;
+$pager-border:                         $pagination-border !default;
+$pager-border-radius:                  15px !default;
 
-$pager-hover-bg:                       $pagination-hover-bg;
+$pager-hover-bg:                       $pagination-hover-bg !default;
 
-$pager-active-bg:                      $pagination-active-bg;
-$pager-active-color:                   $pagination-active-color;
+$pager-active-bg:                      $pagination-active-bg !default;
+$pager-active-color:                   $pagination-active-color !default;
 
-$pager-disabled-color:                 $gray-light;
+$pager-disabled-color:                 $gray-light !default;
 
 
 //== Jumbotron
 //
 //##
 
-$jumbotron-padding:              30px;
-$jumbotron-color:                inherit;
-$jumbotron-bg:                   darken($gray-darker, 5%);
-$jumbotron-heading-color:        inherit;
-$jumbotron-font-size:            ceil(($font-size-base * 1.5));
+$jumbotron-padding:              30px !default;
+$jumbotron-color:                inherit !default;
+$jumbotron-bg:                   darken($gray-darker, 5%) !default;
+$jumbotron-heading-color:        inherit !default;
+$jumbotron-font-size:            ceil(($font-size-base * 1.5)) !default;
 
 
 //== Form states and alerts
 //
 //## Define colors for form feedback states and, by default, alerts.
 
-$state-success-text:             #fff;
-$state-success-bg:               $brand-success;
-$state-success-border:           darken(adjust-hue($state-success-bg, -10), 5%);
+$state-success-text:             #fff !default;
+$state-success-bg:               $brand-success !default;
+$state-success-border:           darken(adjust-hue($state-success-bg, -10), 5%) !default;
 
-$state-info-text:                #fff;
-$state-info-bg:                  $brand-info;
-$state-info-border:              darken(adjust-hue($state-info-bg, -10), 7%);
+$state-info-text:                #fff !default;
+$state-info-bg:                  $brand-info !default;
+$state-info-border:              darken(adjust-hue($state-info-bg, -10), 7%) !default;
 
-$state-warning-text:             #fff;
-$state-warning-bg:               $brand-warning;
-$state-warning-border:           darken(adjust-hue($state-warning-bg, -10), 3%);
+$state-warning-text:             #fff !default;
+$state-warning-bg:               $brand-warning !default;
+$state-warning-border:           darken(adjust-hue($state-warning-bg, -10), 3%) !default;
 
-$state-danger-text:              #fff;
-$state-danger-bg:                $brand-danger;
-$state-danger-border:            darken(adjust-hue($state-danger-bg, -10), 3%);
+$state-danger-text:              #fff !default;
+$state-danger-bg:                $brand-danger !default;
+$state-danger-border:            darken(adjust-hue($state-danger-bg, -10), 3%) !default;
 
 
 //== Tooltips
@@ -512,17 +512,17 @@ $state-danger-border:            darken(adjust-hue($state-danger-bg, -10), 3%);
 //##
 
 //** Tooltip max width
-$tooltip-max-width:           200px;
+$tooltip-max-width:           200px !default;
 //** Tooltip text color
-$tooltip-color:               #fff;
+$tooltip-color:               #fff !default;
 //** Tooltip background color
-$tooltip-bg:                  #000;
-$tooltip-opacity:             .9;
+$tooltip-bg:                  #000 !default;
+$tooltip-opacity:             .9 !default;
 
 //** Tooltip arrow width
-$tooltip-arrow-width:         5px;
+$tooltip-arrow-width:         5px !default;
 //** Tooltip arrow color
-$tooltip-arrow-color:         $tooltip-bg;
+$tooltip-arrow-color:         $tooltip-bg !default;
 
 
 //== Popovers
@@ -530,28 +530,28 @@ $tooltip-arrow-color:         $tooltip-bg;
 //##
 
 //** Popover body background color
-$popover-bg:                          lighten($body-bg, 10%);
+$popover-bg:                          lighten($body-bg, 10%) !default;
 //** Popover maximum width
-$popover-max-width:                   276px;
+$popover-max-width:                   276px !default;
 //** Popover border color
-$popover-border-color:                rgba(0,0,0,.2);
+$popover-border-color:                rgba(0,0,0,.2) !default;
 //** Popover fallback border color
-$popover-fallback-border-color:       #999;
+$popover-fallback-border-color:       #999 !default;
 
 //** Popover title background color
-$popover-title-bg:                    darken($popover-bg, 3%);
+$popover-title-bg:                    darken($popover-bg, 3%) !default;
 
 //** Popover arrow width
-$popover-arrow-width:                 10px;
+$popover-arrow-width:                 10px !default;
 //** Popover arrow color
-$popover-arrow-color:                 $popover-bg;
+$popover-arrow-color:                 $popover-bg !default;
 
 //** Popover outer arrow width
-$popover-arrow-outer-width:           ($popover-arrow-width + 1);
+$popover-arrow-outer-width:           ($popover-arrow-width + 1) !default;
 //** Popover outer arrow color
-$popover-arrow-outer-color:           fadein($popover-border-color, 5%);
+$popover-arrow-outer-color:           fadein($popover-border-color, 5%) !default;
 //** Popover outer arrow fallback color
-$popover-arrow-outer-fallback-color:  darken($popover-fallback-border-color, 20%);
+$popover-arrow-outer-fallback-color:  darken($popover-fallback-border-color, 20%) !default;
 
 
 //== Labels
@@ -559,22 +559,22 @@ $popover-arrow-outer-fallback-color:  darken($popover-fallback-border-color, 20%
 //##
 
 //** Default label background color
-$label-default-bg:            $btn-default-bg;
+$label-default-bg:            $btn-default-bg !default;
 //** Primary label background color
-$label-primary-bg:            $brand-primary;
+$label-primary-bg:            $brand-primary !default;
 //** Success label background color
-$label-success-bg:            $brand-success;
+$label-success-bg:            $brand-success !default;
 //** Info label background color
-$label-info-bg:               $brand-info;
+$label-info-bg:               $brand-info !default;
 //** Warning label background color
-$label-warning-bg:            $brand-warning;
+$label-warning-bg:            $brand-warning !default;
 //** Danger label background color
-$label-danger-bg:             $brand-danger;
+$label-danger-bg:             $brand-danger !default;
 
 //** Default label text color
-$label-color:                 #fff;
+$label-color:                 #fff !default;
 //** Default text color of a linked label
-$label-link-hover-color:      #fff;
+$label-link-hover-color:      #fff !default;
 
 
 //== Modals
@@ -582,57 +582,57 @@ $label-link-hover-color:      #fff;
 //##
 
 //** Padding applied to the modal body
-$modal-inner-padding:         20px;
+$modal-inner-padding:         20px !default;
 
 //** Padding applied to the modal title
-$modal-title-padding:         15px;
+$modal-title-padding:         15px !default;
 //** Modal title line-height
-$modal-title-line-height:     $line-height-base;
+$modal-title-line-height:     $line-height-base !default;
 
 //** Background color of modal content area
-$modal-content-bg:                             lighten($body-bg, 10%);
+$modal-content-bg:                             lighten($body-bg, 10%) !default;
 //** Modal content border color
-$modal-content-border-color:                   rgba(0,0,0,.2);
+$modal-content-border-color:                   rgba(0,0,0,.2) !default;
 //** Modal content border color **for IE8**
-$modal-content-fallback-border-color:          #999;
+$modal-content-fallback-border-color:          #999 !default;
 
 //** Modal backdrop background color
-$modal-backdrop-bg:           #000;
+$modal-backdrop-bg:           #000 !default;
 //** Modal backdrop opacity
-$modal-backdrop-opacity:      .5;
+$modal-backdrop-opacity:      .5 !default;
 //** Modal header border color
-$modal-header-border-color:   $gray-dark;
+$modal-header-border-color:   $gray-dark !default;
 //** Modal footer border color
-$modal-footer-border-color:   $modal-header-border-color;
+$modal-footer-border-color:   $modal-header-border-color !default;
 
-$modal-lg:                    900px;
-$modal-md:                    600px;
-$modal-sm:                    300px;
+$modal-lg:                    900px !default;
+$modal-md:                    600px !default;
+$modal-sm:                    300px !default;
 
 
 //== Alerts
 //
 //## Define alert colors, border radius, and padding.
 
-$alert-padding:               15px;
-$alert-border-radius:         $border-radius-base;
-$alert-link-font-weight:      bold;
+$alert-padding:               15px !default;
+$alert-border-radius:         $border-radius-base !default;
+$alert-link-font-weight:      bold !default;
 
-$alert-success-bg:            $state-success-bg;
-$alert-success-text:          $state-success-text;
-$alert-success-border:        $state-success-border;
+$alert-success-bg:            $state-success-bg !default;
+$alert-success-text:          $state-success-text !default;
+$alert-success-border:        $state-success-border !default;
 
-$alert-info-bg:               $state-info-bg;
-$alert-info-text:             $state-info-text;
-$alert-info-border:           $state-info-border;
+$alert-info-bg:               $state-info-bg !default;
+$alert-info-text:             $state-info-text !default;
+$alert-info-border:           $state-info-border !default;
 
-$alert-warning-bg:            $state-warning-bg;
-$alert-warning-text:          $state-warning-text;
-$alert-warning-border:        $state-warning-border;
+$alert-warning-bg:            $state-warning-bg !default;
+$alert-warning-text:          $state-warning-text !default;
+$alert-warning-border:        $state-warning-border !default;
 
-$alert-danger-bg:             $state-danger-bg;
-$alert-danger-text:           $state-danger-text;
-$alert-danger-border:         $state-danger-border;
+$alert-danger-bg:             $state-danger-bg !default;
+$alert-danger-text:           $state-danger-text !default;
+$alert-danger-border:         $state-danger-border !default;
 
 
 //== Progress bars
@@ -640,22 +640,22 @@ $alert-danger-border:         $state-danger-border;
 //##
 
 //** Background color of the whole progress component
-$progress-bg:                 $gray-darker;
+$progress-bg:                 $gray-darker !default;
 //** Progress bar text color
-$progress-bar-color:          #fff;
+$progress-bar-color:          #fff !default;
 //** Variable for setting rounded corners on progress bar.
-$progress-border-radius:      $border-radius-base;
+$progress-border-radius:      $border-radius-base !default;
 
 //** Default progress bar color
-$progress-bar-bg:             $brand-primary;
+$progress-bar-bg:             $brand-primary !default;
 //** Success progress bar color
-$progress-bar-success-bg:     $brand-success;
+$progress-bar-success-bg:     $brand-success !default;
 //** Warning progress bar color
-$progress-bar-warning-bg:     $brand-warning;
+$progress-bar-warning-bg:     $brand-warning !default;
 //** Danger progress bar color
-$progress-bar-danger-bg:      $brand-danger;
+$progress-bar-danger-bg:      $brand-danger !default;
 //** Info progress bar color
-$progress-bar-info-bg:        $brand-info;
+$progress-bar-info-bg:        $brand-info !default;
 
 
 //== List group
@@ -663,72 +663,72 @@ $progress-bar-info-bg:        $brand-info;
 //##
 
 //** Background color on `.list-group-item`
-$list-group-bg:                 $gray-darker;
+$list-group-bg:                 $gray-darker !default;
 //** `.list-group-item` border color
-$list-group-border:             $gray-dark;
+$list-group-border:             $gray-dark !default;
 //** List group border radius
-$list-group-border-radius:      $border-radius-base;
+$list-group-border-radius:      $border-radius-base !default;
 
 //** Background color of single list items on hover
-$list-group-hover-bg:           lighten($list-group-bg, 15%);
+$list-group-hover-bg:           lighten($list-group-bg, 15%) !default;
 //** Text color of active list items
-$list-group-active-color:       $component-active-color;
+$list-group-active-color:       $component-active-color !default;
 //** Background color of active list items
-$list-group-active-bg:          $component-active-bg;
+$list-group-active-bg:          $component-active-bg !default;
 //** Border color of active list elements
-$list-group-active-border:      $list-group-active-bg;
+$list-group-active-border:      $list-group-active-bg !default;
 //** Text color for content within active list items
-$list-group-active-text-color:  lighten($list-group-active-bg, 40%);
+$list-group-active-text-color:  lighten($list-group-active-bg, 40%) !default;
 
 //** Text color of disabled list items
-$list-group-disabled-color:      $gray-light;
+$list-group-disabled-color:      $gray-light !default;
 //** Background color of disabled list items
-$list-group-disabled-bg:         $gray-lighter;
+$list-group-disabled-bg:         $gray-lighter !default;
 //** Text color for content within disabled list items
-$list-group-disabled-text-color: $list-group-disabled-color;
+$list-group-disabled-text-color: $list-group-disabled-color !default;
 
-$list-group-link-color:         $text-color;
-$list-group-link-hover-color:   $list-group-link-color;
-$list-group-link-heading-color: #fff;
+$list-group-link-color:         $text-color !default;
+$list-group-link-hover-color:   $list-group-link-color !default;
+$list-group-link-heading-color: #fff !default;
 
 
 //== Panels
 //
 //##
 
-$panel-bg:                    $gray-darker;
-$panel-body-padding:          15px;
-$panel-heading-padding:       10px 15px;
-$panel-footer-padding:        $panel-heading-padding;
-$panel-border-radius:         $border-radius-base;
+$panel-bg:                    $gray-darker !default;
+$panel-body-padding:          15px !default;
+$panel-heading-padding:       10px 15px !default;
+$panel-footer-padding:        $panel-heading-padding !default;
+$panel-border-radius:         $border-radius-base !default;
 
 //** Border color for elements within panels
-$panel-inner-border:          $gray-dark;
-$panel-footer-bg:             lighten($gray-darker, 10%);
+$panel-inner-border:          $gray-dark !default;
+$panel-footer-bg:             lighten($gray-darker, 10%) !default;
 
-$panel-default-text:          $text-color;
-$panel-default-border:        $panel-inner-border;
-$panel-default-heading-bg:    $panel-footer-bg;
+$panel-default-text:          $text-color !default;
+$panel-default-border:        $panel-inner-border !default;
+$panel-default-heading-bg:    $panel-footer-bg !default;
 
-$panel-primary-text:          #fff;
-$panel-primary-border:        $brand-primary;
-$panel-primary-heading-bg:    $brand-primary;
+$panel-primary-text:          #fff !default;
+$panel-primary-border:        $brand-primary !default;
+$panel-primary-heading-bg:    $brand-primary !default;
 
-$panel-success-text:          $state-success-text;
-$panel-success-border:        $state-success-border;
-$panel-success-heading-bg:    $state-success-bg;
+$panel-success-text:          $state-success-text !default;
+$panel-success-border:        $state-success-border !default;
+$panel-success-heading-bg:    $state-success-bg !default;
 
-$panel-info-text:             $state-info-text;
-$panel-info-border:           $state-info-border;
-$panel-info-heading-bg:       $state-info-bg;
+$panel-info-text:             $state-info-text !default;
+$panel-info-border:           $state-info-border !default;
+$panel-info-heading-bg:       $state-info-bg !default;
 
-$panel-warning-text:          $state-warning-text;
-$panel-warning-border:        $state-warning-border;
-$panel-warning-heading-bg:    $state-warning-bg;
+$panel-warning-text:          $state-warning-text !default;
+$panel-warning-border:        $state-warning-border !default;
+$panel-warning-heading-bg:    $state-warning-bg !default;
 
-$panel-danger-text:           $state-danger-text;
-$panel-danger-border:         $state-danger-border;
-$panel-danger-heading-bg:     $state-danger-bg;
+$panel-danger-text:           $state-danger-text !default;
+$panel-danger-border:         $state-danger-border !default;
+$panel-danger-heading-bg:     $state-danger-bg !default;
 
 
 //== Thumbnails
@@ -736,103 +736,103 @@ $panel-danger-heading-bg:     $state-danger-bg;
 //##
 
 //** Padding around the thumbnail image
-$thumbnail-padding:           4px;
+$thumbnail-padding:           4px !default;
 //** Thumbnail background color
-$thumbnail-bg:                $gray-dark;
+$thumbnail-bg:                $gray-dark !default;
 //** Thumbnail border color
-$thumbnail-border:            $gray-dark;
+$thumbnail-border:            $gray-dark !default;
 //** Thumbnail border radius
-$thumbnail-border-radius:     $border-radius-base;
+$thumbnail-border-radius:     $border-radius-base !default;
 
 //** Custom text color for thumbnail captions
-$thumbnail-caption-color:     $text-color;
+$thumbnail-caption-color:     $text-color !default;
 //** Padding around the thumbnail caption
-$thumbnail-caption-padding:   9px;
+$thumbnail-caption-padding:   9px !default;
 
 
 //== Wells
 //
 //##
 
-$well-bg:                     darken($gray-darker, 5%);
-$well-border:                 darken($well-bg, 7%);
+$well-bg:                     darken($gray-darker, 5%) !default;
+$well-border:                 darken($well-bg, 7%) !default;
 
 
 //== Badges
 //
 //##
 
-$badge-color:                 #fff;
+$badge-color:                 #fff !default;
 //** Linked badge text color on hover
-$badge-link-hover-color:      #fff;
-$badge-bg:                    $brand-primary;
+$badge-link-hover-color:      #fff !default;
+$badge-bg:                    $brand-primary !default;
 
 //** Badge text color in active nav link
-$badge-active-color:          $brand-primary;
+$badge-active-color:          $brand-primary !default;
 //** Badge background color in active nav link
-$badge-active-bg:             #fff;
+$badge-active-bg:             #fff !default;
 
-$badge-font-weight:           bold;
-$badge-line-height:           1;
-$badge-border-radius:         10px;
+$badge-font-weight:           bold !default;
+$badge-line-height:           1 !default;
+$badge-border-radius:         10px !default;
 
 
 //== Breadcrumbs
 //
 //##
 
-$breadcrumb-padding-vertical:   8px;
-$breadcrumb-padding-horizontal: 15px;
+$breadcrumb-padding-vertical:   8px !default;
+$breadcrumb-padding-horizontal: 15px !default;
 //** Breadcrumb background color
-$breadcrumb-bg:                 $gray-darker;
+$breadcrumb-bg:                 $gray-darker !default;
 //** Breadcrumb text color
-$breadcrumb-color:              #fff;
+$breadcrumb-color:              #fff !default;
 //** Text color of current page in the breadcrumb
-$breadcrumb-active-color:       $text-color;
+$breadcrumb-active-color:       $text-color !default;
 //** Textual separator for between breadcrumb elements
-$breadcrumb-separator:          "/";
+$breadcrumb-separator:          "/" !default;
 
 
 //== Carousel
 //
 //##
 
-$carousel-text-shadow:                        0 1px 2px rgba(0,0,0,.6);
+$carousel-text-shadow:                        0 1px 2px rgba(0,0,0,.6) !default;
 
-$carousel-control-color:                      #fff;
-$carousel-control-width:                      15%;
-$carousel-control-opacity:                    .5;
-$carousel-control-font-size:                  20px;
+$carousel-control-color:                      #fff !default;
+$carousel-control-width:                      15% !default;
+$carousel-control-opacity:                    .5 !default;
+$carousel-control-font-size:                  20px !default;
 
-$carousel-indicator-active-bg:                #fff;
-$carousel-indicator-border-color:             #fff;
+$carousel-indicator-active-bg:                #fff !default;
+$carousel-indicator-border-color:             #fff !default;
 
-$carousel-caption-color:                      #fff;
+$carousel-caption-color:                      #fff !default;
 
 
 //== Close
 //
 //##
 
-$close-font-weight:           bold;
-$close-color:                 #000;
-$close-text-shadow:           0 1px 0 #fff;
+$close-font-weight:           bold !default;
+$close-color:                 #000 !default;
+$close-text-shadow:           0 1px 0 #fff !default;
 
 
 //== Code
 //
 //##
 
-$code-color:                  #c7254e;
-$code-bg:                     #f9f2f4;
+$code-color:                  #c7254e !default;
+$code-bg:                     #f9f2f4 !default;
 
-$kbd-color:                   #fff;
-$kbd-bg:                      #333;
+$kbd-color:                   #fff !default;
+$kbd-bg:                      #333 !default;
 
-$pre-bg:                      #f5f5f5;
-$pre-color:                   $gray-dark;
-$pre-border-color:            #ccc;
-$pre-scrollable-max-height:   340px;
+$pre-bg:                      #f5f5f5 !default;
+$pre-color:                   $gray-dark !default;
+$pre-border-color:            #ccc !default;
+$pre-scrollable-max-height:   340px !default;
 
 
 //== Type
@@ -840,22 +840,22 @@ $pre-scrollable-max-height:   340px;
 //##
 
 //** Horizontal offset for forms and lists.
-$component-offset-horizontal: 180px;
+$component-offset-horizontal: 180px !default;
 //** Text muted color
-$text-muted:                  $gray-light;
+$text-muted:                  $gray-light !default;
 //** Abbreviations and acronyms border color
-$abbr-border-color:           $gray-light;
+$abbr-border-color:           $gray-light !default;
 //** Headings small color
-$headings-small-color:        $gray-light;
+$headings-small-color:        $gray-light !default;
 //** Blockquote small color
-$blockquote-small-color:      $gray;
+$blockquote-small-color:      $gray !default;
 //** Blockquote font size
-$blockquote-font-size:        ($font-size-base * 1.25);
+$blockquote-font-size:        ($font-size-base * 1.25) !default;
 //** Blockquote border color
-$blockquote-border-color:     $gray-dark;
+$blockquote-border-color:     $gray-dark !default;
 //** Page header border color
-$page-header-border-color:    $gray-dark;
+$page-header-border-color:    $gray-dark !default;
 //** Width of horizontal description list titles
-$dl-horizontal-offset:        $component-offset-horizontal;
+$dl-horizontal-offset:        $component-offset-horizontal !default;
 //** Horizontal line color.
-$hr-border:                   $gray-dark;
+$hr-border:                   $gray-dark !default;
diff --git a/darkly/_variables.scss b/darkly/_variables.scss
index 62280d6f..413a59f8 100644
--- a/darkly/_variables.scss
+++ b/darkly/_variables.scss
@@ -7,18 +7,18 @@
 //
 //## Gray and brand colors for use across Bootstrap.
 
-$gray-base:              #000;
-$gray-darker:            lighten($gray-base, 13.5%); // #222
-$gray-dark:              #303030;   // #333
-$gray:                   #464545;
-$gray-light:             #999;   // #999
-$gray-lighter:           #EBEBEB; // #eee
+$gray-base:              #000 !default;
+$gray-darker:            lighten($gray-base, 13.5%) !default; // #222
+$gray-dark:              #303030 !default;   // #333
+$gray:                   #464545 !default;
+$gray-light:             #999 !default;   // #999
+$gray-lighter:           #EBEBEB !default; // #eee
 
-$brand-primary:         #375a7f;
-$brand-success:         #00bc8c;
-$brand-info:            #3498DB;
-$brand-warning:         #F39C12;
-$brand-danger:          #E74C3C;
+$brand-primary:         #375a7f !default;
+$brand-success:         #00bc8c !default;
+$brand-info:            #3498DB !default;
+$brand-warning:         #F39C12 !default;
+$brand-danger:          #E74C3C !default;
 
 
 //== Scaffolding
@@ -26,49 +26,49 @@ $brand-danger:          #E74C3C;
 //## Settings for some of the most global styles.
 
 //** Background color for ``.
-$body-bg:               $gray-darker;
+$body-bg:               $gray-darker !default;
 //** Global text color on ``.
-$text-color:            #fff;
+$text-color:            #fff !default;
 
 //** Global textual link color.
-$link-color:            desaturate(lighten($brand-success, 10%),10%);
+$link-color:            desaturate(lighten($brand-success, 10%),10%) !default;
 //** Link hover color set via `darken()` function.
-$link-hover-color:      $link-color;
+$link-hover-color:      $link-color !default;
 //** Link hover decoration.
-$link-hover-decoration: underline;
+$link-hover-decoration: underline !default;
 
 
 //== Typography
 //
 //## Font, line-height, and color for body text, headings, and more.
 
-$font-family-sans-serif:  "Lato", "Helvetica Neue", Helvetica, Arial, sans-serif;
-$font-family-serif:       Georgia, "Times New Roman", Times, serif;
+$font-family-sans-serif:  "Lato", "Helvetica Neue", Helvetica, Arial, sans-serif !default;
+$font-family-serif:       Georgia, "Times New Roman", Times, serif !default;
 //** Default monospace fonts for ``, ``, and `
`.
-$font-family-monospace:   Menlo, Monaco, Consolas, "Courier New", monospace;
-$font-family-base:        $font-family-sans-serif;
+$font-family-monospace:   Menlo, Monaco, Consolas, "Courier New", monospace !default;
+$font-family-base:        $font-family-sans-serif !default;
 
-$font-size-base:          15px;
-$font-size-large:         ceil(($font-size-base * 1.25)); // ~18px
-$font-size-small:         ceil(($font-size-base * 0.85)); // ~12px
+$font-size-base:          15px !default;
+$font-size-large:         ceil(($font-size-base * 1.25)) !default; // ~18px
+$font-size-small:         ceil(($font-size-base * 0.85)) !default; // ~12px
 
-$font-size-h1:            floor(($font-size-base * 2.6)); // ~36px
-$font-size-h2:            floor(($font-size-base * 2.15)); // ~30px
-$font-size-h3:            ceil(($font-size-base * 1.7)); // ~24px
-$font-size-h4:            ceil(($font-size-base * 1.25)); // ~18px
-$font-size-h5:            $font-size-base;
-$font-size-h6:            ceil(($font-size-base * 0.85)); // ~12px
+$font-size-h1:            floor(($font-size-base * 2.6)) !default; // ~36px
+$font-size-h2:            floor(($font-size-base * 2.15)) !default; // ~30px
+$font-size-h3:            ceil(($font-size-base * 1.7)) !default; // ~24px
+$font-size-h4:            ceil(($font-size-base * 1.25)) !default; // ~18px
+$font-size-h5:            $font-size-base !default;
+$font-size-h6:            ceil(($font-size-base * 0.85)) !default; // ~12px
 
 //** Unit-less `line-height` for use in components like buttons.
-$line-height-base:        1.428571429; // 20/14
+$line-height-base:        1.428571429 !default; // 20/14
 //** Computed "line-height" (`font-size` * `line-height`) for use with `margin`, `padding`, etc.
-$line-height-computed:    floor(($font-size-base * $line-height-base)); // ~20px
+$line-height-computed:    floor(($font-size-base * $line-height-base)) !default; // ~20px
 
 //** By default, this inherits from the ``.
-$headings-font-family:    $font-family-base;
-$headings-font-weight:    400;
-$headings-line-height:    1.1;
-$headings-color:          inherit;
+$headings-font-family:    $font-family-base !default;
+$headings-font-weight:    400 !default;
+$headings-line-height:    1.1 !default;
+$headings-color:          inherit !default;
 
 
 //== Iconography
@@ -76,45 +76,45 @@ $headings-color:          inherit;
 //## Specify custom location and filename of the included Glyphicons icon font. Useful for those including Bootstrap via Bower.
 
 //** Load fonts from this directory.
-$icon-font-path:          "../fonts/";
+$icon-font-path:          "../fonts/" !default;
 //** File name for all font files.
-$icon-font-name:          "glyphicons-halflings-regular";
+$icon-font-name:          "glyphicons-halflings-regular" !default;
 //** Element ID within SVG icon file.
-$icon-font-svg-id:        "glyphicons_halflingsregular";
+$icon-font-svg-id:        "glyphicons_halflingsregular" !default;
 
 
 //== Components
 //
 //## Define common padding and border radius sizes and more. Values based on 14px text and 1.428 line-height (~20px to start).
 
-$padding-base-vertical:     10px;
-$padding-base-horizontal:   15px;
+$padding-base-vertical:     10px !default;
+$padding-base-horizontal:   15px !default;
 
-$padding-large-vertical:    18px;
-$padding-large-horizontal:  27px;
+$padding-large-vertical:    18px !default;
+$padding-large-horizontal:  27px !default;
 
-$padding-small-vertical:    6px;
-$padding-small-horizontal:  9px;
+$padding-small-vertical:    6px !default;
+$padding-small-horizontal:  9px !default;
 
-$padding-xs-vertical:       1px;
-$padding-xs-horizontal:     5px;
+$padding-xs-vertical:       1px !default;
+$padding-xs-horizontal:     5px !default;
 
-$line-height-large:         1.3333333; // extra decimals for Win 8.1 Chrome
-$line-height-small:         1.5;
+$line-height-large:         1.3333333 !default; // extra decimals for Win 8.1 Chrome
+$line-height-small:         1.5 !default;
 
-$border-radius-base:        4px;
-$border-radius-large:       6px;
-$border-radius-small:       3px;
+$border-radius-base:        4px !default;
+$border-radius-large:       6px !default;
+$border-radius-small:       3px !default;
 
 //** Global color for active items (e.g., navs or dropdowns).
-$component-active-color:    #fff;
+$component-active-color:    #fff !default;
 //** Global background color for active items (e.g., navs or dropdowns).
-$component-active-bg:       $brand-primary;
+$component-active-bg:       $brand-primary !default;
 
 //** Width of the `border` for generating carets that indicator dropdowns.
-$caret-width-base:          4px;
+$caret-width-base:          4px !default;
 //** Carets increase slightly in size for larger components.
-$caret-width-large:         5px;
+$caret-width-large:         5px !default;
 
 
 //== Tables
@@ -122,53 +122,53 @@ $caret-width-large:         5px;
 //## Customizes the `.table` component with basic values, each used across all table variations.
 
 //** Padding for ``s and ``s.
-$table-cell-padding:            8px;
+$table-cell-padding:            8px !default;
 //** Padding for cells in `.table-condensed`.
-$table-condensed-cell-padding:  5px;
+$table-condensed-cell-padding:  5px !default;
 
 //** Default background color used for all tables.
-$table-bg:                      transparent;
+$table-bg:                      transparent !default;
 //** Background color used for `.table-striped`.
-$table-bg-accent:               lighten($gray-dark, 5%);
+$table-bg-accent:               lighten($gray-dark, 5%) !default;
 //** Background color used for `.table-hover`.
-$table-bg-hover:                $gray;
-$table-bg-active:               $table-bg-hover;
+$table-bg-hover:                $gray !default;
+$table-bg-active:               $table-bg-hover !default;
 
 //** Border color for table and cell borders.
-$table-border-color:            $gray;
+$table-border-color:            $gray !default;
 
 
 //== Buttons
 //
 //## For each of Bootstrap's buttons, define text, background and border color.
 
-$btn-font-weight:                normal;
+$btn-font-weight:                normal !default;
 
-$btn-default-color:              $text-color;
-$btn-default-bg:                 $gray;
-$btn-default-border:             $btn-default-bg;
+$btn-default-color:              $text-color !default;
+$btn-default-bg:                 $gray !default;
+$btn-default-border:             $btn-default-bg !default;
 
-$btn-primary-color:              #fff;
-$btn-primary-bg:                 $brand-primary;
-$btn-primary-border:             $btn-primary-bg;
+$btn-primary-color:              #fff !default;
+$btn-primary-bg:                 $brand-primary !default;
+$btn-primary-border:             $btn-primary-bg !default;
 
-$btn-success-color:              $btn-primary-color;
-$btn-success-bg:                 $brand-success;
-$btn-success-border:             $btn-success-bg;
+$btn-success-color:              $btn-primary-color !default;
+$btn-success-bg:                 $brand-success !default;
+$btn-success-border:             $btn-success-bg !default;
 
-$btn-info-color:                 $btn-success-color;
-$btn-info-bg:                    $brand-info;
-$btn-info-border:                $btn-info-bg;
+$btn-info-color:                 $btn-success-color !default;
+$btn-info-bg:                    $brand-info !default;
+$btn-info-border:                $btn-info-bg !default;
 
-$btn-warning-color:              $btn-success-color;
-$btn-warning-bg:                 $brand-warning;
-$btn-warning-border:             $btn-warning-bg;
+$btn-warning-color:              $btn-success-color !default;
+$btn-warning-bg:                 $brand-warning !default;
+$btn-warning-border:             $btn-warning-bg !default;
 
-$btn-danger-color:               $btn-success-color;
-$btn-danger-bg:                  $brand-danger;
-$btn-danger-border:              $btn-danger-bg;
+$btn-danger-color:               $btn-success-color !default;
+$btn-danger-bg:                  $brand-danger !default;
+$btn-danger-border:              $btn-danger-bg !default;
 
-$btn-link-disabled-color:        $gray-light;
+$btn-link-disabled-color:        $gray-light !default;
 
 
 //== Forms
@@ -176,50 +176,50 @@ $btn-link-disabled-color:        $gray-light;
 //##
 
 //** `` background color
-$input-bg:                       #fff;
+$input-bg:                       #fff !default;
 //** `` background color
-$input-bg-disabled:              $gray-lighter;
+$input-bg-disabled:              $gray-lighter !default;
 
 //** Text color for ``s
-$input-color:                    $gray;
+$input-color:                    $gray !default;
 //** `` border color
-$input-border:                   #f1f1f1;
+$input-border:                   #f1f1f1 !default;
 
 // TODO: Rename `$input-border-radius` to `$input-border-radius-base` in v4
 //** Default `.form-control` border radius
 // This has no effect on ``s in CSS.
-$input-border-radius:            $border-radius-base;
+$input-border-radius:            $border-radius-base !default;
 //** Large `.form-control` border radius
-$input-border-radius-large:      $border-radius-large;
+$input-border-radius-large:      $border-radius-large !default;
 //** Small `.form-control` border radius
-$input-border-radius-small:      $border-radius-small;
+$input-border-radius-small:      $border-radius-small !default;
 
 //** Border color for inputs on focus
-$input-border-focus:             #fff;
+$input-border-focus:             #fff !default;
 
 //** Placeholder text color
-$input-color-placeholder:        $gray-light;
+$input-color-placeholder:        $gray-light !default;
 
 //** Default `.form-control` height
-$input-height-base:              ($line-height-computed + ($padding-base-vertical * 2) + 4);
+$input-height-base:              ($line-height-computed + ($padding-base-vertical * 2) + 4) !default;
 //** Large `.form-control` height
-$input-height-large:             (ceil($font-size-large * $line-height-large) + ($padding-large-vertical * 2) + 4);
+$input-height-large:             (ceil($font-size-large * $line-height-large) + ($padding-large-vertical * 2) + 4) !default;
 //** Small `.form-control` height
-$input-height-small:             (floor($font-size-small * $line-height-small) + ($padding-small-vertical * 2) + 4);
+$input-height-small:             (floor($font-size-small * $line-height-small) + ($padding-small-vertical * 2) + 4) !default;
 
 //** `.form-group` margin
-$form-group-margin-bottom:       15px;
+$form-group-margin-bottom:       15px !default;
 
-$legend-color:                   $text-color;
-$legend-border-color:            transparent;
+$legend-color:                   $text-color !default;
+$legend-border-color:            transparent !default;
 
 //** Background color for textual input addons
-$input-group-addon-bg:           $gray;
+$input-group-addon-bg:           $gray !default;
 //** Border color for textual input addons
-$input-group-addon-border-color: transparent;
+$input-group-addon-border-color: transparent !default;
 
 //** Disabled cursor for form controls and buttons.
-$cursor-disabled:                not-allowed;
+$cursor-disabled:                not-allowed !default;
 
 
 //== Dropdowns
@@ -227,34 +227,34 @@ $cursor-disabled:                not-allowed;
 //## Dropdown menu container and contents.
 
 //** Background for the dropdown menu.
-$dropdown-bg:                    $gray-dark;
+$dropdown-bg:                    $gray-dark !default;
 //** Dropdown menu `border-color`.
-$dropdown-border:                rgba(0,0,0,.15);
+$dropdown-border:                rgba(0,0,0,.15) !default;
 //** Dropdown menu `border-color` **for IE8**.
-$dropdown-fallback-border:       #ccc;
+$dropdown-fallback-border:       #ccc !default;
 //** Divider color for between dropdown items.
-$dropdown-divider-bg:            $gray;
+$dropdown-divider-bg:            $gray !default;
 
 //** Dropdown link text color.
-$dropdown-link-color:            $gray-lighter;
+$dropdown-link-color:            $gray-lighter !default;
 //** Hover color for dropdown links.
-$dropdown-link-hover-color:      #fff;
+$dropdown-link-hover-color:      #fff !default;
 //** Hover background for dropdown links.
-$dropdown-link-hover-bg:         $component-active-bg;
+$dropdown-link-hover-bg:         $component-active-bg !default;
 
 //** Active dropdown menu item text color.
-$dropdown-link-active-color:     #fff;
+$dropdown-link-active-color:     #fff !default;
 //** Active dropdown menu item background color.
-$dropdown-link-active-bg:        $component-active-bg;
+$dropdown-link-active-bg:        $component-active-bg !default;
 
 //** Disabled dropdown menu item background color.
-$dropdown-link-disabled-color:   $gray-light;
+$dropdown-link-disabled-color:   $gray-light !default;
 
 //** Text color for headers within dropdown menus.
-$dropdown-header-color:          $gray-light;
+$dropdown-header-color:          $gray-light !default;
 
 //** Deprecated `$dropdown-caret-color` as of v3.1.0
-$dropdown-caret-color:           #000;
+$dropdown-caret-color:           #000 !default;
 
 
 //-- Z-index master list
@@ -264,13 +264,13 @@ $dropdown-caret-color:           #000;
 //
 // Note: These variables are not generated into the Customizer.
 
-$zindex-navbar:            1000;
-$zindex-dropdown:          1000;
-$zindex-popover:           1060;
-$zindex-tooltip:           1070;
-$zindex-navbar-fixed:      1030;
-$zindex-modal-background:  1040;
-$zindex-modal:             1050;
+$zindex-navbar:            1000 !default;
+$zindex-dropdown:          1000 !default;
+$zindex-popover:           1060 !default;
+$zindex-tooltip:           1070 !default;
+$zindex-navbar-fixed:      1030 !default;
+$zindex-modal-background:  1040 !default;
+$zindex-modal:             1050 !default;
 
 
 //== Media queries breakpoints
@@ -279,37 +279,37 @@ $zindex-modal:             1050;
 
 // Extra small screen / phone
 //** Deprecated `$screen-xs` as of v3.0.1
-$screen-xs:                  480px;
+$screen-xs:                  480px !default;
 //** Deprecated `$screen-xs-min` as of v3.2.0
-$screen-xs-min:              $screen-xs;
+$screen-xs-min:              $screen-xs !default;
 //** Deprecated `$screen-phone` as of v3.0.1
-$screen-phone:               $screen-xs-min;
+$screen-phone:               $screen-xs-min !default;
 
 // Small screen / tablet
 //** Deprecated `$screen-sm` as of v3.0.1
-$screen-sm:                  768px;
-$screen-sm-min:              $screen-sm;
+$screen-sm:                  768px !default;
+$screen-sm-min:              $screen-sm !default;
 //** Deprecated `$screen-tablet` as of v3.0.1
-$screen-tablet:              $screen-sm-min;
+$screen-tablet:              $screen-sm-min !default;
 
 // Medium screen / desktop
 //** Deprecated `$screen-md` as of v3.0.1
-$screen-md:                  992px;
-$screen-md-min:              $screen-md;
+$screen-md:                  992px !default;
+$screen-md-min:              $screen-md !default;
 //** Deprecated `$screen-desktop` as of v3.0.1
-$screen-desktop:             $screen-md-min;
+$screen-desktop:             $screen-md-min !default;
 
 // Large screen / wide desktop
 //** Deprecated `$screen-lg` as of v3.0.1
-$screen-lg:                  1200px;
-$screen-lg-min:              $screen-lg;
+$screen-lg:                  1200px !default;
+$screen-lg-min:              $screen-lg !default;
 //** Deprecated `$screen-lg-desktop` as of v3.0.1
-$screen-lg-desktop:          $screen-lg-min;
+$screen-lg-desktop:          $screen-lg-min !default;
 
 // So media queries don't overlap when required, provide a maximum
-$screen-xs-max:              ($screen-sm-min - 1);
-$screen-sm-max:              ($screen-md-min - 1);
-$screen-md-max:              ($screen-lg-min - 1);
+$screen-xs-max:              ($screen-sm-min - 1) !default;
+$screen-sm-max:              ($screen-md-min - 1) !default;
+$screen-md-max:              ($screen-lg-min - 1) !default;
 
 
 //== Grid system
@@ -317,14 +317,14 @@ $screen-md-max:              ($screen-lg-min - 1);
 //## Define your custom responsive grid.
 
 //** Number of columns in the grid.
-$grid-columns:              12;
+$grid-columns:              12 !default;
 //** Padding between columns. Gets divided in half for the left and right.
-$grid-gutter-width:         30px;
+$grid-gutter-width:         30px !default;
 // Navbar collapse
 //** Point at which the navbar becomes uncollapsed.
-$grid-float-breakpoint:     $screen-sm-min;
+$grid-float-breakpoint:     $screen-sm-min !default;
 //** Point at which the navbar begins collapsing.
-$grid-float-breakpoint-max: ($grid-float-breakpoint - 1);
+$grid-float-breakpoint-max: ($grid-float-breakpoint - 1) !default;
 
 
 //== Container sizes
@@ -332,19 +332,19 @@ $grid-float-breakpoint-max: ($grid-float-breakpoint - 1);
 //## Define the maximum width of `.container` for different screen sizes.
 
 // Small screen / tablet
-$container-tablet:             (720px + $grid-gutter-width);
+$container-tablet:             (720px + $grid-gutter-width) !default;
 //** For `$screen-sm-min` and up.
-$container-sm:                 $container-tablet;
+$container-sm:                 $container-tablet !default;
 
 // Medium screen / desktop
-$container-desktop:            (940px + $grid-gutter-width);
+$container-desktop:            (940px + $grid-gutter-width) !default;
 //** For `$screen-md-min` and up.
-$container-md:                 $container-desktop;
+$container-md:                 $container-desktop !default;
 
 // Large screen / wide desktop
-$container-large-desktop:      (1140px + $grid-gutter-width);
+$container-large-desktop:      (1140px + $grid-gutter-width) !default;
 //** For `$screen-lg-min` and up.
-$container-lg:                 $container-large-desktop;
+$container-lg:                 $container-large-desktop !default;
 
 
 //== Navbar
@@ -352,61 +352,61 @@ $container-lg:                 $container-large-desktop;
 //##
 
 // Basics of a navbar
-$navbar-height:                    60px;
-$navbar-margin-bottom:             $line-height-computed;
-$navbar-border-radius:             $border-radius-base;
-$navbar-padding-horizontal:        floor(($grid-gutter-width / 2));
-$navbar-padding-vertical:          (($navbar-height - $line-height-computed) / 2);
-$navbar-collapse-max-height:       340px;
+$navbar-height:                    60px !default;
+$navbar-margin-bottom:             $line-height-computed !default;
+$navbar-border-radius:             $border-radius-base !default;
+$navbar-padding-horizontal:        floor(($grid-gutter-width / 2)) !default;
+$navbar-padding-vertical:          (($navbar-height - $line-height-computed) / 2) !default;
+$navbar-collapse-max-height:       340px !default;
 
-$navbar-default-color:             #777;
-$navbar-default-bg:                $brand-primary;
-$navbar-default-border:            transparent;
+$navbar-default-color:             #777 !default;
+$navbar-default-bg:                $brand-primary !default;
+$navbar-default-border:            transparent !default;
 
 // Navbar links
-$navbar-default-link-color:                #fff;
-$navbar-default-link-hover-color:          $brand-success;
-$navbar-default-link-hover-bg:             transparent;
-$navbar-default-link-active-color:         #fff;
-$navbar-default-link-active-bg:            darken($navbar-default-bg, 10%);
-$navbar-default-link-disabled-color:       #ccc;
-$navbar-default-link-disabled-bg:          transparent;
+$navbar-default-link-color:                #fff !default;
+$navbar-default-link-hover-color:          $brand-success !default;
+$navbar-default-link-hover-bg:             transparent !default;
+$navbar-default-link-active-color:         #fff !default;
+$navbar-default-link-active-bg:            darken($navbar-default-bg, 10%) !default;
+$navbar-default-link-disabled-color:       #ccc !default;
+$navbar-default-link-disabled-bg:          transparent !default;
 
 // Navbar brand label
-$navbar-default-brand-color:               $navbar-default-link-color;
-$navbar-default-brand-hover-color:         $navbar-default-link-hover-color;
-$navbar-default-brand-hover-bg:            transparent;
+$navbar-default-brand-color:               $navbar-default-link-color !default;
+$navbar-default-brand-hover-color:         $navbar-default-link-hover-color !default;
+$navbar-default-brand-hover-bg:            transparent !default;
 
 // Navbar toggle
-$navbar-default-toggle-hover-bg:           darken($navbar-default-bg, 10%);
-$navbar-default-toggle-icon-bar-bg:        #fff;
-$navbar-default-toggle-border-color:       darken($navbar-default-bg, 10%);
+$navbar-default-toggle-hover-bg:           darken($navbar-default-bg, 10%) !default;
+$navbar-default-toggle-icon-bar-bg:        #fff !default;
+$navbar-default-toggle-border-color:       darken($navbar-default-bg, 10%) !default;
 
 
 // Inverted navbar
 // Reset inverted navbar basics
-$navbar-inverse-color:                      #fff;
-$navbar-inverse-bg:                         $brand-success;
-$navbar-inverse-border:                     transparent;
+$navbar-inverse-color:                      #fff !default;
+$navbar-inverse-bg:                         $brand-success !default;
+$navbar-inverse-border:                     transparent !default;
 
 // Inverted navbar links
-$navbar-inverse-link-color:                 $navbar-inverse-color;
-$navbar-inverse-link-hover-color:           $brand-primary;
-$navbar-inverse-link-hover-bg:              transparent;
-$navbar-inverse-link-active-color:          $navbar-inverse-color;
-$navbar-inverse-link-active-bg:             darken($navbar-inverse-bg, 5%);
-$navbar-inverse-link-disabled-color:        #aaa;
-$navbar-inverse-link-disabled-bg:           transparent;
+$navbar-inverse-link-color:                 $navbar-inverse-color !default;
+$navbar-inverse-link-hover-color:           $brand-primary !default;
+$navbar-inverse-link-hover-bg:              transparent !default;
+$navbar-inverse-link-active-color:          $navbar-inverse-color !default;
+$navbar-inverse-link-active-bg:             darken($navbar-inverse-bg, 5%) !default;
+$navbar-inverse-link-disabled-color:        #aaa !default;
+$navbar-inverse-link-disabled-bg:           transparent !default;
 
 // Inverted navbar brand label
-$navbar-inverse-brand-color:                $navbar-inverse-link-color;
-$navbar-inverse-brand-hover-color:          $navbar-inverse-link-hover-color;
-$navbar-inverse-brand-hover-bg:             transparent;
+$navbar-inverse-brand-color:                $navbar-inverse-link-color !default;
+$navbar-inverse-brand-hover-color:          $navbar-inverse-link-hover-color !default;
+$navbar-inverse-brand-hover-bg:             transparent !default;
 
 // Inverted navbar toggle
-$navbar-inverse-toggle-hover-bg:            darken($navbar-inverse-bg, 10%);
-$navbar-inverse-toggle-icon-bar-bg:         #fff;
-$navbar-inverse-toggle-border-color:        darken($navbar-inverse-bg, 10%);
+$navbar-inverse-toggle-hover-bg:            darken($navbar-inverse-bg, 10%) !default;
+$navbar-inverse-toggle-icon-bar-bg:         #fff !default;
+$navbar-inverse-toggle-border-color:        darken($navbar-inverse-bg, 10%) !default;
 
 
 //== Navs
@@ -414,97 +414,97 @@ $navbar-inverse-toggle-border-color:        darken($navbar-inverse-bg, 10%);
 //##
 
 //=== Shared nav styles
-$nav-link-padding:                          10px 15px;
-$nav-link-hover-bg:                         $gray-dark;
+$nav-link-padding:                          10px 15px !default;
+$nav-link-hover-bg:                         $gray-dark !default;
 
-$nav-disabled-link-color:                   lighten($gray, 10%);
-$nav-disabled-link-hover-color:             lighten($gray, 10%);
+$nav-disabled-link-color:                   lighten($gray, 10%) !default;
+$nav-disabled-link-hover-color:             lighten($gray, 10%) !default;
 
 //== Tabs
-$nav-tabs-border-color:                     $gray;
+$nav-tabs-border-color:                     $gray !default;
 
-$nav-tabs-link-hover-border-color:          $gray;
+$nav-tabs-link-hover-border-color:          $gray !default;
 
-$nav-tabs-active-link-hover-bg:             $body-bg;
-$nav-tabs-active-link-hover-color:          $brand-success;
-$nav-tabs-active-link-hover-border-color:   $nav-tabs-link-hover-border-color;
+$nav-tabs-active-link-hover-bg:             $body-bg !default;
+$nav-tabs-active-link-hover-color:          $brand-success !default;
+$nav-tabs-active-link-hover-border-color:   $nav-tabs-link-hover-border-color !default;
 
-$nav-tabs-justified-link-border-color:            $gray-lighter;
-$nav-tabs-justified-active-link-border-color:     $body-bg;
+$nav-tabs-justified-link-border-color:            $gray-lighter !default;
+$nav-tabs-justified-active-link-border-color:     $body-bg !default;
 
 //== Pills
-$nav-pills-border-radius:                   $border-radius-base;
-$nav-pills-active-link-hover-bg:            $component-active-bg;
-$nav-pills-active-link-hover-color:         $component-active-color;
+$nav-pills-border-radius:                   $border-radius-base !default;
+$nav-pills-active-link-hover-bg:            $component-active-bg !default;
+$nav-pills-active-link-hover-color:         $component-active-color !default;
 
 
 //== Pagination
 //
 //##
 
-$pagination-color:                     #fff;
-$pagination-bg:                        $brand-success;
-$pagination-border:                    transparent;
+$pagination-color:                     #fff !default;
+$pagination-bg:                        $brand-success !default;
+$pagination-border:                    transparent !default;
 
-$pagination-hover-color:               #fff;
-$pagination-hover-bg:                  lighten($brand-success, 6%);
-$pagination-hover-border:              transparent;
+$pagination-hover-color:               #fff !default;
+$pagination-hover-bg:                  lighten($brand-success, 6%) !default;
+$pagination-hover-border:              transparent !default;
 
-$pagination-active-color:              #fff;
-$pagination-active-bg:                 lighten($brand-success, 6%);
-$pagination-active-border:             transparent;
+$pagination-active-color:              #fff !default;
+$pagination-active-bg:                 lighten($brand-success, 6%) !default;
+$pagination-active-border:             transparent !default;
 
-$pagination-disabled-color:            #fff;
-$pagination-disabled-bg:               darken($brand-success, 15%);
-$pagination-disabled-border:           transparent;
+$pagination-disabled-color:            #fff !default;
+$pagination-disabled-bg:               darken($brand-success, 15%) !default;
+$pagination-disabled-border:           transparent !default;
 
 
 //== Pager
 //
 //##
 
-$pager-bg:                             $pagination-bg;
-$pager-border:                         $pagination-border;
-$pager-border-radius:                  15px;
+$pager-bg:                             $pagination-bg !default;
+$pager-border:                         $pagination-border !default;
+$pager-border-radius:                  15px !default;
 
-$pager-hover-bg:                       $pagination-hover-bg;
+$pager-hover-bg:                       $pagination-hover-bg !default;
 
-$pager-active-bg:                      $pagination-active-bg;
-$pager-active-color:                   $pagination-active-color;
+$pager-active-bg:                      $pagination-active-bg !default;
+$pager-active-color:                   $pagination-active-color !default;
 
-$pager-disabled-color:                 #ddd;
+$pager-disabled-color:                 #ddd !default;
 
 
 //== Jumbotron
 //
 //##
 
-$jumbotron-padding:              30px;
-$jumbotron-color:                inherit;
-$jumbotron-bg:                   $gray-dark;
-$jumbotron-heading-color:        inherit;
-$jumbotron-font-size:            ceil(($font-size-base * 1.5));
+$jumbotron-padding:              30px !default;
+$jumbotron-color:                inherit !default;
+$jumbotron-bg:                   $gray-dark !default;
+$jumbotron-heading-color:        inherit !default;
+$jumbotron-font-size:            ceil(($font-size-base * 1.5)) !default;
 
 
 //== Form states and alerts
 //
 //## Define colors for form feedback states and, by default, alerts.
 
-$state-success-text:             #fff;
-$state-success-bg:               $brand-success;
-$state-success-border:           $brand-success;
+$state-success-text:             #fff !default;
+$state-success-bg:               $brand-success !default;
+$state-success-border:           $brand-success !default;
 
-$state-info-text:                #fff;
-$state-info-bg:                  $brand-info;
-$state-info-border:              $brand-info;
+$state-info-text:                #fff !default;
+$state-info-bg:                  $brand-info !default;
+$state-info-border:              $brand-info !default;
 
-$state-warning-text:             #fff;
-$state-warning-bg:               $brand-warning;
-$state-warning-border:           $brand-warning;
+$state-warning-text:             #fff !default;
+$state-warning-bg:               $brand-warning !default;
+$state-warning-border:           $brand-warning !default;
 
-$state-danger-text:              #fff;
-$state-danger-bg:                $brand-danger;
-$state-danger-border:            $brand-danger;
+$state-danger-text:              #fff !default;
+$state-danger-bg:                $brand-danger !default;
+$state-danger-border:            $brand-danger !default;
 
 
 //== Tooltips
@@ -512,17 +512,17 @@ $state-danger-border:            $brand-danger;
 //##
 
 //** Tooltip max width
-$tooltip-max-width:           200px;
+$tooltip-max-width:           200px !default;
 //** Tooltip text color
-$tooltip-color:               #fff;
+$tooltip-color:               #fff !default;
 //** Tooltip background color
-$tooltip-bg:                  #000;
-$tooltip-opacity:             .9;
+$tooltip-bg:                  #000 !default;
+$tooltip-opacity:             .9 !default;
 
 //** Tooltip arrow width
-$tooltip-arrow-width:         5px;
+$tooltip-arrow-width:         5px !default;
 //** Tooltip arrow color
-$tooltip-arrow-color:         $tooltip-bg;
+$tooltip-arrow-color:         $tooltip-bg !default;
 
 
 //== Popovers
@@ -530,28 +530,28 @@ $tooltip-arrow-color:         $tooltip-bg;
 //##
 
 //** Popover body background color
-$popover-bg:                          $gray-dark;
+$popover-bg:                          $gray-dark !default;
 //** Popover maximum width
-$popover-max-width:                   276px;
+$popover-max-width:                   276px !default;
 //** Popover border color
-$popover-border-color:                rgba(0,0,0,.2);
+$popover-border-color:                rgba(0,0,0,.2) !default;
 //** Popover fallback border color
-$popover-fallback-border-color:       #999;
+$popover-fallback-border-color:       #999 !default;
 
 //** Popover title background color
-$popover-title-bg:                    darken($popover-bg, 3%);
+$popover-title-bg:                    darken($popover-bg, 3%) !default;
 
 //** Popover arrow width
-$popover-arrow-width:                 10px;
+$popover-arrow-width:                 10px !default;
 //** Popover arrow color
-$popover-arrow-color:                 $popover-bg;
+$popover-arrow-color:                 $popover-bg !default;
 
 //** Popover outer arrow width
-$popover-arrow-outer-width:           ($popover-arrow-width + 1);
+$popover-arrow-outer-width:           ($popover-arrow-width + 1) !default;
 //** Popover outer arrow color
-$popover-arrow-outer-color:           fadein($popover-border-color, 5%);
+$popover-arrow-outer-color:           fadein($popover-border-color, 5%) !default;
 //** Popover outer arrow fallback color
-$popover-arrow-outer-fallback-color:  darken($popover-fallback-border-color, 20%);
+$popover-arrow-outer-fallback-color:  darken($popover-fallback-border-color, 20%) !default;
 
 
 //== Labels
@@ -559,22 +559,22 @@ $popover-arrow-outer-fallback-color:  darken($popover-fallback-border-color, 20%
 //##
 
 //** Default label background color
-$label-default-bg:            $gray;
+$label-default-bg:            $gray !default;
 //** Primary label background color
-$label-primary-bg:            $brand-primary;
+$label-primary-bg:            $brand-primary !default;
 //** Success label background color
-$label-success-bg:            $brand-success;
+$label-success-bg:            $brand-success !default;
 //** Info label background color
-$label-info-bg:               $brand-info;
+$label-info-bg:               $brand-info !default;
 //** Warning label background color
-$label-warning-bg:            $brand-warning;
+$label-warning-bg:            $brand-warning !default;
 //** Danger label background color
-$label-danger-bg:             $brand-danger;
+$label-danger-bg:             $brand-danger !default;
 
 //** Default label text color
-$label-color:                 #fff;
+$label-color:                 #fff !default;
 //** Default text color of a linked label
-$label-link-hover-color:      #fff;
+$label-link-hover-color:      #fff !default;
 
 
 //== Modals
@@ -582,57 +582,57 @@ $label-link-hover-color:      #fff;
 //##
 
 //** Padding applied to the modal body
-$modal-inner-padding:         20px;
+$modal-inner-padding:         20px !default;
 
 //** Padding applied to the modal title
-$modal-title-padding:         15px;
+$modal-title-padding:         15px !default;
 //** Modal title line-height
-$modal-title-line-height:     $line-height-base;
+$modal-title-line-height:     $line-height-base !default;
 
 //** Background color of modal content area
-$modal-content-bg:                             $gray-dark;
+$modal-content-bg:                             $gray-dark !default;
 //** Modal content border color
-$modal-content-border-color:                   rgba(0,0,0,.2);
+$modal-content-border-color:                   rgba(0,0,0,.2) !default;
 //** Modal content border color **for IE8**
-$modal-content-fallback-border-color:          #999;
+$modal-content-fallback-border-color:          #999 !default;
 
 //** Modal backdrop background color
-$modal-backdrop-bg:           #000;
+$modal-backdrop-bg:           #000 !default;
 //** Modal backdrop opacity
-$modal-backdrop-opacity:      .7;
+$modal-backdrop-opacity:      .7 !default;
 //** Modal header border color
-$modal-header-border-color:   $gray;
+$modal-header-border-color:   $gray !default;
 //** Modal footer border color
-$modal-footer-border-color:   $modal-header-border-color;
+$modal-footer-border-color:   $modal-header-border-color !default;
 
-$modal-lg:                    900px;
-$modal-md:                    600px;
-$modal-sm:                    300px;
+$modal-lg:                    900px !default;
+$modal-md:                    600px !default;
+$modal-sm:                    300px !default;
 
 
 //== Alerts
 //
 //## Define alert colors, border radius, and padding.
 
-$alert-padding:               15px;
-$alert-border-radius:         $border-radius-base;
-$alert-link-font-weight:      bold;
+$alert-padding:               15px !default;
+$alert-border-radius:         $border-radius-base !default;
+$alert-link-font-weight:      bold !default;
 
-$alert-success-bg:            $state-success-bg;
-$alert-success-text:          $state-success-text;
-$alert-success-border:        $state-success-border;
+$alert-success-bg:            $state-success-bg !default;
+$alert-success-text:          $state-success-text !default;
+$alert-success-border:        $state-success-border !default;
 
-$alert-info-bg:               $state-info-bg;
-$alert-info-text:             $state-info-text;
-$alert-info-border:           $state-info-border;
+$alert-info-bg:               $state-info-bg !default;
+$alert-info-text:             $state-info-text !default;
+$alert-info-border:           $state-info-border !default;
 
-$alert-warning-bg:            $state-warning-bg;
-$alert-warning-text:          $state-warning-text;
-$alert-warning-border:        $state-warning-border;
+$alert-warning-bg:            $state-warning-bg !default;
+$alert-warning-text:          $state-warning-text !default;
+$alert-warning-border:        $state-warning-border !default;
 
-$alert-danger-bg:             $state-danger-bg;
-$alert-danger-text:           $state-danger-text;
-$alert-danger-border:         $state-danger-border;
+$alert-danger-bg:             $state-danger-bg !default;
+$alert-danger-text:           $state-danger-text !default;
+$alert-danger-border:         $state-danger-border !default;
 
 
 //== Progress bars
@@ -640,22 +640,22 @@ $alert-danger-border:         $state-danger-border;
 //##
 
 //** Background color of the whole progress component
-$progress-bg:                 $gray-lighter;
+$progress-bg:                 $gray-lighter !default;
 //** Progress bar text color
-$progress-bar-color:          #fff;
+$progress-bar-color:          #fff !default;
 //** Variable for setting rounded corners on progress bar.
-$progress-border-radius:      $border-radius-base;
+$progress-border-radius:      $border-radius-base !default;
 
 //** Default progress bar color
-$progress-bar-bg:             $brand-primary;
+$progress-bar-bg:             $brand-primary !default;
 //** Success progress bar color
-$progress-bar-success-bg:     $brand-success;
+$progress-bar-success-bg:     $brand-success !default;
 //** Warning progress bar color
-$progress-bar-warning-bg:     $brand-warning;
+$progress-bar-warning-bg:     $brand-warning !default;
 //** Danger progress bar color
-$progress-bar-danger-bg:      $brand-danger;
+$progress-bar-danger-bg:      $brand-danger !default;
 //** Info progress bar color
-$progress-bar-info-bg:        $brand-info;
+$progress-bar-info-bg:        $brand-info !default;
 
 
 //== List group
@@ -663,72 +663,72 @@ $progress-bar-info-bg:        $brand-info;
 //##
 
 //** Background color on `.list-group-item`
-$list-group-bg:                 $gray-dark;
+$list-group-bg:                 $gray-dark !default;
 //** `.list-group-item` border color
-$list-group-border:             $gray;
+$list-group-border:             $gray !default;
 //** List group border radius
-$list-group-border-radius:      $border-radius-base;
+$list-group-border-radius:      $border-radius-base !default;
 
 //** Background color of single list items on hover
-$list-group-hover-bg:          transparent;
+$list-group-hover-bg:          transparent !default;
 //** Text color of active list items
-$list-group-active-color:       $component-active-color;
+$list-group-active-color:       $component-active-color !default;
 //** Background color of active list items
-$list-group-active-bg:          $component-active-bg;
+$list-group-active-bg:          $component-active-bg !default;
 //** Border color of active list elements
-$list-group-active-border:      $list-group-active-bg;
+$list-group-active-border:      $list-group-active-bg !default;
 //** Text color for content within active list items
-$list-group-active-text-color:  lighten($list-group-active-bg, 40%);
+$list-group-active-text-color:  lighten($list-group-active-bg, 40%) !default;
 
 //** Text color of disabled list items
-$list-group-disabled-color:      $gray-light;
+$list-group-disabled-color:      $gray-light !default;
 //** Background color of disabled list items
-$list-group-disabled-bg:         $gray-lighter;
+$list-group-disabled-bg:         $gray-lighter !default;
 //** Text color for content within disabled list items
-$list-group-disabled-text-color: $list-group-disabled-color;
+$list-group-disabled-text-color: $list-group-disabled-color !default;
 
-$list-group-link-color:         $link-color;
-$list-group-link-hover-color:   $list-group-link-color;
-$list-group-link-heading-color: darken($link-color, 5%);
+$list-group-link-color:         $link-color !default;
+$list-group-link-hover-color:   $list-group-link-color !default;
+$list-group-link-heading-color: darken($link-color, 5%) !default;
 
 
 //== Panels
 //
 //##
 
-$panel-bg:                    $gray-dark;
-$panel-body-padding:          15px;
-$panel-heading-padding:       10px 15px;
-$panel-footer-padding:        $panel-heading-padding;
-$panel-border-radius:         $border-radius-base;
+$panel-bg:                    $gray-dark !default;
+$panel-body-padding:          15px !default;
+$panel-heading-padding:       10px 15px !default;
+$panel-footer-padding:        $panel-heading-padding !default;
+$panel-border-radius:         $border-radius-base !default;
 
 //** Border color for elements within panels
-$panel-inner-border:          $gray;
-$panel-footer-bg:             $gray;
+$panel-inner-border:          $gray !default;
+$panel-footer-bg:             $gray !default;
 
-$panel-default-text:          $text-color;
-$panel-default-border:        $gray;
-$panel-default-heading-bg:    $gray-dark;
+$panel-default-text:          $text-color !default;
+$panel-default-border:        $gray !default;
+$panel-default-heading-bg:    $gray-dark !default;
 
-$panel-primary-text:          #fff;
-$panel-primary-border:        $brand-primary;
-$panel-primary-heading-bg:    $brand-primary;
+$panel-primary-text:          #fff !default;
+$panel-primary-border:        $brand-primary !default;
+$panel-primary-heading-bg:    $brand-primary !default;
 
-$panel-success-text:          $state-success-text;
-$panel-success-border:        $state-success-border;
-$panel-success-heading-bg:    $state-success-bg;
+$panel-success-text:          $state-success-text !default;
+$panel-success-border:        $state-success-border !default;
+$panel-success-heading-bg:    $state-success-bg !default;
 
-$panel-info-text:             $state-info-text;
-$panel-info-border:           $state-info-border;
-$panel-info-heading-bg:       $state-info-bg;
+$panel-info-text:             $state-info-text !default;
+$panel-info-border:           $state-info-border !default;
+$panel-info-heading-bg:       $state-info-bg !default;
 
-$panel-warning-text:          $state-warning-text;
-$panel-warning-border:        $state-warning-border;
-$panel-warning-heading-bg:    $state-warning-bg;
+$panel-warning-text:          $state-warning-text !default;
+$panel-warning-border:        $state-warning-border !default;
+$panel-warning-heading-bg:    $state-warning-bg !default;
 
-$panel-danger-text:           $state-danger-text;
-$panel-danger-border:         $state-danger-border;
-$panel-danger-heading-bg:     $state-danger-bg;
+$panel-danger-text:           $state-danger-text !default;
+$panel-danger-border:         $state-danger-border !default;
+$panel-danger-heading-bg:     $state-danger-bg !default;
 
 
 //== Thumbnails
@@ -736,103 +736,103 @@ $panel-danger-heading-bg:     $state-danger-bg;
 //##
 
 //** Padding around the thumbnail image
-$thumbnail-padding:           2px;
+$thumbnail-padding:           2px !default;
 //** Thumbnail background color
-$thumbnail-bg:                $body-bg;
+$thumbnail-bg:                $body-bg !default;
 //** Thumbnail border color
-$thumbnail-border:            $gray;
+$thumbnail-border:            $gray !default;
 //** Thumbnail border radius
-$thumbnail-border-radius:     $border-radius-base;
+$thumbnail-border-radius:     $border-radius-base !default;
 
 //** Custom text color for thumbnail captions
-$thumbnail-caption-color:     $text-color;
+$thumbnail-caption-color:     $text-color !default;
 //** Padding around the thumbnail caption
-$thumbnail-caption-padding:   9px;
+$thumbnail-caption-padding:   9px !default;
 
 
 //== Wells
 //
 //##
 
-$well-bg:                     $gray-dark;
-$well-border:                 transparent;
+$well-bg:                     $gray-dark !default;
+$well-border:                 transparent !default;
 
 
 //== Badges
 //
 //##
 
-$badge-color:                 #fff;
+$badge-color:                 #fff !default;
 //** Linked badge text color on hover
-$badge-link-hover-color:      #fff;
-$badge-bg:                    $gray;
+$badge-link-hover-color:      #fff !default;
+$badge-bg:                    $gray !default;
 
 //** Badge text color in active nav link
-$badge-active-color:          $brand-primary;
+$badge-active-color:          $brand-primary !default;
 //** Badge background color in active nav link
-$badge-active-bg:             #fff;
+$badge-active-bg:             #fff !default;
 
-$badge-font-weight:           bold;
-$badge-line-height:           1;
-$badge-border-radius:         10px;
+$badge-font-weight:           bold !default;
+$badge-line-height:           1 !default;
+$badge-border-radius:         10px !default;
 
 
 //== Breadcrumbs
 //
 //##
 
-$breadcrumb-padding-vertical:   8px;
-$breadcrumb-padding-horizontal: 15px;
+$breadcrumb-padding-vertical:   8px !default;
+$breadcrumb-padding-horizontal: 15px !default;
 //** Breadcrumb background color
-$breadcrumb-bg:                 $gray;
+$breadcrumb-bg:                 $gray !default;
 //** Breadcrumb text color
-$breadcrumb-color:              $text-color;
+$breadcrumb-color:              $text-color !default;
 //** Text color of current page in the breadcrumb
-$breadcrumb-active-color:       $gray-light;
+$breadcrumb-active-color:       $gray-light !default;
 //** Textual separator for between breadcrumb elements
-$breadcrumb-separator:          "/";
+$breadcrumb-separator:          "/" !default;
 
 
 //== Carousel
 //
 //##
 
-$carousel-text-shadow:                        0 1px 2px rgba(0,0,0,.6);
+$carousel-text-shadow:                        0 1px 2px rgba(0,0,0,.6) !default;
 
-$carousel-control-color:                      #fff;
-$carousel-control-width:                      15%;
-$carousel-control-opacity:                    .5;
-$carousel-control-font-size:                  20px;
+$carousel-control-color:                      #fff !default;
+$carousel-control-width:                      15% !default;
+$carousel-control-opacity:                    .5 !default;
+$carousel-control-font-size:                  20px !default;
 
-$carousel-indicator-active-bg:                #fff;
-$carousel-indicator-border-color:             #fff;
+$carousel-indicator-active-bg:                #fff !default;
+$carousel-indicator-border-color:             #fff !default;
 
-$carousel-caption-color:                      #fff;
+$carousel-caption-color:                      #fff !default;
 
 
 //== Close
 //
 //##
 
-$close-font-weight:           bold;
-$close-color:                 #fff;
-$close-text-shadow:           none;
+$close-font-weight:           bold !default;
+$close-color:                 #fff !default;
+$close-text-shadow:           none !default;
 
 
 //== Code
 //
 //##
 
-$code-color:                  #c7254e;
-$code-bg:                     #f9f2f4;
+$code-color:                  #c7254e !default;
+$code-bg:                     #f9f2f4 !default;
 
-$kbd-color:                   #fff;
-$kbd-bg:                      #333;
+$kbd-color:                   #fff !default;
+$kbd-bg:                      #333 !default;
 
-$pre-bg:                      $gray-lighter;
-$pre-color:                   $gray-dark;
-$pre-border-color:            #ccc;
-$pre-scrollable-max-height:   340px;
+$pre-bg:                      $gray-lighter !default;
+$pre-color:                   $gray-dark !default;
+$pre-border-color:            #ccc !default;
+$pre-scrollable-max-height:   340px !default;
 
 
 //== Type
@@ -840,22 +840,22 @@ $pre-scrollable-max-height:   340px;
 //##
 
 //** Horizontal offset for forms and lists.
-$component-offset-horizontal: 180px;
+$component-offset-horizontal: 180px !default;
 //** Text muted color
-$text-muted:                  $gray-light;
+$text-muted:                  $gray-light !default;
 //** Abbreviations and acronyms border color
-$abbr-border-color:           $gray-light;
+$abbr-border-color:           $gray-light !default;
 //** Headings small color
-$headings-small-color:        $gray-light;
+$headings-small-color:        $gray-light !default;
 //** Blockquote small color
-$blockquote-small-color:      $gray-light;
+$blockquote-small-color:      $gray-light !default;
 //** Blockquote font size
-$blockquote-font-size:        ($font-size-base * 1.25);
+$blockquote-font-size:        ($font-size-base * 1.25) !default;
 //** Blockquote border color
-$blockquote-border-color:     $gray;
+$blockquote-border-color:     $gray !default;
 //** Page header border color
-$page-header-border-color:    transparent;
+$page-header-border-color:    transparent !default;
 //** Width of horizontal description list titles
-$dl-horizontal-offset:        $component-offset-horizontal;
+$dl-horizontal-offset:        $component-offset-horizontal !default;
 //** Horizontal line color.
-$hr-border:                   $gray;
+$hr-border:                   $gray !default;
diff --git a/flatly/_variables.scss b/flatly/_variables.scss
index 892f9136..f7525415 100644
--- a/flatly/_variables.scss
+++ b/flatly/_variables.scss
@@ -7,18 +7,18 @@
 //
 //## Gray and brand colors for use across Bootstrap.
 
-$gray-base:              #000;
-$gray-darker:            lighten($gray-base, 13.5%); // #222
-$gray-dark:              #7b8a8b;   // #333
-$gray:                   #95a5a6; // #555
-$gray-light:             #b4bcc2;   // #999
-$gray-lighter:           #ecf0f1; // #eee
+$gray-base:              #000 !default;
+$gray-darker:            lighten($gray-base, 13.5%) !default; // #222
+$gray-dark:              #7b8a8b !default;   // #333
+$gray:                   #95a5a6 !default; // #555
+$gray-light:             #b4bcc2 !default;   // #999
+$gray-lighter:           #ecf0f1 !default; // #eee
 
-$brand-primary:         #2C3E50;
-$brand-success:         #18BC9C;
-$brand-info:            #3498DB;
-$brand-warning:         #F39C12;
-$brand-danger:          #E74C3C;
+$brand-primary:         #2C3E50 !default;
+$brand-success:         #18BC9C !default;
+$brand-info:            #3498DB !default;
+$brand-warning:         #F39C12 !default;
+$brand-danger:          #E74C3C !default;
 
 
 //== Scaffolding
@@ -26,49 +26,49 @@ $brand-danger:          #E74C3C;
 //## Settings for some of the most global styles.
 
 //** Background color for ``.
-$body-bg:               #fff;
+$body-bg:               #fff !default;
 //** Global text color on ``.
-$text-color:            $brand-primary;
+$text-color:            $brand-primary !default;
 
 //** Global textual link color.
-$link-color:            $brand-success;
+$link-color:            $brand-success !default;
 //** Link hover color set via `darken()` function.
-$link-hover-color:      $link-color;
+$link-hover-color:      $link-color !default;
 //** Link hover decoration.
-$link-hover-decoration: underline;
+$link-hover-decoration: underline !default;
 
 
 //== Typography
 //
 //## Font, line-height, and color for body text, headings, and more.
 
-$font-family-sans-serif:  "Lato", "Helvetica Neue", Helvetica, Arial, sans-serif;
-$font-family-serif:       Georgia, "Times New Roman", Times, serif;
+$font-family-sans-serif:  "Lato", "Helvetica Neue", Helvetica, Arial, sans-serif !default;
+$font-family-serif:       Georgia, "Times New Roman", Times, serif !default;
 //** Default monospace fonts for ``, ``, and `
`.
-$font-family-monospace:   Menlo, Monaco, Consolas, "Courier New", monospace;
-$font-family-base:        $font-family-sans-serif;
+$font-family-monospace:   Menlo, Monaco, Consolas, "Courier New", monospace !default;
+$font-family-base:        $font-family-sans-serif !default;
 
-$font-size-base:          15px;
-$font-size-large:         ceil(($font-size-base * 1.25)); // ~18px
-$font-size-small:         ceil(($font-size-base * 0.85)); // ~12px
+$font-size-base:          15px !default;
+$font-size-large:         ceil(($font-size-base * 1.25)) !default; // ~18px
+$font-size-small:         ceil(($font-size-base * 0.85)) !default; // ~12px
 
-$font-size-h1:            floor(($font-size-base * 2.6)); // ~36px
-$font-size-h2:            floor(($font-size-base * 2.15)); // ~30px
-$font-size-h3:            ceil(($font-size-base * 1.7)); // ~24px
-$font-size-h4:            ceil(($font-size-base * 1.25)); // ~18px
-$font-size-h5:            $font-size-base;
-$font-size-h6:            ceil(($font-size-base * 0.85)); // ~12px
+$font-size-h1:            floor(($font-size-base * 2.6)) !default; // ~36px
+$font-size-h2:            floor(($font-size-base * 2.15)) !default; // ~30px
+$font-size-h3:            ceil(($font-size-base * 1.7)) !default; // ~24px
+$font-size-h4:            ceil(($font-size-base * 1.25)) !default; // ~18px
+$font-size-h5:            $font-size-base !default;
+$font-size-h6:            ceil(($font-size-base * 0.85)) !default; // ~12px
 
 //** Unit-less `line-height` for use in components like buttons.
-$line-height-base:        1.428571429; // 20/14
+$line-height-base:        1.428571429 !default; // 20/14
 //** Computed "line-height" (`font-size` * `line-height`) for use with `margin`, `padding`, etc.
-$line-height-computed:    floor(($font-size-base * $line-height-base)); // ~20px
+$line-height-computed:    floor(($font-size-base * $line-height-base)) !default; // ~20px
 
 //** By default, this inherits from the ``.
-$headings-font-family:    $font-family-base;
-$headings-font-weight:    400;
-$headings-line-height:    1.1;
-$headings-color:          inherit;
+$headings-font-family:    $font-family-base !default;
+$headings-font-weight:    400 !default;
+$headings-line-height:    1.1 !default;
+$headings-color:          inherit !default;
 
 
 //== Iconography
@@ -76,45 +76,45 @@ $headings-color:          inherit;
 //## Specify custom location and filename of the included Glyphicons icon font. Useful for those including Bootstrap via Bower.
 
 //** Load fonts from this directory.
-$icon-font-path:          "../fonts/";
+$icon-font-path:          "../fonts/" !default;
 //** File name for all font files.
-$icon-font-name:          "glyphicons-halflings-regular";
+$icon-font-name:          "glyphicons-halflings-regular" !default;
 //** Element ID within SVG icon file.
-$icon-font-svg-id:        "glyphicons_halflingsregular";
+$icon-font-svg-id:        "glyphicons_halflingsregular" !default;
 
 
 //== Components
 //
 //## Define common padding and border radius sizes and more. Values based on 14px text and 1.428 line-height (~20px to start).
 
-$padding-base-vertical:     10px;
-$padding-base-horizontal:   15px;
+$padding-base-vertical:     10px !default;
+$padding-base-horizontal:   15px !default;
 
-$padding-large-vertical:    18px;
-$padding-large-horizontal:  27px;
+$padding-large-vertical:    18px !default;
+$padding-large-horizontal:  27px !default;
 
-$padding-small-vertical:    6px;
-$padding-small-horizontal:  9px;
+$padding-small-vertical:    6px !default;
+$padding-small-horizontal:  9px !default;
 
-$padding-xs-vertical:       1px;
-$padding-xs-horizontal:     5px;
+$padding-xs-vertical:       1px !default;
+$padding-xs-horizontal:     5px !default;
 
-$line-height-large:         1.3333333; // extra decimals for Win 8.1 Chrome
-$line-height-small:         1.5;
+$line-height-large:         1.3333333 !default; // extra decimals for Win 8.1 Chrome
+$line-height-small:         1.5 !default;
 
-$border-radius-base:        4px;
-$border-radius-large:       6px;
-$border-radius-small:       3px;
+$border-radius-base:        4px !default;
+$border-radius-large:       6px !default;
+$border-radius-small:       3px !default;
 
 //** Global color for active items (e.g., navs or dropdowns).
-$component-active-color:    #fff;
+$component-active-color:    #fff !default;
 //** Global background color for active items (e.g., navs or dropdowns).
-$component-active-bg:       $brand-primary;
+$component-active-bg:       $brand-primary !default;
 
 //** Width of the `border` for generating carets that indicator dropdowns.
-$caret-width-base:          4px;
+$caret-width-base:          4px !default;
 //** Carets increase slightly in size for larger components.
-$caret-width-large:         5px;
+$caret-width-large:         5px !default;
 
 
 //== Tables
@@ -122,53 +122,53 @@ $caret-width-large:         5px;
 //## Customizes the `.table` component with basic values, each used across all table variations.
 
 //** Padding for ``s and ``s.
-$table-cell-padding:            8px;
+$table-cell-padding:            8px !default;
 //** Padding for cells in `.table-condensed`.
-$table-condensed-cell-padding:  5px;
+$table-condensed-cell-padding:  5px !default;
 
 //** Default background color used for all tables.
-$table-bg:                      transparent;
+$table-bg:                      transparent !default;
 //** Background color used for `.table-striped`.
-$table-bg-accent:               #f9f9f9;
+$table-bg-accent:               #f9f9f9 !default;
 //** Background color used for `.table-hover`.
-$table-bg-hover:                $gray-lighter;
-$table-bg-active:               $table-bg-hover;
+$table-bg-hover:                $gray-lighter !default;
+$table-bg-active:               $table-bg-hover !default;
 
 //** Border color for table and cell borders.
-$table-border-color:            $gray-lighter;
+$table-border-color:            $gray-lighter !default;
 
 
 //== Buttons
 //
 //## For each of Bootstrap's buttons, define text, background and border color.
 
-$btn-font-weight:                normal;
+$btn-font-weight:                normal !default;
 
-$btn-default-color:              #fff;
-$btn-default-bg:                 $gray;
-$btn-default-border:             $btn-default-bg;
+$btn-default-color:              #fff !default;
+$btn-default-bg:                 $gray !default;
+$btn-default-border:             $btn-default-bg !default;
 
-$btn-primary-color:              $btn-default-color;
-$btn-primary-bg:                 $brand-primary;
-$btn-primary-border:             $btn-primary-bg;
+$btn-primary-color:              $btn-default-color !default;
+$btn-primary-bg:                 $brand-primary !default;
+$btn-primary-border:             $btn-primary-bg !default;
 
-$btn-success-color:              $btn-default-color;
-$btn-success-bg:                 $brand-success;
-$btn-success-border:             $btn-success-bg;
+$btn-success-color:              $btn-default-color !default;
+$btn-success-bg:                 $brand-success !default;
+$btn-success-border:             $btn-success-bg !default;
 
-$btn-info-color:                 $btn-default-color;
-$btn-info-bg:                    $brand-info;
-$btn-info-border:                $btn-info-bg;
+$btn-info-color:                 $btn-default-color !default;
+$btn-info-bg:                    $brand-info !default;
+$btn-info-border:                $btn-info-bg !default;
 
-$btn-warning-color:              $btn-default-color;
-$btn-warning-bg:                 $brand-warning;
-$btn-warning-border:             $btn-warning-bg;
+$btn-warning-color:              $btn-default-color !default;
+$btn-warning-bg:                 $brand-warning !default;
+$btn-warning-border:             $btn-warning-bg !default;
 
-$btn-danger-color:               $btn-default-color;
-$btn-danger-bg:                  $brand-danger;
-$btn-danger-border:              $btn-danger-bg;
+$btn-danger-color:               $btn-default-color !default;
+$btn-danger-bg:                  $brand-danger !default;
+$btn-danger-border:              $btn-danger-bg !default;
 
-$btn-link-disabled-color:        $gray-light;
+$btn-link-disabled-color:        $gray-light !default;
 
 
 //== Forms
@@ -176,50 +176,50 @@ $btn-link-disabled-color:        $gray-light;
 //##
 
 //** `` background color
-$input-bg:                       #fff;
+$input-bg:                       #fff !default;
 //** `` background color
-$input-bg-disabled:              $gray-lighter;
+$input-bg-disabled:              $gray-lighter !default;
 
 //** Text color for ``s
-$input-color:                    $text-color;
+$input-color:                    $text-color !default;
 //** `` border color
-$input-border:                   #dce4ec;
+$input-border:                   #dce4ec !default;
 
 // TODO: Rename `$input-border-radius` to `$input-border-radius-base` in v4
 //** Default `.form-control` border radius
 // This has no effect on ``s in CSS.
-$input-border-radius:            $border-radius-base;
+$input-border-radius:            $border-radius-base !default;
 //** Large `.form-control` border radius
-$input-border-radius-large:      $border-radius-large;
+$input-border-radius-large:      $border-radius-large !default;
 //** Small `.form-control` border radius
-$input-border-radius-small:      $border-radius-small;
+$input-border-radius-small:      $border-radius-small !default;
 
 //** Border color for inputs on focus
-$input-border-focus:             $brand-primary;
+$input-border-focus:             $brand-primary !default;
 
 //** Placeholder text color
-$input-color-placeholder:        #acb6c0;
+$input-color-placeholder:        #acb6c0 !default;
 
 //** Default `.form-control` height
-$input-height-base:              ($line-height-computed + ($padding-base-vertical * 2) + 4);
+$input-height-base:              ($line-height-computed + ($padding-base-vertical * 2) + 4) !default;
 //** Large `.form-control` height
-$input-height-large:             (ceil($font-size-large * $line-height-large) + ($padding-large-vertical * 2) + 4);
+$input-height-large:             (ceil($font-size-large * $line-height-large) + ($padding-large-vertical * 2) + 4) !default;
 //** Small `.form-control` height
-$input-height-small:             (floor($font-size-small * $line-height-small) + ($padding-small-vertical * 2) + 4);
+$input-height-small:             (floor($font-size-small * $line-height-small) + ($padding-small-vertical * 2) + 4) !default;
 
 //** `.form-group` margin
-$form-group-margin-bottom:       15px;
+$form-group-margin-bottom:       15px !default;
 
-$legend-color:                   $text-color;
-$legend-border-color:            transparent;
+$legend-color:                   $text-color !default;
+$legend-border-color:            transparent !default;
 
 //** Background color for textual input addons
-$input-group-addon-bg:           $gray-lighter;
+$input-group-addon-bg:           $gray-lighter !default;
 //** Border color for textual input addons
-$input-group-addon-border-color: $input-border;
+$input-group-addon-border-color: $input-border !default;
 
 //** Disabled cursor for form controls and buttons.
-$cursor-disabled:                not-allowed;
+$cursor-disabled:                not-allowed !default;
 
 
 //== Dropdowns
@@ -227,34 +227,34 @@ $cursor-disabled:                not-allowed;
 //## Dropdown menu container and contents.
 
 //** Background for the dropdown menu.
-$dropdown-bg:                    #fff;
+$dropdown-bg:                    #fff !default;
 //** Dropdown menu `border-color`.
-$dropdown-border:                rgba(0,0,0,.15);
+$dropdown-border:                rgba(0,0,0,.15) !default;
 //** Dropdown menu `border-color` **for IE8**.
-$dropdown-fallback-border:       #ccc;
+$dropdown-fallback-border:       #ccc !default;
 //** Divider color for between dropdown items.
-$dropdown-divider-bg:            #e5e5e5;
+$dropdown-divider-bg:            #e5e5e5 !default;
 
 //** Dropdown link text color.
-$dropdown-link-color:            $gray-dark;
+$dropdown-link-color:            $gray-dark !default;
 //** Hover color for dropdown links.
-$dropdown-link-hover-color:      #fff;
+$dropdown-link-hover-color:      #fff !default;
 //** Hover background for dropdown links.
-$dropdown-link-hover-bg:         $component-active-bg;
+$dropdown-link-hover-bg:         $component-active-bg !default;
 
 //** Active dropdown menu item text color.
-$dropdown-link-active-color:     #fff;
+$dropdown-link-active-color:     #fff !default;
 //** Active dropdown menu item background color.
-$dropdown-link-active-bg:        $component-active-bg;
+$dropdown-link-active-bg:        $component-active-bg !default;
 
 //** Disabled dropdown menu item background color.
-$dropdown-link-disabled-color:   $gray-light;
+$dropdown-link-disabled-color:   $gray-light !default;
 
 //** Text color for headers within dropdown menus.
-$dropdown-header-color:          $gray-light;
+$dropdown-header-color:          $gray-light !default;
 
 //** Deprecated `$dropdown-caret-color` as of v3.1.0
-$dropdown-caret-color:           #000;
+$dropdown-caret-color:           #000 !default;
 
 
 //-- Z-index master list
@@ -264,13 +264,13 @@ $dropdown-caret-color:           #000;
 //
 // Note: These variables are not generated into the Customizer.
 
-$zindex-navbar:            1000;
-$zindex-dropdown:          1000;
-$zindex-popover:           1060;
-$zindex-tooltip:           1070;
-$zindex-navbar-fixed:      1030;
-$zindex-modal-background:  1040;
-$zindex-modal:             1050;
+$zindex-navbar:            1000 !default;
+$zindex-dropdown:          1000 !default;
+$zindex-popover:           1060 !default;
+$zindex-tooltip:           1070 !default;
+$zindex-navbar-fixed:      1030 !default;
+$zindex-modal-background:  1040 !default;
+$zindex-modal:             1050 !default;
 
 
 //== Media queries breakpoints
@@ -279,37 +279,37 @@ $zindex-modal:             1050;
 
 // Extra small screen / phone
 //** Deprecated `$screen-xs` as of v3.0.1
-$screen-xs:                  480px;
+$screen-xs:                  480px !default;
 //** Deprecated `$screen-xs-min` as of v3.2.0
-$screen-xs-min:              $screen-xs;
+$screen-xs-min:              $screen-xs !default;
 //** Deprecated `$screen-phone` as of v3.0.1
-$screen-phone:               $screen-xs-min;
+$screen-phone:               $screen-xs-min !default;
 
 // Small screen / tablet
 //** Deprecated `$screen-sm` as of v3.0.1
-$screen-sm:                  768px;
-$screen-sm-min:              $screen-sm;
+$screen-sm:                  768px !default;
+$screen-sm-min:              $screen-sm !default;
 //** Deprecated `$screen-tablet` as of v3.0.1
-$screen-tablet:              $screen-sm-min;
+$screen-tablet:              $screen-sm-min !default;
 
 // Medium screen / desktop
 //** Deprecated `$screen-md` as of v3.0.1
-$screen-md:                  992px;
-$screen-md-min:              $screen-md;
+$screen-md:                  992px !default;
+$screen-md-min:              $screen-md !default;
 //** Deprecated `$screen-desktop` as of v3.0.1
-$screen-desktop:             $screen-md-min;
+$screen-desktop:             $screen-md-min !default;
 
 // Large screen / wide desktop
 //** Deprecated `$screen-lg` as of v3.0.1
-$screen-lg:                  1200px;
-$screen-lg-min:              $screen-lg;
+$screen-lg:                  1200px !default;
+$screen-lg-min:              $screen-lg !default;
 //** Deprecated `$screen-lg-desktop` as of v3.0.1
-$screen-lg-desktop:          $screen-lg-min;
+$screen-lg-desktop:          $screen-lg-min !default;
 
 // So media queries don't overlap when required, provide a maximum
-$screen-xs-max:              ($screen-sm-min - 1);
-$screen-sm-max:              ($screen-md-min - 1);
-$screen-md-max:              ($screen-lg-min - 1);
+$screen-xs-max:              ($screen-sm-min - 1) !default;
+$screen-sm-max:              ($screen-md-min - 1) !default;
+$screen-md-max:              ($screen-lg-min - 1) !default;
 
 
 //== Grid system
@@ -317,14 +317,14 @@ $screen-md-max:              ($screen-lg-min - 1);
 //## Define your custom responsive grid.
 
 //** Number of columns in the grid.
-$grid-columns:              12;
+$grid-columns:              12 !default;
 //** Padding between columns. Gets divided in half for the left and right.
-$grid-gutter-width:         30px;
+$grid-gutter-width:         30px !default;
 // Navbar collapse
 //** Point at which the navbar becomes uncollapsed.
-$grid-float-breakpoint:     $screen-sm-min;
+$grid-float-breakpoint:     $screen-sm-min !default;
 //** Point at which the navbar begins collapsing.
-$grid-float-breakpoint-max: ($grid-float-breakpoint - 1);
+$grid-float-breakpoint-max: ($grid-float-breakpoint - 1) !default;
 
 
 //== Container sizes
@@ -332,19 +332,19 @@ $grid-float-breakpoint-max: ($grid-float-breakpoint - 1);
 //## Define the maximum width of `.container` for different screen sizes.
 
 // Small screen / tablet
-$container-tablet:             (720px + $grid-gutter-width);
+$container-tablet:             (720px + $grid-gutter-width) !default;
 //** For `$screen-sm-min` and up.
-$container-sm:                 $container-tablet;
+$container-sm:                 $container-tablet !default;
 
 // Medium screen / desktop
-$container-desktop:            (940px + $grid-gutter-width);
+$container-desktop:            (940px + $grid-gutter-width) !default;
 //** For `$screen-md-min` and up.
-$container-md:                 $container-desktop;
+$container-md:                 $container-desktop !default;
 
 // Large screen / wide desktop
-$container-large-desktop:      (1140px + $grid-gutter-width);
+$container-large-desktop:      (1140px + $grid-gutter-width) !default;
 //** For `$screen-lg-min` and up.
-$container-lg:                 $container-large-desktop;
+$container-lg:                 $container-large-desktop !default;
 
 
 //== Navbar
@@ -352,61 +352,61 @@ $container-lg:                 $container-large-desktop;
 //##
 
 // Basics of a navbar
-$navbar-height:                    60px;
-$navbar-margin-bottom:             $line-height-computed;
-$navbar-border-radius:             $border-radius-base;
-$navbar-padding-horizontal:        floor(($grid-gutter-width / 2));
-$navbar-padding-vertical:          (($navbar-height - $line-height-computed) / 2);
-$navbar-collapse-max-height:       340px;
+$navbar-height:                    60px !default;
+$navbar-margin-bottom:             $line-height-computed !default;
+$navbar-border-radius:             $border-radius-base !default;
+$navbar-padding-horizontal:        floor(($grid-gutter-width / 2)) !default;
+$navbar-padding-vertical:          (($navbar-height - $line-height-computed) / 2) !default;
+$navbar-collapse-max-height:       340px !default;
 
-$navbar-default-color:             #777;
-$navbar-default-bg:                $brand-primary;
-$navbar-default-border:            transparent;
+$navbar-default-color:             #777 !default;
+$navbar-default-bg:                $brand-primary !default;
+$navbar-default-border:            transparent !default;
 
 // Navbar links
-$navbar-default-link-color:                #fff;
-$navbar-default-link-hover-color:          $brand-success;
-$navbar-default-link-hover-bg:             transparent;
-$navbar-default-link-active-color:         #fff;
-$navbar-default-link-active-bg:            darken($navbar-default-bg, 10%);
-$navbar-default-link-disabled-color:       #ccc;
-$navbar-default-link-disabled-bg:          transparent;
+$navbar-default-link-color:                #fff !default;
+$navbar-default-link-hover-color:          $brand-success !default;
+$navbar-default-link-hover-bg:             transparent !default;
+$navbar-default-link-active-color:         #fff !default;
+$navbar-default-link-active-bg:            darken($navbar-default-bg, 10%) !default;
+$navbar-default-link-disabled-color:       #ccc !default;
+$navbar-default-link-disabled-bg:          transparent !default;
 
 // Navbar brand label
-$navbar-default-brand-color:               $navbar-default-link-color;
-$navbar-default-brand-hover-color:         $navbar-default-link-hover-color;
-$navbar-default-brand-hover-bg:            transparent;
+$navbar-default-brand-color:               $navbar-default-link-color !default;
+$navbar-default-brand-hover-color:         $navbar-default-link-hover-color !default;
+$navbar-default-brand-hover-bg:            transparent !default;
 
 // Navbar toggle
-$navbar-default-toggle-hover-bg:           darken($navbar-default-bg, 10%);
-$navbar-default-toggle-icon-bar-bg:        #fff;
-$navbar-default-toggle-border-color:       darken($navbar-default-bg, 10%);
+$navbar-default-toggle-hover-bg:           darken($navbar-default-bg, 10%) !default;
+$navbar-default-toggle-icon-bar-bg:        #fff !default;
+$navbar-default-toggle-border-color:       darken($navbar-default-bg, 10%) !default;
 
 
 // Inverted navbar
 // Reset inverted navbar basics
-$navbar-inverse-color:                      #fff;
-$navbar-inverse-bg:                         $brand-success;
-$navbar-inverse-border:                     transparent;
+$navbar-inverse-color:                      #fff !default;
+$navbar-inverse-bg:                         $brand-success !default;
+$navbar-inverse-border:                     transparent !default;
 
 // Inverted navbar links
-$navbar-inverse-link-color:                 #fff;
-$navbar-inverse-link-hover-color:           $brand-primary;
-$navbar-inverse-link-hover-bg:              transparent;
-$navbar-inverse-link-active-color:          #fff;
-$navbar-inverse-link-active-bg:             darken($navbar-inverse-bg, 5%);
-$navbar-inverse-link-disabled-color:        #ccc;
-$navbar-inverse-link-disabled-bg:           transparent;
+$navbar-inverse-link-color:                 #fff !default;
+$navbar-inverse-link-hover-color:           $brand-primary !default;
+$navbar-inverse-link-hover-bg:              transparent !default;
+$navbar-inverse-link-active-color:          #fff !default;
+$navbar-inverse-link-active-bg:             darken($navbar-inverse-bg, 5%) !default;
+$navbar-inverse-link-disabled-color:        #ccc !default;
+$navbar-inverse-link-disabled-bg:           transparent !default;
 
 // Inverted navbar brand label
-$navbar-inverse-brand-color:                $navbar-inverse-link-color;
-$navbar-inverse-brand-hover-color:          $navbar-inverse-link-hover-color;
-$navbar-inverse-brand-hover-bg:             transparent;
+$navbar-inverse-brand-color:                $navbar-inverse-link-color !default;
+$navbar-inverse-brand-hover-color:          $navbar-inverse-link-hover-color !default;
+$navbar-inverse-brand-hover-bg:             transparent !default;
 
 // Inverted navbar toggle
-$navbar-inverse-toggle-hover-bg:            darken($navbar-inverse-bg, 10%);
-$navbar-inverse-toggle-icon-bar-bg:         #fff;
-$navbar-inverse-toggle-border-color:        darken($navbar-inverse-bg, 10%);
+$navbar-inverse-toggle-hover-bg:            darken($navbar-inverse-bg, 10%) !default;
+$navbar-inverse-toggle-icon-bar-bg:         #fff !default;
+$navbar-inverse-toggle-border-color:        darken($navbar-inverse-bg, 10%) !default;
 
 
 //== Navs
@@ -414,97 +414,97 @@ $navbar-inverse-toggle-border-color:        darken($navbar-inverse-bg, 10%);
 //##
 
 //=== Shared nav styles
-$nav-link-padding:                          10px 15px;
-$nav-link-hover-bg:                         $gray-lighter;
+$nav-link-padding:                          10px 15px !default;
+$nav-link-hover-bg:                         $gray-lighter !default;
 
-$nav-disabled-link-color:                   $gray-light;
-$nav-disabled-link-hover-color:             $gray-light;
+$nav-disabled-link-color:                   $gray-light !default;
+$nav-disabled-link-hover-color:             $gray-light !default;
 
 //== Tabs
-$nav-tabs-border-color:                     $gray-lighter;
+$nav-tabs-border-color:                     $gray-lighter !default;
 
-$nav-tabs-link-hover-border-color:          $gray-lighter;
+$nav-tabs-link-hover-border-color:          $gray-lighter !default;
 
-$nav-tabs-active-link-hover-bg:             $body-bg;
-$nav-tabs-active-link-hover-color:          $brand-primary;
-$nav-tabs-active-link-hover-border-color:   $gray-lighter;
+$nav-tabs-active-link-hover-bg:             $body-bg !default;
+$nav-tabs-active-link-hover-color:          $brand-primary !default;
+$nav-tabs-active-link-hover-border-color:   $gray-lighter !default;
 
-$nav-tabs-justified-link-border-color:            $gray-lighter;
-$nav-tabs-justified-active-link-border-color:     $body-bg;
+$nav-tabs-justified-link-border-color:            $gray-lighter !default;
+$nav-tabs-justified-active-link-border-color:     $body-bg !default;
 
 //== Pills
-$nav-pills-border-radius:                   $border-radius-base;
-$nav-pills-active-link-hover-bg:            $component-active-bg;
-$nav-pills-active-link-hover-color:         $component-active-color;
+$nav-pills-border-radius:                   $border-radius-base !default;
+$nav-pills-active-link-hover-bg:            $component-active-bg !default;
+$nav-pills-active-link-hover-color:         $component-active-color !default;
 
 
 //== Pagination
 //
 //##
 
-$pagination-color:                     #fff;
-$pagination-bg:                        $brand-success;
-$pagination-border:                    transparent;
+$pagination-color:                     #fff !default;
+$pagination-bg:                        $brand-success !default;
+$pagination-border:                    transparent !default;
 
-$pagination-hover-color:               #fff;
-$pagination-hover-bg:                  darken($brand-success, 15%);
-$pagination-hover-border:              transparent;
+$pagination-hover-color:               #fff !default;
+$pagination-hover-bg:                  darken($brand-success, 15%) !default;
+$pagination-hover-border:              transparent !default;
 
-$pagination-active-color:              #fff;
-$pagination-active-bg:                 darken($brand-success, 15%);
-$pagination-active-border:             transparent;
+$pagination-active-color:              #fff !default;
+$pagination-active-bg:                 darken($brand-success, 15%) !default;
+$pagination-active-border:             transparent !default;
 
-$pagination-disabled-color:            $gray-lighter;
-$pagination-disabled-bg:               lighten($brand-success, 15%);
-$pagination-disabled-border:           transparent;
+$pagination-disabled-color:            $gray-lighter !default;
+$pagination-disabled-bg:               lighten($brand-success, 15%) !default;
+$pagination-disabled-border:           transparent !default;
 
 
 //== Pager
 //
 //##
 
-$pager-bg:                             $pagination-bg;
-$pager-border:                         $pagination-border;
-$pager-border-radius:                  15px;
+$pager-bg:                             $pagination-bg !default;
+$pager-border:                         $pagination-border !default;
+$pager-border-radius:                  15px !default;
 
-$pager-hover-bg:                       $pagination-hover-bg;
+$pager-hover-bg:                       $pagination-hover-bg !default;
 
-$pager-active-bg:                      $pagination-active-bg;
-$pager-active-color:                   $pagination-active-color;
+$pager-active-bg:                      $pagination-active-bg !default;
+$pager-active-color:                   $pagination-active-color !default;
 
-$pager-disabled-color:                 #fff;
+$pager-disabled-color:                 #fff !default;
 
 
 //== Jumbotron
 //
 //##
 
-$jumbotron-padding:              30px;
-$jumbotron-color:                inherit;
-$jumbotron-bg:                   $gray-lighter;
-$jumbotron-heading-color:        inherit;
-$jumbotron-font-size:            ceil(($font-size-base * 1.5));
+$jumbotron-padding:              30px !default;
+$jumbotron-color:                inherit !default;
+$jumbotron-bg:                   $gray-lighter !default;
+$jumbotron-heading-color:        inherit !default;
+$jumbotron-font-size:            ceil(($font-size-base * 1.5)) !default;
 
 
 //== Form states and alerts
 //
 //## Define colors for form feedback states and, by default, alerts.
 
-$state-success-text:             #fff;
-$state-success-bg:               $brand-success;
-$state-success-border:           $brand-success;
+$state-success-text:             #fff !default;
+$state-success-bg:               $brand-success !default;
+$state-success-border:           $brand-success !default;
 
-$state-info-text:                #fff;
-$state-info-bg:                  $brand-info;
-$state-info-border:              $brand-info;
+$state-info-text:                #fff !default;
+$state-info-bg:                  $brand-info !default;
+$state-info-border:              $brand-info !default;
 
-$state-warning-text:             #fff;
-$state-warning-bg:               $brand-warning;
-$state-warning-border:           $brand-warning;
+$state-warning-text:             #fff !default;
+$state-warning-bg:               $brand-warning !default;
+$state-warning-border:           $brand-warning !default;
 
-$state-danger-text:              #fff;
-$state-danger-bg:                $brand-danger;
-$state-danger-border:            $brand-danger;
+$state-danger-text:              #fff !default;
+$state-danger-bg:                $brand-danger !default;
+$state-danger-border:            $brand-danger !default;
 
 
 //== Tooltips
@@ -512,17 +512,17 @@ $state-danger-border:            $brand-danger;
 //##
 
 //** Tooltip max width
-$tooltip-max-width:           200px;
+$tooltip-max-width:           200px !default;
 //** Tooltip text color
-$tooltip-color:               #fff;
+$tooltip-color:               #fff !default;
 //** Tooltip background color
-$tooltip-bg:                  #000;
-$tooltip-opacity:             .9;
+$tooltip-bg:                  #000 !default;
+$tooltip-opacity:             .9 !default;
 
 //** Tooltip arrow width
-$tooltip-arrow-width:         5px;
+$tooltip-arrow-width:         5px !default;
 //** Tooltip arrow color
-$tooltip-arrow-color:         $tooltip-bg;
+$tooltip-arrow-color:         $tooltip-bg !default;
 
 
 //== Popovers
@@ -530,28 +530,28 @@ $tooltip-arrow-color:         $tooltip-bg;
 //##
 
 //** Popover body background color
-$popover-bg:                          #fff;
+$popover-bg:                          #fff !default;
 //** Popover maximum width
-$popover-max-width:                   276px;
+$popover-max-width:                   276px !default;
 //** Popover border color
-$popover-border-color:                rgba(0,0,0,.2);
+$popover-border-color:                rgba(0,0,0,.2) !default;
 //** Popover fallback border color
-$popover-fallback-border-color:       #ccc;
+$popover-fallback-border-color:       #ccc !default;
 
 //** Popover title background color
-$popover-title-bg:                    darken($popover-bg, 3%);
+$popover-title-bg:                    darken($popover-bg, 3%) !default;
 
 //** Popover arrow width
-$popover-arrow-width:                 10px;
+$popover-arrow-width:                 10px !default;
 //** Popover arrow color
-$popover-arrow-color:                 $popover-bg;
+$popover-arrow-color:                 $popover-bg !default;
 
 //** Popover outer arrow width
-$popover-arrow-outer-width:           ($popover-arrow-width + 1);
+$popover-arrow-outer-width:           ($popover-arrow-width + 1) !default;
 //** Popover outer arrow color
-$popover-arrow-outer-color:           fadein($popover-border-color, 5%);
+$popover-arrow-outer-color:           fadein($popover-border-color, 5%) !default;
 //** Popover outer arrow fallback color
-$popover-arrow-outer-fallback-color:  darken($popover-fallback-border-color, 20%);
+$popover-arrow-outer-fallback-color:  darken($popover-fallback-border-color, 20%) !default;
 
 
 //== Labels
@@ -559,22 +559,22 @@ $popover-arrow-outer-fallback-color:  darken($popover-fallback-border-color, 20%
 //##
 
 //** Default label background color
-$label-default-bg:            $btn-default-bg;
+$label-default-bg:            $btn-default-bg !default;
 //** Primary label background color
-$label-primary-bg:            $brand-primary;
+$label-primary-bg:            $brand-primary !default;
 //** Success label background color
-$label-success-bg:            $brand-success;
+$label-success-bg:            $brand-success !default;
 //** Info label background color
-$label-info-bg:               $brand-info;
+$label-info-bg:               $brand-info !default;
 //** Warning label background color
-$label-warning-bg:            $brand-warning;
+$label-warning-bg:            $brand-warning !default;
 //** Danger label background color
-$label-danger-bg:             $brand-danger;
+$label-danger-bg:             $brand-danger !default;
 
 //** Default label text color
-$label-color:                 #fff;
+$label-color:                 #fff !default;
 //** Default text color of a linked label
-$label-link-hover-color:      #fff;
+$label-link-hover-color:      #fff !default;
 
 
 //== Modals
@@ -582,57 +582,57 @@ $label-link-hover-color:      #fff;
 //##
 
 //** Padding applied to the modal body
-$modal-inner-padding:         20px;
+$modal-inner-padding:         20px !default;
 
 //** Padding applied to the modal title
-$modal-title-padding:         15px;
+$modal-title-padding:         15px !default;
 //** Modal title line-height
-$modal-title-line-height:     $line-height-base;
+$modal-title-line-height:     $line-height-base !default;
 
 //** Background color of modal content area
-$modal-content-bg:                             #fff;
+$modal-content-bg:                             #fff !default;
 //** Modal content border color
-$modal-content-border-color:                   rgba(0,0,0,.2);
+$modal-content-border-color:                   rgba(0,0,0,.2) !default;
 //** Modal content border color **for IE8**
-$modal-content-fallback-border-color:          #999;
+$modal-content-fallback-border-color:          #999 !default;
 
 //** Modal backdrop background color
-$modal-backdrop-bg:           #000;
+$modal-backdrop-bg:           #000 !default;
 //** Modal backdrop opacity
-$modal-backdrop-opacity:      .5;
+$modal-backdrop-opacity:      .5 !default;
 //** Modal header border color
-$modal-header-border-color:   #e5e5e5;
+$modal-header-border-color:   #e5e5e5 !default;
 //** Modal footer border color
-$modal-footer-border-color:   $modal-header-border-color;
+$modal-footer-border-color:   $modal-header-border-color !default;
 
-$modal-lg:                    900px;
-$modal-md:                    600px;
-$modal-sm:                    300px;
+$modal-lg:                    900px !default;
+$modal-md:                    600px !default;
+$modal-sm:                    300px !default;
 
 
 //== Alerts
 //
 //## Define alert colors, border radius, and padding.
 
-$alert-padding:               15px;
-$alert-border-radius:         $border-radius-base;
-$alert-link-font-weight:      bold;
+$alert-padding:               15px !default;
+$alert-border-radius:         $border-radius-base !default;
+$alert-link-font-weight:      bold !default;
 
-$alert-success-bg:            $state-success-bg;
-$alert-success-text:          $state-success-text;
-$alert-success-border:        $state-success-border;
+$alert-success-bg:            $state-success-bg !default;
+$alert-success-text:          $state-success-text !default;
+$alert-success-border:        $state-success-border !default;
 
-$alert-info-bg:               $state-info-bg;
-$alert-info-text:             $state-info-text;
-$alert-info-border:           $state-info-border;
+$alert-info-bg:               $state-info-bg !default;
+$alert-info-text:             $state-info-text !default;
+$alert-info-border:           $state-info-border !default;
 
-$alert-warning-bg:            $state-warning-bg;
-$alert-warning-text:          $state-warning-text;
-$alert-warning-border:        $state-warning-border;
+$alert-warning-bg:            $state-warning-bg !default;
+$alert-warning-text:          $state-warning-text !default;
+$alert-warning-border:        $state-warning-border !default;
 
-$alert-danger-bg:             $state-danger-bg;
-$alert-danger-text:           $state-danger-text;
-$alert-danger-border:         $state-danger-border;
+$alert-danger-bg:             $state-danger-bg !default;
+$alert-danger-text:           $state-danger-text !default;
+$alert-danger-border:         $state-danger-border !default;
 
 
 //== Progress bars
@@ -640,22 +640,22 @@ $alert-danger-border:         $state-danger-border;
 //##
 
 //** Background color of the whole progress component
-$progress-bg:                 $gray-lighter;
+$progress-bg:                 $gray-lighter !default;
 //** Progress bar text color
-$progress-bar-color:          #fff;
+$progress-bar-color:          #fff !default;
 //** Variable for setting rounded corners on progress bar.
-$progress-border-radius:      $border-radius-base;
+$progress-border-radius:      $border-radius-base !default;
 
 //** Default progress bar color
-$progress-bar-bg:             $brand-primary;
+$progress-bar-bg:             $brand-primary !default;
 //** Success progress bar color
-$progress-bar-success-bg:     $brand-success;
+$progress-bar-success-bg:     $brand-success !default;
 //** Warning progress bar color
-$progress-bar-warning-bg:     $brand-warning;
+$progress-bar-warning-bg:     $brand-warning !default;
 //** Danger progress bar color
-$progress-bar-danger-bg:      $brand-danger;
+$progress-bar-danger-bg:      $brand-danger !default;
 //** Info progress bar color
-$progress-bar-info-bg:        $brand-info;
+$progress-bar-info-bg:        $brand-info !default;
 
 
 //== List group
@@ -663,72 +663,72 @@ $progress-bar-info-bg:        $brand-info;
 //##
 
 //** Background color on `.list-group-item`
-$list-group-bg:                 #fff;
+$list-group-bg:                 #fff !default;
 //** `.list-group-item` border color
-$list-group-border:             $gray-lighter;
+$list-group-border:             $gray-lighter !default;
 //** List group border radius
-$list-group-border-radius:      $border-radius-base;
+$list-group-border-radius:      $border-radius-base !default;
 
 //** Background color of single list items on hover
-$list-group-hover-bg:           $gray-lighter;
+$list-group-hover-bg:           $gray-lighter !default;
 //** Text color of active list items
-$list-group-active-color:       $component-active-color;
+$list-group-active-color:       $component-active-color !default;
 //** Background color of active list items
-$list-group-active-bg:          $component-active-bg;
+$list-group-active-bg:          $component-active-bg !default;
 //** Border color of active list elements
-$list-group-active-border:      $list-group-active-bg;
+$list-group-active-border:      $list-group-active-bg !default;
 //** Text color for content within active list items
-$list-group-active-text-color:  lighten($list-group-active-bg, 40%);
+$list-group-active-text-color:  lighten($list-group-active-bg, 40%) !default;
 
 //** Text color of disabled list items
-$list-group-disabled-color:      $gray-light;
+$list-group-disabled-color:      $gray-light !default;
 //** Background color of disabled list items
-$list-group-disabled-bg:         $gray-lighter;
+$list-group-disabled-bg:         $gray-lighter !default;
 //** Text color for content within disabled list items
-$list-group-disabled-text-color: $list-group-disabled-color;
+$list-group-disabled-text-color: $list-group-disabled-color !default;
 
-$list-group-link-color:         #555;
-$list-group-link-hover-color:   $list-group-link-color;
-$list-group-link-heading-color: #333;
+$list-group-link-color:         #555 !default;
+$list-group-link-hover-color:   $list-group-link-color !default;
+$list-group-link-heading-color: #333 !default;
 
 
 //== Panels
 //
 //##
 
-$panel-bg:                    #fff;
-$panel-body-padding:          15px;
-$panel-heading-padding:       10px 15px;
-$panel-footer-padding:        $panel-heading-padding;
-$panel-border-radius:         $border-radius-base;
+$panel-bg:                    #fff !default;
+$panel-body-padding:          15px !default;
+$panel-heading-padding:       10px 15px !default;
+$panel-footer-padding:        $panel-heading-padding !default;
+$panel-border-radius:         $border-radius-base !default;
 
 //** Border color for elements within panels
-$panel-inner-border:          $gray-lighter;
-$panel-footer-bg:             $gray-lighter;
+$panel-inner-border:          $gray-lighter !default;
+$panel-footer-bg:             $gray-lighter !default;
 
-$panel-default-text:          $text-color;
-$panel-default-border:        $gray-lighter;
-$panel-default-heading-bg:    $gray-lighter;
+$panel-default-text:          $text-color !default;
+$panel-default-border:        $gray-lighter !default;
+$panel-default-heading-bg:    $gray-lighter !default;
 
-$panel-primary-text:          #fff;
-$panel-primary-border:        $brand-primary;
-$panel-primary-heading-bg:    $brand-primary;
+$panel-primary-text:          #fff !default;
+$panel-primary-border:        $brand-primary !default;
+$panel-primary-heading-bg:    $brand-primary !default;
 
-$panel-success-text:          $state-success-text;
-$panel-success-border:        $state-success-border;
-$panel-success-heading-bg:    $state-success-bg;
+$panel-success-text:          $state-success-text !default;
+$panel-success-border:        $state-success-border !default;
+$panel-success-heading-bg:    $state-success-bg !default;
 
-$panel-info-text:             $state-info-text;
-$panel-info-border:           $state-info-border;
-$panel-info-heading-bg:       $state-info-bg;
+$panel-info-text:             $state-info-text !default;
+$panel-info-border:           $state-info-border !default;
+$panel-info-heading-bg:       $state-info-bg !default;
 
-$panel-warning-text:          $state-warning-text;
-$panel-warning-border:        $state-warning-border;
-$panel-warning-heading-bg:    $state-warning-bg;
+$panel-warning-text:          $state-warning-text !default;
+$panel-warning-border:        $state-warning-border !default;
+$panel-warning-heading-bg:    $state-warning-bg !default;
 
-$panel-danger-text:           $state-danger-text;
-$panel-danger-border:         $state-danger-border;
-$panel-danger-heading-bg:     $state-danger-bg;
+$panel-danger-text:           $state-danger-text !default;
+$panel-danger-border:         $state-danger-border !default;
+$panel-danger-heading-bg:     $state-danger-bg !default;
 
 
 //== Thumbnails
@@ -736,103 +736,103 @@ $panel-danger-heading-bg:     $state-danger-bg;
 //##
 
 //** Padding around the thumbnail image
-$thumbnail-padding:           4px;
+$thumbnail-padding:           4px !default;
 //** Thumbnail background color
-$thumbnail-bg:                $body-bg;
+$thumbnail-bg:                $body-bg !default;
 //** Thumbnail border color
-$thumbnail-border:            $gray-lighter;
+$thumbnail-border:            $gray-lighter !default;
 //** Thumbnail border radius
-$thumbnail-border-radius:     $border-radius-base;
+$thumbnail-border-radius:     $border-radius-base !default;
 
 //** Custom text color for thumbnail captions
-$thumbnail-caption-color:     $text-color;
+$thumbnail-caption-color:     $text-color !default;
 //** Padding around the thumbnail caption
-$thumbnail-caption-padding:   9px;
+$thumbnail-caption-padding:   9px !default;
 
 
 //== Wells
 //
 //##
 
-$well-bg:                     $gray-lighter;
-$well-border:                 transparent;
+$well-bg:                     $gray-lighter !default;
+$well-border:                 transparent !default;
 
 
 //== Badges
 //
 //##
 
-$badge-color:                 #fff;
+$badge-color:                 #fff !default;
 //** Linked badge text color on hover
-$badge-link-hover-color:      #fff;
-$badge-bg:                    $brand-primary;
+$badge-link-hover-color:      #fff !default;
+$badge-bg:                    $brand-primary !default;
 
 //** Badge text color in active nav link
-$badge-active-color:          $brand-primary;
+$badge-active-color:          $brand-primary !default;
 //** Badge background color in active nav link
-$badge-active-bg:             #fff;
+$badge-active-bg:             #fff !default;
 
-$badge-font-weight:           bold;
-$badge-line-height:           1;
-$badge-border-radius:         10px;
+$badge-font-weight:           bold !default;
+$badge-line-height:           1 !default;
+$badge-border-radius:         10px !default;
 
 
 //== Breadcrumbs
 //
 //##
 
-$breadcrumb-padding-vertical:   8px;
-$breadcrumb-padding-horizontal: 15px;
+$breadcrumb-padding-vertical:   8px !default;
+$breadcrumb-padding-horizontal: 15px !default;
 //** Breadcrumb background color
-$breadcrumb-bg:                 $gray-lighter;
+$breadcrumb-bg:                 $gray-lighter !default;
 //** Breadcrumb text color
-$breadcrumb-color:              #ccc;
+$breadcrumb-color:              #ccc !default;
 //** Text color of current page in the breadcrumb
-$breadcrumb-active-color:       $gray;
+$breadcrumb-active-color:       $gray !default;
 //** Textual separator for between breadcrumb elements
-$breadcrumb-separator:          "/";
+$breadcrumb-separator:          "/" !default;
 
 
 //== Carousel
 //
 //##
 
-$carousel-text-shadow:                        0 1px 2px rgba(0,0,0,.6);
+$carousel-text-shadow:                        0 1px 2px rgba(0,0,0,.6) !default;
 
-$carousel-control-color:                      #fff;
-$carousel-control-width:                      15%;
-$carousel-control-opacity:                    .5;
-$carousel-control-font-size:                  20px;
+$carousel-control-color:                      #fff !default;
+$carousel-control-width:                      15% !default;
+$carousel-control-opacity:                    .5 !default;
+$carousel-control-font-size:                  20px !default;
 
-$carousel-indicator-active-bg:                #fff;
-$carousel-indicator-border-color:             #fff;
+$carousel-indicator-active-bg:                #fff !default;
+$carousel-indicator-border-color:             #fff !default;
 
-$carousel-caption-color:                      #fff;
+$carousel-caption-color:                      #fff !default;
 
 
 //== Close
 //
 //##
 
-$close-font-weight:           bold;
-$close-color:                 #000;
-$close-text-shadow:           none;
+$close-font-weight:           bold !default;
+$close-color:                 #000 !default;
+$close-text-shadow:           none !default;
 
 
 //== Code
 //
 //##
 
-$code-color:                  #c7254e;
-$code-bg:                     #f9f2f4;
+$code-color:                  #c7254e !default;
+$code-bg:                     #f9f2f4 !default;
 
-$kbd-color:                   #fff;
-$kbd-bg:                      #333;
+$kbd-color:                   #fff !default;
+$kbd-bg:                      #333 !default;
 
-$pre-bg:                      $gray-lighter;
-$pre-color:                   $gray-dark;
-$pre-border-color:            #ccc;
-$pre-scrollable-max-height:   340px;
+$pre-bg:                      $gray-lighter !default;
+$pre-color:                   $gray-dark !default;
+$pre-border-color:            #ccc !default;
+$pre-scrollable-max-height:   340px !default;
 
 
 //== Type
@@ -840,22 +840,22 @@ $pre-scrollable-max-height:   340px;
 //##
 
 //** Horizontal offset for forms and lists.
-$component-offset-horizontal: 180px;
+$component-offset-horizontal: 180px !default;
 //** Text muted color
-$text-muted:                  $gray-light;
+$text-muted:                  $gray-light !default;
 //** Abbreviations and acronyms border color
-$abbr-border-color:           $gray-light;
+$abbr-border-color:           $gray-light !default;
 //** Headings small color
-$headings-small-color:        $gray-light;
+$headings-small-color:        $gray-light !default;
 //** Blockquote small color
-$blockquote-small-color:      $gray-light;
+$blockquote-small-color:      $gray-light !default;
 //** Blockquote font size
-$blockquote-font-size:        ($font-size-base * 1.25);
+$blockquote-font-size:        ($font-size-base * 1.25) !default;
 //** Blockquote border color
-$blockquote-border-color:     $gray-lighter;
+$blockquote-border-color:     $gray-lighter !default;
 //** Page header border color
-$page-header-border-color:    transparent;
+$page-header-border-color:    transparent !default;
 //** Width of horizontal description list titles
-$dl-horizontal-offset:        $component-offset-horizontal;
+$dl-horizontal-offset:        $component-offset-horizontal !default;
 //** Horizontal line color.
-$hr-border:                   $gray-lighter;
+$hr-border:                   $gray-lighter !default;
diff --git a/journal/_variables.scss b/journal/_variables.scss
index ae007b28..216ac653 100644
--- a/journal/_variables.scss
+++ b/journal/_variables.scss
@@ -7,18 +7,18 @@
 //
 //## Gray and brand colors for use across Bootstrap.
 
-$gray-base:              #000;
-$gray-darker:            lighten($gray-base, 13.5%); // #222
-$gray-dark:              lighten($gray-base, 20%);   // #333
-$gray:                   #777; // #555
-$gray-light:             lighten($gray-base, 60%);   // #999
-$gray-lighter:           lighten($gray-base, 93.5%); // #eee
+$gray-base:              #000 !default;
+$gray-darker:            lighten($gray-base, 13.5%) !default; // #222
+$gray-dark:              lighten($gray-base, 20%) !default;   // #333
+$gray:                   #777 !default; // #555
+$gray-light:             lighten($gray-base, 60%) !default;   // #999
+$gray-lighter:           lighten($gray-base, 93.5%) !default; // #eee
 
-$brand-primary:         #EB6864;
-$brand-success:         #22B24C;
-$brand-info:            #369;
-$brand-warning:         #F5E625;
-$brand-danger:          #F57A00;
+$brand-primary:         #EB6864 !default;
+$brand-success:         #22B24C !default;
+$brand-info:            #369 !default;
+$brand-warning:         #F5E625 !default;
+$brand-danger:          #F57A00 !default;
 
 
 //== Scaffolding
@@ -26,49 +26,49 @@ $brand-danger:          #F57A00;
 //## Settings for some of the most global styles.
 
 //** Background color for ``.
-$body-bg:               #fff;
+$body-bg:               #fff !default;
 //** Global text color on ``.
-$text-color:            $gray;
+$text-color:            $gray !default;
 
 //** Global textual link color.
-$link-color:            $brand-primary;
+$link-color:            $brand-primary !default;
 //** Link hover color set via `darken()` function.
-$link-hover-color:      darken($link-color, 15%);
+$link-hover-color:      darken($link-color, 15%) !default;
 //** Link hover decoration.
-$link-hover-decoration: underline;
+$link-hover-decoration: underline !default;
 
 
 //== Typography
 //
 //## Font, line-height, and color for body text, headings, and more.
 
-$font-family-sans-serif:  "News Cycle", "Arial Narrow Bold", sans-serif;
-$font-family-serif:       Georgia, "Times New Roman", Times, serif;
+$font-family-sans-serif:  "News Cycle", "Arial Narrow Bold", sans-serif !default;
+$font-family-serif:       Georgia, "Times New Roman", Times, serif !default;
 //** Default monospace fonts for ``, ``, and `
`.
-$font-family-monospace:   Menlo, Monaco, Consolas, "Courier New", monospace;
-$font-family-base:        $font-family-serif;
+$font-family-monospace:   Menlo, Monaco, Consolas, "Courier New", monospace !default;
+$font-family-base:        $font-family-serif !default;
 
-$font-size-base:          15px;
-$font-size-large:         ceil(($font-size-base * 1.25)); // ~18px
-$font-size-small:         ceil(($font-size-base * 0.85)); // ~12px
+$font-size-base:          15px !default;
+$font-size-large:         ceil(($font-size-base * 1.25)) !default; // ~18px
+$font-size-small:         ceil(($font-size-base * 0.85)) !default; // ~12px
 
-$font-size-h1:            floor(($font-size-base * 2.6)); // ~36px
-$font-size-h2:            floor(($font-size-base * 2.15)); // ~30px
-$font-size-h3:            ceil(($font-size-base * 1.7)); // ~24px
-$font-size-h4:            ceil(($font-size-base * 1.25)); // ~18px
-$font-size-h5:            $font-size-base;
-$font-size-h6:            ceil(($font-size-base * 0.85)); // ~12px
+$font-size-h1:            floor(($font-size-base * 2.6)) !default; // ~36px
+$font-size-h2:            floor(($font-size-base * 2.15)) !default; // ~30px
+$font-size-h3:            ceil(($font-size-base * 1.7)) !default; // ~24px
+$font-size-h4:            ceil(($font-size-base * 1.25)) !default; // ~18px
+$font-size-h5:            $font-size-base !default;
+$font-size-h6:            ceil(($font-size-base * 0.85)) !default; // ~12px
 
 //** Unit-less `line-height` for use in components like buttons.
-$line-height-base:        1.428571429; // 20/14
+$line-height-base:        1.428571429 !default; // 20/14
 //** Computed "line-height" (`font-size` * `line-height`) for use with `margin`, `padding`, etc.
-$line-height-computed:    floor(($font-size-base * $line-height-base)); // ~20px
+$line-height-computed:    floor(($font-size-base * $line-height-base)) !default; // ~20px
 
 //** By default, this inherits from the ``.
-$headings-font-family:    $font-family-sans-serif;
-$headings-font-weight:    700;
-$headings-line-height:    1.1;
-$headings-color:          #000;
+$headings-font-family:    $font-family-sans-serif !default;
+$headings-font-weight:    700 !default;
+$headings-line-height:    1.1 !default;
+$headings-color:          #000 !default;
 
 
 //== Iconography
@@ -76,45 +76,45 @@ $headings-color:          #000;
 //## Specify custom location and filename of the included Glyphicons icon font. Useful for those including Bootstrap via Bower.
 
 //** Load fonts from this directory.
-$icon-font-path:          "../fonts/";
+$icon-font-path:          "../fonts/" !default;
 //** File name for all font files.
-$icon-font-name:          "glyphicons-halflings-regular";
+$icon-font-name:          "glyphicons-halflings-regular" !default;
 //** Element ID within SVG icon file.
-$icon-font-svg-id:        "glyphicons_halflingsregular";
+$icon-font-svg-id:        "glyphicons_halflingsregular" !default;
 
 
 //== Components
 //
 //## Define common padding and border radius sizes and more. Values based on 14px text and 1.428 line-height (~20px to start).
 
-$padding-base-vertical:     8px;
-$padding-base-horizontal:   12px;
+$padding-base-vertical:     8px !default;
+$padding-base-horizontal:   12px !default;
 
-$padding-large-vertical:    14px;
-$padding-large-horizontal:  16px;
+$padding-large-vertical:    14px !default;
+$padding-large-horizontal:  16px !default;
 
-$padding-small-vertical:    5px;
-$padding-small-horizontal:  10px;
+$padding-small-vertical:    5px !default;
+$padding-small-horizontal:  10px !default;
 
-$padding-xs-vertical:       1px;
-$padding-xs-horizontal:     5px;
+$padding-xs-vertical:       1px !default;
+$padding-xs-horizontal:     5px !default;
 
-$line-height-large:         1.3333333; // extra decimals for Win 8.1 Chrome
-$line-height-small:         1.5;
+$line-height-large:         1.3333333 !default; // extra decimals for Win 8.1 Chrome
+$line-height-small:         1.5 !default;
 
-$border-radius-base:        4px;
-$border-radius-large:       6px;
-$border-radius-small:       3px;
+$border-radius-base:        4px !default;
+$border-radius-large:       6px !default;
+$border-radius-small:       3px !default;
 
 //** Global color for active items (e.g., navs or dropdowns).
-$component-active-color:    #fff;
+$component-active-color:    #fff !default;
 //** Global background color for active items (e.g., navs or dropdowns).
-$component-active-bg:       $brand-primary;
+$component-active-bg:       $brand-primary !default;
 
 //** Width of the `border` for generating carets that indicator dropdowns.
-$caret-width-base:          4px;
+$caret-width-base:          4px !default;
 //** Carets increase slightly in size for larger components.
-$caret-width-large:         5px;
+$caret-width-large:         5px !default;
 
 
 //== Tables
@@ -122,53 +122,53 @@ $caret-width-large:         5px;
 //## Customizes the `.table` component with basic values, each used across all table variations.
 
 //** Padding for ``s and ``s.
-$table-cell-padding:            8px;
+$table-cell-padding:            8px !default;
 //** Padding for cells in `.table-condensed`.
-$table-condensed-cell-padding:  5px;
+$table-condensed-cell-padding:  5px !default;
 
 //** Default background color used for all tables.
-$table-bg:                      transparent;
+$table-bg:                      transparent !default;
 //** Background color used for `.table-striped`.
-$table-bg-accent:               #f9f9f9;
+$table-bg-accent:               #f9f9f9 !default;
 //** Background color used for `.table-hover`.
-$table-bg-hover:                #f5f5f5;
-$table-bg-active:               $table-bg-hover;
+$table-bg-hover:                #f5f5f5 !default;
+$table-bg-active:               $table-bg-hover !default;
 
 //** Border color for table and cell borders.
-$table-border-color:            #ddd;
+$table-border-color:            #ddd !default;
 
 
 //== Buttons
 //
 //## For each of Bootstrap's buttons, define text, background and border color.
 
-$btn-font-weight:                normal;
+$btn-font-weight:                normal !default;
 
-$btn-default-color:              #fff;
-$btn-default-bg:                 $gray-light;
-$btn-default-border:             $btn-default-bg;
+$btn-default-color:              #fff !default;
+$btn-default-bg:                 $gray-light !default;
+$btn-default-border:             $btn-default-bg !default;
 
-$btn-primary-color:              $btn-default-color;
-$btn-primary-bg:                 $brand-primary;
-$btn-primary-border:             $btn-primary-bg;
+$btn-primary-color:              $btn-default-color !default;
+$btn-primary-bg:                 $brand-primary !default;
+$btn-primary-border:             $btn-primary-bg !default;
 
-$btn-success-color:              $btn-default-color;
-$btn-success-bg:                 $brand-success;
-$btn-success-border:             $btn-success-bg;
+$btn-success-color:              $btn-default-color !default;
+$btn-success-bg:                 $brand-success !default;
+$btn-success-border:             $btn-success-bg !default;
 
-$btn-info-color:                 $btn-default-color;
-$btn-info-bg:                    $brand-info;
-$btn-info-border:                $btn-info-bg;
+$btn-info-color:                 $btn-default-color !default;
+$btn-info-bg:                    $brand-info !default;
+$btn-info-border:                $btn-info-bg !default;
 
-$btn-warning-color:              $btn-default-color;
-$btn-warning-bg:                 $brand-warning;
-$btn-warning-border:             $btn-warning-bg;
+$btn-warning-color:              $btn-default-color !default;
+$btn-warning-bg:                 $brand-warning !default;
+$btn-warning-border:             $btn-warning-bg !default;
 
-$btn-danger-color:               $btn-default-color;
-$btn-danger-bg:                  $brand-danger;
-$btn-danger-border:              $btn-danger-bg;
+$btn-danger-color:               $btn-default-color !default;
+$btn-danger-bg:                  $brand-danger !default;
+$btn-danger-border:              $btn-danger-bg !default;
 
-$btn-link-disabled-color:        $gray-light;
+$btn-link-disabled-color:        $gray-light !default;
 
 
 //== Forms
@@ -176,50 +176,50 @@ $btn-link-disabled-color:        $gray-light;
 //##
 
 //** `` background color
-$input-bg:                       #fff;
+$input-bg:                       #fff !default;
 //** `` background color
-$input-bg-disabled:              $gray-lighter;
+$input-bg-disabled:              $gray-lighter !default;
 
 //** Text color for ``s
-$input-color:                    $text-color;
+$input-color:                    $text-color !default;
 //** `` border color
-$input-border:                   #ccc;
+$input-border:                   #ccc !default;
 
 // TODO: Rename `$input-border-radius` to `$input-border-radius-base` in v4
 //** Default `.form-control` border radius
 // This has no effect on ``s in CSS.
-$input-border-radius:            $border-radius-base;
+$input-border-radius:            $border-radius-base !default;
 //** Large `.form-control` border radius
-$input-border-radius-large:      $border-radius-large;
+$input-border-radius-large:      $border-radius-large !default;
 //** Small `.form-control` border radius
-$input-border-radius-small:      $border-radius-small;
+$input-border-radius-small:      $border-radius-small !default;
 
 //** Border color for inputs on focus
-$input-border-focus:             #66afe9;
+$input-border-focus:             #66afe9 !default;
 
 //** Placeholder text color
-$input-color-placeholder:        $gray-light;
+$input-color-placeholder:        $gray-light !default;
 
 //** Default `.form-control` height
-$input-height-base:              ($line-height-computed + ($padding-base-vertical * 2) + 2);
+$input-height-base:              ($line-height-computed + ($padding-base-vertical * 2) + 2) !default;
 //** Large `.form-control` height
-$input-height-large:             (ceil($font-size-large * $line-height-large) + ($padding-large-vertical * 2) + 2);
+$input-height-large:             (ceil($font-size-large * $line-height-large) + ($padding-large-vertical * 2) + 2) !default;
 //** Small `.form-control` height
-$input-height-small:             (floor($font-size-small * $line-height-small) + ($padding-small-vertical * 2) + 2);
+$input-height-small:             (floor($font-size-small * $line-height-small) + ($padding-small-vertical * 2) + 2) !default;
 
 //** `.form-group` margin
-$form-group-margin-bottom:       15px;
+$form-group-margin-bottom:       15px !default;
 
-$legend-color:                   $text-color;
-$legend-border-color:            #e5e5e5;
+$legend-color:                   $text-color !default;
+$legend-border-color:            #e5e5e5 !default;
 
 //** Background color for textual input addons
-$input-group-addon-bg:           $gray-lighter;
+$input-group-addon-bg:           $gray-lighter !default;
 //** Border color for textual input addons
-$input-group-addon-border-color: $input-border;
+$input-group-addon-border-color: $input-border !default;
 
 //** Disabled cursor for form controls and buttons.
-$cursor-disabled:                not-allowed;
+$cursor-disabled:                not-allowed !default;
 
 
 //== Dropdowns
@@ -227,34 +227,34 @@ $cursor-disabled:                not-allowed;
 //## Dropdown menu container and contents.
 
 //** Background for the dropdown menu.
-$dropdown-bg:                    #fff;
+$dropdown-bg:                    #fff !default;
 //** Dropdown menu `border-color`.
-$dropdown-border:                rgba(0,0,0,.15);
+$dropdown-border:                rgba(0,0,0,.15) !default;
 //** Dropdown menu `border-color` **for IE8**.
-$dropdown-fallback-border:       #ccc;
+$dropdown-fallback-border:       #ccc !default;
 //** Divider color for between dropdown items.
-$dropdown-divider-bg:            #e5e5e5;
+$dropdown-divider-bg:            #e5e5e5 !default;
 
 //** Dropdown link text color.
-$dropdown-link-color:            $gray-dark;
+$dropdown-link-color:            $gray-dark !default;
 //** Hover color for dropdown links.
-$dropdown-link-hover-color:      #fff;
+$dropdown-link-hover-color:      #fff !default;
 //** Hover background for dropdown links.
-$dropdown-link-hover-bg:         $component-active-bg;
+$dropdown-link-hover-bg:         $component-active-bg !default;
 
 //** Active dropdown menu item text color.
-$dropdown-link-active-color:     #fff;
+$dropdown-link-active-color:     #fff !default;
 //** Active dropdown menu item background color.
-$dropdown-link-active-bg:        $component-active-bg;
+$dropdown-link-active-bg:        $component-active-bg !default;
 
 //** Disabled dropdown menu item background color.
-$dropdown-link-disabled-color:   $gray-light;
+$dropdown-link-disabled-color:   $gray-light !default;
 
 //** Text color for headers within dropdown menus.
-$dropdown-header-color:          $gray-light;
+$dropdown-header-color:          $gray-light !default;
 
 //** Deprecated `$dropdown-caret-color` as of v3.1.0
-$dropdown-caret-color:           #000;
+$dropdown-caret-color:           #000 !default;
 
 
 //-- Z-index master list
@@ -264,13 +264,13 @@ $dropdown-caret-color:           #000;
 //
 // Note: These variables are not generated into the Customizer.
 
-$zindex-navbar:            1000;
-$zindex-dropdown:          1000;
-$zindex-popover:           1060;
-$zindex-tooltip:           1070;
-$zindex-navbar-fixed:      1030;
-$zindex-modal-background:  1040;
-$zindex-modal:             1050;
+$zindex-navbar:            1000 !default;
+$zindex-dropdown:          1000 !default;
+$zindex-popover:           1060 !default;
+$zindex-tooltip:           1070 !default;
+$zindex-navbar-fixed:      1030 !default;
+$zindex-modal-background:  1040 !default;
+$zindex-modal:             1050 !default;
 
 
 //== Media queries breakpoints
@@ -279,37 +279,37 @@ $zindex-modal:             1050;
 
 // Extra small screen / phone
 //** Deprecated `$screen-xs` as of v3.0.1
-$screen-xs:                  480px;
+$screen-xs:                  480px !default;
 //** Deprecated `$screen-xs-min` as of v3.2.0
-$screen-xs-min:              $screen-xs;
+$screen-xs-min:              $screen-xs !default;
 //** Deprecated `$screen-phone` as of v3.0.1
-$screen-phone:               $screen-xs-min;
+$screen-phone:               $screen-xs-min !default;
 
 // Small screen / tablet
 //** Deprecated `$screen-sm` as of v3.0.1
-$screen-sm:                  768px;
-$screen-sm-min:              $screen-sm;
+$screen-sm:                  768px !default;
+$screen-sm-min:              $screen-sm !default;
 //** Deprecated `$screen-tablet` as of v3.0.1
-$screen-tablet:              $screen-sm-min;
+$screen-tablet:              $screen-sm-min !default;
 
 // Medium screen / desktop
 //** Deprecated `$screen-md` as of v3.0.1
-$screen-md:                  992px;
-$screen-md-min:              $screen-md;
+$screen-md:                  992px !default;
+$screen-md-min:              $screen-md !default;
 //** Deprecated `$screen-desktop` as of v3.0.1
-$screen-desktop:             $screen-md-min;
+$screen-desktop:             $screen-md-min !default;
 
 // Large screen / wide desktop
 //** Deprecated `$screen-lg` as of v3.0.1
-$screen-lg:                  1200px;
-$screen-lg-min:              $screen-lg;
+$screen-lg:                  1200px !default;
+$screen-lg-min:              $screen-lg !default;
 //** Deprecated `$screen-lg-desktop` as of v3.0.1
-$screen-lg-desktop:          $screen-lg-min;
+$screen-lg-desktop:          $screen-lg-min !default;
 
 // So media queries don't overlap when required, provide a maximum
-$screen-xs-max:              ($screen-sm-min - 1);
-$screen-sm-max:              ($screen-md-min - 1);
-$screen-md-max:              ($screen-lg-min - 1);
+$screen-xs-max:              ($screen-sm-min - 1) !default;
+$screen-sm-max:              ($screen-md-min - 1) !default;
+$screen-md-max:              ($screen-lg-min - 1) !default;
 
 
 //== Grid system
@@ -317,14 +317,14 @@ $screen-md-max:              ($screen-lg-min - 1);
 //## Define your custom responsive grid.
 
 //** Number of columns in the grid.
-$grid-columns:              12;
+$grid-columns:              12 !default;
 //** Padding between columns. Gets divided in half for the left and right.
-$grid-gutter-width:         30px;
+$grid-gutter-width:         30px !default;
 // Navbar collapse
 //** Point at which the navbar becomes uncollapsed.
-$grid-float-breakpoint:     $screen-sm-min;
+$grid-float-breakpoint:     $screen-sm-min !default;
 //** Point at which the navbar begins collapsing.
-$grid-float-breakpoint-max: ($grid-float-breakpoint - 1);
+$grid-float-breakpoint-max: ($grid-float-breakpoint - 1) !default;
 
 
 //== Container sizes
@@ -332,19 +332,19 @@ $grid-float-breakpoint-max: ($grid-float-breakpoint - 1);
 //## Define the maximum width of `.container` for different screen sizes.
 
 // Small screen / tablet
-$container-tablet:             (720px + $grid-gutter-width);
+$container-tablet:             (720px + $grid-gutter-width) !default;
 //** For `$screen-sm-min` and up.
-$container-sm:                 $container-tablet;
+$container-sm:                 $container-tablet !default;
 
 // Medium screen / desktop
-$container-desktop:            (940px + $grid-gutter-width);
+$container-desktop:            (940px + $grid-gutter-width) !default;
 //** For `$screen-md-min` and up.
-$container-md:                 $container-desktop;
+$container-md:                 $container-desktop !default;
 
 // Large screen / wide desktop
-$container-large-desktop:      (1140px + $grid-gutter-width);
+$container-large-desktop:      (1140px + $grid-gutter-width) !default;
 //** For `$screen-lg-min` and up.
-$container-lg:                 $container-large-desktop;
+$container-lg:                 $container-large-desktop !default;
 
 
 //== Navbar
@@ -352,61 +352,61 @@ $container-lg:                 $container-large-desktop;
 //##
 
 // Basics of a navbar
-$navbar-height:                    60px;
-$navbar-margin-bottom:             $line-height-computed;
-$navbar-border-radius:             $border-radius-base;
-$navbar-padding-horizontal:        floor(($grid-gutter-width / 2));
-$navbar-padding-vertical:          (($navbar-height - $line-height-computed) / 2);
-$navbar-collapse-max-height:       340px;
+$navbar-height:                    60px !default;
+$navbar-margin-bottom:             $line-height-computed !default;
+$navbar-border-radius:             $border-radius-base !default;
+$navbar-padding-horizontal:        floor(($grid-gutter-width / 2)) !default;
+$navbar-padding-vertical:          (($navbar-height - $line-height-computed) / 2) !default;
+$navbar-collapse-max-height:       340px !default;
 
-$navbar-default-color:             #000;
-$navbar-default-bg:                #fff;
-$navbar-default-border:            darken($navbar-default-bg, 6.5%);
+$navbar-default-color:             #000 !default;
+$navbar-default-bg:                #fff !default;
+$navbar-default-border:            darken($navbar-default-bg, 6.5%) !default;
 
 // Navbar links
-$navbar-default-link-color:                #000;
-$navbar-default-link-hover-color:          #000;
-$navbar-default-link-hover-bg:             darken($navbar-default-bg, 6.5%);
-$navbar-default-link-active-color:         #000;
-$navbar-default-link-active-bg:            darken($navbar-default-bg, 6.5%);
-$navbar-default-link-disabled-color:       #ccc;
-$navbar-default-link-disabled-bg:          transparent;
+$navbar-default-link-color:                #000 !default;
+$navbar-default-link-hover-color:          #000 !default;
+$navbar-default-link-hover-bg:             darken($navbar-default-bg, 6.5%) !default;
+$navbar-default-link-active-color:         #000 !default;
+$navbar-default-link-active-bg:            darken($navbar-default-bg, 6.5%) !default;
+$navbar-default-link-disabled-color:       #ccc !default;
+$navbar-default-link-disabled-bg:          transparent !default;
 
 // Navbar brand label
-$navbar-default-brand-color:               $navbar-default-link-color;
-$navbar-default-brand-hover-color:         $navbar-default-link-hover-color;
-$navbar-default-brand-hover-bg:            darken($navbar-default-bg, 6.5%);
+$navbar-default-brand-color:               $navbar-default-link-color !default;
+$navbar-default-brand-hover-color:         $navbar-default-link-hover-color !default;
+$navbar-default-brand-hover-bg:            darken($navbar-default-bg, 6.5%) !default;
 
 // Navbar toggle
-$navbar-default-toggle-hover-bg:           #ddd;
-$navbar-default-toggle-icon-bar-bg:        #ccc;
-$navbar-default-toggle-border-color:       #ddd;
+$navbar-default-toggle-hover-bg:           #ddd !default;
+$navbar-default-toggle-icon-bar-bg:        #ccc !default;
+$navbar-default-toggle-border-color:       #ddd !default;
 
 
 // Inverted navbar
 // Reset inverted navbar basics
-$navbar-inverse-color:                      #fff;
-$navbar-inverse-bg:                         $brand-primary;
-$navbar-inverse-border:                     darken($navbar-inverse-bg, 10%);
+$navbar-inverse-color:                      #fff !default;
+$navbar-inverse-bg:                         $brand-primary !default;
+$navbar-inverse-border:                     darken($navbar-inverse-bg, 10%) !default;
 
 // Inverted navbar links
-$navbar-inverse-link-color:                 #fff;
-$navbar-inverse-link-hover-color:           #fff;
-$navbar-inverse-link-hover-bg:              darken($navbar-inverse-bg, 6.5%);
-$navbar-inverse-link-active-color:          #fff;
-$navbar-inverse-link-active-bg:             darken($navbar-inverse-bg, 6.5%);
-$navbar-inverse-link-disabled-color:        #444;
-$navbar-inverse-link-disabled-bg:           transparent;
+$navbar-inverse-link-color:                 #fff !default;
+$navbar-inverse-link-hover-color:           #fff !default;
+$navbar-inverse-link-hover-bg:              darken($navbar-inverse-bg, 6.5%) !default;
+$navbar-inverse-link-active-color:          #fff !default;
+$navbar-inverse-link-active-bg:             darken($navbar-inverse-bg, 6.5%) !default;
+$navbar-inverse-link-disabled-color:        #444 !default;
+$navbar-inverse-link-disabled-bg:           transparent !default;
 
 // Inverted navbar brand label
-$navbar-inverse-brand-color:                $navbar-inverse-link-color;
-$navbar-inverse-brand-hover-color:          #fff;
-$navbar-inverse-brand-hover-bg:             darken($navbar-inverse-bg, 6.5%);
+$navbar-inverse-brand-color:                $navbar-inverse-link-color !default;
+$navbar-inverse-brand-hover-color:          #fff !default;
+$navbar-inverse-brand-hover-bg:             darken($navbar-inverse-bg, 6.5%) !default;
 
 // Inverted navbar toggle
-$navbar-inverse-toggle-hover-bg:            darken($navbar-inverse-bg, 10%);
-$navbar-inverse-toggle-icon-bar-bg:         #fff;
-$navbar-inverse-toggle-border-color:        darken($navbar-inverse-bg, 10%);
+$navbar-inverse-toggle-hover-bg:            darken($navbar-inverse-bg, 10%) !default;
+$navbar-inverse-toggle-icon-bar-bg:         #fff !default;
+$navbar-inverse-toggle-border-color:        darken($navbar-inverse-bg, 10%) !default;
 
 
 //== Navs
@@ -414,97 +414,97 @@ $navbar-inverse-toggle-border-color:        darken($navbar-inverse-bg, 10%);
 //##
 
 //=== Shared nav styles
-$nav-link-padding:                          10px 15px;
-$nav-link-hover-bg:                         $gray-lighter;
+$nav-link-padding:                          10px 15px !default;
+$nav-link-hover-bg:                         $gray-lighter !default;
 
-$nav-disabled-link-color:                   $gray-light;
-$nav-disabled-link-hover-color:             $gray-light;
+$nav-disabled-link-color:                   $gray-light !default;
+$nav-disabled-link-hover-color:             $gray-light !default;
 
 //== Tabs
-$nav-tabs-border-color:                     #ddd;
+$nav-tabs-border-color:                     #ddd !default;
 
-$nav-tabs-link-hover-border-color:          $gray-lighter;
+$nav-tabs-link-hover-border-color:          $gray-lighter !default;
 
-$nav-tabs-active-link-hover-bg:             $body-bg;
-$nav-tabs-active-link-hover-color:          $gray;
-$nav-tabs-active-link-hover-border-color:   #ddd;
+$nav-tabs-active-link-hover-bg:             $body-bg !default;
+$nav-tabs-active-link-hover-color:          $gray !default;
+$nav-tabs-active-link-hover-border-color:   #ddd !default;
 
-$nav-tabs-justified-link-border-color:            #ddd;
-$nav-tabs-justified-active-link-border-color:     $body-bg;
+$nav-tabs-justified-link-border-color:            #ddd !default;
+$nav-tabs-justified-active-link-border-color:     $body-bg !default;
 
 //== Pills
-$nav-pills-border-radius:                   $border-radius-base;
-$nav-pills-active-link-hover-bg:            $component-active-bg;
-$nav-pills-active-link-hover-color:         $component-active-color;
+$nav-pills-border-radius:                   $border-radius-base !default;
+$nav-pills-active-link-hover-bg:            $component-active-bg !default;
+$nav-pills-active-link-hover-color:         $component-active-color !default;
 
 
 //== Pagination
 //
 //##
 
-$pagination-color:                     $link-color;
-$pagination-bg:                        #fff;
-$pagination-border:                    #ddd;
+$pagination-color:                     $link-color !default;
+$pagination-bg:                        #fff !default;
+$pagination-border:                    #ddd !default;
 
-$pagination-hover-color:               $link-hover-color;
-$pagination-hover-bg:                  $gray-lighter;
-$pagination-hover-border:              #ddd;
+$pagination-hover-color:               $link-hover-color !default;
+$pagination-hover-bg:                  $gray-lighter !default;
+$pagination-hover-border:              #ddd !default;
 
-$pagination-active-color:              $gray-light;
-$pagination-active-bg:                 #f5f5f5;
-$pagination-active-border:             #ddd;
+$pagination-active-color:              $gray-light !default;
+$pagination-active-bg:                 #f5f5f5 !default;
+$pagination-active-border:             #ddd !default;
 
-$pagination-disabled-color:            $gray-light;
-$pagination-disabled-bg:               #fff;
-$pagination-disabled-border:           #ddd;
+$pagination-disabled-color:            $gray-light !default;
+$pagination-disabled-bg:               #fff !default;
+$pagination-disabled-border:           #ddd !default;
 
 
 //== Pager
 //
 //##
 
-$pager-bg:                             $pagination-bg;
-$pager-border:                         $pagination-border;
-$pager-border-radius:                  15px;
+$pager-bg:                             $pagination-bg !default;
+$pager-border:                         $pagination-border !default;
+$pager-border-radius:                  15px !default;
 
-$pager-hover-bg:                       $pagination-hover-bg;
+$pager-hover-bg:                       $pagination-hover-bg !default;
 
-$pager-active-bg:                      $pagination-active-bg;
-$pager-active-color:                   $pagination-active-color;
+$pager-active-bg:                      $pagination-active-bg !default;
+$pager-active-color:                   $pagination-active-color !default;
 
-$pager-disabled-color:                 $gray-light;
+$pager-disabled-color:                 $gray-light !default;
 
 
 //== Jumbotron
 //
 //##
 
-$jumbotron-padding:              30px;
-$jumbotron-color:                inherit;
-$jumbotron-bg:                   $gray-lighter;
-$jumbotron-heading-color:        inherit;
-$jumbotron-font-size:            ceil(($font-size-base * 1.5));
+$jumbotron-padding:              30px !default;
+$jumbotron-color:                inherit !default;
+$jumbotron-bg:                   $gray-lighter !default;
+$jumbotron-heading-color:        inherit !default;
+$jumbotron-font-size:            ceil(($font-size-base * 1.5)) !default;
 
 
 //== Form states and alerts
 //
 //## Define colors for form feedback states and, by default, alerts.
 
-$state-success-text:             #468847;
-$state-success-bg:               #dff0d8;
-$state-success-border:           darken(adjust-hue($state-success-bg, -10), 5%);
+$state-success-text:             #468847 !default;
+$state-success-bg:               #dff0d8 !default;
+$state-success-border:           darken(adjust-hue($state-success-bg, -10), 5%) !default;
 
-$state-info-text:                #3a87ad;
-$state-info-bg:                  #d9edf7;
-$state-info-border:              darken(adjust-hue($state-info-bg, -10), 7%);
+$state-info-text:                #3a87ad !default;
+$state-info-bg:                  #d9edf7 !default;
+$state-info-border:              darken(adjust-hue($state-info-bg, -10), 7%) !default;
 
-$state-warning-text:             #c09853;
-$state-warning-bg:               #fcf8e3;
-$state-warning-border:           darken(adjust-hue($state-warning-bg, -10), 3%);
+$state-warning-text:             #c09853 !default;
+$state-warning-bg:               #fcf8e3 !default;
+$state-warning-border:           darken(adjust-hue($state-warning-bg, -10), 3%) !default;
 
-$state-danger-text:              #b94a48;
-$state-danger-bg:                #f2dede;
-$state-danger-border:            darken(adjust-hue($state-danger-bg, -10), 3%);
+$state-danger-text:              #b94a48 !default;
+$state-danger-bg:                #f2dede !default;
+$state-danger-border:            darken(adjust-hue($state-danger-bg, -10), 3%) !default;
 
 
 //== Tooltips
@@ -512,17 +512,17 @@ $state-danger-border:            darken(adjust-hue($state-danger-bg, -10), 3%);
 //##
 
 //** Tooltip max width
-$tooltip-max-width:           200px;
+$tooltip-max-width:           200px !default;
 //** Tooltip text color
-$tooltip-color:               #fff;
+$tooltip-color:               #fff !default;
 //** Tooltip background color
-$tooltip-bg:                  #000;
-$tooltip-opacity:             .9;
+$tooltip-bg:                  #000 !default;
+$tooltip-opacity:             .9 !default;
 
 //** Tooltip arrow width
-$tooltip-arrow-width:         5px;
+$tooltip-arrow-width:         5px !default;
 //** Tooltip arrow color
-$tooltip-arrow-color:         $tooltip-bg;
+$tooltip-arrow-color:         $tooltip-bg !default;
 
 
 //== Popovers
@@ -530,28 +530,28 @@ $tooltip-arrow-color:         $tooltip-bg;
 //##
 
 //** Popover body background color
-$popover-bg:                          #fff;
+$popover-bg:                          #fff !default;
 //** Popover maximum width
-$popover-max-width:                   276px;
+$popover-max-width:                   276px !default;
 //** Popover border color
-$popover-border-color:                rgba(0,0,0,.2);
+$popover-border-color:                rgba(0,0,0,.2) !default;
 //** Popover fallback border color
-$popover-fallback-border-color:       #ccc;
+$popover-fallback-border-color:       #ccc !default;
 
 //** Popover title background color
-$popover-title-bg:                    darken($popover-bg, 3%);
+$popover-title-bg:                    darken($popover-bg, 3%) !default;
 
 //** Popover arrow width
-$popover-arrow-width:                 10px;
+$popover-arrow-width:                 10px !default;
 //** Popover arrow color
-$popover-arrow-color:                 $popover-bg;
+$popover-arrow-color:                 $popover-bg !default;
 
 //** Popover outer arrow width
-$popover-arrow-outer-width:           ($popover-arrow-width + 1);
+$popover-arrow-outer-width:           ($popover-arrow-width + 1) !default;
 //** Popover outer arrow color
-$popover-arrow-outer-color:           fadein($popover-border-color, 5%);
+$popover-arrow-outer-color:           fadein($popover-border-color, 5%) !default;
 //** Popover outer arrow fallback color
-$popover-arrow-outer-fallback-color:  darken($popover-fallback-border-color, 20%);
+$popover-arrow-outer-fallback-color:  darken($popover-fallback-border-color, 20%) !default;
 
 
 //== Labels
@@ -559,22 +559,22 @@ $popover-arrow-outer-fallback-color:  darken($popover-fallback-border-color, 20%
 //##
 
 //** Default label background color
-$label-default-bg:            $btn-default-bg;
+$label-default-bg:            $btn-default-bg !default;
 //** Primary label background color
-$label-primary-bg:            $brand-primary;
+$label-primary-bg:            $brand-primary !default;
 //** Success label background color
-$label-success-bg:            $brand-success;
+$label-success-bg:            $brand-success !default;
 //** Info label background color
-$label-info-bg:               $brand-info;
+$label-info-bg:               $brand-info !default;
 //** Warning label background color
-$label-warning-bg:            $brand-warning;
+$label-warning-bg:            $brand-warning !default;
 //** Danger label background color
-$label-danger-bg:             $brand-danger;
+$label-danger-bg:             $brand-danger !default;
 
 //** Default label text color
-$label-color:                 #fff;
+$label-color:                 #fff !default;
 //** Default text color of a linked label
-$label-link-hover-color:      #fff;
+$label-link-hover-color:      #fff !default;
 
 
 //== Modals
@@ -582,57 +582,57 @@ $label-link-hover-color:      #fff;
 //##
 
 //** Padding applied to the modal body
-$modal-inner-padding:         20px;
+$modal-inner-padding:         20px !default;
 
 //** Padding applied to the modal title
-$modal-title-padding:         15px;
+$modal-title-padding:         15px !default;
 //** Modal title line-height
-$modal-title-line-height:     $line-height-base;
+$modal-title-line-height:     $line-height-base !default;
 
 //** Background color of modal content area
-$modal-content-bg:                             #fff;
+$modal-content-bg:                             #fff !default;
 //** Modal content border color
-$modal-content-border-color:                   rgba(0,0,0,.2);
+$modal-content-border-color:                   rgba(0,0,0,.2) !default;
 //** Modal content border color **for IE8**
-$modal-content-fallback-border-color:          #999;
+$modal-content-fallback-border-color:          #999 !default;
 
 //** Modal backdrop background color
-$modal-backdrop-bg:           #000;
+$modal-backdrop-bg:           #000 !default;
 //** Modal backdrop opacity
-$modal-backdrop-opacity:      .5;
+$modal-backdrop-opacity:      .5 !default;
 //** Modal header border color
-$modal-header-border-color:   #e5e5e5;
+$modal-header-border-color:   #e5e5e5 !default;
 //** Modal footer border color
-$modal-footer-border-color:   $modal-header-border-color;
+$modal-footer-border-color:   $modal-header-border-color !default;
 
-$modal-lg:                    900px;
-$modal-md:                    600px;
-$modal-sm:                    300px;
+$modal-lg:                    900px !default;
+$modal-md:                    600px !default;
+$modal-sm:                    300px !default;
 
 
 //== Alerts
 //
 //## Define alert colors, border radius, and padding.
 
-$alert-padding:               15px;
-$alert-border-radius:         $border-radius-base;
-$alert-link-font-weight:      bold;
+$alert-padding:               15px !default;
+$alert-border-radius:         $border-radius-base !default;
+$alert-link-font-weight:      bold !default;
 
-$alert-success-bg:            $state-success-bg;
-$alert-success-text:          $state-success-text;
-$alert-success-border:        $state-success-border;
+$alert-success-bg:            $state-success-bg !default;
+$alert-success-text:          $state-success-text !default;
+$alert-success-border:        $state-success-border !default;
 
-$alert-info-bg:               $state-info-bg;
-$alert-info-text:             $state-info-text;
-$alert-info-border:           $state-info-border;
+$alert-info-bg:               $state-info-bg !default;
+$alert-info-text:             $state-info-text !default;
+$alert-info-border:           $state-info-border !default;
 
-$alert-warning-bg:            $state-warning-bg;
-$alert-warning-text:          $state-warning-text;
-$alert-warning-border:        $state-warning-border;
+$alert-warning-bg:            $state-warning-bg !default;
+$alert-warning-text:          $state-warning-text !default;
+$alert-warning-border:        $state-warning-border !default;
 
-$alert-danger-bg:             $state-danger-bg;
-$alert-danger-text:           $state-danger-text;
-$alert-danger-border:         $state-danger-border;
+$alert-danger-bg:             $state-danger-bg !default;
+$alert-danger-text:           $state-danger-text !default;
+$alert-danger-border:         $state-danger-border !default;
 
 
 //== Progress bars
@@ -640,22 +640,22 @@ $alert-danger-border:         $state-danger-border;
 //##
 
 //** Background color of the whole progress component
-$progress-bg:                 #f5f5f5;
+$progress-bg:                 #f5f5f5 !default;
 //** Progress bar text color
-$progress-bar-color:          #fff;
+$progress-bar-color:          #fff !default;
 //** Variable for setting rounded corners on progress bar.
-$progress-border-radius:      $border-radius-base;
+$progress-border-radius:      $border-radius-base !default;
 
 //** Default progress bar color
-$progress-bar-bg:             $brand-primary;
+$progress-bar-bg:             $brand-primary !default;
 //** Success progress bar color
-$progress-bar-success-bg:     $brand-success;
+$progress-bar-success-bg:     $brand-success !default;
 //** Warning progress bar color
-$progress-bar-warning-bg:     $brand-warning;
+$progress-bar-warning-bg:     $brand-warning !default;
 //** Danger progress bar color
-$progress-bar-danger-bg:      $brand-danger;
+$progress-bar-danger-bg:      $brand-danger !default;
 //** Info progress bar color
-$progress-bar-info-bg:        $brand-info;
+$progress-bar-info-bg:        $brand-info !default;
 
 
 //== List group
@@ -663,72 +663,72 @@ $progress-bar-info-bg:        $brand-info;
 //##
 
 //** Background color on `.list-group-item`
-$list-group-bg:                 #fff;
+$list-group-bg:                 #fff !default;
 //** `.list-group-item` border color
-$list-group-border:             #ddd;
+$list-group-border:             #ddd !default;
 //** List group border radius
-$list-group-border-radius:      $border-radius-base;
+$list-group-border-radius:      $border-radius-base !default;
 
 //** Background color of single list items on hover
-$list-group-hover-bg:           #f5f5f5;
+$list-group-hover-bg:           #f5f5f5 !default;
 //** Text color of active list items
-$list-group-active-color:       $component-active-color;
+$list-group-active-color:       $component-active-color !default;
 //** Background color of active list items
-$list-group-active-bg:          $component-active-bg;
+$list-group-active-bg:          $component-active-bg !default;
 //** Border color of active list elements
-$list-group-active-border:      $list-group-active-bg;
+$list-group-active-border:      $list-group-active-bg !default;
 //** Text color for content within active list items
-$list-group-active-text-color:  lighten($list-group-active-bg, 40%);
+$list-group-active-text-color:  lighten($list-group-active-bg, 40%) !default;
 
 //** Text color of disabled list items
-$list-group-disabled-color:      $gray-light;
+$list-group-disabled-color:      $gray-light !default;
 //** Background color of disabled list items
-$list-group-disabled-bg:         $gray-lighter;
+$list-group-disabled-bg:         $gray-lighter !default;
 //** Text color for content within disabled list items
-$list-group-disabled-text-color: $list-group-disabled-color;
+$list-group-disabled-text-color: $list-group-disabled-color !default;
 
-$list-group-link-color:         #555;
-$list-group-link-hover-color:   $list-group-link-color;
-$list-group-link-heading-color: #333;
+$list-group-link-color:         #555 !default;
+$list-group-link-hover-color:   $list-group-link-color !default;
+$list-group-link-heading-color: #333 !default;
 
 
 //== Panels
 //
 //##
 
-$panel-bg:                    #fff;
-$panel-body-padding:          15px;
-$panel-heading-padding:       10px 15px;
-$panel-footer-padding:        $panel-heading-padding;
-$panel-border-radius:         $border-radius-base;
+$panel-bg:                    #fff !default;
+$panel-body-padding:          15px !default;
+$panel-heading-padding:       10px 15px !default;
+$panel-footer-padding:        $panel-heading-padding !default;
+$panel-border-radius:         $border-radius-base !default;
 
 //** Border color for elements within panels
-$panel-inner-border:          #ddd;
-$panel-footer-bg:             #f5f5f5;
+$panel-inner-border:          #ddd !default;
+$panel-footer-bg:             #f5f5f5 !default;
 
-$panel-default-text:          $text-color;
-$panel-default-border:        #ddd;
-$panel-default-heading-bg:    #f5f5f5;
+$panel-default-text:          $text-color !default;
+$panel-default-border:        #ddd !default;
+$panel-default-heading-bg:    #f5f5f5 !default;
 
-$panel-primary-text:          #fff;
-$panel-primary-border:        $brand-primary;
-$panel-primary-heading-bg:    $brand-primary;
+$panel-primary-text:          #fff !default;
+$panel-primary-border:        $brand-primary !default;
+$panel-primary-heading-bg:    $brand-primary !default;
 
-$panel-success-text:          $state-success-text;
-$panel-success-border:        $brand-success;
-$panel-success-heading-bg:    $brand-success;
+$panel-success-text:          $state-success-text !default;
+$panel-success-border:        $brand-success !default;
+$panel-success-heading-bg:    $brand-success !default;
 
-$panel-info-text:             $state-info-text;
-$panel-info-border:           $brand-info;
-$panel-info-heading-bg:       $brand-info;
+$panel-info-text:             $state-info-text !default;
+$panel-info-border:           $brand-info !default;
+$panel-info-heading-bg:       $brand-info !default;
 
-$panel-warning-text:          $state-warning-text;
-$panel-warning-border:        $brand-warning;
-$panel-warning-heading-bg:    $brand-warning;
+$panel-warning-text:          $state-warning-text !default;
+$panel-warning-border:        $brand-warning !default;
+$panel-warning-heading-bg:    $brand-warning !default;
 
-$panel-danger-text:           $state-danger-text;
-$panel-danger-border:         $brand-danger;
-$panel-danger-heading-bg:     $brand-danger;
+$panel-danger-text:           $state-danger-text !default;
+$panel-danger-border:         $brand-danger !default;
+$panel-danger-heading-bg:     $brand-danger !default;
 
 
 //== Thumbnails
@@ -736,103 +736,103 @@ $panel-danger-heading-bg:     $brand-danger;
 //##
 
 //** Padding around the thumbnail image
-$thumbnail-padding:           4px;
+$thumbnail-padding:           4px !default;
 //** Thumbnail background color
-$thumbnail-bg:                $body-bg;
+$thumbnail-bg:                $body-bg !default;
 //** Thumbnail border color
-$thumbnail-border:            #ddd;
+$thumbnail-border:            #ddd !default;
 //** Thumbnail border radius
-$thumbnail-border-radius:     $border-radius-base;
+$thumbnail-border-radius:     $border-radius-base !default;
 
 //** Custom text color for thumbnail captions
-$thumbnail-caption-color:     $text-color;
+$thumbnail-caption-color:     $text-color !default;
 //** Padding around the thumbnail caption
-$thumbnail-caption-padding:   9px;
+$thumbnail-caption-padding:   9px !default;
 
 
 //== Wells
 //
 //##
 
-$well-bg:                     #f5f5f5;
-$well-border:                 darken($well-bg, 7%);
+$well-bg:                     #f5f5f5 !default;
+$well-border:                 darken($well-bg, 7%) !default;
 
 
 //== Badges
 //
 //##
 
-$badge-color:                 #fff;
+$badge-color:                 #fff !default;
 //** Linked badge text color on hover
-$badge-link-hover-color:      #fff;
-$badge-bg:                    $link-color;
+$badge-link-hover-color:      #fff !default;
+$badge-bg:                    $link-color !default;
 
 //** Badge text color in active nav link
-$badge-active-color:          $link-color;
+$badge-active-color:          $link-color !default;
 //** Badge background color in active nav link
-$badge-active-bg:             #fff;
+$badge-active-bg:             #fff !default;
 
-$badge-font-weight:           bold;
-$badge-line-height:           1;
-$badge-border-radius:         10px;
+$badge-font-weight:           bold !default;
+$badge-line-height:           1 !default;
+$badge-border-radius:         10px !default;
 
 
 //== Breadcrumbs
 //
 //##
 
-$breadcrumb-padding-vertical:   8px;
-$breadcrumb-padding-horizontal: 15px;
+$breadcrumb-padding-vertical:   8px !default;
+$breadcrumb-padding-horizontal: 15px !default;
 //** Breadcrumb background color
-$breadcrumb-bg:                 #f5f5f5;
+$breadcrumb-bg:                 #f5f5f5 !default;
 //** Breadcrumb text color
-$breadcrumb-color:              #ccc;
+$breadcrumb-color:              #ccc !default;
 //** Text color of current page in the breadcrumb
-$breadcrumb-active-color:       $gray-light;
+$breadcrumb-active-color:       $gray-light !default;
 //** Textual separator for between breadcrumb elements
-$breadcrumb-separator:          "/";
+$breadcrumb-separator:          "/" !default;
 
 
 //== Carousel
 //
 //##
 
-$carousel-text-shadow:                        0 1px 2px rgba(0,0,0,.6);
+$carousel-text-shadow:                        0 1px 2px rgba(0,0,0,.6) !default;
 
-$carousel-control-color:                      #fff;
-$carousel-control-width:                      15%;
-$carousel-control-opacity:                    .5;
-$carousel-control-font-size:                  20px;
+$carousel-control-color:                      #fff !default;
+$carousel-control-width:                      15% !default;
+$carousel-control-opacity:                    .5 !default;
+$carousel-control-font-size:                  20px !default;
 
-$carousel-indicator-active-bg:                #fff;
-$carousel-indicator-border-color:             #fff;
+$carousel-indicator-active-bg:                #fff !default;
+$carousel-indicator-border-color:             #fff !default;
 
-$carousel-caption-color:                      #fff;
+$carousel-caption-color:                      #fff !default;
 
 
 //== Close
 //
 //##
 
-$close-font-weight:           bold;
-$close-color:                 #000;
-$close-text-shadow:           0 1px 0 #fff;
+$close-font-weight:           bold !default;
+$close-color:                 #000 !default;
+$close-text-shadow:           0 1px 0 #fff !default;
 
 
 //== Code
 //
 //##
 
-$code-color:                  #c7254e;
-$code-bg:                     #f9f2f4;
+$code-color:                  #c7254e !default;
+$code-bg:                     #f9f2f4 !default;
 
-$kbd-color:                   #fff;
-$kbd-bg:                      #333;
+$kbd-color:                   #fff !default;
+$kbd-bg:                      #333 !default;
 
-$pre-bg:                      #f5f5f5;
-$pre-color:                   $gray-dark;
-$pre-border-color:            #ccc;
-$pre-scrollable-max-height:   340px;
+$pre-bg:                      #f5f5f5 !default;
+$pre-color:                   $gray-dark !default;
+$pre-border-color:            #ccc !default;
+$pre-scrollable-max-height:   340px !default;
 
 
 //== Type
@@ -840,22 +840,22 @@ $pre-scrollable-max-height:   340px;
 //##
 
 //** Horizontal offset for forms and lists.
-$component-offset-horizontal: 180px;
+$component-offset-horizontal: 180px !default;
 //** Text muted color
-$text-muted:                  $gray-light;
+$text-muted:                  $gray-light !default;
 //** Abbreviations and acronyms border color
-$abbr-border-color:           $gray-light;
+$abbr-border-color:           $gray-light !default;
 //** Headings small color
-$headings-small-color:        $gray-light;
+$headings-small-color:        $gray-light !default;
 //** Blockquote small color
-$blockquote-small-color:      $gray-light;
+$blockquote-small-color:      $gray-light !default;
 //** Blockquote font size
-$blockquote-font-size:        ($font-size-base * 1.25);
+$blockquote-font-size:        ($font-size-base * 1.25) !default;
 //** Blockquote border color
-$blockquote-border-color:     $gray-lighter;
+$blockquote-border-color:     $gray-lighter !default;
 //** Page header border color
-$page-header-border-color:    $gray-lighter;
+$page-header-border-color:    $gray-lighter !default;
 //** Width of horizontal description list titles
-$dl-horizontal-offset:        $component-offset-horizontal;
+$dl-horizontal-offset:        $component-offset-horizontal !default;
 //** Horizontal line color.
-$hr-border:                   $gray-lighter;
+$hr-border:                   $gray-lighter !default;
diff --git a/lumen/_variables.scss b/lumen/_variables.scss
index dc81f4f1..b9ee16d2 100644
--- a/lumen/_variables.scss
+++ b/lumen/_variables.scss
@@ -7,18 +7,18 @@
 //
 //## Gray and brand colors for use across Bootstrap.
 
-$gray-base:              #000;
-$gray-darker:            lighten($gray-base, 13.5%); // #222
-$gray-dark:              lighten($gray-base, 20%);   // #333
-$gray:                   lighten($gray-base, 33.5%); // #555
-$gray-light:             lighten($gray-base, 60%);   // #999
-$gray-lighter:           lighten($gray-base, 93.5%); // #eee
+$gray-base:              #000 !default;
+$gray-darker:            lighten($gray-base, 13.5%) !default; // #222
+$gray-dark:              lighten($gray-base, 20%) !default;   // #333
+$gray:                   lighten($gray-base, 33.5%) !default; // #555
+$gray-light:             lighten($gray-base, 60%) !default;   // #999
+$gray-lighter:           lighten($gray-base, 93.5%) !default; // #eee
 
-$brand-primary:         #158CBA;
-$brand-success:         #28B62C;
-$brand-info:            #75CAEB;
-$brand-warning:         #FF851B;
-$brand-danger:          #FF4136;
+$brand-primary:         #158CBA !default;
+$brand-success:         #28B62C !default;
+$brand-info:            #75CAEB !default;
+$brand-warning:         #FF851B !default;
+$brand-danger:          #FF4136 !default;
 
 
 //== Scaffolding
@@ -26,49 +26,49 @@ $brand-danger:          #FF4136;
 //## Settings for some of the most global styles.
 
 //** Background color for ``.
-$body-bg:               #fff;
+$body-bg:               #fff !default;
 //** Global text color on ``.
-$text-color:            $gray;
+$text-color:            $gray !default;
 
 //** Global textual link color.
-$link-color:            $brand-primary;
+$link-color:            $brand-primary !default;
 //** Link hover color set via `darken()` function.
-$link-hover-color:      $link-color;
+$link-hover-color:      $link-color !default;
 //** Link hover decoration.
-$link-hover-decoration: underline;
+$link-hover-decoration: underline !default;
 
 
 //== Typography
 //
 //## Font, line-height, and color for body text, headings, and more.
 
-$font-family-sans-serif:  "Source Sans Pro", "Helvetica Neue", Helvetica, Arial, sans-serif;
-$font-family-serif:       Georgia, "Times New Roman", Times, serif;
+$font-family-sans-serif:  "Source Sans Pro", "Helvetica Neue", Helvetica, Arial, sans-serif !default;
+$font-family-serif:       Georgia, "Times New Roman", Times, serif !default;
 //** Default monospace fonts for ``, ``, and `
`.
-$font-family-monospace:   Menlo, Monaco, Consolas, "Courier New", monospace;
-$font-family-base:        $font-family-sans-serif;
+$font-family-monospace:   Menlo, Monaco, Consolas, "Courier New", monospace !default;
+$font-family-base:        $font-family-sans-serif !default;
 
-$font-size-base:          14px;
-$font-size-large:         ceil(($font-size-base * 1.25)); // ~18px
-$font-size-small:         ceil(($font-size-base * 0.85)); // ~12px
+$font-size-base:          14px !default;
+$font-size-large:         ceil(($font-size-base * 1.25)) !default; // ~18px
+$font-size-small:         ceil(($font-size-base * 0.85)) !default; // ~12px
 
-$font-size-h1:            floor(($font-size-base * 2.6)); // ~36px
-$font-size-h2:            floor(($font-size-base * 2.15)); // ~30px
-$font-size-h3:            ceil(($font-size-base * 1.7)); // ~24px
-$font-size-h4:            ceil(($font-size-base * 1.25)); // ~18px
-$font-size-h5:            $font-size-base;
-$font-size-h6:            ceil(($font-size-base * 0.85)); // ~12px
+$font-size-h1:            floor(($font-size-base * 2.6)) !default; // ~36px
+$font-size-h2:            floor(($font-size-base * 2.15)) !default; // ~30px
+$font-size-h3:            ceil(($font-size-base * 1.7)) !default; // ~24px
+$font-size-h4:            ceil(($font-size-base * 1.25)) !default; // ~18px
+$font-size-h5:            $font-size-base !default;
+$font-size-h6:            ceil(($font-size-base * 0.85)) !default; // ~12px
 
 //** Unit-less `line-height` for use in components like buttons.
-$line-height-base:        1.428571429; // 20/14
+$line-height-base:        1.428571429 !default; // 20/14
 //** Computed "line-height" (`font-size` * `line-height`) for use with `margin`, `padding`, etc.
-$line-height-computed:    floor(($font-size-base * $line-height-base)); // ~20px
+$line-height-computed:    floor(($font-size-base * $line-height-base)) !default; // ~20px
 
 //** By default, this inherits from the ``.
-$headings-font-family:    inherit;
-$headings-font-weight:    400;
-$headings-line-height:    1.1;
-$headings-color:          $gray-dark;
+$headings-font-family:    inherit !default;
+$headings-font-weight:    400 !default;
+$headings-line-height:    1.1 !default;
+$headings-color:          $gray-dark !default;
 
 
 //== Iconography
@@ -76,45 +76,45 @@ $headings-color:          $gray-dark;
 //## Specify custom location and filename of the included Glyphicons icon font. Useful for those including Bootstrap via Bower.
 
 //** Load fonts from this directory.
-$icon-font-path:          "../fonts/";
+$icon-font-path:          "../fonts/" !default;
 //** File name for all font files.
-$icon-font-name:          "glyphicons-halflings-regular";
+$icon-font-name:          "glyphicons-halflings-regular" !default;
 //** Element ID within SVG icon file.
-$icon-font-svg-id:        "glyphicons_halflingsregular";
+$icon-font-svg-id:        "glyphicons_halflingsregular" !default;
 
 
 //== Components
 //
 //## Define common padding and border radius sizes and more. Values based on 14px text and 1.428 line-height (~20px to start).
 
-$padding-base-vertical:     7px;
-$padding-base-horizontal:   12px;
+$padding-base-vertical:     7px !default;
+$padding-base-horizontal:   12px !default;
 
-$padding-large-vertical:    13px;
-$padding-large-horizontal:  16px;
+$padding-large-vertical:    13px !default;
+$padding-large-horizontal:  16px !default;
 
-$padding-small-vertical:    4px;
-$padding-small-horizontal:  10px;
+$padding-small-vertical:    4px !default;
+$padding-small-horizontal:  10px !default;
 
-$padding-xs-vertical:       1px;
-$padding-xs-horizontal:     5px;
+$padding-xs-vertical:       1px !default;
+$padding-xs-horizontal:     5px !default;
 
-$line-height-large:         1.3333333; // extra decimals for Win 8.1 Chrome
-$line-height-small:         1.5;
+$line-height-large:         1.3333333 !default; // extra decimals for Win 8.1 Chrome
+$line-height-small:         1.5 !default;
 
-$border-radius-base:        4px;
-$border-radius-large:       5px;
-$border-radius-small:       2px;
+$border-radius-base:        4px !default;
+$border-radius-large:       5px !default;
+$border-radius-small:       2px !default;
 
 //** Global color for active items (e.g., navs or dropdowns).
-$component-active-color:    #fff;
+$component-active-color:    #fff !default;
 //** Global background color for active items (e.g., navs or dropdowns).
-$component-active-bg:       $brand-primary;
+$component-active-bg:       $brand-primary !default;
 
 //** Width of the `border` for generating carets that indicator dropdowns.
-$caret-width-base:          4px;
+$caret-width-base:          4px !default;
 //** Carets increase slightly in size for larger components.
-$caret-width-large:         5px;
+$caret-width-large:         5px !default;
 
 
 //== Tables
@@ -122,53 +122,53 @@ $caret-width-large:         5px;
 //## Customizes the `.table` component with basic values, each used across all table variations.
 
 //** Padding for ``s and ``s.
-$table-cell-padding:            8px;
+$table-cell-padding:            8px !default;
 //** Padding for cells in `.table-condensed`.
-$table-condensed-cell-padding:  5px;
+$table-condensed-cell-padding:  5px !default;
 
 //** Default background color used for all tables.
-$table-bg:                      transparent;
+$table-bg:                      transparent !default;
 //** Background color used for `.table-striped`.
-$table-bg-accent:               #f9f9f9;
+$table-bg-accent:               #f9f9f9 !default;
 //** Background color used for `.table-hover`.
-$table-bg-hover:                #f5f5f5;
-$table-bg-active:               $table-bg-hover;
+$table-bg-hover:                #f5f5f5 !default;
+$table-bg-active:               $table-bg-hover !default;
 
 //** Border color for table and cell borders.
-$table-border-color:            #ddd;
+$table-border-color:            #ddd !default;
 
 
 //== Buttons
 //
 //## For each of Bootstrap's buttons, define text, background and border color.
 
-$btn-font-weight:                normal;
+$btn-font-weight:                normal !default;
 
-$btn-default-color:              $gray;
-$btn-default-bg:                 $gray-lighter;
-$btn-default-border:             darken($btn-default-bg, 5%);
+$btn-default-color:              $gray !default;
+$btn-default-bg:                 $gray-lighter !default;
+$btn-default-border:             darken($btn-default-bg, 5%) !default;
 
-$btn-primary-color:              #fff;
-$btn-primary-bg:                 $brand-primary;
-$btn-primary-border:             darken($btn-primary-bg, 5%);
+$btn-primary-color:              #fff !default;
+$btn-primary-bg:                 $brand-primary !default;
+$btn-primary-border:             darken($btn-primary-bg, 5%) !default;
 
-$btn-success-color:              #fff;
-$btn-success-bg:                 $brand-success;
-$btn-success-border:             darken($btn-success-bg, 5%);
+$btn-success-color:              #fff !default;
+$btn-success-bg:                 $brand-success !default;
+$btn-success-border:             darken($btn-success-bg, 5%) !default;
 
-$btn-info-color:                 #fff;
-$btn-info-bg:                    $brand-info;
-$btn-info-border:                darken($btn-info-bg, 5%);
+$btn-info-color:                 #fff !default;
+$btn-info-bg:                    $brand-info !default;
+$btn-info-border:                darken($btn-info-bg, 5%) !default;
 
-$btn-warning-color:              #fff;
-$btn-warning-bg:                 $brand-warning;
-$btn-warning-border:             darken($btn-warning-bg, 5%);
+$btn-warning-color:              #fff !default;
+$btn-warning-bg:                 $brand-warning !default;
+$btn-warning-border:             darken($btn-warning-bg, 5%) !default;
 
-$btn-danger-color:               #fff;
-$btn-danger-bg:                  $brand-danger;
-$btn-danger-border:              darken($btn-danger-bg, 5%);
+$btn-danger-color:               #fff !default;
+$btn-danger-bg:                  $brand-danger !default;
+$btn-danger-border:              darken($btn-danger-bg, 5%) !default;
 
-$btn-link-disabled-color:        $gray-light;
+$btn-link-disabled-color:        $gray-light !default;
 
 
 //== Forms
@@ -176,50 +176,50 @@ $btn-link-disabled-color:        $gray-light;
 //##
 
 //** `` background color
-$input-bg:                       #fff;
+$input-bg:                       #fff !default;
 //** `` background color
-$input-bg-disabled:              $gray-lighter;
+$input-bg-disabled:              $gray-lighter !default;
 
 //** Text color for ``s
-$input-color:                    $gray;
+$input-color:                    $gray !default;
 //** `` border color
-$input-border:                   darken(#f8f8f8, 6.5%);
+$input-border:                   darken(#f8f8f8, 6.5%) !default;
 
 // TODO: Rename `$input-border-radius` to `$input-border-radius-base` in v4
 //** Default `.form-control` border radius
 // This has no effect on ``s in CSS.
-$input-border-radius:            $border-radius-base;
+$input-border-radius:            $border-radius-base !default;
 //** Large `.form-control` border radius
-$input-border-radius-large:      $border-radius-large;
+$input-border-radius-large:      $border-radius-large !default;
 //** Small `.form-control` border radius
-$input-border-radius-small:      $border-radius-small;
+$input-border-radius-small:      $border-radius-small !default;
 
 //** Border color for inputs on focus
-$input-border-focus:             #66afe9;
+$input-border-focus:             #66afe9 !default;
 
 //** Placeholder text color
-$input-color-placeholder:        $gray-light;
+$input-color-placeholder:        $gray-light !default;
 
 //** Default `.form-control` height
-$input-height-base:              ($line-height-computed + ($padding-base-vertical * 2) + 4);
+$input-height-base:              ($line-height-computed + ($padding-base-vertical * 2) + 4) !default;
 //** Large `.form-control` height
-$input-height-large:             (ceil($font-size-large * $line-height-large) + ($padding-large-vertical * 2) + 2);
+$input-height-large:             (ceil($font-size-large * $line-height-large) + ($padding-large-vertical * 2) + 2) !default;
 //** Small `.form-control` height
-$input-height-small:             (floor($font-size-small * $line-height-small) + ($padding-small-vertical * 2) + 2);
+$input-height-small:             (floor($font-size-small * $line-height-small) + ($padding-small-vertical * 2) + 2) !default;
 
 //** `.form-group` margin
-$form-group-margin-bottom:       15px;
+$form-group-margin-bottom:       15px !default;
 
-$legend-color:                   $gray-dark;
-$legend-border-color:            #e5e5e5;
+$legend-color:                   $gray-dark !default;
+$legend-border-color:            #e5e5e5 !default;
 
 //** Background color for textual input addons
-$input-group-addon-bg:           $gray-lighter;
+$input-group-addon-bg:           $gray-lighter !default;
 //** Border color for textual input addons
-$input-group-addon-border-color: $input-border;
+$input-group-addon-border-color: $input-border !default;
 
 //** Disabled cursor for form controls and buttons.
-$cursor-disabled:                not-allowed;
+$cursor-disabled:                not-allowed !default;
 
 
 //== Dropdowns
@@ -227,34 +227,34 @@ $cursor-disabled:                not-allowed;
 //## Dropdown menu container and contents.
 
 //** Background for the dropdown menu.
-$dropdown-bg:                    #fff;
+$dropdown-bg:                    #fff !default;
 //** Dropdown menu `border-color`.
-$dropdown-border:                $input-border;
+$dropdown-border:                $input-border !default;
 //** Dropdown menu `border-color` **for IE8**.
-$dropdown-fallback-border:       #ccc;
+$dropdown-fallback-border:       #ccc !default;
 //** Divider color for between dropdown items.
-$dropdown-divider-bg:            $gray-lighter;
+$dropdown-divider-bg:            $gray-lighter !default;
 
 //** Dropdown link text color.
-$dropdown-link-color:            $gray-light;
+$dropdown-link-color:            $gray-light !default;
 //** Hover color for dropdown links.
-$dropdown-link-hover-color:      $gray-dark;
+$dropdown-link-hover-color:      $gray-dark !default;
 //** Hover background for dropdown links.
-$dropdown-link-hover-bg:         transparent;
+$dropdown-link-hover-bg:         transparent !default;
 
 //** Active dropdown menu item text color.
-$dropdown-link-active-color:     $component-active-color;
+$dropdown-link-active-color:     $component-active-color !default;
 //** Active dropdown menu item background color.
-$dropdown-link-active-bg:        $component-active-bg;
+$dropdown-link-active-bg:        $component-active-bg !default;
 
 //** Disabled dropdown menu item background color.
-$dropdown-link-disabled-color:   $gray-lighter;
+$dropdown-link-disabled-color:   $gray-lighter !default;
 
 //** Text color for headers within dropdown menus.
-$dropdown-header-color:          $gray-light;
+$dropdown-header-color:          $gray-light !default;
 
 //** Deprecated `$dropdown-caret-color` as of v3.1.0
-$dropdown-caret-color:           #000;
+$dropdown-caret-color:           #000 !default;
 
 
 //-- Z-index master list
@@ -264,13 +264,13 @@ $dropdown-caret-color:           #000;
 //
 // Note: These variables are not generated into the Customizer.
 
-$zindex-navbar:            1000;
-$zindex-dropdown:          1000;
-$zindex-popover:           1060;
-$zindex-tooltip:           1070;
-$zindex-navbar-fixed:      1030;
-$zindex-modal-background:  1040;
-$zindex-modal:             1050;
+$zindex-navbar:            1000 !default;
+$zindex-dropdown:          1000 !default;
+$zindex-popover:           1060 !default;
+$zindex-tooltip:           1070 !default;
+$zindex-navbar-fixed:      1030 !default;
+$zindex-modal-background:  1040 !default;
+$zindex-modal:             1050 !default;
 
 
 //== Media queries breakpoints
@@ -279,37 +279,37 @@ $zindex-modal:             1050;
 
 // Extra small screen / phone
 //** Deprecated `$screen-xs` as of v3.0.1
-$screen-xs:                  480px;
+$screen-xs:                  480px !default;
 //** Deprecated `$screen-xs-min` as of v3.2.0
-$screen-xs-min:              $screen-xs;
+$screen-xs-min:              $screen-xs !default;
 //** Deprecated `$screen-phone` as of v3.0.1
-$screen-phone:               $screen-xs-min;
+$screen-phone:               $screen-xs-min !default;
 
 // Small screen / tablet
 //** Deprecated `$screen-sm` as of v3.0.1
-$screen-sm:                  768px;
-$screen-sm-min:              $screen-sm;
+$screen-sm:                  768px !default;
+$screen-sm-min:              $screen-sm !default;
 //** Deprecated `$screen-tablet` as of v3.0.1
-$screen-tablet:              $screen-sm-min;
+$screen-tablet:              $screen-sm-min !default;
 
 // Medium screen / desktop
 //** Deprecated `$screen-md` as of v3.0.1
-$screen-md:                  992px;
-$screen-md-min:              $screen-md;
+$screen-md:                  992px !default;
+$screen-md-min:              $screen-md !default;
 //** Deprecated `$screen-desktop` as of v3.0.1
-$screen-desktop:             $screen-md-min;
+$screen-desktop:             $screen-md-min !default;
 
 // Large screen / wide desktop
 //** Deprecated `$screen-lg` as of v3.0.1
-$screen-lg:                  1200px;
-$screen-lg-min:              $screen-lg;
+$screen-lg:                  1200px !default;
+$screen-lg-min:              $screen-lg !default;
 //** Deprecated `$screen-lg-desktop` as of v3.0.1
-$screen-lg-desktop:          $screen-lg-min;
+$screen-lg-desktop:          $screen-lg-min !default;
 
 // So media queries don't overlap when required, provide a maximum
-$screen-xs-max:              ($screen-sm-min - 1);
-$screen-sm-max:              ($screen-md-min - 1);
-$screen-md-max:              ($screen-lg-min - 1);
+$screen-xs-max:              ($screen-sm-min - 1) !default;
+$screen-sm-max:              ($screen-md-min - 1) !default;
+$screen-md-max:              ($screen-lg-min - 1) !default;
 
 
 //== Grid system
@@ -317,14 +317,14 @@ $screen-md-max:              ($screen-lg-min - 1);
 //## Define your custom responsive grid.
 
 //** Number of columns in the grid.
-$grid-columns:              12;
+$grid-columns:              12 !default;
 //** Padding between columns. Gets divided in half for the left and right.
-$grid-gutter-width:         30px;
+$grid-gutter-width:         30px !default;
 // Navbar collapse
 //** Point at which the navbar becomes uncollapsed.
-$grid-float-breakpoint:     $screen-sm-min;
+$grid-float-breakpoint:     $screen-sm-min !default;
 //** Point at which the navbar begins collapsing.
-$grid-float-breakpoint-max: ($grid-float-breakpoint - 1);
+$grid-float-breakpoint-max: ($grid-float-breakpoint - 1) !default;
 
 
 //== Container sizes
@@ -332,19 +332,19 @@ $grid-float-breakpoint-max: ($grid-float-breakpoint - 1);
 //## Define the maximum width of `.container` for different screen sizes.
 
 // Small screen / tablet
-$container-tablet:             (720px + $grid-gutter-width);
+$container-tablet:             (720px + $grid-gutter-width) !default;
 //** For `$screen-sm-min` and up.
-$container-sm:                 $container-tablet;
+$container-sm:                 $container-tablet !default;
 
 // Medium screen / desktop
-$container-desktop:            (940px + $grid-gutter-width);
+$container-desktop:            (940px + $grid-gutter-width) !default;
 //** For `$screen-md-min` and up.
-$container-md:                 $container-desktop;
+$container-md:                 $container-desktop !default;
 
 // Large screen / wide desktop
-$container-large-desktop:      (1140px + $grid-gutter-width);
+$container-large-desktop:      (1140px + $grid-gutter-width) !default;
 //** For `$screen-lg-min` and up.
-$container-lg:                 $container-large-desktop;
+$container-lg:                 $container-large-desktop !default;
 
 
 //== Navbar
@@ -352,61 +352,61 @@ $container-lg:                 $container-large-desktop;
 //##
 
 // Basics of a navbar
-$navbar-height:                    50px;
-$navbar-margin-bottom:             $line-height-computed;
-$navbar-border-radius:             $border-radius-base;
-$navbar-padding-horizontal:        floor(($grid-gutter-width / 2));
-$navbar-padding-vertical:          (($navbar-height - $line-height-computed) / 2);
-$navbar-collapse-max-height:       340px;
+$navbar-height:                    50px !default;
+$navbar-margin-bottom:             $line-height-computed !default;
+$navbar-border-radius:             $border-radius-base !default;
+$navbar-padding-horizontal:        floor(($grid-gutter-width / 2)) !default;
+$navbar-padding-vertical:          (($navbar-height - $line-height-computed) / 2) !default;
+$navbar-collapse-max-height:       340px !default;
 
-$navbar-default-color:             $text-color;
-$navbar-default-bg:                #f8f8f8;
-$navbar-default-border:            $input-border;
+$navbar-default-color:             $text-color !default;
+$navbar-default-bg:                #f8f8f8 !default;
+$navbar-default-border:            $input-border !default;
 
 // Navbar links
-$navbar-default-link-color:                $gray-light;
-$navbar-default-link-hover-color:          $gray-dark;
-$navbar-default-link-hover-bg:             transparent;
-$navbar-default-link-active-color:         $navbar-default-link-hover-color;
-$navbar-default-link-active-bg:            transparent;
-$navbar-default-link-disabled-color:       $gray-lighter;
-$navbar-default-link-disabled-bg:          transparent;
+$navbar-default-link-color:                $gray-light !default;
+$navbar-default-link-hover-color:          $gray-dark !default;
+$navbar-default-link-hover-bg:             transparent !default;
+$navbar-default-link-active-color:         $navbar-default-link-hover-color !default;
+$navbar-default-link-active-bg:            transparent !default;
+$navbar-default-link-disabled-color:       $gray-lighter !default;
+$navbar-default-link-disabled-bg:          transparent !default;
 
 // Navbar brand label
-$navbar-default-brand-color:               $navbar-default-link-hover-color;
-$navbar-default-brand-hover-color:         $navbar-default-link-hover-color;
-$navbar-default-brand-hover-bg:            transparent;
+$navbar-default-brand-color:               $navbar-default-link-hover-color !default;
+$navbar-default-brand-hover-color:         $navbar-default-link-hover-color !default;
+$navbar-default-brand-hover-bg:            transparent !default;
 
 // Navbar toggle
-$navbar-default-toggle-hover-bg:           #fff;
-$navbar-default-toggle-icon-bar-bg:        $gray-light;
-$navbar-default-toggle-border-color:       $gray-lighter;
+$navbar-default-toggle-hover-bg:           #fff !default;
+$navbar-default-toggle-icon-bar-bg:        $gray-light !default;
+$navbar-default-toggle-border-color:       $gray-lighter !default;
 
 
 // Inverted navbar
 // Reset inverted navbar basics
-$navbar-inverse-color:                      $gray-light;
-$navbar-inverse-bg:                         #fff;
-$navbar-inverse-border:                     darken($navbar-inverse-bg, 10%);
+$navbar-inverse-color:                      $gray-light !default;
+$navbar-inverse-bg:                         #fff !default;
+$navbar-inverse-border:                     darken($navbar-inverse-bg, 10%) !default;
 
 // Inverted navbar links
-$navbar-inverse-link-color:                 $gray-light;
-$navbar-inverse-link-hover-color:           $gray-dark;
-$navbar-inverse-link-hover-bg:              transparent;
-$navbar-inverse-link-active-color:          $navbar-inverse-link-hover-color;
-$navbar-inverse-link-active-bg:             transparent;
-$navbar-inverse-link-disabled-color:        $gray-lighter;
-$navbar-inverse-link-disabled-bg:           transparent;
+$navbar-inverse-link-color:                 $gray-light !default;
+$navbar-inverse-link-hover-color:           $gray-dark !default;
+$navbar-inverse-link-hover-bg:              transparent !default;
+$navbar-inverse-link-active-color:          $navbar-inverse-link-hover-color !default;
+$navbar-inverse-link-active-bg:             transparent !default;
+$navbar-inverse-link-disabled-color:        $gray-lighter !default;
+$navbar-inverse-link-disabled-bg:           transparent !default;
 
 // Inverted navbar brand label
-$navbar-inverse-brand-color:                $navbar-inverse-link-color;
-$navbar-inverse-brand-hover-color:          $navbar-inverse-link-hover-color;
-$navbar-inverse-brand-hover-bg:             transparent;
+$navbar-inverse-brand-color:                $navbar-inverse-link-color !default;
+$navbar-inverse-brand-hover-color:          $navbar-inverse-link-hover-color !default;
+$navbar-inverse-brand-hover-bg:             transparent !default;
 
 // Inverted navbar toggle
-$navbar-inverse-toggle-hover-bg:            $gray-lighter;
-$navbar-inverse-toggle-icon-bar-bg:         $gray-light;
-$navbar-inverse-toggle-border-color:        $gray-lighter;
+$navbar-inverse-toggle-hover-bg:            $gray-lighter !default;
+$navbar-inverse-toggle-icon-bar-bg:         $gray-light !default;
+$navbar-inverse-toggle-border-color:        $gray-lighter !default;
 
 
 //== Navs
@@ -414,97 +414,97 @@ $navbar-inverse-toggle-border-color:        $gray-lighter;
 //##
 
 //=== Shared nav styles
-$nav-link-padding:                          10px 15px;
-$nav-link-hover-bg:                         #fff;
+$nav-link-padding:                          10px 15px !default;
+$nav-link-hover-bg:                         #fff !default;
 
-$nav-disabled-link-color:                   $gray-light;
-$nav-disabled-link-hover-color:             $gray-light;
+$nav-disabled-link-color:                   $gray-light !default;
+$nav-disabled-link-hover-color:             $gray-light !default;
 
 //== Tabs
-$nav-tabs-border-color:                     $navbar-default-border;
+$nav-tabs-border-color:                     $navbar-default-border !default;
 
-$nav-tabs-link-hover-border-color:          $gray-lighter;
+$nav-tabs-link-hover-border-color:          $gray-lighter !default;
 
-$nav-tabs-active-link-hover-bg:             #fff;
-$nav-tabs-active-link-hover-color:          $gray;
-$nav-tabs-active-link-hover-border-color:   $nav-tabs-border-color;
+$nav-tabs-active-link-hover-bg:             #fff !default;
+$nav-tabs-active-link-hover-color:          $gray !default;
+$nav-tabs-active-link-hover-border-color:   $nav-tabs-border-color !default;
 
-$nav-tabs-justified-link-border-color:            $nav-tabs-border-color;
-$nav-tabs-justified-active-link-border-color:     $body-bg;
+$nav-tabs-justified-link-border-color:            $nav-tabs-border-color !default;
+$nav-tabs-justified-active-link-border-color:     $body-bg !default;
 
 //== Pills
-$nav-pills-border-radius:                   $border-radius-base;
-$nav-pills-active-link-hover-bg:            $component-active-bg;
-$nav-pills-active-link-hover-color:         $component-active-color;
+$nav-pills-border-radius:                   $border-radius-base !default;
+$nav-pills-active-link-hover-bg:            $component-active-bg !default;
+$nav-pills-active-link-hover-color:         $component-active-color !default;
 
 
 //== Pagination
 //
 //##
 
-$pagination-color:                     $btn-default-color;
-$pagination-bg:                        $btn-default-bg;
-$pagination-border:                    $btn-default-border;
+$pagination-color:                     $btn-default-color !default;
+$pagination-bg:                        $btn-default-bg !default;
+$pagination-border:                    $btn-default-border !default;
 
-$pagination-hover-color:               $pagination-color;
-$pagination-hover-bg:                  $pagination-bg;
-$pagination-hover-border:              $pagination-border;
+$pagination-hover-color:               $pagination-color !default;
+$pagination-hover-bg:                  $pagination-bg !default;
+$pagination-hover-border:              $pagination-border !default;
 
-$pagination-active-color:              #fff;
-$pagination-active-bg:                 $brand-primary;
-$pagination-active-border:             $btn-primary-border;
+$pagination-active-color:              #fff !default;
+$pagination-active-bg:                 $brand-primary !default;
+$pagination-active-border:             $btn-primary-border !default;
 
-$pagination-disabled-color:            $gray-light;
-$pagination-disabled-bg:               $pagination-bg;
-$pagination-disabled-border:           $pagination-border;
+$pagination-disabled-color:            $gray-light !default;
+$pagination-disabled-bg:               $pagination-bg !default;
+$pagination-disabled-border:           $pagination-border !default;
 
 
 //== Pager
 //
 //##
 
-$pager-bg:                             $pagination-bg;
-$pager-border:                         $pagination-border;
-$pager-border-radius:                  15px;
+$pager-bg:                             $pagination-bg !default;
+$pager-border:                         $pagination-border !default;
+$pager-border-radius:                  15px !default;
 
-$pager-hover-bg:                       $pagination-hover-bg;
+$pager-hover-bg:                       $pagination-hover-bg !default;
 
-$pager-active-bg:                      $pagination-active-bg;
-$pager-active-color:                   $pagination-active-color;
+$pager-active-bg:                      $pagination-active-bg !default;
+$pager-active-color:                   $pagination-active-color !default;
 
-$pager-disabled-color:                 $pagination-disabled-color;
+$pager-disabled-color:                 $pagination-disabled-color !default;
 
 
 //== Jumbotron
 //
 //##
 
-$jumbotron-padding:              30px;
-$jumbotron-color:                inherit;
-$jumbotron-bg:                   #fafafa;
-$jumbotron-heading-color:        inherit;
-$jumbotron-font-size:            ceil(($font-size-base * 1.5));
+$jumbotron-padding:              30px !default;
+$jumbotron-color:                inherit !default;
+$jumbotron-bg:                   #fafafa !default;
+$jumbotron-heading-color:        inherit !default;
+$jumbotron-font-size:            ceil(($font-size-base * 1.5)) !default;
 
 
 //== Form states and alerts
 //
 //## Define colors for form feedback states and, by default, alerts.
 
-$state-success-text:             #fff;
-$state-success-bg:               $brand-success;
-$state-success-border:           darken($state-success-bg, 4%);
+$state-success-text:             #fff !default;
+$state-success-bg:               $brand-success !default;
+$state-success-border:           darken($state-success-bg, 4%) !default;
 
-$state-info-text:                #fff;
-$state-info-bg:                  $brand-info;
-$state-info-border:              darken($state-info-bg, 12%);
+$state-info-text:                #fff !default;
+$state-info-bg:                  $brand-info !default;
+$state-info-border:              darken($state-info-bg, 12%) !default;
 
-$state-warning-text:             #fff;
-$state-warning-bg:               $brand-warning;
-$state-warning-border:           darken($state-warning-bg, 5%);
+$state-warning-text:             #fff !default;
+$state-warning-bg:               $brand-warning !default;
+$state-warning-border:           darken($state-warning-bg, 5%) !default;
 
-$state-danger-text:              #fff;
-$state-danger-bg:                $brand-danger;
-$state-danger-border:            darken($state-danger-bg, 10%);
+$state-danger-text:              #fff !default;
+$state-danger-bg:                $brand-danger !default;
+$state-danger-border:            darken($state-danger-bg, 10%) !default;
 
 
 //== Tooltips
@@ -512,17 +512,17 @@ $state-danger-border:            darken($state-danger-bg, 10%);
 //##
 
 //** Tooltip max width
-$tooltip-max-width:           200px;
+$tooltip-max-width:           200px !default;
 //** Tooltip text color
-$tooltip-color:               #fff;
+$tooltip-color:               #fff !default;
 //** Tooltip background color
-$tooltip-bg:                  #000;
-$tooltip-opacity:             .9;
+$tooltip-bg:                  #000 !default;
+$tooltip-opacity:             .9 !default;
 
 //** Tooltip arrow width
-$tooltip-arrow-width:         5px;
+$tooltip-arrow-width:         5px !default;
 //** Tooltip arrow color
-$tooltip-arrow-color:         $tooltip-bg;
+$tooltip-arrow-color:         $tooltip-bg !default;
 
 
 //== Popovers
@@ -530,28 +530,28 @@ $tooltip-arrow-color:         $tooltip-bg;
 //##
 
 //** Popover body background color
-$popover-bg:                          #fff;
+$popover-bg:                          #fff !default;
 //** Popover maximum width
-$popover-max-width:                   276px;
+$popover-max-width:                   276px !default;
 //** Popover border color
-$popover-border-color:                rgba(0,0,0,.2);
+$popover-border-color:                rgba(0,0,0,.2) !default;
 //** Popover fallback border color
-$popover-fallback-border-color:       #ccc;
+$popover-fallback-border-color:       #ccc !default;
 
 //** Popover title background color
-$popover-title-bg:                    darken($popover-bg, 3%);
+$popover-title-bg:                    darken($popover-bg, 3%) !default;
 
 //** Popover arrow width
-$popover-arrow-width:                 10px;
+$popover-arrow-width:                 10px !default;
 //** Popover arrow color
-$popover-arrow-color:                 $popover-bg;
+$popover-arrow-color:                 $popover-bg !default;
 
 //** Popover outer arrow width
-$popover-arrow-outer-width:           ($popover-arrow-width + 1);
+$popover-arrow-outer-width:           ($popover-arrow-width + 1) !default;
 //** Popover outer arrow color
-$popover-arrow-outer-color:           fadein($popover-border-color, 5%);
+$popover-arrow-outer-color:           fadein($popover-border-color, 5%) !default;
 //** Popover outer arrow fallback color
-$popover-arrow-outer-fallback-color:  darken($popover-fallback-border-color, 20%);
+$popover-arrow-outer-fallback-color:  darken($popover-fallback-border-color, 20%) !default;
 
 
 //== Labels
@@ -559,22 +559,22 @@ $popover-arrow-outer-fallback-color:  darken($popover-fallback-border-color, 20%
 //##
 
 //** Default label background color
-$label-default-bg:            $gray-light;
+$label-default-bg:            $gray-light !default;
 //** Primary label background color
-$label-primary-bg:            $brand-primary;
+$label-primary-bg:            $brand-primary !default;
 //** Success label background color
-$label-success-bg:            $brand-success;
+$label-success-bg:            $brand-success !default;
 //** Info label background color
-$label-info-bg:               $brand-info;
+$label-info-bg:               $brand-info !default;
 //** Warning label background color
-$label-warning-bg:            $brand-warning;
+$label-warning-bg:            $brand-warning !default;
 //** Danger label background color
-$label-danger-bg:             $brand-danger;
+$label-danger-bg:             $brand-danger !default;
 
 //** Default label text color
-$label-color:                 #fff;
+$label-color:                 #fff !default;
 //** Default text color of a linked label
-$label-link-hover-color:      #fff;
+$label-link-hover-color:      #fff !default;
 
 
 //== Modals
@@ -582,57 +582,57 @@ $label-link-hover-color:      #fff;
 //##
 
 //** Padding applied to the modal body
-$modal-inner-padding:         20px;
+$modal-inner-padding:         20px !default;
 
 //** Padding applied to the modal title
-$modal-title-padding:         15px;
+$modal-title-padding:         15px !default;
 //** Modal title line-height
-$modal-title-line-height:     $line-height-base;
+$modal-title-line-height:     $line-height-base !default;
 
 //** Background color of modal content area
-$modal-content-bg:                             #fff;
+$modal-content-bg:                             #fff !default;
 //** Modal content border color
-$modal-content-border-color:                   rgba(0,0,0,.2);
+$modal-content-border-color:                   rgba(0,0,0,.2) !default;
 //** Modal content border color **for IE8**
-$modal-content-fallback-border-color:          #999;
+$modal-content-fallback-border-color:          #999 !default;
 
 //** Modal backdrop background color
-$modal-backdrop-bg:           #000;
+$modal-backdrop-bg:           #000 !default;
 //** Modal backdrop opacity
-$modal-backdrop-opacity:      .5;
+$modal-backdrop-opacity:      .5 !default;
 //** Modal header border color
-$modal-header-border-color:   #e5e5e5;
+$modal-header-border-color:   #e5e5e5 !default;
 //** Modal footer border color
-$modal-footer-border-color:   $modal-header-border-color;
+$modal-footer-border-color:   $modal-header-border-color !default;
 
-$modal-lg:                    900px;
-$modal-md:                    600px;
-$modal-sm:                    300px;
+$modal-lg:                    900px !default;
+$modal-md:                    600px !default;
+$modal-sm:                    300px !default;
 
 
 //== Alerts
 //
 //## Define alert colors, border radius, and padding.
 
-$alert-padding:               15px;
-$alert-border-radius:         $border-radius-base;
-$alert-link-font-weight:      bold;
+$alert-padding:               15px !default;
+$alert-border-radius:         $border-radius-base !default;
+$alert-link-font-weight:      bold !default;
 
-$alert-success-bg:            $state-success-bg;
-$alert-success-text:          $state-success-text;
-$alert-success-border:        $state-success-border;
+$alert-success-bg:            $state-success-bg !default;
+$alert-success-text:          $state-success-text !default;
+$alert-success-border:        $state-success-border !default;
 
-$alert-info-bg:               $state-info-bg;
-$alert-info-text:             $state-info-text;
-$alert-info-border:           $state-info-border;
+$alert-info-bg:               $state-info-bg !default;
+$alert-info-text:             $state-info-text !default;
+$alert-info-border:           $state-info-border !default;
 
-$alert-warning-bg:            $state-warning-bg;
-$alert-warning-text:          $state-warning-text;
-$alert-warning-border:        $state-warning-border;
+$alert-warning-bg:            $state-warning-bg !default;
+$alert-warning-text:          $state-warning-text !default;
+$alert-warning-border:        $state-warning-border !default;
 
-$alert-danger-bg:             $state-danger-bg;
-$alert-danger-text:           $state-danger-text;
-$alert-danger-border:         $state-danger-border;
+$alert-danger-bg:             $state-danger-bg !default;
+$alert-danger-text:           $state-danger-text !default;
+$alert-danger-border:         $state-danger-border !default;
 
 
 //== Progress bars
@@ -640,22 +640,22 @@ $alert-danger-border:         $state-danger-border;
 //##
 
 //** Background color of the whole progress component
-$progress-bg:                 $jumbotron-bg;
+$progress-bg:                 $jumbotron-bg !default;
 //** Progress bar text color
-$progress-bar-color:          #fff;
+$progress-bar-color:          #fff !default;
 //** Variable for setting rounded corners on progress bar.
-$progress-border-radius:      $border-radius-base;
+$progress-border-radius:      $border-radius-base !default;
 
 //** Default progress bar color
-$progress-bar-bg:             $brand-primary;
+$progress-bar-bg:             $brand-primary !default;
 //** Success progress bar color
-$progress-bar-success-bg:     $brand-success;
+$progress-bar-success-bg:     $brand-success !default;
 //** Warning progress bar color
-$progress-bar-warning-bg:     $brand-warning;
+$progress-bar-warning-bg:     $brand-warning !default;
 //** Danger progress bar color
-$progress-bar-danger-bg:      $brand-danger;
+$progress-bar-danger-bg:      $brand-danger !default;
 //** Info progress bar color
-$progress-bar-info-bg:        $brand-info;
+$progress-bar-info-bg:        $brand-info !default;
 
 
 //== List group
@@ -663,72 +663,72 @@ $progress-bar-info-bg:        $brand-info;
 //##
 
 //** Background color on `.list-group-item`
-$list-group-bg:                 #fff;
+$list-group-bg:                 #fff !default;
 //** `.list-group-item` border color
-$list-group-border:             #ddd;
+$list-group-border:             #ddd !default;
 //** List group border radius
-$list-group-border-radius:      $border-radius-base;
+$list-group-border-radius:      $border-radius-base !default;
 
 //** Background color of single list items on hover
-$list-group-hover-bg:           #f5f5f5;
+$list-group-hover-bg:           #f5f5f5 !default;
 //** Text color of active list items
-$list-group-active-color:       $component-active-color;
+$list-group-active-color:       $component-active-color !default;
 //** Background color of active list elements
-$list-group-active-bg:          $component-active-bg;
+$list-group-active-bg:          $component-active-bg !default;
 //** Background color of active list items
-$list-group-active-border:      $list-group-active-bg;
+$list-group-active-border:      $list-group-active-bg !default;
 //** Text color for content within active list items
-$list-group-active-text-color:  lighten($list-group-active-bg, 40%);
+$list-group-active-text-color:  lighten($list-group-active-bg, 40%) !default;
 
 //** Text color of disabled list items
-$list-group-disabled-color:      $gray-light;
+$list-group-disabled-color:      $gray-light !default;
 //** Background color of disabled list items
-$list-group-disabled-bg:         $gray-lighter;
+$list-group-disabled-bg:         $gray-lighter !default;
 //** Text color for content within disabled list items
-$list-group-disabled-text-color: $list-group-disabled-color;
+$list-group-disabled-text-color: $list-group-disabled-color !default;
 
-$list-group-link-color:         #555;
-$list-group-link-hover-color:   $list-group-link-color;
-$list-group-link-heading-color: #333;
+$list-group-link-color:         #555 !default;
+$list-group-link-hover-color:   $list-group-link-color !default;
+$list-group-link-heading-color: #333 !default;
 
 
 //== Panels
 //
 //##
 
-$panel-bg:                    #fff;
-$panel-body-padding:          15px;
-$panel-heading-padding:       10px 15px;
-$panel-footer-padding:        $panel-heading-padding;
-$panel-border-radius:         $border-radius-base;
+$panel-bg:                    #fff !default;
+$panel-body-padding:          15px !default;
+$panel-heading-padding:       10px 15px !default;
+$panel-footer-padding:        $panel-heading-padding !default;
+$panel-border-radius:         $border-radius-base !default;
 
 //** Border color for elements within panels
-$panel-inner-border:          transparent;
-$panel-footer-bg:             #f5f5f5;
+$panel-inner-border:          transparent !default;
+$panel-footer-bg:             #f5f5f5 !default;
 
-$panel-default-text:          $gray-dark;
-$panel-default-border:        transparent;
-$panel-default-heading-bg:    #f5f5f5;
+$panel-default-text:          $gray-dark !default;
+$panel-default-border:        transparent !default;
+$panel-default-heading-bg:    #f5f5f5 !default;
 
-$panel-primary-text:          #fff;
-$panel-primary-border:        transparent;
-$panel-primary-heading-bg:    $brand-primary;
+$panel-primary-text:          #fff !default;
+$panel-primary-border:        transparent !default;
+$panel-primary-heading-bg:    $brand-primary !default;
 
-$panel-success-text:          $state-success-text;
-$panel-success-border:        transparent;
-$panel-success-heading-bg:    $state-success-bg;
+$panel-success-text:          $state-success-text !default;
+$panel-success-border:        transparent !default;
+$panel-success-heading-bg:    $state-success-bg !default;
 
-$panel-info-text:             $state-info-text;
-$panel-info-border:           transparent;
-$panel-info-heading-bg:       $state-info-bg;
+$panel-info-text:             $state-info-text !default;
+$panel-info-border:           transparent !default;
+$panel-info-heading-bg:       $state-info-bg !default;
 
-$panel-warning-text:          $state-warning-text;
-$panel-warning-border:        transparent;
-$panel-warning-heading-bg:    $state-warning-bg;
+$panel-warning-text:          $state-warning-text !default;
+$panel-warning-border:        transparent !default;
+$panel-warning-heading-bg:    $state-warning-bg !default;
 
-$panel-danger-text:           $state-danger-text;
-$panel-danger-border:         transparent;
-$panel-danger-heading-bg:     $state-danger-bg;
+$panel-danger-text:           $state-danger-text !default;
+$panel-danger-border:         transparent !default;
+$panel-danger-heading-bg:     $state-danger-bg !default;
 
 
 //== Thumbnails
@@ -736,103 +736,103 @@ $panel-danger-heading-bg:     $state-danger-bg;
 //##
 
 //** Padding around the thumbnail image
-$thumbnail-padding:           4px;
+$thumbnail-padding:           4px !default;
 //** Thumbnail background color
-$thumbnail-bg:                $body-bg;
+$thumbnail-bg:                $body-bg !default;
 //** Thumbnail border color
-$thumbnail-border:            $gray-lighter;
+$thumbnail-border:            $gray-lighter !default;
 //** Thumbnail border radius
-$thumbnail-border-radius:     $border-radius-base;
+$thumbnail-border-radius:     $border-radius-base !default;
 
 //** Custom text color for thumbnail captions
-$thumbnail-caption-color:     $text-color;
+$thumbnail-caption-color:     $text-color !default;
 //** Padding around the thumbnail caption
-$thumbnail-caption-padding:   9px;
+$thumbnail-caption-padding:   9px !default;
 
 
 //== Wells
 //
 //##
 
-$well-bg:                     $jumbotron-bg;
-$well-border:                 darken($well-bg, 7%);
+$well-bg:                     $jumbotron-bg !default;
+$well-border:                 darken($well-bg, 7%) !default;
 
 
 //== Badges
 //
 //##
 
-$badge-color:                 #fff;
+$badge-color:                 #fff !default;
 //** Linked badge text color on hover
-$badge-link-hover-color:      #fff;
-$badge-bg:                    $brand-primary;
+$badge-link-hover-color:      #fff !default;
+$badge-bg:                    $brand-primary !default;
 
 //** Badge text color in active nav link
-$badge-active-color:          $link-color;
+$badge-active-color:          $link-color !default;
 //** Badge background color in active nav link
-$badge-active-bg:             #fff;
+$badge-active-bg:             #fff !default;
 
-$badge-font-weight:           normal;
-$badge-line-height:           1;
-$badge-border-radius:         10px;
+$badge-font-weight:           normal !default;
+$badge-line-height:           1 !default;
+$badge-border-radius:         10px !default;
 
 
 //== Breadcrumbs
 //
 //##
 
-$breadcrumb-padding-vertical:   8px;
-$breadcrumb-padding-horizontal: 15px;
+$breadcrumb-padding-vertical:   8px !default;
+$breadcrumb-padding-horizontal: 15px !default;
 //** Breadcrumb background color
-$breadcrumb-bg:                 $well-bg;
+$breadcrumb-bg:                 $well-bg !default;
 //** Breadcrumb text color
-$breadcrumb-color:              $gray-light;
+$breadcrumb-color:              $gray-light !default;
 //** Text color of current page in the breadcrumb
-$breadcrumb-active-color:       $gray-light;
+$breadcrumb-active-color:       $gray-light !default;
 //** Textual separator for between breadcrumb elements
-$breadcrumb-separator:          ">";
+$breadcrumb-separator:          ">" !default;
 
 
 //== Carousel
 //
 //##
 
-$carousel-text-shadow:                        0 1px 2px rgba(0,0,0,.6);
+$carousel-text-shadow:                        0 1px 2px rgba(0,0,0,.6) !default;
 
-$carousel-control-color:                      #fff;
-$carousel-control-width:                      15%;
-$carousel-control-opacity:                    .5;
-$carousel-control-font-size:                  20px;
+$carousel-control-color:                      #fff !default;
+$carousel-control-width:                      15% !default;
+$carousel-control-opacity:                    .5 !default;
+$carousel-control-font-size:                  20px !default;
 
-$carousel-indicator-active-bg:                #fff;
-$carousel-indicator-border-color:             #fff;
+$carousel-indicator-active-bg:                #fff !default;
+$carousel-indicator-border-color:             #fff !default;
 
-$carousel-caption-color:                      #fff;
+$carousel-caption-color:                      #fff !default;
 
 
 //== Close
 //
 //##
 
-$close-font-weight:           bold;
-$close-color:                 #fff;
-$close-text-shadow:           0 1px 0 #fff;
+$close-font-weight:           bold !default;
+$close-color:                 #fff !default;
+$close-text-shadow:           0 1px 0 #fff !default;
 
 
 //== Code
 //
 //##
 
-$code-color:                  #c7254e;
-$code-bg:                     #f9f2f4;
+$code-color:                  #c7254e !default;
+$code-bg:                     #f9f2f4 !default;
 
-$kbd-color:                   #fff;
-$kbd-bg:                      #333;
+$kbd-color:                   #fff !default;
+$kbd-bg:                      #333 !default;
 
-$pre-bg:                      #f5f5f5;
-$pre-color:                   $gray-dark;
-$pre-border-color:            #ccc;
-$pre-scrollable-max-height:   340px;
+$pre-bg:                      #f5f5f5 !default;
+$pre-color:                   $gray-dark !default;
+$pre-border-color:            #ccc !default;
+$pre-scrollable-max-height:   340px !default;
 
 
 //== Type
@@ -840,22 +840,22 @@ $pre-scrollable-max-height:   340px;
 //##
 
 //** Horizontal offset for forms and lists.
-$component-offset-horizontal: 180px;
+$component-offset-horizontal: 180px !default;
 //** Text muted color
-$text-muted:                  $gray-light;
+$text-muted:                  $gray-light !default;
 //** Abbreviations and acronyms border color
-$abbr-border-color:           $gray-light;
+$abbr-border-color:           $gray-light !default;
 //** Headings small color
-$headings-small-color:        $gray-light;
+$headings-small-color:        $gray-light !default;
 //** Blockquote small color
-$blockquote-small-color:      $gray-light;
+$blockquote-small-color:      $gray-light !default;
 //** Blockquote font size
-$blockquote-font-size:        ($font-size-base * 1.25);
+$blockquote-font-size:        ($font-size-base * 1.25) !default;
 //** Blockquote border color
-$blockquote-border-color:     $gray-lighter;
+$blockquote-border-color:     $gray-lighter !default;
 //** Page header border color
-$page-header-border-color:    $gray-lighter;
+$page-header-border-color:    $gray-lighter !default;
 //** Width of horizontal description list titles
-$dl-horizontal-offset:        $component-offset-horizontal;
+$dl-horizontal-offset:        $component-offset-horizontal !default;
 //** Horizontal line color.
-$hr-border:                   $gray-lighter;
+$hr-border:                   $gray-lighter !default;
diff --git a/paper/_variables.scss b/paper/_variables.scss
index ce35893b..0e2f3ac6 100644
--- a/paper/_variables.scss
+++ b/paper/_variables.scss
@@ -7,18 +7,18 @@
 //
 //## Gray and brand colors for use across Bootstrap.
 
-$gray-base:              #000;
-$gray-darker:            lighten($gray-base, 13.5%); // #222
-$gray-dark:              #212121;
-$gray:                   #666;
-$gray-light:             #bbb;
-$gray-lighter:           lighten($gray-base, 93.5%); // #eee
+$gray-base:              #000 !default;
+$gray-darker:            lighten($gray-base, 13.5%) !default; // #222
+$gray-dark:              #212121 !default;
+$gray:                   #666 !default;
+$gray-light:             #bbb !default;
+$gray-lighter:           lighten($gray-base, 93.5%) !default; // #eee
 
-$brand-primary:         #2196F3;
-$brand-success:         #4CAF50;
-$brand-info:            #9C27B0;
-$brand-warning:         #ff9800;
-$brand-danger:          #e51c23;
+$brand-primary:         #2196F3 !default;
+$brand-success:         #4CAF50 !default;
+$brand-info:            #9C27B0 !default;
+$brand-warning:         #ff9800 !default;
+$brand-danger:          #e51c23 !default;
 
 
 //== Scaffolding
@@ -26,49 +26,49 @@ $brand-danger:          #e51c23;
 //## Settings for some of the most global styles.
 
 //** Background color for ``.
-$body-bg:               #fff;
+$body-bg:               #fff !default;
 //** Global text color on ``.
-$text-color:            $gray;
+$text-color:            $gray !default;
 
 //** Global textual link color.
-$link-color:            $brand-primary;
+$link-color:            $brand-primary !default;
 //** Link hover color set via `darken()` function.
-$link-hover-color:      darken($link-color, 15%);
+$link-hover-color:      darken($link-color, 15%) !default;
 //** Link hover decoration.
-$link-hover-decoration: underline;
+$link-hover-decoration: underline !default;
 
 
 //== Typography
 //
 //## Font, line-height, and color for body text, headings, and more.
 
-$font-family-sans-serif:  "Roboto", "Helvetica Neue", Helvetica, Arial, sans-serif;
-$font-family-serif:       Georgia, "Times New Roman", Times, serif;
+$font-family-sans-serif:  "Roboto", "Helvetica Neue", Helvetica, Arial, sans-serif !default;
+$font-family-serif:       Georgia, "Times New Roman", Times, serif !default;
 //** Default monospace fonts for ``, ``, and `
`.
-$font-family-monospace:   Menlo, Monaco, Consolas, "Courier New", monospace;
-$font-family-base:        $font-family-sans-serif;
+$font-family-monospace:   Menlo, Monaco, Consolas, "Courier New", monospace !default;
+$font-family-base:        $font-family-sans-serif !default;
 
-$font-size-base:          13px;
-$font-size-large:         ceil(($font-size-base * 1.25)); // ~18px
-$font-size-small:         ceil(($font-size-base * 0.85)); // ~12px
+$font-size-base:          13px !default;
+$font-size-large:         ceil(($font-size-base * 1.25)) !default; // ~18px
+$font-size-small:         ceil(($font-size-base * 0.85)) !default; // ~12px
 
-$font-size-h1:            56px;
-$font-size-h2:            45px;
-$font-size-h3:            34px;
-$font-size-h4:            24px;
-$font-size-h5:            20px;
-$font-size-h6:            14px;
+$font-size-h1:            56px !default;
+$font-size-h2:            45px !default;
+$font-size-h3:            34px !default;
+$font-size-h4:            24px !default;
+$font-size-h5:            20px !default;
+$font-size-h6:            14px !default;
 
 //** Unit-less `line-height` for use in components like buttons.
-$line-height-base:        1.846; // 20/14
+$line-height-base:        1.846 !default; // 20/14
 //** Computed "line-height" (`font-size` * `line-height`) for use with `margin`, `padding`, etc.
-$line-height-computed:    floor(($font-size-base * $line-height-base)); // ~20px
+$line-height-computed:    floor(($font-size-base * $line-height-base)) !default; // ~20px
 
 //** By default, this inherits from the ``.
-$headings-font-family:    inherit;
-$headings-font-weight:    400;
-$headings-line-height:    1.1;
-$headings-color:          #444;
+$headings-font-family:    inherit !default;
+$headings-font-weight:    400 !default;
+$headings-line-height:    1.1 !default;
+$headings-color:          #444 !default;
 
 
 //== Iconography
@@ -76,45 +76,45 @@ $headings-color:          #444;
 //## Specify custom location and filename of the included Glyphicons icon font. Useful for those including Bootstrap via Bower.
 
 //** Load fonts from this directory.
-$icon-font-path:          "../fonts/";
+$icon-font-path:          "../fonts/" !default;
 //** File name for all font files.
-$icon-font-name:          "glyphicons-halflings-regular";
+$icon-font-name:          "glyphicons-halflings-regular" !default;
 //** Element ID within SVG icon file.
-$icon-font-svg-id:        "glyphicons_halflingsregular";
+$icon-font-svg-id:        "glyphicons_halflingsregular" !default;
 
 
 //== Components
 //
 //## Define common padding and border radius sizes and more. Values based on 14px text and 1.428 line-height (~20px to start).
 
-$padding-base-vertical:     6px;
-$padding-base-horizontal:   16px;
+$padding-base-vertical:     6px !default;
+$padding-base-horizontal:   16px !default;
 
-$padding-large-vertical:    10px;
-$padding-large-horizontal:  16px;
+$padding-large-vertical:    10px !default;
+$padding-large-horizontal:  16px !default;
 
-$padding-small-vertical:    5px;
-$padding-small-horizontal:  10px;
+$padding-small-vertical:    5px !default;
+$padding-small-horizontal:  10px !default;
 
-$padding-xs-vertical:       1px;
-$padding-xs-horizontal:     5px;
+$padding-xs-vertical:       1px !default;
+$padding-xs-horizontal:     5px !default;
 
-$line-height-large:         1.3333333; // extra decimals for Win 8.1 Chrome
-$line-height-small:         1.5;
+$line-height-large:         1.3333333 !default; // extra decimals for Win 8.1 Chrome
+$line-height-small:         1.5 !default;
 
-$border-radius-base:        3px;
-$border-radius-large:       3px;
-$border-radius-small:       3px;
+$border-radius-base:        3px !default;
+$border-radius-large:       3px !default;
+$border-radius-small:       3px !default;
 
 //** Global color for active items (e.g., navs or dropdowns).
-$component-active-color:    #fff;
+$component-active-color:    #fff !default;
 //** Global background color for active items (e.g., navs or dropdowns).
-$component-active-bg:       $brand-primary;
+$component-active-bg:       $brand-primary !default;
 
 //** Width of the `border` for generating carets that indicator dropdowns.
-$caret-width-base:          4px;
+$caret-width-base:          4px !default;
 //** Carets increase slightly in size for larger components.
-$caret-width-large:         5px;
+$caret-width-large:         5px !default;
 
 
 //== Tables
@@ -122,53 +122,53 @@ $caret-width-large:         5px;
 //## Customizes the `.table` component with basic values, each used across all table variations.
 
 //** Padding for ``s and ``s.
-$table-cell-padding:            8px;
+$table-cell-padding:            8px !default;
 //** Padding for cells in `.table-condensed`.
-$table-condensed-cell-padding:  5px;
+$table-condensed-cell-padding:  5px !default;
 
 //** Default background color used for all tables.
-$table-bg:                      transparent;
+$table-bg:                      transparent !default;
 //** Background color used for `.table-striped`.
-$table-bg-accent:               #f9f9f9;
+$table-bg-accent:               #f9f9f9 !default;
 //** Background color used for `.table-hover`.
-$table-bg-hover:                #f5f5f5;
-$table-bg-active:               $table-bg-hover;
+$table-bg-hover:                #f5f5f5 !default;
+$table-bg-active:               $table-bg-hover !default;
 
 //** Border color for table and cell borders.
-$table-border-color:            #ddd;
+$table-border-color:            #ddd !default;
 
 
 //== Buttons
 //
 //## For each of Bootstrap's buttons, define text, background and border color.
 
-$btn-font-weight:                normal;
+$btn-font-weight:                normal !default;
 
-$btn-default-color:              $text-color;
-$btn-default-bg:                 #fff;
-$btn-default-border:             #eee;
+$btn-default-color:              $text-color !default;
+$btn-default-bg:                 #fff !default;
+$btn-default-border:             #eee !default;
 
-$btn-primary-color:              #fff;
-$btn-primary-bg:                 $brand-primary;
-$btn-primary-border:             transparent;
+$btn-primary-color:              #fff !default;
+$btn-primary-bg:                 $brand-primary !default;
+$btn-primary-border:             transparent !default;
 
-$btn-success-color:              #fff;
-$btn-success-bg:                 $brand-success;
-$btn-success-border:             transparent;
+$btn-success-color:              #fff !default;
+$btn-success-bg:                 $brand-success !default;
+$btn-success-border:             transparent !default;
 
-$btn-info-color:                 #fff;
-$btn-info-bg:                    $brand-info;
-$btn-info-border:                transparent;
+$btn-info-color:                 #fff !default;
+$btn-info-bg:                    $brand-info !default;
+$btn-info-border:                transparent !default;
 
-$btn-warning-color:              #fff;
-$btn-warning-bg:                 $brand-warning;
-$btn-warning-border:             transparent;
+$btn-warning-color:              #fff !default;
+$btn-warning-bg:                 $brand-warning !default;
+$btn-warning-border:             transparent !default;
 
-$btn-danger-color:               #fff;
-$btn-danger-bg:                  $brand-danger;
-$btn-danger-border:              transparent;
+$btn-danger-color:               #fff !default;
+$btn-danger-bg:                  $brand-danger !default;
+$btn-danger-border:              transparent !default;
 
-$btn-link-disabled-color:        $gray-light;
+$btn-link-disabled-color:        $gray-light !default;
 
 
 //== Forms
@@ -176,50 +176,50 @@ $btn-link-disabled-color:        $gray-light;
 //##
 
 //** `` background color
-$input-bg:                       transparent;
+$input-bg:                       transparent !default;
 //** `` background color
-$input-bg-disabled:              transparent;
+$input-bg-disabled:              transparent !default;
 
 //** Text color for ``s
-$input-color:                    $gray;
+$input-color:                    $gray !default;
 //** `` border color
-$input-border:                   transparent;
+$input-border:                   transparent !default;
 
 // TODO: Rename `$input-border-radius` to `$input-border-radius-base` in v4
 //** Default `.form-control` border radius
 // This has no effect on ``s in CSS.
-$input-border-radius:            $border-radius-base;
+$input-border-radius:            $border-radius-base !default;
 //** Large `.form-control` border radius
-$input-border-radius-large:      $border-radius-large;
+$input-border-radius-large:      $border-radius-large !default;
 //** Small `.form-control` border radius
-$input-border-radius-small:      $border-radius-small;
+$input-border-radius-small:      $border-radius-small !default;
 
 //** Border color for inputs on focus
-$input-border-focus:             #66afe9;
+$input-border-focus:             #66afe9 !default;
 
 //** Placeholder text color
-$input-color-placeholder:        $gray-light;
+$input-color-placeholder:        $gray-light !default;
 
 //** Default `.form-control` height
-$input-height-base:              ($line-height-computed + ($padding-base-vertical * 2) + 2);
+$input-height-base:              ($line-height-computed + ($padding-base-vertical * 2) + 2) !default;
 //** Large `.form-control` height
-$input-height-large:             (ceil($font-size-large * $line-height-large) + ($padding-large-vertical * 2) + 2);
+$input-height-large:             (ceil($font-size-large * $line-height-large) + ($padding-large-vertical * 2) + 2) !default;
 //** Small `.form-control` height
-$input-height-small:             (floor($font-size-small * $line-height-small) + ($padding-small-vertical * 2) + 2);
+$input-height-small:             (floor($font-size-small * $line-height-small) + ($padding-small-vertical * 2) + 2) !default;
 
 //** `.form-group` margin
-$form-group-margin-bottom:       15px;
+$form-group-margin-bottom:       15px !default;
 
-$legend-color:                   $gray-dark;
-$legend-border-color:            #e5e5e5;
+$legend-color:                   $gray-dark !default;
+$legend-border-color:            #e5e5e5 !default;
 
 //** Background color for textual input addons
-$input-group-addon-bg:           transparent;
+$input-group-addon-bg:           transparent !default;
 //** Border color for textual input addons
-$input-group-addon-border-color: $input-border;
+$input-group-addon-border-color: $input-border !default;
 
 //** Disabled cursor for form controls and buttons.
-$cursor-disabled:                not-allowed;
+$cursor-disabled:                not-allowed !default;
 
 
 //== Dropdowns
@@ -227,34 +227,34 @@ $cursor-disabled:                not-allowed;
 //## Dropdown menu container and contents.
 
 //** Background for the dropdown menu.
-$dropdown-bg:                    #fff;
+$dropdown-bg:                    #fff !default;
 //** Dropdown menu `border-color`.
-$dropdown-border:                rgba(0,0,0,.15);
+$dropdown-border:                rgba(0,0,0,.15) !default;
 //** Dropdown menu `border-color` **for IE8**.
-$dropdown-fallback-border:       #ccc;
+$dropdown-fallback-border:       #ccc !default;
 //** Divider color for between dropdown items.
-$dropdown-divider-bg:            #e5e5e5;
+$dropdown-divider-bg:            #e5e5e5 !default;
 
 //** Dropdown link text color.
-$dropdown-link-color:            $text-color;
+$dropdown-link-color:            $text-color !default;
 //** Hover color for dropdown links.
-$dropdown-link-hover-color:      darken($gray-dark, 5%);
+$dropdown-link-hover-color:      darken($gray-dark, 5%) !default;
 //** Hover background for dropdown links.
-$dropdown-link-hover-bg:         $gray-lighter;
+$dropdown-link-hover-bg:         $gray-lighter !default;
 
 //** Active dropdown menu item text color.
-$dropdown-link-active-color:     $component-active-color;
+$dropdown-link-active-color:     $component-active-color !default;
 //** Active dropdown menu item background color.
-$dropdown-link-active-bg:        $component-active-bg;
+$dropdown-link-active-bg:        $component-active-bg !default;
 
 //** Disabled dropdown menu item background color.
-$dropdown-link-disabled-color:   $gray-light;
+$dropdown-link-disabled-color:   $gray-light !default;
 
 //** Text color for headers within dropdown menus.
-$dropdown-header-color:          $gray-light;
+$dropdown-header-color:          $gray-light !default;
 
 //** Deprecated `$dropdown-caret-color` as of v3.1.0
-$dropdown-caret-color:           $gray-light;
+$dropdown-caret-color:           $gray-light !default;
 
 
 //-- Z-index master list
@@ -264,13 +264,13 @@ $dropdown-caret-color:           $gray-light;
 //
 // Note: These variables are not generated into the Customizer.
 
-$zindex-navbar:            1000;
-$zindex-dropdown:          1000;
-$zindex-popover:           1060;
-$zindex-tooltip:           1070;
-$zindex-navbar-fixed:      1030;
-$zindex-modal-background:  1040;
-$zindex-modal:             1050;
+$zindex-navbar:            1000 !default;
+$zindex-dropdown:          1000 !default;
+$zindex-popover:           1060 !default;
+$zindex-tooltip:           1070 !default;
+$zindex-navbar-fixed:      1030 !default;
+$zindex-modal-background:  1040 !default;
+$zindex-modal:             1050 !default;
 
 
 //== Media queries breakpoints
@@ -279,37 +279,37 @@ $zindex-modal:             1050;
 
 // Extra small screen / phone
 //** Deprecated `$screen-xs` as of v3.0.1
-$screen-xs:                  480px;
+$screen-xs:                  480px !default;
 //** Deprecated `$screen-xs-min` as of v3.2.0
-$screen-xs-min:              $screen-xs;
+$screen-xs-min:              $screen-xs !default;
 //** Deprecated `$screen-phone` as of v3.0.1
-$screen-phone:               $screen-xs-min;
+$screen-phone:               $screen-xs-min !default;
 
 // Small screen / tablet
 //** Deprecated `$screen-sm` as of v3.0.1
-$screen-sm:                  768px;
-$screen-sm-min:              $screen-sm;
+$screen-sm:                  768px !default;
+$screen-sm-min:              $screen-sm !default;
 //** Deprecated `$screen-tablet` as of v3.0.1
-$screen-tablet:              $screen-sm-min;
+$screen-tablet:              $screen-sm-min !default;
 
 // Medium screen / desktop
 //** Deprecated `$screen-md` as of v3.0.1
-$screen-md:                  992px;
-$screen-md-min:              $screen-md;
+$screen-md:                  992px !default;
+$screen-md-min:              $screen-md !default;
 //** Deprecated `$screen-desktop` as of v3.0.1
-$screen-desktop:             $screen-md-min;
+$screen-desktop:             $screen-md-min !default;
 
 // Large screen / wide desktop
 //** Deprecated `$screen-lg` as of v3.0.1
-$screen-lg:                  1200px;
-$screen-lg-min:              $screen-lg;
+$screen-lg:                  1200px !default;
+$screen-lg-min:              $screen-lg !default;
 //** Deprecated `$screen-lg-desktop` as of v3.0.1
-$screen-lg-desktop:          $screen-lg-min;
+$screen-lg-desktop:          $screen-lg-min !default;
 
 // So media queries don't overlap when required, provide a maximum
-$screen-xs-max:              ($screen-sm-min - 1);
-$screen-sm-max:              ($screen-md-min - 1);
-$screen-md-max:              ($screen-lg-min - 1);
+$screen-xs-max:              ($screen-sm-min - 1) !default;
+$screen-sm-max:              ($screen-md-min - 1) !default;
+$screen-md-max:              ($screen-lg-min - 1) !default;
 
 
 //== Grid system
@@ -317,14 +317,14 @@ $screen-md-max:              ($screen-lg-min - 1);
 //## Define your custom responsive grid.
 
 //** Number of columns in the grid.
-$grid-columns:              12;
+$grid-columns:              12 !default;
 //** Padding between columns. Gets divided in half for the left and right.
-$grid-gutter-width:         30px;
+$grid-gutter-width:         30px !default;
 // Navbar collapse
 //** Point at which the navbar becomes uncollapsed.
-$grid-float-breakpoint:     $screen-sm-min;
+$grid-float-breakpoint:     $screen-sm-min !default;
 //** Point at which the navbar begins collapsing.
-$grid-float-breakpoint-max: ($grid-float-breakpoint - 1);
+$grid-float-breakpoint-max: ($grid-float-breakpoint - 1) !default;
 
 
 //== Container sizes
@@ -332,19 +332,19 @@ $grid-float-breakpoint-max: ($grid-float-breakpoint - 1);
 //## Define the maximum width of `.container` for different screen sizes.
 
 // Small screen / tablet
-$container-tablet:             (720px + $grid-gutter-width);
+$container-tablet:             (720px + $grid-gutter-width) !default;
 //** For `$screen-sm-min` and up.
-$container-sm:                 $container-tablet;
+$container-sm:                 $container-tablet !default;
 
 // Medium screen / desktop
-$container-desktop:            (940px + $grid-gutter-width);
+$container-desktop:            (940px + $grid-gutter-width) !default;
 //** For `$screen-md-min` and up.
-$container-md:                 $container-desktop;
+$container-md:                 $container-desktop !default;
 
 // Large screen / wide desktop
-$container-large-desktop:      (1140px + $grid-gutter-width);
+$container-large-desktop:      (1140px + $grid-gutter-width) !default;
 //** For `$screen-lg-min` and up.
-$container-lg:                 $container-large-desktop;
+$container-lg:                 $container-large-desktop !default;
 
 
 //== Navbar
@@ -352,61 +352,61 @@ $container-lg:                 $container-large-desktop;
 //##
 
 // Basics of a navbar
-$navbar-height:                    64px;
-$navbar-margin-bottom:             $line-height-computed;
-$navbar-border-radius:             $border-radius-base;
-$navbar-padding-horizontal:        floor(($grid-gutter-width / 2));
-$navbar-padding-vertical:          (($navbar-height - $line-height-computed) / 2);
-$navbar-collapse-max-height:       340px;
+$navbar-height:                    64px !default;
+$navbar-margin-bottom:             $line-height-computed !default;
+$navbar-border-radius:             $border-radius-base !default;
+$navbar-padding-horizontal:        floor(($grid-gutter-width / 2)) !default;
+$navbar-padding-vertical:          (($navbar-height - $line-height-computed) / 2) !default;
+$navbar-collapse-max-height:       340px !default;
 
-$navbar-default-color:             $gray-light;
-$navbar-default-bg:                #fff;
-$navbar-default-border:            transparent;
+$navbar-default-color:             $gray-light !default;
+$navbar-default-bg:                #fff !default;
+$navbar-default-border:            transparent !default;
 
 // Navbar links
-$navbar-default-link-color:                $gray;
-$navbar-default-link-hover-color:          $gray-dark;
-$navbar-default-link-hover-bg:             transparent;
-$navbar-default-link-active-color:         $gray-dark;
-$navbar-default-link-active-bg:            darken($navbar-default-bg, 6.5%);
-$navbar-default-link-disabled-color:       #ccc;
-$navbar-default-link-disabled-bg:          transparent;
+$navbar-default-link-color:                $gray !default;
+$navbar-default-link-hover-color:          $gray-dark !default;
+$navbar-default-link-hover-bg:             transparent !default;
+$navbar-default-link-active-color:         $gray-dark !default;
+$navbar-default-link-active-bg:            darken($navbar-default-bg, 6.5%) !default;
+$navbar-default-link-disabled-color:       #ccc !default;
+$navbar-default-link-disabled-bg:          transparent !default;
 
 // Navbar brand label
-$navbar-default-brand-color:               $navbar-default-link-color;
-$navbar-default-brand-hover-color:         $navbar-default-link-hover-color;
-$navbar-default-brand-hover-bg:            transparent;
+$navbar-default-brand-color:               $navbar-default-link-color !default;
+$navbar-default-brand-hover-color:         $navbar-default-link-hover-color !default;
+$navbar-default-brand-hover-bg:            transparent !default;
 
 // Navbar toggle
-$navbar-default-toggle-hover-bg:           transparent;
-$navbar-default-toggle-icon-bar-bg:        rgba(0,0,0,0.5);
-$navbar-default-toggle-border-color:       transparent;
+$navbar-default-toggle-hover-bg:           transparent !default;
+$navbar-default-toggle-icon-bar-bg:        rgba(0,0,0,0.5) !default;
+$navbar-default-toggle-border-color:       transparent !default;
 
 
 // Inverted navbar
 // Reset inverted navbar basics
-$navbar-inverse-color:                      $gray-light;
-$navbar-inverse-bg:                         $brand-primary;
-$navbar-inverse-border:                     transparent;
+$navbar-inverse-color:                      $gray-light !default;
+$navbar-inverse-bg:                         $brand-primary !default;
+$navbar-inverse-border:                     transparent !default;
 
 // Inverted navbar links
-$navbar-inverse-link-color:                 lighten($brand-primary, 30%);
-$navbar-inverse-link-hover-color:           #fff;
-$navbar-inverse-link-hover-bg:              transparent;
-$navbar-inverse-link-active-color:          $navbar-inverse-link-hover-color;
-$navbar-inverse-link-active-bg:             darken($navbar-inverse-bg, 10%);
-$navbar-inverse-link-disabled-color:        #444;
-$navbar-inverse-link-disabled-bg:           transparent;
+$navbar-inverse-link-color:                 lighten($brand-primary, 30%) !default;
+$navbar-inverse-link-hover-color:           #fff !default;
+$navbar-inverse-link-hover-bg:              transparent !default;
+$navbar-inverse-link-active-color:          $navbar-inverse-link-hover-color !default;
+$navbar-inverse-link-active-bg:             darken($navbar-inverse-bg, 10%) !default;
+$navbar-inverse-link-disabled-color:        #444 !default;
+$navbar-inverse-link-disabled-bg:           transparent !default;
 
 // Inverted navbar brand label
-$navbar-inverse-brand-color:                $navbar-inverse-link-color;
-$navbar-inverse-brand-hover-color:          #fff;
-$navbar-inverse-brand-hover-bg:             transparent;
+$navbar-inverse-brand-color:                $navbar-inverse-link-color !default;
+$navbar-inverse-brand-hover-color:          #fff !default;
+$navbar-inverse-brand-hover-bg:             transparent !default;
 
 // Inverted navbar toggle\
-$navbar-inverse-toggle-hover-bg:            transparent;
-$navbar-inverse-toggle-icon-bar-bg:         rgba(0,0,0,0.5);
-$navbar-inverse-toggle-border-color:        transparent;
+$navbar-inverse-toggle-hover-bg:            transparent !default;
+$navbar-inverse-toggle-icon-bar-bg:         rgba(0,0,0,0.5) !default;
+$navbar-inverse-toggle-border-color:        transparent !default;
 
 
 //== Navs
@@ -414,97 +414,97 @@ $navbar-inverse-toggle-border-color:        transparent;
 //##
 
 //=== Shared nav styles
-$nav-link-padding:                          10px 15px;
-$nav-link-hover-bg:                         $gray-lighter;
+$nav-link-padding:                          10px 15px !default;
+$nav-link-hover-bg:                         $gray-lighter !default;
 
-$nav-disabled-link-color:                   $gray-light;
-$nav-disabled-link-hover-color:             $gray-light;
+$nav-disabled-link-color:                   $gray-light !default;
+$nav-disabled-link-hover-color:             $gray-light !default;
 
 //== Tabs
-$nav-tabs-border-color:                     transparent;
+$nav-tabs-border-color:                     transparent !default;
 
-$nav-tabs-link-hover-border-color:          $gray-lighter;
+$nav-tabs-link-hover-border-color:          $gray-lighter !default;
 
-$nav-tabs-active-link-hover-bg:             transparent;
-$nav-tabs-active-link-hover-color:          $gray;
-$nav-tabs-active-link-hover-border-color:   transparent;
+$nav-tabs-active-link-hover-bg:             transparent !default;
+$nav-tabs-active-link-hover-color:          $gray !default;
+$nav-tabs-active-link-hover-border-color:   transparent !default;
 
-$nav-tabs-justified-link-border-color:            $nav-tabs-border-color;
-$nav-tabs-justified-active-link-border-color:     $body-bg;
+$nav-tabs-justified-link-border-color:            $nav-tabs-border-color !default;
+$nav-tabs-justified-active-link-border-color:     $body-bg !default;
 
 //== Pills
-$nav-pills-border-radius:                   $border-radius-base;
-$nav-pills-active-link-hover-bg:            $component-active-bg;
-$nav-pills-active-link-hover-color:         $component-active-color;
+$nav-pills-border-radius:                   $border-radius-base !default;
+$nav-pills-active-link-hover-bg:            $component-active-bg !default;
+$nav-pills-active-link-hover-color:         $component-active-color !default;
 
 
 //== Pagination
 //
 //##
 
-$pagination-color:                     $link-color;
-$pagination-bg:                        #fff;
-$pagination-border:                    #ddd;
+$pagination-color:                     $link-color !default;
+$pagination-bg:                        #fff !default;
+$pagination-border:                    #ddd !default;
 
-$pagination-hover-color:               $link-hover-color;
-$pagination-hover-bg:                  $gray-lighter;
-$pagination-hover-border:              #ddd;
+$pagination-hover-color:               $link-hover-color !default;
+$pagination-hover-bg:                  $gray-lighter !default;
+$pagination-hover-border:              #ddd !default;
 
-$pagination-active-color:              #fff;
-$pagination-active-bg:                 $brand-primary;
-$pagination-active-border:             $brand-primary;
+$pagination-active-color:              #fff !default;
+$pagination-active-bg:                 $brand-primary !default;
+$pagination-active-border:             $brand-primary !default;
 
-$pagination-disabled-color:            $gray-light;
-$pagination-disabled-bg:               #fff;
-$pagination-disabled-border:           #ddd;
+$pagination-disabled-color:            $gray-light !default;
+$pagination-disabled-bg:               #fff !default;
+$pagination-disabled-border:           #ddd !default;
 
 
 //== Pager
 //
 //##
 
-$pager-bg:                             $pagination-bg;
-$pager-border:                         $pagination-border;
-$pager-border-radius:                  15px;
+$pager-bg:                             $pagination-bg !default;
+$pager-border:                         $pagination-border !default;
+$pager-border-radius:                  15px !default;
 
-$pager-hover-bg:                       $pagination-hover-bg;
+$pager-hover-bg:                       $pagination-hover-bg !default;
 
-$pager-active-bg:                      $pagination-active-bg;
-$pager-active-color:                   $pagination-active-color;
+$pager-active-bg:                      $pagination-active-bg !default;
+$pager-active-color:                   $pagination-active-color !default;
 
-$pager-disabled-color:                 $pagination-disabled-color;
+$pager-disabled-color:                 $pagination-disabled-color !default;
 
 
 //== Jumbotron
 //
 //##
 
-$jumbotron-padding:              30px;
-$jumbotron-color:                inherit;
-$jumbotron-bg:                   #f9f9f9;
-$jumbotron-heading-color:        $headings-color;
-$jumbotron-font-size:            ceil(($font-size-base * 1.5));
+$jumbotron-padding:              30px !default;
+$jumbotron-color:                inherit !default;
+$jumbotron-bg:                   #f9f9f9 !default;
+$jumbotron-heading-color:        $headings-color !default;
+$jumbotron-font-size:            ceil(($font-size-base * 1.5)) !default;
 
 
 //== Form states and alerts
 //
 //## Define colors for form feedback states and, by default, alerts.
 
-$state-success-text:             $brand-success;
-$state-success-bg:               #dff0d8;
-$state-success-border:           darken(adjust-hue($state-success-bg, -10), 5%);
+$state-success-text:             $brand-success !default;
+$state-success-bg:               #dff0d8 !default;
+$state-success-border:           darken(adjust-hue($state-success-bg, -10), 5%) !default;
 
-$state-info-text:                $brand-info;
-$state-info-bg:                  #e1bee7;
-$state-info-border:              darken(adjust-hue($state-info-bg, -10), 7%);
+$state-info-text:                $brand-info !default;
+$state-info-bg:                  #e1bee7 !default;
+$state-info-border:              darken(adjust-hue($state-info-bg, -10), 7%) !default;
 
-$state-warning-text:             $brand-warning;
-$state-warning-bg:               #ffe0b2;
-$state-warning-border:           darken(adjust-hue($state-warning-bg, -10), 5%);
+$state-warning-text:             $brand-warning !default;
+$state-warning-bg:               #ffe0b2 !default;
+$state-warning-border:           darken(adjust-hue($state-warning-bg, -10), 5%) !default;
 
-$state-danger-text:              $brand-danger;
-$state-danger-bg:                #f9bdbb;
-$state-danger-border:            darken(adjust-hue($state-danger-bg, -10), 5%);
+$state-danger-text:              $brand-danger !default;
+$state-danger-bg:                #f9bdbb !default;
+$state-danger-border:            darken(adjust-hue($state-danger-bg, -10), 5%) !default;
 
 
 //== Tooltips
@@ -512,17 +512,17 @@ $state-danger-border:            darken(adjust-hue($state-danger-bg, -10), 5%);
 //##
 
 //** Tooltip max width
-$tooltip-max-width:           200px;
+$tooltip-max-width:           200px !default;
 //** Tooltip text color
-$tooltip-color:               #fff;
+$tooltip-color:               #fff !default;
 //** Tooltip background color
-$tooltip-bg:                  #727272;
-$tooltip-opacity:             .9;
+$tooltip-bg:                  #727272 !default;
+$tooltip-opacity:             .9 !default;
 
 //** Tooltip arrow width
-$tooltip-arrow-width:         5px;
+$tooltip-arrow-width:         5px !default;
 //** Tooltip arrow color
-$tooltip-arrow-color:         $tooltip-bg;
+$tooltip-arrow-color:         $tooltip-bg !default;
 
 
 //== Popovers
@@ -530,28 +530,28 @@ $tooltip-arrow-color:         $tooltip-bg;
 //##
 
 //** Popover body background color
-$popover-bg:                          #fff;
+$popover-bg:                          #fff !default;
 //** Popover maximum width
-$popover-max-width:                   276px;
+$popover-max-width:                   276px !default;
 //** Popover border color
-$popover-border-color:                transparent;
+$popover-border-color:                transparent !default;
 //** Popover fallback border color
-$popover-fallback-border-color:       transparent;
+$popover-fallback-border-color:       transparent !default;
 
 //** Popover title background color
-$popover-title-bg:                    darken($popover-bg, 3%);
+$popover-title-bg:                    darken($popover-bg, 3%) !default;
 
 //** Popover arrow width
-$popover-arrow-width:                 10px;
+$popover-arrow-width:                 10px !default;
 //** Popover arrow color
-$popover-arrow-color:                 $popover-bg;
+$popover-arrow-color:                 $popover-bg !default;
 
 //** Popover outer arrow width
-$popover-arrow-outer-width:           ($popover-arrow-width + 1);
+$popover-arrow-outer-width:           ($popover-arrow-width + 1) !default;
 //** Popover outer arrow color
-$popover-arrow-outer-color:           fadein($popover-border-color, 7.5%);
+$popover-arrow-outer-color:           fadein($popover-border-color, 7.5%) !default;
 //** Popover outer arrow fallback color
-$popover-arrow-outer-fallback-color:  darken($popover-fallback-border-color, 20%);
+$popover-arrow-outer-fallback-color:  darken($popover-fallback-border-color, 20%) !default;
 
 
 //== Labels
@@ -559,22 +559,22 @@ $popover-arrow-outer-fallback-color:  darken($popover-fallback-border-color, 20%
 //##
 
 //** Default label background color
-$label-default-bg:            $gray-light;
+$label-default-bg:            $gray-light !default;
 //** Primary label background color
-$label-primary-bg:            $brand-primary;
+$label-primary-bg:            $brand-primary !default;
 //** Success label background color
-$label-success-bg:            $brand-success;
+$label-success-bg:            $brand-success !default;
 //** Info label background color
-$label-info-bg:               $brand-info;
+$label-info-bg:               $brand-info !default;
 //** Warning label background color
-$label-warning-bg:            $brand-warning;
+$label-warning-bg:            $brand-warning !default;
 //** Danger label background color
-$label-danger-bg:             $brand-danger;
+$label-danger-bg:             $brand-danger !default;
 
 //** Default label text color
-$label-color:                 #fff;
+$label-color:                 #fff !default;
 //** Default text color of a linked label
-$label-link-hover-color:      #fff;
+$label-link-hover-color:      #fff !default;
 
 
 //== Modals
@@ -582,57 +582,57 @@ $label-link-hover-color:      #fff;
 //##
 
 //** Padding applied to the modal body
-$modal-inner-padding:         15px;
+$modal-inner-padding:         15px !default;
 
 //** Padding applied to the modal title
-$modal-title-padding:         15px;
+$modal-title-padding:         15px !default;
 //** Modal title line-height
-$modal-title-line-height:     $line-height-base;
+$modal-title-line-height:     $line-height-base !default;
 
 //** Background color of modal content area
-$modal-content-bg:                             #fff;
+$modal-content-bg:                             #fff !default;
 //** Modal content border color
-$modal-content-border-color:                   transparent;
+$modal-content-border-color:                   transparent !default;
 //** Modal content border color **for IE8**
-$modal-content-fallback-border-color:          #999;
+$modal-content-fallback-border-color:          #999 !default;
 
 //** Modal backdrop background color
-$modal-backdrop-bg:           #000;
+$modal-backdrop-bg:           #000 !default;
 //** Modal backdrop opacity
-$modal-backdrop-opacity:      .5;
+$modal-backdrop-opacity:      .5 !default;
 //** Modal header border color
-$modal-header-border-color:   transparent;
+$modal-header-border-color:   transparent !default;
 //** Modal footer border color
-$modal-footer-border-color:   $modal-header-border-color;
+$modal-footer-border-color:   $modal-header-border-color !default;
 
-$modal-lg:                    900px;
-$modal-md:                    600px;
-$modal-sm:                    300px;
+$modal-lg:                    900px !default;
+$modal-md:                    600px !default;
+$modal-sm:                    300px !default;
 
 
 //== Alerts
 //
 //## Define alert colors, border radius, and padding.
 
-$alert-padding:               15px;
-$alert-border-radius:         $border-radius-base;
-$alert-link-font-weight:      bold;
+$alert-padding:               15px !default;
+$alert-border-radius:         $border-radius-base !default;
+$alert-link-font-weight:      bold !default;
 
-$alert-success-bg:            $state-success-bg;
-$alert-success-text:          $state-success-text;
-$alert-success-border:        $state-success-border;
+$alert-success-bg:            $state-success-bg !default;
+$alert-success-text:          $state-success-text !default;
+$alert-success-border:        $state-success-border !default;
 
-$alert-info-bg:               $state-info-bg;
-$alert-info-text:             $state-info-text;
-$alert-info-border:           $state-info-border;
+$alert-info-bg:               $state-info-bg !default;
+$alert-info-text:             $state-info-text !default;
+$alert-info-border:           $state-info-border !default;
 
-$alert-warning-bg:            $state-warning-bg;
-$alert-warning-text:          $state-warning-text;
-$alert-warning-border:        $state-warning-border;
+$alert-warning-bg:            $state-warning-bg !default;
+$alert-warning-text:          $state-warning-text !default;
+$alert-warning-border:        $state-warning-border !default;
 
-$alert-danger-bg:             $state-danger-bg;
-$alert-danger-text:           $state-danger-text;
-$alert-danger-border:         $state-danger-border;
+$alert-danger-bg:             $state-danger-bg !default;
+$alert-danger-text:           $state-danger-text !default;
+$alert-danger-border:         $state-danger-border !default;
 
 
 //== Progress bars
@@ -640,22 +640,22 @@ $alert-danger-border:         $state-danger-border;
 //##
 
 //** Background color of the whole progress component
-$progress-bg:                 #f5f5f5;
+$progress-bg:                 #f5f5f5 !default;
 //** Progress bar text color
-$progress-bar-color:          #fff;
+$progress-bar-color:          #fff !default;
 //** Variable for setting rounded corners on progress bar.
-$progress-border-radius:      $border-radius-base;
+$progress-border-radius:      $border-radius-base !default;
 
 //** Default progress bar color
-$progress-bar-bg:             $brand-primary;
+$progress-bar-bg:             $brand-primary !default;
 //** Success progress bar color
-$progress-bar-success-bg:     $brand-success;
+$progress-bar-success-bg:     $brand-success !default;
 //** Warning progress bar color
-$progress-bar-warning-bg:     $brand-warning;
+$progress-bar-warning-bg:     $brand-warning !default;
 //** Danger progress bar color
-$progress-bar-danger-bg:      $brand-danger;
+$progress-bar-danger-bg:      $brand-danger !default;
 //** Info progress bar color
-$progress-bar-info-bg:        $brand-info;
+$progress-bar-info-bg:        $brand-info !default;
 
 
 //== List group
@@ -663,72 +663,72 @@ $progress-bar-info-bg:        $brand-info;
 //##
 
 //** Background color on `.list-group-item`
-$list-group-bg:                 #fff;
+$list-group-bg:                 #fff !default;
 //** `.list-group-item` border color
-$list-group-border:             #ddd;
+$list-group-border:             #ddd !default;
 //** List group border radius
-$list-group-border-radius:      $border-radius-base;
+$list-group-border-radius:      $border-radius-base !default;
 
 //** Background color of single list items on hover
-$list-group-hover-bg:           #f5f5f5;
+$list-group-hover-bg:           #f5f5f5 !default;
 //** Text color of active list items
-$list-group-active-color:       $component-active-color;
+$list-group-active-color:       $component-active-color !default;
 //** Background color of active list items
-$list-group-active-bg:          $component-active-bg;
+$list-group-active-bg:          $component-active-bg !default;
 //** Border color of active list elements
-$list-group-active-border:      $list-group-active-bg;
+$list-group-active-border:      $list-group-active-bg !default;
 //** Text color for content within active list items
-$list-group-active-text-color:  lighten($list-group-active-bg, 40%);
+$list-group-active-text-color:  lighten($list-group-active-bg, 40%) !default;
 
 //** Text color of disabled list items
-$list-group-disabled-color:      $gray-light;
+$list-group-disabled-color:      $gray-light !default;
 //** Background color of disabled list items
-$list-group-disabled-bg:         $gray-lighter;
+$list-group-disabled-bg:         $gray-lighter !default;
 //** Text color for content within disabled list items
-$list-group-disabled-text-color: $list-group-disabled-color;
+$list-group-disabled-text-color: $list-group-disabled-color !default;
 
-$list-group-link-color:         #555;
-$list-group-link-hover-color:   $list-group-link-color;
-$list-group-link-heading-color: #333;
+$list-group-link-color:         #555 !default;
+$list-group-link-hover-color:   $list-group-link-color !default;
+$list-group-link-heading-color: #333 !default;
 
 
 //== Panels
 //
 //##
 
-$panel-bg:                    #fff;
-$panel-body-padding:          15px;
-$panel-heading-padding:       10px 15px;
-$panel-footer-padding:        $panel-heading-padding;
-$panel-border-radius:         $border-radius-base;
+$panel-bg:                    #fff !default;
+$panel-body-padding:          15px !default;
+$panel-heading-padding:       10px 15px !default;
+$panel-footer-padding:        $panel-heading-padding !default;
+$panel-border-radius:         $border-radius-base !default;
 
 //** Border color for elements within panels
-$panel-inner-border:          #ddd;
-$panel-footer-bg:             #f5f5f5;
+$panel-inner-border:          #ddd !default;
+$panel-footer-bg:             #f5f5f5 !default;
 
-$panel-default-text:          $gray-dark;
-$panel-default-border:        #ddd;
-$panel-default-heading-bg:    #f5f5f5;
+$panel-default-text:          $gray-dark !default;
+$panel-default-border:        #ddd !default;
+$panel-default-heading-bg:    #f5f5f5 !default;
 
-$panel-primary-text:          #fff;
-$panel-primary-border:        $brand-primary;
-$panel-primary-heading-bg:    $brand-primary;
+$panel-primary-text:          #fff !default;
+$panel-primary-border:        $brand-primary !default;
+$panel-primary-heading-bg:    $brand-primary !default;
 
-$panel-success-text:          #fff;
-$panel-success-border:        $state-success-border;
-$panel-success-heading-bg:    $brand-success;
+$panel-success-text:          #fff !default;
+$panel-success-border:        $state-success-border !default;
+$panel-success-heading-bg:    $brand-success !default;
 
-$panel-info-text:             #fff;
-$panel-info-border:           $state-info-border;
-$panel-info-heading-bg:       $brand-info;
+$panel-info-text:             #fff !default;
+$panel-info-border:           $state-info-border !default;
+$panel-info-heading-bg:       $brand-info !default;
 
-$panel-warning-text:          #fff;
-$panel-warning-border:        $state-warning-border;
-$panel-warning-heading-bg:    $brand-warning;
+$panel-warning-text:          #fff !default;
+$panel-warning-border:        $state-warning-border !default;
+$panel-warning-heading-bg:    $brand-warning !default;
 
-$panel-danger-text:           #fff;
-$panel-danger-border:         $state-danger-border;
-$panel-danger-heading-bg:     $brand-danger;
+$panel-danger-text:           #fff !default;
+$panel-danger-border:         $state-danger-border !default;
+$panel-danger-heading-bg:     $brand-danger !default;
 
 
 //== Thumbnails
@@ -736,103 +736,103 @@ $panel-danger-heading-bg:     $brand-danger;
 //##
 
 //** Padding around the thumbnail image
-$thumbnail-padding:           4px;
+$thumbnail-padding:           4px !default;
 //** Thumbnail background color
-$thumbnail-bg:                $body-bg;
+$thumbnail-bg:                $body-bg !default;
 //** Thumbnail border color
-$thumbnail-border:            #ddd;
+$thumbnail-border:            #ddd !default;
 //** Thumbnail border radius
-$thumbnail-border-radius:     $border-radius-base;
+$thumbnail-border-radius:     $border-radius-base !default;
 
 //** Custom text color for thumbnail captions
-$thumbnail-caption-color:     $text-color;
+$thumbnail-caption-color:     $text-color !default;
 //** Padding around the thumbnail caption
-$thumbnail-caption-padding:   9px;
+$thumbnail-caption-padding:   9px !default;
 
 
 //== Wells
 //
 //##
 
-$well-bg:                     #f9f9f9;
-$well-border:                 transparent;
+$well-bg:                     #f9f9f9 !default;
+$well-border:                 transparent !default;
 
 
 //== Badges
 //
 //##
 
-$badge-color:                 #fff;
+$badge-color:                 #fff !default;
 //** Linked badge text color on hover
-$badge-link-hover-color:      #fff;
-$badge-bg:                    $gray-light;
+$badge-link-hover-color:      #fff !default;
+$badge-bg:                    $gray-light !default;
 
 //** Badge text color in active nav link
-$badge-active-color:          $link-color;
+$badge-active-color:          $link-color !default;
 //** Badge background color in active nav link
-$badge-active-bg:             #fff;
+$badge-active-bg:             #fff !default;
 
-$badge-font-weight:           normal;
-$badge-line-height:           1;
-$badge-border-radius:         10px;
+$badge-font-weight:           normal !default;
+$badge-line-height:           1 !default;
+$badge-border-radius:         10px !default;
 
 
 //== Breadcrumbs
 //
 //##
 
-$breadcrumb-padding-vertical:   8px;
-$breadcrumb-padding-horizontal: 15px;
+$breadcrumb-padding-vertical:   8px !default;
+$breadcrumb-padding-horizontal: 15px !default;
 //** Breadcrumb background color
-$breadcrumb-bg:                 #f5f5f5;
+$breadcrumb-bg:                 #f5f5f5 !default;
 //** Breadcrumb text color
-$breadcrumb-color:              #ccc;
+$breadcrumb-color:              #ccc !default;
 //** Text color of current page in the breadcrumb
-$breadcrumb-active-color:       $gray-light;
+$breadcrumb-active-color:       $gray-light !default;
 //** Textual separator for between breadcrumb elements
-$breadcrumb-separator:          "/";
+$breadcrumb-separator:          "/" !default;
 
 
 //== Carousel
 //
 //##
 
-$carousel-text-shadow:                        0 1px 2px rgba(0,0,0,.6);
+$carousel-text-shadow:                        0 1px 2px rgba(0,0,0,.6) !default;
 
-$carousel-control-color:                      #fff;
-$carousel-control-width:                      15%;
-$carousel-control-opacity:                    .5;
-$carousel-control-font-size:                  20px;
+$carousel-control-color:                      #fff !default;
+$carousel-control-width:                      15% !default;
+$carousel-control-opacity:                    .5 !default;
+$carousel-control-font-size:                  20px !default;
 
-$carousel-indicator-active-bg:                #fff;
-$carousel-indicator-border-color:             #fff;
+$carousel-indicator-active-bg:                #fff !default;
+$carousel-indicator-border-color:             #fff !default;
 
-$carousel-caption-color:                      #fff;
+$carousel-caption-color:                      #fff !default;
 
 
 //== Close
 //
 //##
 
-$close-font-weight:           normal;
-$close-color:                 #000;
-$close-text-shadow:           none;
+$close-font-weight:           normal !default;
+$close-color:                 #000 !default;
+$close-text-shadow:           none !default;
 
 
 //== Code
 //
 //##
 
-$code-color:                  #c7254e;
-$code-bg:                     #f9f2f4;
+$code-color:                  #c7254e !default;
+$code-bg:                     #f9f2f4 !default;
 
-$kbd-color:                   #fff;
-$kbd-bg:                      #333;
+$kbd-color:                   #fff !default;
+$kbd-bg:                      #333 !default;
 
-$pre-bg:                      #f5f5f5;
-$pre-color:                   $gray-dark;
-$pre-border-color:            #ccc;
-$pre-scrollable-max-height:   340px;
+$pre-bg:                      #f5f5f5 !default;
+$pre-color:                   $gray-dark !default;
+$pre-border-color:            #ccc !default;
+$pre-scrollable-max-height:   340px !default;
 
 
 //== Type
@@ -840,22 +840,22 @@ $pre-scrollable-max-height:   340px;
 //##
 
 //** Horizontal offset for forms and lists.
-$component-offset-horizontal: 180px;
+$component-offset-horizontal: 180px !default;
 //** Text muted color
-$text-muted:                  $gray-light;
+$text-muted:                  $gray-light !default;
 //** Abbreviations and acronyms border color
-$abbr-border-color:           $gray-light;
+$abbr-border-color:           $gray-light !default;
 //** Headings small color
-$headings-small-color:        $gray-light;
+$headings-small-color:        $gray-light !default;
 //** Blockquote small color
-$blockquote-small-color:      $gray-light;
+$blockquote-small-color:      $gray-light !default;
 //** Blockquote font size
-$blockquote-font-size:        ($font-size-base * 1.25);
+$blockquote-font-size:        ($font-size-base * 1.25) !default;
 //** Blockquote border color
-$blockquote-border-color:     $gray-lighter;
+$blockquote-border-color:     $gray-lighter !default;
 //** Page header border color
-$page-header-border-color:    $gray-lighter;
+$page-header-border-color:    $gray-lighter !default;
 //** Width of horizontal description list titles
-$dl-horizontal-offset:        $component-offset-horizontal;
+$dl-horizontal-offset:        $component-offset-horizontal !default;
 //** Horizontal line color.
-$hr-border:                   $gray-lighter;
+$hr-border:                   $gray-lighter !default;
diff --git a/readable/_variables.scss b/readable/_variables.scss
index ec22da3a..8741343d 100644
--- a/readable/_variables.scss
+++ b/readable/_variables.scss
@@ -7,18 +7,18 @@
 //
 //## Gray and brand colors for use across Bootstrap.
 
-$gray-base:              #000;
-$gray-darker:            lighten($gray-base, 13.5%); // #222
-$gray-dark:              lighten($gray-base, 20%);   // #333
-$gray:                   lighten($gray-base, 33.5%); // #555
-$gray-light:             lighten($gray-base, 70%);   // #999
-$gray-lighter:           lighten($gray-base, 93.5%); // #eee
+$gray-base:              #000 !default;
+$gray-darker:            lighten($gray-base, 13.5%) !default; // #222
+$gray-dark:              lighten($gray-base, 20%) !default;   // #333
+$gray:                   lighten($gray-base, 33.5%) !default; // #555
+$gray-light:             lighten($gray-base, 70%) !default;   // #999
+$gray-lighter:           lighten($gray-base, 93.5%) !default; // #eee
 
-$brand-primary:         #4582EC;
-$brand-success:         #3FAD46;
-$brand-info:            #5bc0de;
-$brand-warning:         #f0ad4e;
-$brand-danger:          #d9534f;
+$brand-primary:         #4582EC !default;
+$brand-success:         #3FAD46 !default;
+$brand-info:            #5bc0de !default;
+$brand-warning:         #f0ad4e !default;
+$brand-danger:          #d9534f !default;
 
 
 //== Scaffolding
@@ -26,49 +26,49 @@ $brand-danger:          #d9534f;
 //## Settings for some of the most global styles.
 
 //** Background color for ``.
-$body-bg:               #fff;
+$body-bg:               #fff !default;
 //** Global text color on ``.
-$text-color:            $gray-dark;
+$text-color:            $gray-dark !default;
 
 //** Global textual link color.
-$link-color:            $brand-primary;
+$link-color:            $brand-primary !default;
 //** Link hover color set via `darken()` function.
-$link-hover-color:      darken($link-color, 20%);
+$link-hover-color:      darken($link-color, 20%) !default;
 //** Link hover decoration.
-$link-hover-decoration: underline;
+$link-hover-decoration: underline !default;
 
 
 //== Typography
 //
 //## Font, line-height, and color for body text, headings, and more.
 
-$font-family-sans-serif:  "Raleway", "Helvetica Neue", Helvetica, Arial, sans-serif;
-$font-family-serif:       Georgia, "Times New Roman", Times, serif;
+$font-family-sans-serif:  "Raleway", "Helvetica Neue", Helvetica, Arial, sans-serif !default;
+$font-family-serif:       Georgia, "Times New Roman", Times, serif !default;
 //** Default monospace fonts for ``, ``, and `
`.
-$font-family-monospace:   Menlo, Monaco, Consolas, "Courier New", monospace;
-$font-family-base:        $font-family-serif;
+$font-family-monospace:   Menlo, Monaco, Consolas, "Courier New", monospace !default;
+$font-family-base:        $font-family-serif !default;
 
-$font-size-base:          16px;
-$font-size-large:         ceil(($font-size-base * 1.25)); // ~18px
-$font-size-small:         ceil(($font-size-base * 0.85)); // ~12px
+$font-size-base:          16px !default;
+$font-size-large:         ceil(($font-size-base * 1.25)) !default; // ~18px
+$font-size-small:         ceil(($font-size-base * 0.85)) !default; // ~12px
 
-$font-size-h1:            floor(($font-size-base * 2.6)); // ~36px
-$font-size-h2:            floor(($font-size-base * 2.15)); // ~30px
-$font-size-h3:            ceil(($font-size-base * 1.7)); // ~24px
-$font-size-h4:            ceil(($font-size-base * 1.25)); // ~18px
-$font-size-h5:            $font-size-base;
-$font-size-h6:            ceil(($font-size-base * 0.85)); // ~12px
+$font-size-h1:            floor(($font-size-base * 2.6)) !default; // ~36px
+$font-size-h2:            floor(($font-size-base * 2.15)) !default; // ~30px
+$font-size-h3:            ceil(($font-size-base * 1.7)) !default; // ~24px
+$font-size-h4:            ceil(($font-size-base * 1.25)) !default; // ~18px
+$font-size-h5:            $font-size-base !default;
+$font-size-h6:            ceil(($font-size-base * 0.85)) !default; // ~12px
 
 //** Unit-less `line-height` for use in components like buttons.
-$line-height-base:        1.428571429; // 20/14
+$line-height-base:        1.428571429 !default; // 20/14
 //** Computed "line-height" (`font-size` * `line-height`) for use with `margin`, `padding`, etc.
-$line-height-computed:    floor(($font-size-base * $line-height-base)); // ~20px
+$line-height-computed:    floor(($font-size-base * $line-height-base)) !default; // ~20px
 
 //** By default, this inherits from the ``.
-$headings-font-family:    $font-family-sans-serif;
-$headings-font-weight:    bold;
-$headings-line-height:    1.1;
-$headings-color:          inherit;
+$headings-font-family:    $font-family-sans-serif !default;
+$headings-font-weight:    bold !default;
+$headings-line-height:    1.1 !default;
+$headings-color:          inherit !default;
 
 
 //== Iconography
@@ -76,45 +76,45 @@ $headings-color:          inherit;
 //## Specify custom location and filename of the included Glyphicons icon font. Useful for those including Bootstrap via Bower.
 
 //** Load fonts from this directory.
-$icon-font-path:          "../fonts/";
+$icon-font-path:          "../fonts/" !default;
 //** File name for all font files.
-$icon-font-name:          "glyphicons-halflings-regular";
+$icon-font-name:          "glyphicons-halflings-regular" !default;
 //** Element ID within SVG icon file.
-$icon-font-svg-id:        "glyphicons_halflingsregular";
+$icon-font-svg-id:        "glyphicons_halflingsregular" !default;
 
 
 //== Components
 //
 //## Define common padding and border radius sizes and more. Values based on 14px text and 1.428 line-height (~20px to start).
 
-$padding-base-vertical:     8px;
-$padding-base-horizontal:   12px;
+$padding-base-vertical:     8px !default;
+$padding-base-horizontal:   12px !default;
 
-$padding-large-vertical:    14px;
-$padding-large-horizontal:  16px;
+$padding-large-vertical:    14px !default;
+$padding-large-horizontal:  16px !default;
 
-$padding-small-vertical:    5px;
-$padding-small-horizontal:  10px;
+$padding-small-vertical:    5px !default;
+$padding-small-horizontal:  10px !default;
 
-$padding-xs-vertical:       1px;
-$padding-xs-horizontal:     5px;
+$padding-xs-vertical:       1px !default;
+$padding-xs-horizontal:     5px !default;
 
-$line-height-large:         1.3333333; // extra decimals for Win 8.1 Chrome
-$line-height-small:         1.5;
+$line-height-large:         1.3333333 !default; // extra decimals for Win 8.1 Chrome
+$line-height-small:         1.5 !default;
 
-$border-radius-base:        4px;
-$border-radius-large:       6px;
-$border-radius-small:       3px;
+$border-radius-base:        4px !default;
+$border-radius-large:       6px !default;
+$border-radius-small:       3px !default;
 
 //** Global color for active items (e.g., navs or dropdowns).
-$component-active-color:    #fff;
+$component-active-color:    #fff !default;
 //** Global background color for active items (e.g., navs or dropdowns).
-$component-active-bg:       $brand-primary;
+$component-active-bg:       $brand-primary !default;
 
 //** Width of the `border` for generating carets that indicator dropdowns.
-$caret-width-base:          4px;
+$caret-width-base:          4px !default;
 //** Carets increase slightly in size for larger components.
-$caret-width-large:         5px;
+$caret-width-large:         5px !default;
 
 
 //== Tables
@@ -122,53 +122,53 @@ $caret-width-large:         5px;
 //## Customizes the `.table` component with basic values, each used across all table variations.
 
 //** Padding for ``s and ``s.
-$table-cell-padding:            8px;
+$table-cell-padding:            8px !default;
 //** Padding for cells in `.table-condensed`.
-$table-condensed-cell-padding:  5px;
+$table-condensed-cell-padding:  5px !default;
 
 //** Default background color used for all tables.
-$table-bg:                      transparent;
+$table-bg:                      transparent !default;
 //** Background color used for `.table-striped`.
-$table-bg-accent:               #f9f9f9;
+$table-bg-accent:               #f9f9f9 !default;
 //** Background color used for `.table-hover`.
-$table-bg-hover:                #f5f5f5;
-$table-bg-active:               $table-bg-hover;
+$table-bg-hover:                #f5f5f5 !default;
+$table-bg-active:               $table-bg-hover !default;
 
 //** Border color for table and cell borders.
-$table-border-color:            #ddd;
+$table-border-color:            #ddd !default;
 
 
 //== Buttons
 //
 //## For each of Bootstrap's buttons, define text, background and border color.
 
-$btn-font-weight:                normal;
+$btn-font-weight:                normal !default;
 
-$btn-default-color:              $text-color;
-$btn-default-bg:                 #fff;
-$btn-default-border:             #ddd;
+$btn-default-color:              $text-color !default;
+$btn-default-bg:                 #fff !default;
+$btn-default-border:             #ddd !default;
 
-$btn-primary-color:              #fff;
-$btn-primary-bg:                 $brand-primary;
-$btn-primary-border:             $btn-primary-bg;
+$btn-primary-color:              #fff !default;
+$btn-primary-bg:                 $brand-primary !default;
+$btn-primary-border:             $btn-primary-bg !default;
 
-$btn-success-color:              #fff;
-$btn-success-bg:                 $brand-success;
-$btn-success-border:             $btn-success-bg;
+$btn-success-color:              #fff !default;
+$btn-success-bg:                 $brand-success !default;
+$btn-success-border:             $btn-success-bg !default;
 
-$btn-info-color:                 #fff;
-$btn-info-bg:                    $brand-info;
-$btn-info-border:                $btn-info-bg;
+$btn-info-color:                 #fff !default;
+$btn-info-bg:                    $brand-info !default;
+$btn-info-border:                $btn-info-bg !default;
 
-$btn-warning-color:              #fff;
-$btn-warning-bg:                 $brand-warning;
-$btn-warning-border:             $btn-warning-bg;
+$btn-warning-color:              #fff !default;
+$btn-warning-bg:                 $brand-warning !default;
+$btn-warning-border:             $btn-warning-bg !default;
 
-$btn-danger-color:               #fff;
-$btn-danger-bg:                  $brand-danger;
-$btn-danger-border:              $btn-danger-bg;
+$btn-danger-color:               #fff !default;
+$btn-danger-bg:                  $brand-danger !default;
+$btn-danger-border:              $btn-danger-bg !default;
 
-$btn-link-disabled-color:        $gray-light;
+$btn-link-disabled-color:        $gray-light !default;
 
 
 //== Forms
@@ -176,50 +176,50 @@ $btn-link-disabled-color:        $gray-light;
 //##
 
 //** `` background color
-$input-bg:                       #fff;
+$input-bg:                       #fff !default;
 //** `` background color
-$input-bg-disabled:              $gray-lighter;
+$input-bg-disabled:              $gray-lighter !default;
 
 //** Text color for ``s
-$input-color:                    $text-color;
+$input-color:                    $text-color !default;
 //** `` border color
-$input-border:                   #ddd;
+$input-border:                   #ddd !default;
 
 // TODO: Rename `$input-border-radius` to `$input-border-radius-base` in v4
 //** Default `.form-control` border radius
 // This has no effect on ``s in CSS.
-$input-border-radius:            $border-radius-base;
+$input-border-radius:            $border-radius-base !default;
 //** Large `.form-control` border radius
-$input-border-radius-large:      $border-radius-large;
+$input-border-radius-large:      $border-radius-large !default;
 //** Small `.form-control` border radius
-$input-border-radius-small:      $border-radius-small;
+$input-border-radius-small:      $border-radius-small !default;
 
 //** Border color for inputs on focus
-$input-border-focus:             #66afe9;
+$input-border-focus:             #66afe9 !default;
 
 //** Placeholder text color
-$input-color-placeholder:        $gray-light;
+$input-color-placeholder:        $gray-light !default;
 
 //** Default `.form-control` height
-$input-height-base:              ($line-height-computed + ($padding-base-vertical * 2) + 2);
+$input-height-base:              ($line-height-computed + ($padding-base-vertical * 2) + 2) !default;
 //** Large `.form-control` height
-$input-height-large:             (ceil($font-size-large * $line-height-large) + ($padding-large-vertical * 2) + 2);
+$input-height-large:             (ceil($font-size-large * $line-height-large) + ($padding-large-vertical * 2) + 2) !default;
 //** Small `.form-control` height
-$input-height-small:             (floor($font-size-small * $line-height-small) + ($padding-small-vertical * 2) + 2);
+$input-height-small:             (floor($font-size-small * $line-height-small) + ($padding-small-vertical * 2) + 2) !default;
 
 //** `.form-group` margin
-$form-group-margin-bottom:       15px;
+$form-group-margin-bottom:       15px !default;
 
-$legend-color:                   $text-color;
-$legend-border-color:            #e5e5e5;
+$legend-color:                   $text-color !default;
+$legend-border-color:            #e5e5e5 !default;
 
 //** Background color for textual input addons
-$input-group-addon-bg:           $gray-lighter;
+$input-group-addon-bg:           $gray-lighter !default;
 //** Border color for textual input addons
-$input-group-addon-border-color: $input-border;
+$input-group-addon-border-color: $input-border !default;
 
 //** Disabled cursor for form controls and buttons.
-$cursor-disabled:                not-allowed;
+$cursor-disabled:                not-allowed !default;
 
 
 //== Dropdowns
@@ -227,34 +227,34 @@ $cursor-disabled:                not-allowed;
 //## Dropdown menu container and contents.
 
 //** Background for the dropdown menu.
-$dropdown-bg:                    #fff;
+$dropdown-bg:                    #fff !default;
 //** Dropdown menu `border-color`.
-$dropdown-border:                rgba(0,0,0,.15);
+$dropdown-border:                rgba(0,0,0,.15) !default;
 //** Dropdown menu `border-color` **for IE8**.
-$dropdown-fallback-border:       #ccc;
+$dropdown-fallback-border:       #ccc !default;
 //** Divider color for between dropdown items.
-$dropdown-divider-bg:            #e5e5e5;
+$dropdown-divider-bg:            #e5e5e5 !default;
 
 //** Dropdown link text color.
-$dropdown-link-color:            $gray-dark;
+$dropdown-link-color:            $gray-dark !default;
 //** Hover color for dropdown links.
-$dropdown-link-hover-color:      #fff;
+$dropdown-link-hover-color:      #fff !default;
 //** Hover background for dropdown links.
-$dropdown-link-hover-bg:         $component-active-bg;
+$dropdown-link-hover-bg:         $component-active-bg !default;
 
 //** Active dropdown menu item text color.
-$dropdown-link-active-color:     #fff;
+$dropdown-link-active-color:     #fff !default;
 //** Active dropdown menu item background color.
-$dropdown-link-active-bg:        $component-active-bg;
+$dropdown-link-active-bg:        $component-active-bg !default;
 
 //** Disabled dropdown menu item background color.
-$dropdown-link-disabled-color:   $gray-light;
+$dropdown-link-disabled-color:   $gray-light !default;
 
 //** Text color for headers within dropdown menus.
-$dropdown-header-color:          $gray-light;
+$dropdown-header-color:          $gray-light !default;
 
 //** Deprecated `$dropdown-caret-color` as of v3.1.0
-$dropdown-caret-color:           #000;
+$dropdown-caret-color:           #000 !default;
 
 
 //-- Z-index master list
@@ -264,13 +264,13 @@ $dropdown-caret-color:           #000;
 //
 // Note: These variables are not generated into the Customizer.
 
-$zindex-navbar:            1000;
-$zindex-dropdown:          1000;
-$zindex-popover:           1060;
-$zindex-tooltip:           1070;
-$zindex-navbar-fixed:      1030;
-$zindex-modal-background:  1040;
-$zindex-modal:             1050;
+$zindex-navbar:            1000 !default;
+$zindex-dropdown:          1000 !default;
+$zindex-popover:           1060 !default;
+$zindex-tooltip:           1070 !default;
+$zindex-navbar-fixed:      1030 !default;
+$zindex-modal-background:  1040 !default;
+$zindex-modal:             1050 !default;
 
 
 //== Media queries breakpoints
@@ -279,37 +279,37 @@ $zindex-modal:             1050;
 
 // Extra small screen / phone
 //** Deprecated `$screen-xs` as of v3.0.1
-$screen-xs:                  480px;
+$screen-xs:                  480px !default;
 //** Deprecated `$screen-xs-min` as of v3.2.0
-$screen-xs-min:              $screen-xs;
+$screen-xs-min:              $screen-xs !default;
 //** Deprecated `$screen-phone` as of v3.0.1
-$screen-phone:               $screen-xs-min;
+$screen-phone:               $screen-xs-min !default;
 
 // Small screen / tablet
 //** Deprecated `$screen-sm` as of v3.0.1
-$screen-sm:                  768px;
-$screen-sm-min:              $screen-sm;
+$screen-sm:                  768px !default;
+$screen-sm-min:              $screen-sm !default;
 //** Deprecated `$screen-tablet` as of v3.0.1
-$screen-tablet:              $screen-sm-min;
+$screen-tablet:              $screen-sm-min !default;
 
 // Medium screen / desktop
 //** Deprecated `$screen-md` as of v3.0.1
-$screen-md:                  992px;
-$screen-md-min:              $screen-md;
+$screen-md:                  992px !default;
+$screen-md-min:              $screen-md !default;
 //** Deprecated `$screen-desktop` as of v3.0.1
-$screen-desktop:             $screen-md-min;
+$screen-desktop:             $screen-md-min !default;
 
 // Large screen / wide desktop
 //** Deprecated `$screen-lg` as of v3.0.1
-$screen-lg:                  1200px;
-$screen-lg-min:              $screen-lg;
+$screen-lg:                  1200px !default;
+$screen-lg-min:              $screen-lg !default;
 //** Deprecated `$screen-lg-desktop` as of v3.0.1
-$screen-lg-desktop:          $screen-lg-min;
+$screen-lg-desktop:          $screen-lg-min !default;
 
 // So media queries don't overlap when required, provide a maximum
-$screen-xs-max:              ($screen-sm-min - 1);
-$screen-sm-max:              ($screen-md-min - 1);
-$screen-md-max:              ($screen-lg-min - 1);
+$screen-xs-max:              ($screen-sm-min - 1) !default;
+$screen-sm-max:              ($screen-md-min - 1) !default;
+$screen-md-max:              ($screen-lg-min - 1) !default;
 
 
 //== Grid system
@@ -317,14 +317,14 @@ $screen-md-max:              ($screen-lg-min - 1);
 //## Define your custom responsive grid.
 
 //** Number of columns in the grid.
-$grid-columns:              12;
+$grid-columns:              12 !default;
 //** Padding between columns. Gets divided in half for the left and right.
-$grid-gutter-width:         30px;
+$grid-gutter-width:         30px !default;
 // Navbar collapse
 //** Point at which the navbar becomes uncollapsed.
-$grid-float-breakpoint:     $screen-sm-min;
+$grid-float-breakpoint:     $screen-sm-min !default;
 //** Point at which the navbar begins collapsing.
-$grid-float-breakpoint-max: ($grid-float-breakpoint - 1);
+$grid-float-breakpoint-max: ($grid-float-breakpoint - 1) !default;
 
 
 //== Container sizes
@@ -332,19 +332,19 @@ $grid-float-breakpoint-max: ($grid-float-breakpoint - 1);
 //## Define the maximum width of `.container` for different screen sizes.
 
 // Small screen / tablet
-$container-tablet:             (720px + $grid-gutter-width);
+$container-tablet:             (720px + $grid-gutter-width) !default;
 //** For `$screen-sm-min` and up.
-$container-sm:                 $container-tablet;
+$container-sm:                 $container-tablet !default;
 
 // Medium screen / desktop
-$container-desktop:            (940px + $grid-gutter-width);
+$container-desktop:            (940px + $grid-gutter-width) !default;
 //** For `$screen-md-min` and up.
-$container-md:                 $container-desktop;
+$container-md:                 $container-desktop !default;
 
 // Large screen / wide desktop
-$container-large-desktop:      (1140px + $grid-gutter-width);
+$container-large-desktop:      (1140px + $grid-gutter-width) !default;
 //** For `$screen-lg-min` and up.
-$container-lg:                 $container-large-desktop;
+$container-lg:                 $container-large-desktop !default;
 
 
 //== Navbar
@@ -352,61 +352,61 @@ $container-lg:                 $container-large-desktop;
 //##
 
 // Basics of a navbar
-$navbar-height:                    65px;
-$navbar-margin-bottom:             $line-height-computed;
-$navbar-border-radius:             $border-radius-base;
-$navbar-padding-horizontal:        floor(($grid-gutter-width / 2));
-$navbar-padding-vertical:          (($navbar-height - $line-height-computed) / 2);
-$navbar-collapse-max-height:       340px;
+$navbar-height:                    65px !default;
+$navbar-margin-bottom:             $line-height-computed !default;
+$navbar-border-radius:             $border-radius-base !default;
+$navbar-padding-horizontal:        floor(($grid-gutter-width / 2)) !default;
+$navbar-padding-vertical:          (($navbar-height - $line-height-computed) / 2) !default;
+$navbar-collapse-max-height:       340px !default;
 
-$navbar-default-color:             $text-color;
-$navbar-default-bg:                $body-bg;
-$navbar-default-border:            #ddd;
+$navbar-default-color:             $text-color !default;
+$navbar-default-bg:                $body-bg !default;
+$navbar-default-border:            #ddd !default;
 
 // Navbar links
-$navbar-default-link-color:                $link-color;
-$navbar-default-link-hover-color:          $link-color;
-$navbar-default-link-hover-bg:             transparent;
-$navbar-default-link-active-color:         $navbar-default-link-color;
-$navbar-default-link-active-bg:            transparent;
-$navbar-default-link-disabled-color:       #333;
-$navbar-default-link-disabled-bg:          transparent;
+$navbar-default-link-color:                $link-color !default;
+$navbar-default-link-hover-color:          $link-color !default;
+$navbar-default-link-hover-bg:             transparent !default;
+$navbar-default-link-active-color:         $navbar-default-link-color !default;
+$navbar-default-link-active-bg:            transparent !default;
+$navbar-default-link-disabled-color:       #333 !default;
+$navbar-default-link-disabled-bg:          transparent !default;
 
 // Navbar brand label
-$navbar-default-brand-color:               $navbar-default-link-color;
-$navbar-default-brand-hover-color:         $navbar-default-link-hover-color;
-$navbar-default-brand-hover-bg:            transparent;
+$navbar-default-brand-color:               $navbar-default-link-color !default;
+$navbar-default-brand-hover-color:         $navbar-default-link-hover-color !default;
+$navbar-default-brand-hover-bg:            transparent !default;
 
 // Navbar toggle
-$navbar-default-toggle-hover-bg:           #ddd;
-$navbar-default-toggle-icon-bar-bg:        #ccc;
-$navbar-default-toggle-border-color:       #ddd;
+$navbar-default-toggle-hover-bg:           #ddd !default;
+$navbar-default-toggle-icon-bar-bg:        #ccc !default;
+$navbar-default-toggle-border-color:       #ddd !default;
 
 
 // Inverted navbar
 // Reset inverted navbar basics
-$navbar-inverse-color:                      $text-color;
-$navbar-inverse-bg:                         $body-bg;
-$navbar-inverse-border:                     #ddd;
+$navbar-inverse-color:                      $text-color !default;
+$navbar-inverse-bg:                         $body-bg !default;
+$navbar-inverse-border:                     #ddd !default;
 
 // Inverted navbar links
-$navbar-inverse-link-color:                 $text-color;
-$navbar-inverse-link-hover-color:           $text-color;
-$navbar-inverse-link-hover-bg:              transparent;
-$navbar-inverse-link-active-color:          $text-color;
-$navbar-inverse-link-active-bg:             transparent;
-$navbar-inverse-link-disabled-color:        #ccc;
-$navbar-inverse-link-disabled-bg:           transparent;
+$navbar-inverse-link-color:                 $text-color !default;
+$navbar-inverse-link-hover-color:           $text-color !default;
+$navbar-inverse-link-hover-bg:              transparent !default;
+$navbar-inverse-link-active-color:          $text-color !default;
+$navbar-inverse-link-active-bg:             transparent !default;
+$navbar-inverse-link-disabled-color:        #ccc !default;
+$navbar-inverse-link-disabled-bg:           transparent !default;
 
 // Inverted navbar brand label
-$navbar-inverse-brand-color:                $navbar-inverse-link-color;
-$navbar-inverse-brand-hover-color:          $navbar-inverse-link-hover-color;
-$navbar-inverse-brand-hover-bg:             transparent;
+$navbar-inverse-brand-color:                $navbar-inverse-link-color !default;
+$navbar-inverse-brand-hover-color:          $navbar-inverse-link-hover-color !default;
+$navbar-inverse-brand-hover-bg:             transparent !default;
 
 // Inverted navbar toggle
-$navbar-inverse-toggle-hover-bg:            #ddd;
-$navbar-inverse-toggle-icon-bar-bg:         #ccc;
-$navbar-inverse-toggle-border-color:        #ddd;
+$navbar-inverse-toggle-hover-bg:            #ddd !default;
+$navbar-inverse-toggle-icon-bar-bg:         #ccc !default;
+$navbar-inverse-toggle-border-color:        #ddd !default;
 
 
 //== Navs
@@ -414,97 +414,97 @@ $navbar-inverse-toggle-border-color:        #ddd;
 //##
 
 //=== Shared nav styles
-$nav-link-padding:                          10px 15px;
-$nav-link-hover-bg:                         $gray-lighter;
+$nav-link-padding:                          10px 15px !default;
+$nav-link-hover-bg:                         $gray-lighter !default;
 
-$nav-disabled-link-color:                   $gray-light;
-$nav-disabled-link-hover-color:             $gray-light;
+$nav-disabled-link-color:                   $gray-light !default;
+$nav-disabled-link-hover-color:             $gray-light !default;
 
 //== Tabs
-$nav-tabs-border-color:                     #ddd;
+$nav-tabs-border-color:                     #ddd !default;
 
-$nav-tabs-link-hover-border-color:          $gray-lighter;
+$nav-tabs-link-hover-border-color:          $gray-lighter !default;
 
-$nav-tabs-active-link-hover-bg:             $body-bg;
-$nav-tabs-active-link-hover-color:          $gray;
-$nav-tabs-active-link-hover-border-color:   #ddd;
+$nav-tabs-active-link-hover-bg:             $body-bg !default;
+$nav-tabs-active-link-hover-color:          $gray !default;
+$nav-tabs-active-link-hover-border-color:   #ddd !default;
 
-$nav-tabs-justified-link-border-color:            #ddd;
-$nav-tabs-justified-active-link-border-color:     $body-bg;
+$nav-tabs-justified-link-border-color:            #ddd !default;
+$nav-tabs-justified-active-link-border-color:     $body-bg !default;
 
 //== Pills
-$nav-pills-border-radius:                   $border-radius-base;
-$nav-pills-active-link-hover-bg:            $component-active-bg;
-$nav-pills-active-link-hover-color:         $component-active-color;
+$nav-pills-border-radius:                   $border-radius-base !default;
+$nav-pills-active-link-hover-bg:            $component-active-bg !default;
+$nav-pills-active-link-hover-color:         $component-active-color !default;
 
 
 //== Pagination
 //
 //##
 
-$pagination-color:                     $text-color;
-$pagination-bg:                        #fff;
-$pagination-border:                    #ddd;
+$pagination-color:                     $text-color !default;
+$pagination-bg:                        #fff !default;
+$pagination-border:                    #ddd !default;
 
-$pagination-hover-color:               #fff;
-$pagination-hover-bg:                  $brand-primary;
-$pagination-hover-border:              $brand-primary;
+$pagination-hover-color:               #fff !default;
+$pagination-hover-bg:                  $brand-primary !default;
+$pagination-hover-border:              $brand-primary !default;
 
-$pagination-active-color:              #fff;
-$pagination-active-bg:                 $brand-primary;
-$pagination-active-border:             $brand-primary;
+$pagination-active-color:              #fff !default;
+$pagination-active-bg:                 $brand-primary !default;
+$pagination-active-border:             $brand-primary !default;
 
-$pagination-disabled-color:            $gray-light;
-$pagination-disabled-bg:               #fff;
-$pagination-disabled-border:           #ddd;
+$pagination-disabled-color:            $gray-light !default;
+$pagination-disabled-bg:               #fff !default;
+$pagination-disabled-border:           #ddd !default;
 
 
 //== Pager
 //
 //##
 
-$pager-bg:                             $pagination-bg;
-$pager-border:                         $pagination-border;
-$pager-border-radius:                  15px;
+$pager-bg:                             $pagination-bg !default;
+$pager-border:                         $pagination-border !default;
+$pager-border-radius:                  15px !default;
 
-$pager-hover-bg:                       $pagination-hover-bg;
+$pager-hover-bg:                       $pagination-hover-bg !default;
 
-$pager-active-bg:                      $pagination-active-bg;
-$pager-active-color:                   $pagination-active-color;
+$pager-active-bg:                      $pagination-active-bg !default;
+$pager-active-color:                   $pagination-active-color !default;
 
-$pager-disabled-color:                 $gray-light;
+$pager-disabled-color:                 $gray-light !default;
 
 
 //== Jumbotron
 //
 //##
 
-$jumbotron-padding:              30px;
-$jumbotron-color:                inherit;
-$jumbotron-bg:                   darken($body-bg, 3%);
-$jumbotron-heading-color:        inherit;
-$jumbotron-font-size:            ceil(($font-size-base * 1.5));
+$jumbotron-padding:              30px !default;
+$jumbotron-color:                inherit !default;
+$jumbotron-bg:                   darken($body-bg, 3%) !default;
+$jumbotron-heading-color:        inherit !default;
+$jumbotron-font-size:            ceil(($font-size-base * 1.5)) !default;
 
 
 //== Form states and alerts
 //
 //## Define colors for form feedback states and, by default, alerts.
 
-$state-success-text:             $brand-success;
-$state-success-bg:               #dff0d8;
-$state-success-border:           $brand-success;
+$state-success-text:             $brand-success !default;
+$state-success-bg:               #dff0d8 !default;
+$state-success-border:           $brand-success !default;
 
-$state-info-text:                $brand-info;
-$state-info-bg:                  #d9edf7;
-$state-info-border:              $brand-info;
+$state-info-text:                $brand-info !default;
+$state-info-bg:                  #d9edf7 !default;
+$state-info-border:              $brand-info !default;
 
-$state-warning-text:             $brand-warning;
-$state-warning-bg:               #fcf8e3;
-$state-warning-border:           $brand-warning;
+$state-warning-text:             $brand-warning !default;
+$state-warning-bg:               #fcf8e3 !default;
+$state-warning-border:           $brand-warning !default;
 
-$state-danger-text:              $brand-danger;
-$state-danger-bg:                #f2dede;
-$state-danger-border:            $brand-danger;
+$state-danger-text:              $brand-danger !default;
+$state-danger-bg:                #f2dede !default;
+$state-danger-border:            $brand-danger !default;
 
 
 //== Tooltips
@@ -512,17 +512,17 @@ $state-danger-border:            $brand-danger;
 //##
 
 //** Tooltip max width
-$tooltip-max-width:           200px;
+$tooltip-max-width:           200px !default;
 //** Tooltip text color
-$tooltip-color:               #fff;
+$tooltip-color:               #fff !default;
 //** Tooltip background color
-$tooltip-bg:                  #000;
-$tooltip-opacity:             .9;
+$tooltip-bg:                  #000 !default;
+$tooltip-opacity:             .9 !default;
 
 //** Tooltip arrow width
-$tooltip-arrow-width:         5px;
+$tooltip-arrow-width:         5px !default;
 //** Tooltip arrow color
-$tooltip-arrow-color:         $tooltip-bg;
+$tooltip-arrow-color:         $tooltip-bg !default;
 
 
 //== Popovers
@@ -530,28 +530,28 @@ $tooltip-arrow-color:         $tooltip-bg;
 //##
 
 //** Popover body background color
-$popover-bg:                          #fff;
+$popover-bg:                          #fff !default;
 //** Popover maximum width
-$popover-max-width:                   276px;
+$popover-max-width:                   276px !default;
 //** Popover border color
-$popover-border-color:                rgba(0,0,0,.2);
+$popover-border-color:                rgba(0,0,0,.2) !default;
 //** Popover fallback border color
-$popover-fallback-border-color:       #ccc;
+$popover-fallback-border-color:       #ccc !default;
 
 //** Popover title background color
-$popover-title-bg:                    darken($popover-bg, 3%);
+$popover-title-bg:                    darken($popover-bg, 3%) !default;
 
 //** Popover arrow width
-$popover-arrow-width:                 10px;
+$popover-arrow-width:                 10px !default;
 //** Popover arrow color
-$popover-arrow-color:                 $popover-bg;
+$popover-arrow-color:                 $popover-bg !default;
 
 //** Popover outer arrow width
-$popover-arrow-outer-width:           ($popover-arrow-width + 1);
+$popover-arrow-outer-width:           ($popover-arrow-width + 1) !default;
 //** Popover outer arrow color
-$popover-arrow-outer-color:           fadein($popover-border-color, 5%);
+$popover-arrow-outer-color:           fadein($popover-border-color, 5%) !default;
 //** Popover outer arrow fallback color
-$popover-arrow-outer-fallback-color:  darken($popover-fallback-border-color, 20%);
+$popover-arrow-outer-fallback-color:  darken($popover-fallback-border-color, 20%) !default;
 
 
 //== Labels
@@ -559,22 +559,22 @@ $popover-arrow-outer-fallback-color:  darken($popover-fallback-border-color, 20%
 //##
 
 //** Default label background color
-$label-default-bg:            $btn-default-bg;
+$label-default-bg:            $btn-default-bg !default;
 //** Primary label background color
-$label-primary-bg:            $brand-primary;
+$label-primary-bg:            $brand-primary !default;
 //** Success label background color
-$label-success-bg:            $brand-success;
+$label-success-bg:            $brand-success !default;
 //** Info label background color
-$label-info-bg:               $brand-info;
+$label-info-bg:               $brand-info !default;
 //** Warning label background color
-$label-warning-bg:            $brand-warning;
+$label-warning-bg:            $brand-warning !default;
 //** Danger label background color
-$label-danger-bg:             $brand-danger;
+$label-danger-bg:             $brand-danger !default;
 
 //** Default label text color
-$label-color:                 #fff;
+$label-color:                 #fff !default;
 //** Default text color of a linked label
-$label-link-hover-color:      #fff;
+$label-link-hover-color:      #fff !default;
 
 
 //== Modals
@@ -582,57 +582,57 @@ $label-link-hover-color:      #fff;
 //##
 
 //** Padding applied to the modal body
-$modal-inner-padding:         20px;
+$modal-inner-padding:         20px !default;
 
 //** Padding applied to the modal title
-$modal-title-padding:         15px;
+$modal-title-padding:         15px !default;
 //** Modal title line-height
-$modal-title-line-height:     $line-height-base;
+$modal-title-line-height:     $line-height-base !default;
 
 //** Background color of modal content area
-$modal-content-bg:                             #fff;
+$modal-content-bg:                             #fff !default;
 //** Modal content border color
-$modal-content-border-color:                   rgba(0,0,0,.2);
+$modal-content-border-color:                   rgba(0,0,0,.2) !default;
 //** Modal content border color **for IE8**
-$modal-content-fallback-border-color:          #999;
+$modal-content-fallback-border-color:          #999 !default;
 
 //** Modal backdrop background color
-$modal-backdrop-bg:           #000;
+$modal-backdrop-bg:           #000 !default;
 //** Modal backdrop opacity
-$modal-backdrop-opacity:      .5;
+$modal-backdrop-opacity:      .5 !default;
 //** Modal header border color
-$modal-header-border-color:   #e5e5e5;
+$modal-header-border-color:   #e5e5e5 !default;
 //** Modal footer border color
-$modal-footer-border-color:   $modal-header-border-color;
+$modal-footer-border-color:   $modal-header-border-color !default;
 
-$modal-lg:                    900px;
-$modal-md:                    600px;
-$modal-sm:                    300px;
+$modal-lg:                    900px !default;
+$modal-md:                    600px !default;
+$modal-sm:                    300px !default;
 
 
 //== Alerts
 //
 //## Define alert colors, border radius, and padding.
 
-$alert-padding:               15px;
-$alert-border-radius:         $border-radius-base;
-$alert-link-font-weight:      bold;
+$alert-padding:               15px !default;
+$alert-border-radius:         $border-radius-base !default;
+$alert-link-font-weight:      bold !default;
 
-$alert-success-bg:            $state-success-border;
-$alert-success-text:          #fff;
-$alert-success-border:        $state-success-border;
+$alert-success-bg:            $state-success-border !default;
+$alert-success-text:          #fff !default;
+$alert-success-border:        $state-success-border !default;
 
-$alert-info-bg:               $state-info-border;
-$alert-info-text:             #fff;
-$alert-info-border:           $state-info-border;
+$alert-info-bg:               $state-info-border !default;
+$alert-info-text:             #fff !default;
+$alert-info-border:           $state-info-border !default;
 
-$alert-warning-bg:            $state-warning-border;
-$alert-warning-text:          #fff;
-$alert-warning-border:        $state-warning-border;
+$alert-warning-bg:            $state-warning-border !default;
+$alert-warning-text:          #fff !default;
+$alert-warning-border:        $state-warning-border !default;
 
-$alert-danger-bg:             $state-danger-border;
-$alert-danger-text:           #fff;
-$alert-danger-border:         $state-danger-border;
+$alert-danger-bg:             $state-danger-border !default;
+$alert-danger-text:           #fff !default;
+$alert-danger-border:         $state-danger-border !default;
 
 
 //== Progress bars
@@ -640,22 +640,22 @@ $alert-danger-border:         $state-danger-border;
 //##
 
 //** Background color of the whole progress component
-$progress-bg:                 #f5f5f5;
+$progress-bg:                 #f5f5f5 !default;
 //** Progress bar text color
-$progress-bar-color:          #fff;
+$progress-bar-color:          #fff !default;
 //** Variable for setting rounded corners on progress bar.
-$progress-border-radius:      $border-radius-base;
+$progress-border-radius:      $border-radius-base !default;
 
 //** Default progress bar color
-$progress-bar-bg:             $brand-primary;
+$progress-bar-bg:             $brand-primary !default;
 //** Success progress bar color
-$progress-bar-success-bg:     $brand-success;
+$progress-bar-success-bg:     $brand-success !default;
 //** Warning progress bar color
-$progress-bar-warning-bg:     $brand-warning;
+$progress-bar-warning-bg:     $brand-warning !default;
 //** Danger progress bar color
-$progress-bar-danger-bg:      $brand-danger;
+$progress-bar-danger-bg:      $brand-danger !default;
 //** Info progress bar color
-$progress-bar-info-bg:        $brand-info;
+$progress-bar-info-bg:        $brand-info !default;
 
 
 //== List group
@@ -663,72 +663,72 @@ $progress-bar-info-bg:        $brand-info;
 //##
 
 //** Background color on `.list-group-item`
-$list-group-bg:                 #fff;
+$list-group-bg:                 #fff !default;
 //** `.list-group-item` border color
-$list-group-border:             #ddd;
+$list-group-border:             #ddd !default;
 //** List group border radius
-$list-group-border-radius:      $border-radius-base;
+$list-group-border-radius:      $border-radius-base !default;
 
 //** Background color of single list items on hover
-$list-group-hover-bg:           #f5f5f5;
+$list-group-hover-bg:           #f5f5f5 !default;
 //** Text color of active list items
-$list-group-active-color:       $component-active-color;
+$list-group-active-color:       $component-active-color !default;
 //** Background color of active list items
-$list-group-active-bg:          $component-active-bg;
+$list-group-active-bg:          $component-active-bg !default;
 //** Border color of active list elements
-$list-group-active-border:      $list-group-active-bg;
+$list-group-active-border:      $list-group-active-bg !default;
 //** Text color for content within active list items
-$list-group-active-text-color:  lighten($list-group-active-bg, 40%);
+$list-group-active-text-color:  lighten($list-group-active-bg, 40%) !default;
 
 //** Text color of disabled list items
-$list-group-disabled-color:      $gray-light;
+$list-group-disabled-color:      $gray-light !default;
 //** Background color of disabled list items
-$list-group-disabled-bg:         $gray-lighter;
+$list-group-disabled-bg:         $gray-lighter !default;
 //** Text color for content within disabled list items
-$list-group-disabled-text-color: $list-group-disabled-color;
+$list-group-disabled-text-color: $list-group-disabled-color !default;
 
-$list-group-link-color:         #555;
-$list-group-link-hover-color:   $list-group-link-color;
-$list-group-link-heading-color: #333;
+$list-group-link-color:         #555 !default;
+$list-group-link-hover-color:   $list-group-link-color !default;
+$list-group-link-heading-color: #333 !default;
 
 
 //== Panels
 //
 //##
 
-$panel-bg:                    #fff;
-$panel-body-padding:          15px;
-$panel-heading-padding:       10px 15px;
-$panel-footer-padding:        $panel-heading-padding;
-$panel-border-radius:         $border-radius-base;
+$panel-bg:                    #fff !default;
+$panel-body-padding:          15px !default;
+$panel-heading-padding:       10px 15px !default;
+$panel-footer-padding:        $panel-heading-padding !default;
+$panel-border-radius:         $border-radius-base !default;
 
 //** Border color for elements within panels
-$panel-inner-border:          #ddd;
-$panel-footer-bg:             #fff;
+$panel-inner-border:          #ddd !default;
+$panel-footer-bg:             #fff !default;
 
-$panel-default-text:          $gray-dark;
-$panel-default-border:        #ddd;
-$panel-default-heading-bg:    #f5f5f5;
+$panel-default-text:          $gray-dark !default;
+$panel-default-border:        #ddd !default;
+$panel-default-heading-bg:    #f5f5f5 !default;
 
-$panel-primary-text:          #fff;
-$panel-primary-border:        $brand-primary;
-$panel-primary-heading-bg:    $brand-primary;
+$panel-primary-text:          #fff !default;
+$panel-primary-border:        $brand-primary !default;
+$panel-primary-heading-bg:    $brand-primary !default;
 
-$panel-success-text:          #fff;
-$panel-success-border:        $state-success-border;
-$panel-success-heading-bg:    $state-success-border;
+$panel-success-text:          #fff !default;
+$panel-success-border:        $state-success-border !default;
+$panel-success-heading-bg:    $state-success-border !default;
 
-$panel-info-text:             #fff;
-$panel-info-border:           $state-info-border;
-$panel-info-heading-bg:       $state-info-border;
+$panel-info-text:             #fff !default;
+$panel-info-border:           $state-info-border !default;
+$panel-info-heading-bg:       $state-info-border !default;
 
-$panel-warning-text:          #fff;
-$panel-warning-border:        $state-warning-border;
-$panel-warning-heading-bg:    $state-warning-border;
+$panel-warning-text:          #fff !default;
+$panel-warning-border:        $state-warning-border !default;
+$panel-warning-heading-bg:    $state-warning-border !default;
 
-$panel-danger-text:           #fff;
-$panel-danger-border:         $state-danger-border;
-$panel-danger-heading-bg:     $state-danger-border;
+$panel-danger-text:           #fff !default;
+$panel-danger-border:         $state-danger-border !default;
+$panel-danger-heading-bg:     $state-danger-border !default;
 
 
 //== Thumbnails
@@ -736,103 +736,103 @@ $panel-danger-heading-bg:     $state-danger-border;
 //##
 
 //** Padding around the thumbnail image
-$thumbnail-padding:           4px;
+$thumbnail-padding:           4px !default;
 //** Thumbnail background color
-$thumbnail-bg:                $body-bg;
+$thumbnail-bg:                $body-bg !default;
 //** Thumbnail border color
-$thumbnail-border:            #ddd;
+$thumbnail-border:            #ddd !default;
 //** Thumbnail border radius
-$thumbnail-border-radius:     $border-radius-base;
+$thumbnail-border-radius:     $border-radius-base !default;
 
 //** Custom text color for thumbnail captions
-$thumbnail-caption-color:     $text-color;
+$thumbnail-caption-color:     $text-color !default;
 //** Padding around the thumbnail caption
-$thumbnail-caption-padding:   9px;
+$thumbnail-caption-padding:   9px !default;
 
 
 //== Wells
 //
 //##
 
-$well-bg:                     darken($body-bg, 3%);
-$well-border:                 darken($well-bg, 7%);
+$well-bg:                     darken($body-bg, 3%) !default;
+$well-border:                 darken($well-bg, 7%) !default;
 
 
 //== Badges
 //
 //##
 
-$badge-color:                 #fff;
+$badge-color:                 #fff !default;
 //** Linked badge text color on hover
-$badge-link-hover-color:      #fff;
-$badge-bg:                    $brand-primary;
+$badge-link-hover-color:      #fff !default;
+$badge-bg:                    $brand-primary !default;
 
 //** Badge text color in active nav link
-$badge-active-color:          $link-color;
+$badge-active-color:          $link-color !default;
 //** Badge background color in active nav link
-$badge-active-bg:             #fff;
+$badge-active-bg:             #fff !default;
 
-$badge-font-weight:           bold;
-$badge-line-height:           1;
-$badge-border-radius:         10px;
+$badge-font-weight:           bold !default;
+$badge-line-height:           1 !default;
+$badge-border-radius:         10px !default;
 
 
 //== Breadcrumbs
 //
 //##
 
-$breadcrumb-padding-vertical:   8px;
-$breadcrumb-padding-horizontal: 15px;
+$breadcrumb-padding-vertical:   8px !default;
+$breadcrumb-padding-horizontal: 15px !default;
 //** Breadcrumb background color
-$breadcrumb-bg:                 #f5f5f5;
+$breadcrumb-bg:                 #f5f5f5 !default;
 //** Breadcrumb text color
-$breadcrumb-color:              #ccc;
+$breadcrumb-color:              #ccc !default;
 //** Text color of current page in the breadcrumb
-$breadcrumb-active-color:       $gray-light;
+$breadcrumb-active-color:       $gray-light !default;
 //** Textual separator for between breadcrumb elements
-$breadcrumb-separator:          "/";
+$breadcrumb-separator:          "/" !default;
 
 
 //== Carousel
 //
 //##
 
-$carousel-text-shadow:                        0 1px 2px rgba(0,0,0,.6);
+$carousel-text-shadow:                        0 1px 2px rgba(0,0,0,.6) !default;
 
-$carousel-control-color:                      #fff;
-$carousel-control-width:                      15%;
-$carousel-control-opacity:                    .5;
-$carousel-control-font-size:                  20px;
+$carousel-control-color:                      #fff !default;
+$carousel-control-width:                      15% !default;
+$carousel-control-opacity:                    .5 !default;
+$carousel-control-font-size:                  20px !default;
 
-$carousel-indicator-active-bg:                #fff;
-$carousel-indicator-border-color:             #fff;
+$carousel-indicator-active-bg:                #fff !default;
+$carousel-indicator-border-color:             #fff !default;
 
-$carousel-caption-color:                      #fff;
+$carousel-caption-color:                      #fff !default;
 
 
 //== Close
 //
 //##
 
-$close-font-weight:           bold;
-$close-color:                 #fff;
-$close-text-shadow:           0 1px 0 #fff;
+$close-font-weight:           bold !default;
+$close-color:                 #fff !default;
+$close-text-shadow:           0 1px 0 #fff !default;
 
 
 //== Code
 //
 //##
 
-$code-color:                  #c7254e;
-$code-bg:                     #f9f2f4;
+$code-color:                  #c7254e !default;
+$code-bg:                     #f9f2f4 !default;
 
-$kbd-color:                   #fff;
-$kbd-bg:                      #333;
+$kbd-color:                   #fff !default;
+$kbd-bg:                      #333 !default;
 
-$pre-bg:                      #f5f5f5;
-$pre-color:                   $gray-dark;
-$pre-border-color:            #ccc;
-$pre-scrollable-max-height:   340px;
+$pre-bg:                      #f5f5f5 !default;
+$pre-color:                   $gray-dark !default;
+$pre-border-color:            #ccc !default;
+$pre-scrollable-max-height:   340px !default;
 
 
 //== Type
@@ -840,22 +840,22 @@ $pre-scrollable-max-height:   340px;
 //##
 
 //** Horizontal offset for forms and lists.
-$component-offset-horizontal: 180px;
+$component-offset-horizontal: 180px !default;
 //** Text muted color
-$text-muted:                  $gray-light;
+$text-muted:                  $gray-light !default;
 //** Abbreviations and acronyms border color
-$abbr-border-color:           $gray-light;
+$abbr-border-color:           $gray-light !default;
 //** Headings small color
-$headings-small-color:        $gray-light;
+$headings-small-color:        $gray-light !default;
 //** Blockquote small color
-$blockquote-small-color:      $text-color;
+$blockquote-small-color:      $text-color !default;
 //** Blockquote font size
-$blockquote-font-size:        ($font-size-base * 1.25);
+$blockquote-font-size:        ($font-size-base * 1.25) !default;
 //** Blockquote border color
-$blockquote-border-color:     $brand-primary;
+$blockquote-border-color:     $brand-primary !default;
 //** Page header border color
-$page-header-border-color:    #ddd;
+$page-header-border-color:    #ddd !default;
 //** Width of horizontal description list titles
-$dl-horizontal-offset:        $component-offset-horizontal;
+$dl-horizontal-offset:        $component-offset-horizontal !default;
 //** Horizontal line color.
-$hr-border:                   $gray-lighter;
+$hr-border:                   $gray-lighter !default;
diff --git a/sandstone/_variables.scss b/sandstone/_variables.scss
index b5ed56e3..e4012a01 100644
--- a/sandstone/_variables.scss
+++ b/sandstone/_variables.scss
@@ -7,18 +7,18 @@
 //
 //## Gray and brand colors for use across Bootstrap.
 
-$gray-base:              #000;
-$gray-darker:            #3E3F3A;
-$gray-dark:              #8E8C84;
-$gray:                   #98978B;
-$gray-light:             #DFD7CA;
-$gray-lighter:           #F8F5F0;
+$gray-base:              #000 !default;
+$gray-darker:            #3E3F3A !default;
+$gray-dark:              #8E8C84 !default;
+$gray:                   #98978B !default;
+$gray-light:             #DFD7CA !default;
+$gray-lighter:           #F8F5F0 !default;
 
-$brand-primary:         #325D88;
-$brand-success:         #93C54B;
-$brand-info:            #29ABE0;
-$brand-warning:         #F47C3C;
-$brand-danger:          #d9534f;
+$brand-primary:         #325D88 !default;
+$brand-success:         #93C54B !default;
+$brand-info:            #29ABE0 !default;
+$brand-warning:         #F47C3C !default;
+$brand-danger:          #d9534f !default;
 
 
 //== Scaffolding
@@ -26,49 +26,49 @@ $brand-danger:          #d9534f;
 //## Settings for some of the most global styles.
 
 //** Background color for ``.
-$body-bg:               #fff;
+$body-bg:               #fff !default;
 //** Global text color on ``.
-$text-color:            #3E3F3A;
+$text-color:            #3E3F3A !default;
 
 //** Global textual link color.
-$link-color:            $brand-success;
+$link-color:            $brand-success !default;
 //** Link hover color set via `darken()` function.
-$link-hover-color:      darken($link-color, 10%);
+$link-hover-color:      darken($link-color, 10%) !default;
 //** Link hover decoration.
-$link-hover-decoration: underline;
+$link-hover-decoration: underline !default;
 
 
 //== Typography
 //
 //## Font, line-height, and color for body text, headings, and more.
 
-$font-family-sans-serif:  "Roboto", "Helvetica Neue", Helvetica, Arial, sans-serif;
-$font-family-serif:       Georgia, "Times New Roman", Times, serif;
+$font-family-sans-serif:  "Roboto", "Helvetica Neue", Helvetica, Arial, sans-serif !default;
+$font-family-serif:       Georgia, "Times New Roman", Times, serif !default;
 //** Default monospace fonts for ``, ``, and `
`.
-$font-family-monospace:   Menlo, Monaco, Consolas, "Courier New", monospace;
-$font-family-base:        $font-family-sans-serif;
+$font-family-monospace:   Menlo, Monaco, Consolas, "Courier New", monospace !default;
+$font-family-base:        $font-family-sans-serif !default;
 
-$font-size-base:          14px;
-$font-size-large:         ceil(($font-size-base * 1.25)); // ~18px
-$font-size-small:         ceil(($font-size-base * 0.85)); // ~12px
+$font-size-base:          14px !default;
+$font-size-large:         ceil(($font-size-base * 1.25)) !default; // ~18px
+$font-size-small:         ceil(($font-size-base * 0.85)) !default; // ~12px
 
-$font-size-h1:            floor(($font-size-base * 2.6)); // ~36px
-$font-size-h2:            floor(($font-size-base * 2.15)); // ~30px
-$font-size-h3:            ceil(($font-size-base * 1.7)); // ~24px
-$font-size-h4:            ceil(($font-size-base * 1.25)); // ~18px
-$font-size-h5:            $font-size-base;
-$font-size-h6:            ceil(($font-size-base * 0.85)); // ~12px
+$font-size-h1:            floor(($font-size-base * 2.6)) !default; // ~36px
+$font-size-h2:            floor(($font-size-base * 2.15)) !default; // ~30px
+$font-size-h3:            ceil(($font-size-base * 1.7)) !default; // ~24px
+$font-size-h4:            ceil(($font-size-base * 1.25)) !default; // ~18px
+$font-size-h5:            $font-size-base !default;
+$font-size-h6:            ceil(($font-size-base * 0.85)) !default; // ~12px
 
 //** Unit-less `line-height` for use in components like buttons.
-$line-height-base:        1.428571429; // 20/14
+$line-height-base:        1.428571429 !default; // 20/14
 //** Computed "line-height" (`font-size` * `line-height`) for use with `margin`, `padding`, etc.
-$line-height-computed:    floor(($font-size-base * $line-height-base)); // ~20px
+$line-height-computed:    floor(($font-size-base * $line-height-base)) !default; // ~20px
 
 //** By default, this inherits from the ``.
-$headings-font-family:    inherit;
-$headings-font-weight:    400;
-$headings-line-height:    1.1;
-$headings-color:          inherit;
+$headings-font-family:    inherit !default;
+$headings-font-weight:    400 !default;
+$headings-line-height:    1.1 !default;
+$headings-color:          inherit !default;
 
 
 //== Iconography
@@ -76,45 +76,45 @@ $headings-color:          inherit;
 //## Specify custom location and filename of the included Glyphicons icon font. Useful for those including Bootstrap via Bower.
 
 //** Load fonts from this directory.
-$icon-font-path:          "../fonts/";
+$icon-font-path:          "../fonts/" !default;
 //** File name for all font files.
-$icon-font-name:          "glyphicons-halflings-regular";
+$icon-font-name:          "glyphicons-halflings-regular" !default;
 //** Element ID within SVG icon file.
-$icon-font-svg-id:        "glyphicons_halflingsregular";
+$icon-font-svg-id:        "glyphicons_halflingsregular" !default;
 
 
 //== Components
 //
 //## Define common padding and border radius sizes and more. Values based on 14px text and 1.428 line-height (~20px to start).
 
-$padding-base-vertical:     12px;
-$padding-base-horizontal:   16px;
+$padding-base-vertical:     12px !default;
+$padding-base-horizontal:   16px !default;
 
-$padding-large-vertical:    20px;
-$padding-large-horizontal:  30px;
+$padding-large-vertical:    20px !default;
+$padding-large-horizontal:  30px !default;
 
-$padding-small-vertical:    5px;
-$padding-small-horizontal:  10px;
+$padding-small-vertical:    5px !default;
+$padding-small-horizontal:  10px !default;
 
-$padding-xs-vertical:       1px;
-$padding-xs-horizontal:     5px;
+$padding-xs-vertical:       1px !default;
+$padding-xs-horizontal:     5px !default;
 
-$line-height-large:         1.3333333; // extra decimals for Win 8.1 Chrome
-$line-height-small:         1.5;
+$line-height-large:         1.3333333 !default; // extra decimals for Win 8.1 Chrome
+$line-height-small:         1.5 !default;
 
-$border-radius-base:        4px;
-$border-radius-large:       6px;
-$border-radius-small:       3px;
+$border-radius-base:        4px !default;
+$border-radius-large:       6px !default;
+$border-radius-small:       3px !default;
 
 //** Global color for active items (e.g., navs or dropdowns).
-$component-active-color:    $gray;
+$component-active-color:    $gray !default;
 //** Global background color for active items (e.g., navs or dropdowns).
-$component-active-bg:       $gray-lighter;
+$component-active-bg:       $gray-lighter !default;
 
 //** Width of the `border` for generating carets that indicator dropdowns.
-$caret-width-base:          4px;
+$caret-width-base:          4px !default;
 //** Carets increase slightly in size for larger components.
-$caret-width-large:         5px;
+$caret-width-large:         5px !default;
 
 
 //== Tables
@@ -122,53 +122,53 @@ $caret-width-large:         5px;
 //## Customizes the `.table` component with basic values, each used across all table variations.
 
 //** Padding for ``s and ``s.
-$table-cell-padding:            8px;
+$table-cell-padding:            8px !default;
 //** Padding for cells in `.table-condensed`.
-$table-condensed-cell-padding:  5px;
+$table-condensed-cell-padding:  5px !default;
 
 //** Default background color used for all tables.
-$table-bg:                      transparent;
+$table-bg:                      transparent !default;
 //** Background color used for `.table-striped`.
-$table-bg-accent:               $gray-lighter;
+$table-bg-accent:               $gray-lighter !default;
 //** Background color used for `.table-hover`.
-$table-bg-hover:                $gray-lighter;
-$table-bg-active:               $table-bg-hover;
+$table-bg-hover:                $gray-lighter !default;
+$table-bg-active:               $table-bg-hover !default;
 
 //** Border color for table and cell borders.
-$table-border-color:            $gray-light;
+$table-border-color:            $gray-light !default;
 
 
 //== Buttons
 //
 //## For each of Bootstrap's buttons, define text, background and border color.
 
-$btn-font-weight:                normal;
+$btn-font-weight:                normal !default;
 
-$btn-default-color:              #fff;
-$btn-default-bg:                 $gray-darker;
-$btn-default-border:             transparent;
+$btn-default-color:              #fff !default;
+$btn-default-bg:                 $gray-darker !default;
+$btn-default-border:             transparent !default;
 
-$btn-primary-color:              #fff;
-$btn-primary-bg:                 $brand-primary;
-$btn-primary-border:             transparent;
+$btn-primary-color:              #fff !default;
+$btn-primary-bg:                 $brand-primary !default;
+$btn-primary-border:             transparent !default;
 
-$btn-success-color:              #fff;
-$btn-success-bg:                 $brand-success;
-$btn-success-border:             transparent;
+$btn-success-color:              #fff !default;
+$btn-success-bg:                 $brand-success !default;
+$btn-success-border:             transparent !default;
 
-$btn-info-color:                 #fff;
-$btn-info-bg:                    $brand-info;
-$btn-info-border:                transparent;
+$btn-info-color:                 #fff !default;
+$btn-info-bg:                    $brand-info !default;
+$btn-info-border:                transparent !default;
 
-$btn-warning-color:              #fff;
-$btn-warning-bg:                 $brand-warning;
-$btn-warning-border:             transparent;
+$btn-warning-color:              #fff !default;
+$btn-warning-bg:                 $brand-warning !default;
+$btn-warning-border:             transparent !default;
 
-$btn-danger-color:               #fff;
-$btn-danger-bg:                  $brand-danger;
-$btn-danger-border:              transparent;
+$btn-danger-color:               #fff !default;
+$btn-danger-bg:                  $brand-danger !default;
+$btn-danger-border:              transparent !default;
 
-$btn-link-disabled-color:        $gray-light;
+$btn-link-disabled-color:        $gray-light !default;
 
 
 //== Forms
@@ -176,50 +176,50 @@ $btn-link-disabled-color:        $gray-light;
 //##
 
 //** `` background color
-$input-bg:                       #fff;
+$input-bg:                       #fff !default;
 //** `` background color
-$input-bg-disabled:              $gray-lighter;
+$input-bg-disabled:              $gray-lighter !default;
 
 //** Text color for ``s
-$input-color:                    $text-color;
+$input-color:                    $text-color !default;
 //** `` border color
-$input-border:                   $gray-light;
+$input-border:                   $gray-light !default;
 
 // TODO: Rename `$input-border-radius` to `$input-border-radius-base` in v4
 //** Default `.form-control` border radius
 // This has no effect on ``s in CSS.
-$input-border-radius:            $border-radius-base;
+$input-border-radius:            $border-radius-base !default;
 //** Large `.form-control` border radius
-$input-border-radius-large:      $border-radius-large;
+$input-border-radius-large:      $border-radius-large !default;
 //** Small `.form-control` border radius
-$input-border-radius-small:      $border-radius-small;
+$input-border-radius-small:      $border-radius-small !default;
 
 //** Border color for inputs on focus
-$input-border-focus:             transparent;
+$input-border-focus:             transparent !default;
 
 //** Placeholder text color
-$input-color-placeholder:        $gray-light;
+$input-color-placeholder:        $gray-light !default;
 
 //** Default `.form-control` height
-$input-height-base:              ($line-height-computed + ($padding-base-vertical * 2) + 2);
+$input-height-base:              ($line-height-computed + ($padding-base-vertical * 2) + 2) !default;
 //** Large `.form-control` height
-$input-height-large:             (ceil($font-size-large * $line-height-large) + ($padding-large-vertical * 2) + 2);
+$input-height-large:             (ceil($font-size-large * $line-height-large) + ($padding-large-vertical * 2) + 2) !default;
 //** Small `.form-control` height
-$input-height-small:             (floor($font-size-small * $line-height-small) + ($padding-small-vertical * 2) + 2);
+$input-height-small:             (floor($font-size-small * $line-height-small) + ($padding-small-vertical * 2) + 2) !default;
 
 //** `.form-group` margin
-$form-group-margin-bottom:       15px;
+$form-group-margin-bottom:       15px !default;
 
-$legend-color:                   $headings-color;
-$legend-border-color:            transparent;
+$legend-color:                   $headings-color !default;
+$legend-border-color:            transparent !default;
 
 //** Background color for textual input addons
-$input-group-addon-bg:           $gray-lighter;
+$input-group-addon-bg:           $gray-lighter !default;
 //** Border color for textual input addons
-$input-group-addon-border-color: $input-border;
+$input-group-addon-border-color: $input-border !default;
 
 //** Disabled cursor for form controls and buttons.
-$cursor-disabled:                not-allowed;
+$cursor-disabled:                not-allowed !default;
 
 
 //== Dropdowns
@@ -227,34 +227,34 @@ $cursor-disabled:                not-allowed;
 //## Dropdown menu container and contents.
 
 //** Background for the dropdown menu.
-$dropdown-bg:                    #fff;
+$dropdown-bg:                    #fff !default;
 //** Dropdown menu `border-color`.
-$dropdown-border:                $gray-light;
+$dropdown-border:                $gray-light !default;
 //** Dropdown menu `border-color` **for IE8**.
-$dropdown-fallback-border:       $gray-light;
+$dropdown-fallback-border:       $gray-light !default;
 //** Divider color for between dropdown items.
-$dropdown-divider-bg:            $gray-lighter;
+$dropdown-divider-bg:            $gray-lighter !default;
 
 //** Dropdown link text color.
-$dropdown-link-color:            $gray;
+$dropdown-link-color:            $gray !default;
 //** Hover color for dropdown links.
-$dropdown-link-hover-color:      $dropdown-link-color;
+$dropdown-link-hover-color:      $dropdown-link-color !default;
 //** Hover background for dropdown links.
-$dropdown-link-hover-bg:         $gray-lighter;
+$dropdown-link-hover-bg:         $gray-lighter !default;
 
 //** Active dropdown menu item text color.
-$dropdown-link-active-color:     $component-active-color;
+$dropdown-link-active-color:     $component-active-color !default;
 //** Active dropdown menu item background color.
-$dropdown-link-active-bg:        $component-active-bg;
+$dropdown-link-active-bg:        $component-active-bg !default;
 
 //** Disabled dropdown menu item background color.
-$dropdown-link-disabled-color:   $gray-light;
+$dropdown-link-disabled-color:   $gray-light !default;
 
 //** Text color for headers within dropdown menus.
-$dropdown-header-color:          $gray-light;
+$dropdown-header-color:          $gray-light !default;
 
 //** Deprecated `$dropdown-caret-color` as of v3.1.0
-$dropdown-caret-color:           #000;
+$dropdown-caret-color:           #000 !default;
 
 
 //-- Z-index master list
@@ -264,13 +264,13 @@ $dropdown-caret-color:           #000;
 //
 // Note: These variables are not generated into the Customizer.
 
-$zindex-navbar:            1000;
-$zindex-dropdown:          1000;
-$zindex-popover:           1060;
-$zindex-tooltip:           1070;
-$zindex-navbar-fixed:      1030;
-$zindex-modal-background:  1040;
-$zindex-modal:             1050;
+$zindex-navbar:            1000 !default;
+$zindex-dropdown:          1000 !default;
+$zindex-popover:           1060 !default;
+$zindex-tooltip:           1070 !default;
+$zindex-navbar-fixed:      1030 !default;
+$zindex-modal-background:  1040 !default;
+$zindex-modal:             1050 !default;
 
 
 //== Media queries breakpoints
@@ -279,37 +279,37 @@ $zindex-modal:             1050;
 
 // Extra small screen / phone
 //** Deprecated `$screen-xs` as of v3.0.1
-$screen-xs:                  480px;
+$screen-xs:                  480px !default;
 //** Deprecated `$screen-xs-min` as of v3.2.0
-$screen-xs-min:              $screen-xs;
+$screen-xs-min:              $screen-xs !default;
 //** Deprecated `$screen-phone` as of v3.0.1
-$screen-phone:               $screen-xs-min;
+$screen-phone:               $screen-xs-min !default;
 
 // Small screen / tablet
 //** Deprecated `$screen-sm` as of v3.0.1
-$screen-sm:                  768px;
-$screen-sm-min:              $screen-sm;
+$screen-sm:                  768px !default;
+$screen-sm-min:              $screen-sm !default;
 //** Deprecated `$screen-tablet` as of v3.0.1
-$screen-tablet:              $screen-sm-min;
+$screen-tablet:              $screen-sm-min !default;
 
 // Medium screen / desktop
 //** Deprecated `$screen-md` as of v3.0.1
-$screen-md:                  992px;
-$screen-md-min:              $screen-md;
+$screen-md:                  992px !default;
+$screen-md-min:              $screen-md !default;
 //** Deprecated `$screen-desktop` as of v3.0.1
-$screen-desktop:             $screen-md-min;
+$screen-desktop:             $screen-md-min !default;
 
 // Large screen / wide desktop
 //** Deprecated `$screen-lg` as of v3.0.1
-$screen-lg:                  1200px;
-$screen-lg-min:              $screen-lg;
+$screen-lg:                  1200px !default;
+$screen-lg-min:              $screen-lg !default;
 //** Deprecated `$screen-lg-desktop` as of v3.0.1
-$screen-lg-desktop:          $screen-lg-min;
+$screen-lg-desktop:          $screen-lg-min !default;
 
 // So media queries don't overlap when required, provide a maximum
-$screen-xs-max:              ($screen-sm-min - 1);
-$screen-sm-max:              ($screen-md-min - 1);
-$screen-md-max:              ($screen-lg-min - 1);
+$screen-xs-max:              ($screen-sm-min - 1) !default;
+$screen-sm-max:              ($screen-md-min - 1) !default;
+$screen-md-max:              ($screen-lg-min - 1) !default;
 
 
 //== Grid system
@@ -317,14 +317,14 @@ $screen-md-max:              ($screen-lg-min - 1);
 //## Define your custom responsive grid.
 
 //** Number of columns in the grid.
-$grid-columns:              12;
+$grid-columns:              12 !default;
 //** Padding between columns. Gets divided in half for the left and right.
-$grid-gutter-width:         30px;
+$grid-gutter-width:         30px !default;
 // Navbar collapse
 //** Point at which the navbar becomes uncollapsed.
-$grid-float-breakpoint:     $screen-sm-min;
+$grid-float-breakpoint:     $screen-sm-min !default;
 //** Point at which the navbar begins collapsing.
-$grid-float-breakpoint-max: ($grid-float-breakpoint - 1);
+$grid-float-breakpoint-max: ($grid-float-breakpoint - 1) !default;
 
 
 //== Container sizes
@@ -332,19 +332,19 @@ $grid-float-breakpoint-max: ($grid-float-breakpoint - 1);
 //## Define the maximum width of `.container` for different screen sizes.
 
 // Small screen / tablet
-$container-tablet:             (720px + $grid-gutter-width);
+$container-tablet:             (720px + $grid-gutter-width) !default;
 //** For `$screen-sm-min` and up.
-$container-sm:                 $container-tablet;
+$container-sm:                 $container-tablet !default;
 
 // Medium screen / desktop
-$container-desktop:            (940px + $grid-gutter-width);
+$container-desktop:            (940px + $grid-gutter-width) !default;
 //** For `$screen-md-min` and up.
-$container-md:                 $container-desktop;
+$container-md:                 $container-desktop !default;
 
 // Large screen / wide desktop
-$container-large-desktop:      (1140px + $grid-gutter-width);
+$container-large-desktop:      (1140px + $grid-gutter-width) !default;
 //** For `$screen-lg-min` and up.
-$container-lg:                 $container-large-desktop;
+$container-lg:                 $container-large-desktop !default;
 
 
 //== Navbar
@@ -352,61 +352,61 @@ $container-lg:                 $container-large-desktop;
 //##
 
 // Basics of a navbar
-$navbar-height:                    60px;
-$navbar-margin-bottom:             $line-height-computed;
-$navbar-border-radius:             $border-radius-base;
-$navbar-padding-horizontal:        floor(($grid-gutter-width / 2));
-$navbar-padding-vertical:          (($navbar-height - $line-height-computed) / 2);
-$navbar-collapse-max-height:       340px;
+$navbar-height:                    60px !default;
+$navbar-margin-bottom:             $line-height-computed !default;
+$navbar-border-radius:             $border-radius-base !default;
+$navbar-padding-horizontal:        floor(($grid-gutter-width / 2)) !default;
+$navbar-padding-vertical:          (($navbar-height - $line-height-computed) / 2) !default;
+$navbar-collapse-max-height:       340px !default;
 
-$navbar-default-color:             $gray-dark;
-$navbar-default-bg:                $gray-darker;
-$navbar-default-border:            $gray-darker;
+$navbar-default-color:             $gray-dark !default;
+$navbar-default-bg:                $gray-darker !default;
+$navbar-default-border:            $gray-darker !default;
 
 // Navbar links
-$navbar-default-link-color:                $gray;
-$navbar-default-link-hover-color:          #fff;
-$navbar-default-link-hover-bg:             transparent;
-$navbar-default-link-active-color:         #fff;
-$navbar-default-link-active-bg:            darken($navbar-default-bg, 2%);
-$navbar-default-link-disabled-color:       #ccc;
-$navbar-default-link-disabled-bg:          transparent;
+$navbar-default-link-color:                $gray !default;
+$navbar-default-link-hover-color:          #fff !default;
+$navbar-default-link-hover-bg:             transparent !default;
+$navbar-default-link-active-color:         #fff !default;
+$navbar-default-link-active-bg:            darken($navbar-default-bg, 2%) !default;
+$navbar-default-link-disabled-color:       #ccc !default;
+$navbar-default-link-disabled-bg:          transparent !default;
 
 // Navbar brand label
-$navbar-default-brand-color:               #fff;
-$navbar-default-brand-hover-color:         #fff;
-$navbar-default-brand-hover-bg:            transparent;
+$navbar-default-brand-color:               #fff !default;
+$navbar-default-brand-hover-color:         #fff !default;
+$navbar-default-brand-hover-bg:            transparent !default;
 
 // Navbar toggle
-$navbar-default-toggle-hover-bg:           $navbar-default-link-active-bg;
-$navbar-default-toggle-icon-bar-bg:        $navbar-default-link-color;
-$navbar-default-toggle-border-color:       transparent;
+$navbar-default-toggle-hover-bg:           $navbar-default-link-active-bg !default;
+$navbar-default-toggle-icon-bar-bg:        $navbar-default-link-color !default;
+$navbar-default-toggle-border-color:       transparent !default;
 
 
 // Inverted navbar
 // Reset inverted navbar basics
-$navbar-inverse-color:                      $gray-light;
-$navbar-inverse-bg:                         $brand-success;
-$navbar-inverse-border:                     $brand-success;
+$navbar-inverse-color:                      $gray-light !default;
+$navbar-inverse-bg:                         $brand-success !default;
+$navbar-inverse-border:                     $brand-success !default;
 
 // Inverted navbar links
-$navbar-inverse-link-color:                 darken($brand-success, 15%);
-$navbar-inverse-link-hover-color:           #fff;
-$navbar-inverse-link-hover-bg:              transparent;
-$navbar-inverse-link-active-color:          $navbar-inverse-link-hover-color;
-$navbar-inverse-link-active-bg:             darken($navbar-inverse-bg, 4%);
-$navbar-inverse-link-disabled-color:        #444;
-$navbar-inverse-link-disabled-bg:           transparent;
+$navbar-inverse-link-color:                 darken($brand-success, 15%) !default;
+$navbar-inverse-link-hover-color:           #fff !default;
+$navbar-inverse-link-hover-bg:              transparent !default;
+$navbar-inverse-link-active-color:          $navbar-inverse-link-hover-color !default;
+$navbar-inverse-link-active-bg:             darken($navbar-inverse-bg, 4%) !default;
+$navbar-inverse-link-disabled-color:        #444 !default;
+$navbar-inverse-link-disabled-bg:           transparent !default;
 
 // Inverted navbar brand label
-$navbar-inverse-brand-color:                #fff;
-$navbar-inverse-brand-hover-color:          #fff;
-$navbar-inverse-brand-hover-bg:             transparent;
+$navbar-inverse-brand-color:                #fff !default;
+$navbar-inverse-brand-hover-color:          #fff !default;
+$navbar-inverse-brand-hover-bg:             transparent !default;
 
 // Inverted navbar toggle
-$navbar-inverse-toggle-hover-bg:            $navbar-inverse-link-active-bg;
-$navbar-inverse-toggle-icon-bar-bg:         $navbar-inverse-link-color;
-$navbar-inverse-toggle-border-color:        transparent;
+$navbar-inverse-toggle-hover-bg:            $navbar-inverse-link-active-bg !default;
+$navbar-inverse-toggle-icon-bar-bg:         $navbar-inverse-link-color !default;
+$navbar-inverse-toggle-border-color:        transparent !default;
 
 
 //== Navs
@@ -414,97 +414,97 @@ $navbar-inverse-toggle-border-color:        transparent;
 //##
 
 //=== Shared nav styles
-$nav-link-padding:                          10px 15px;
-$nav-link-hover-bg:                         $gray-lighter;
+$nav-link-padding:                          10px 15px !default;
+$nav-link-hover-bg:                         $gray-lighter !default;
 
-$nav-disabled-link-color:                   $gray-light;
-$nav-disabled-link-hover-color:             $gray-light;
+$nav-disabled-link-color:                   $gray-light !default;
+$nav-disabled-link-hover-color:             $gray-light !default;
 
 //== Tabs
-$nav-tabs-border-color:                     $gray-light;
+$nav-tabs-border-color:                     $gray-light !default;
 
-$nav-tabs-link-hover-border-color:          $gray-light;
+$nav-tabs-link-hover-border-color:          $gray-light !default;
 
-$nav-tabs-active-link-hover-bg:             $body-bg;
-$nav-tabs-active-link-hover-color:          $gray;
-$nav-tabs-active-link-hover-border-color:   $gray-light;
+$nav-tabs-active-link-hover-bg:             $body-bg !default;
+$nav-tabs-active-link-hover-color:          $gray !default;
+$nav-tabs-active-link-hover-border-color:   $gray-light !default;
 
-$nav-tabs-justified-link-border-color:            $gray-light;
-$nav-tabs-justified-active-link-border-color:     $body-bg;
+$nav-tabs-justified-link-border-color:            $gray-light !default;
+$nav-tabs-justified-active-link-border-color:     $body-bg !default;
 
 //== Pills
-$nav-pills-border-radius:                   $border-radius-base;
-$nav-pills-active-link-hover-bg:            $component-active-bg;
-$nav-pills-active-link-hover-color:         $component-active-color;
+$nav-pills-border-radius:                   $border-radius-base !default;
+$nav-pills-active-link-hover-bg:            $component-active-bg !default;
+$nav-pills-active-link-hover-color:         $component-active-color !default;
 
 
 //== Pagination
 //
 //##
 
-$pagination-color:                     $gray;
-$pagination-bg:                        $gray-lighter;
-$pagination-border:                    $gray-light;
+$pagination-color:                     $gray !default;
+$pagination-bg:                        $gray-lighter !default;
+$pagination-border:                    $gray-light !default;
 
-$pagination-hover-color:               $gray-dark;
-$pagination-hover-bg:                  $gray-light;
-$pagination-hover-border:              $pagination-border;
+$pagination-hover-color:               $gray-dark !default;
+$pagination-hover-bg:                  $gray-light !default;
+$pagination-hover-border:              $pagination-border !default;
 
-$pagination-active-color:              $gray-dark;
-$pagination-active-bg:                 $gray-light;
-$pagination-active-border:             $gray-light;
+$pagination-active-color:              $gray-dark !default;
+$pagination-active-bg:                 $gray-light !default;
+$pagination-active-border:             $gray-light !default;
 
-$pagination-disabled-color:            $gray-light;
-$pagination-disabled-bg:               $gray-lighter;
-$pagination-disabled-border:           $gray-light;
+$pagination-disabled-color:            $gray-light !default;
+$pagination-disabled-bg:               $gray-lighter !default;
+$pagination-disabled-border:           $gray-light !default;
 
 
 //== Pager
 //
 //##
 
-$pager-bg:                             $pagination-bg;
-$pager-border:                         $pagination-border;
-$pager-border-radius:                  15px;
+$pager-bg:                             $pagination-bg !default;
+$pager-border:                         $pagination-border !default;
+$pager-border-radius:                  15px !default;
 
-$pager-hover-bg:                       $pagination-hover-bg;
+$pager-hover-bg:                       $pagination-hover-bg !default;
 
-$pager-active-bg:                      $pagination-active-bg;
-$pager-active-color:                   $pagination-active-color;
+$pager-active-bg:                      $pagination-active-bg !default;
+$pager-active-color:                   $pagination-active-color !default;
 
-$pager-disabled-color:                 $pagination-disabled-color;
+$pager-disabled-color:                 $pagination-disabled-color !default;
 
 
 //== Jumbotron
 //
 //##
 
-$jumbotron-padding:              30px;
-$jumbotron-color:                inherit;
-$jumbotron-bg:                   $gray-lighter;
-$jumbotron-heading-color:        inherit;
-$jumbotron-font-size:            ceil(($font-size-base * 1.5));
+$jumbotron-padding:              30px !default;
+$jumbotron-color:                inherit !default;
+$jumbotron-bg:                   $gray-lighter !default;
+$jumbotron-heading-color:        inherit !default;
+$jumbotron-font-size:            ceil(($font-size-base * 1.5)) !default;
 
 
 //== Form states and alerts
 //
 //## Define colors for form feedback states and, by default, alerts.
 
-$state-success-text:             $brand-success;
-$state-success-bg:               #dff0d8;
-$state-success-border:           darken(adjust-hue($state-success-bg, -10), 5%);
+$state-success-text:             $brand-success !default;
+$state-success-bg:               #dff0d8 !default;
+$state-success-border:           darken(adjust-hue($state-success-bg, -10), 5%) !default;
 
-$state-info-text:                $brand-info;
-$state-info-bg:                  #d9edf7;
-$state-info-border:              darken(adjust-hue($state-info-bg, -10), 7%);
+$state-info-text:                $brand-info !default;
+$state-info-bg:                  #d9edf7 !default;
+$state-info-border:              darken(adjust-hue($state-info-bg, -10), 7%) !default;
 
-$state-warning-text:             $brand-warning;
-$state-warning-bg:               #fcf8e3;
-$state-warning-border:           darken(adjust-hue($state-warning-bg, -10), 5%);
+$state-warning-text:             $brand-warning !default;
+$state-warning-bg:               #fcf8e3 !default;
+$state-warning-border:           darken(adjust-hue($state-warning-bg, -10), 5%) !default;
 
-$state-danger-text:              $brand-danger;
-$state-danger-bg:                #f2dede;
-$state-danger-border:            darken(adjust-hue($state-danger-bg, -10), 5%);
+$state-danger-text:              $brand-danger !default;
+$state-danger-bg:                #f2dede !default;
+$state-danger-border:            darken(adjust-hue($state-danger-bg, -10), 5%) !default;
 
 
 //== Tooltips
@@ -512,17 +512,17 @@ $state-danger-border:            darken(adjust-hue($state-danger-bg, -10), 5%);
 //##
 
 //** Tooltip max width
-$tooltip-max-width:           200px;
+$tooltip-max-width:           200px !default;
 //** Tooltip text color
-$tooltip-color:               #fff;
+$tooltip-color:               #fff !default;
 //** Tooltip background color
-$tooltip-bg:                  $navbar-default-bg;
-$tooltip-opacity:             1;
+$tooltip-bg:                  $navbar-default-bg !default;
+$tooltip-opacity:             1 !default;
 
 //** Tooltip arrow width
-$tooltip-arrow-width:         5px;
+$tooltip-arrow-width:         5px !default;
 //** Tooltip arrow color
-$tooltip-arrow-color:         $tooltip-bg;
+$tooltip-arrow-color:         $tooltip-bg !default;
 
 
 //== Popovers
@@ -530,28 +530,28 @@ $tooltip-arrow-color:         $tooltip-bg;
 //##
 
 //** Popover body background color
-$popover-bg:                          #fff;
+$popover-bg:                          #fff !default;
 //** Popover maximum width
-$popover-max-width:                   276px;
+$popover-max-width:                   276px !default;
 //** Popover border color
-$popover-border-color:                $gray-light;
+$popover-border-color:                $gray-light !default;
 //** Popover fallback border color
-$popover-fallback-border-color:       $gray-light;
+$popover-fallback-border-color:       $gray-light !default;
 
 //** Popover title background color
-$popover-title-bg:                    $gray-lighter;
+$popover-title-bg:                    $gray-lighter !default;
 
 //** Popover arrow width
-$popover-arrow-width:                 10px;
+$popover-arrow-width:                 10px !default;
 //** Popover arrow color
-$popover-arrow-color:                 $popover-bg;
+$popover-arrow-color:                 $popover-bg !default;
 
 //** Popover outer arrow width
-$popover-arrow-outer-width:           ($popover-arrow-width + 1);
+$popover-arrow-outer-width:           ($popover-arrow-width + 1) !default;
 //** Popover outer arrow color
-$popover-arrow-outer-color:           fadein($popover-border-color, 5%);
+$popover-arrow-outer-color:           fadein($popover-border-color, 5%) !default;
 //** Popover outer arrow fallback color
-$popover-arrow-outer-fallback-color:  darken($popover-fallback-border-color, 20%);
+$popover-arrow-outer-fallback-color:  darken($popover-fallback-border-color, 20%) !default;
 
 
 //== Labels
@@ -559,22 +559,22 @@ $popover-arrow-outer-fallback-color:  darken($popover-fallback-border-color, 20%
 //##
 
 //** Default label background color
-$label-default-bg:            $navbar-default-bg;
+$label-default-bg:            $navbar-default-bg !default;
 //** Primary label background color
-$label-primary-bg:            $brand-primary;
+$label-primary-bg:            $brand-primary !default;
 //** Success label background color
-$label-success-bg:            $brand-success;
+$label-success-bg:            $brand-success !default;
 //** Info label background color
-$label-info-bg:               $brand-info;
+$label-info-bg:               $brand-info !default;
 //** Warning label background color
-$label-warning-bg:            $brand-warning;
+$label-warning-bg:            $brand-warning !default;
 //** Danger label background color
-$label-danger-bg:             $brand-danger;
+$label-danger-bg:             $brand-danger !default;
 
 //** Default label text color
-$label-color:                 #fff;
+$label-color:                 #fff !default;
 //** Default text color of a linked label
-$label-link-hover-color:      #fff;
+$label-link-hover-color:      #fff !default;
 
 
 //== Modals
@@ -582,57 +582,57 @@ $label-link-hover-color:      #fff;
 //##
 
 //** Padding applied to the modal body
-$modal-inner-padding:         15px;
+$modal-inner-padding:         15px !default;
 
 //** Padding applied to the modal title
-$modal-title-padding:         15px;
+$modal-title-padding:         15px !default;
 //** Modal title line-height
-$modal-title-line-height:     $line-height-base;
+$modal-title-line-height:     $line-height-base !default;
 
 //** Background color of modal content area
-$modal-content-bg:                             #fff;
+$modal-content-bg:                             #fff !default;
 //** Modal content border color
-$modal-content-border-color:                   $gray-lighter;
+$modal-content-border-color:                   $gray-lighter !default;
 //** Modal content border color **for IE8**
-$modal-content-fallback-border-color:          $gray-lighter;
+$modal-content-fallback-border-color:          $gray-lighter !default;
 
 //** Modal backdrop background color
-$modal-backdrop-bg:           #000;
+$modal-backdrop-bg:           #000 !default;
 //** Modal backdrop opacity
-$modal-backdrop-opacity:      .5;
+$modal-backdrop-opacity:      .5 !default;
 //** Modal header border color
-$modal-header-border-color:   $gray-lighter;
+$modal-header-border-color:   $gray-lighter !default;
 //** Modal footer border color
-$modal-footer-border-color:   $modal-header-border-color;
+$modal-footer-border-color:   $modal-header-border-color !default;
 
-$modal-lg:                    900px;
-$modal-md:                    600px;
-$modal-sm:                    300px;
+$modal-lg:                    900px !default;
+$modal-md:                    600px !default;
+$modal-sm:                    300px !default;
 
 
 //== Alerts
 //
 //## Define alert colors, border radius, and padding.
 
-$alert-padding:               15px;
-$alert-border-radius:         $border-radius-base;
-$alert-link-font-weight:      bold;
+$alert-padding:               15px !default;
+$alert-border-radius:         $border-radius-base !default;
+$alert-link-font-weight:      bold !default;
 
-$alert-success-bg:            $brand-success;
-$alert-success-text:          #fff;
-$alert-success-border:        transparent;
+$alert-success-bg:            $brand-success !default;
+$alert-success-text:          #fff !default;
+$alert-success-border:        transparent !default;
 
-$alert-info-bg:               $brand-info;
-$alert-info-text:             #fff;
-$alert-info-border:           transparent;
+$alert-info-bg:               $brand-info !default;
+$alert-info-text:             #fff !default;
+$alert-info-border:           transparent !default;
 
-$alert-warning-bg:            $brand-warning;
-$alert-warning-text:          #fff;
-$alert-warning-border:        transparent;
+$alert-warning-bg:            $brand-warning !default;
+$alert-warning-text:          #fff !default;
+$alert-warning-border:        transparent !default;
 
-$alert-danger-bg:             $brand-danger;
-$alert-danger-text:           #fff;
-$alert-danger-border:         transparent;
+$alert-danger-bg:             $brand-danger !default;
+$alert-danger-text:           #fff !default;
+$alert-danger-border:         transparent !default;
 
 
 //== Progress bars
@@ -640,22 +640,22 @@ $alert-danger-border:         transparent;
 //##
 
 //** Background color of the whole progress component
-$progress-bg:                 #f5f5f5;
+$progress-bg:                 #f5f5f5 !default;
 //** Progress bar text color
-$progress-bar-color:          #fff;
+$progress-bar-color:          #fff !default;
 //** Variable for setting rounded corners on progress bar.
-$progress-border-radius:      $border-radius-base;
+$progress-border-radius:      $border-radius-base !default;
 
 //** Default progress bar color
-$progress-bar-bg:             $brand-primary;
+$progress-bar-bg:             $brand-primary !default;
 //** Success progress bar color
-$progress-bar-success-bg:     $brand-success;
+$progress-bar-success-bg:     $brand-success !default;
 //** Warning progress bar color
-$progress-bar-warning-bg:     $brand-warning;
+$progress-bar-warning-bg:     $brand-warning !default;
 //** Danger progress bar color
-$progress-bar-danger-bg:      $brand-danger;
+$progress-bar-danger-bg:      $brand-danger !default;
 //** Info progress bar color
-$progress-bar-info-bg:        $brand-info;
+$progress-bar-info-bg:        $brand-info !default;
 
 
 //== List group
@@ -663,72 +663,72 @@ $progress-bar-info-bg:        $brand-info;
 //##
 
 //** Background color on `.list-group-item`
-$list-group-bg:                 #fff;
+$list-group-bg:                 #fff !default;
 //** `.list-group-item` border color
-$list-group-border:             $gray-light;
+$list-group-border:             $gray-light !default;
 //** List group border radius
-$list-group-border-radius:      $border-radius-base;
+$list-group-border-radius:      $border-radius-base !default;
 
 //** Background color of single list items on hover
-$list-group-hover-bg:           $gray-lighter;
+$list-group-hover-bg:           $gray-lighter !default;
 //** Text color of active list items
-$list-group-active-color:       $text-color;
+$list-group-active-color:       $text-color !default;
 //** Background color of active list items
-$list-group-active-bg:          $component-active-bg;
+$list-group-active-bg:          $component-active-bg !default;
 //** Border color of active list elements
-$list-group-active-border:      $list-group-border;
+$list-group-active-border:      $list-group-border !default;
 //** Text color for content within active list items
-$list-group-active-text-color:  $text-color;
+$list-group-active-text-color:  $text-color !default;
 
 //** Text color of disabled list items
-$list-group-disabled-color:      $gray-light;
+$list-group-disabled-color:      $gray-light !default;
 //** Background color of disabled list items
-$list-group-disabled-bg:         $gray-lighter;
+$list-group-disabled-bg:         $gray-lighter !default;
 //** Text color for content within disabled list items
-$list-group-disabled-text-color: $list-group-disabled-color;
+$list-group-disabled-text-color: $list-group-disabled-color !default;
 
-$list-group-link-color:         $text-color;
-$list-group-link-hover-color:   $list-group-link-color;
-$list-group-link-heading-color: $headings-color;
+$list-group-link-color:         $text-color !default;
+$list-group-link-hover-color:   $list-group-link-color !default;
+$list-group-link-heading-color: $headings-color !default;
 
 
 //== Panels
 //
 //##
 
-$panel-bg:                    #fff;
-$panel-body-padding:          15px;
-$panel-heading-padding:       10px 15px;
-$panel-footer-padding:        $panel-heading-padding;
-$panel-border-radius:         $border-radius-base;
+$panel-bg:                    #fff !default;
+$panel-body-padding:          15px !default;
+$panel-heading-padding:       10px 15px !default;
+$panel-footer-padding:        $panel-heading-padding !default;
+$panel-border-radius:         $border-radius-base !default;
 
 //** Border color for elements within panels
-$panel-inner-border:          $gray-light;
-$panel-footer-bg:             $gray-lighter;
+$panel-inner-border:          $gray-light !default;
+$panel-footer-bg:             $gray-lighter !default;
 
-$panel-default-text:          $text-color;
-$panel-default-border:        $gray-light;
-$panel-default-heading-bg:    $gray-lighter;
+$panel-default-text:          $text-color !default;
+$panel-default-border:        $gray-light !default;
+$panel-default-heading-bg:    $gray-lighter !default;
 
-$panel-primary-text:          #fff;
-$panel-primary-border:        $brand-primary;
-$panel-primary-heading-bg:    $brand-primary;
+$panel-primary-text:          #fff !default;
+$panel-primary-border:        $brand-primary !default;
+$panel-primary-heading-bg:    $brand-primary !default;
 
-$panel-success-text:          $state-success-text;
-$panel-success-border:        $state-success-border;
-$panel-success-heading-bg:    $brand-success;
+$panel-success-text:          $state-success-text !default;
+$panel-success-border:        $state-success-border !default;
+$panel-success-heading-bg:    $brand-success !default;
 
-$panel-info-text:             $state-info-text;
-$panel-info-border:           $state-info-border;
-$panel-info-heading-bg:       $brand-info;
+$panel-info-text:             $state-info-text !default;
+$panel-info-border:           $state-info-border !default;
+$panel-info-heading-bg:       $brand-info !default;
 
-$panel-warning-text:          $state-warning-text;
-$panel-warning-border:        $state-warning-border;
-$panel-warning-heading-bg:    $brand-warning;
+$panel-warning-text:          $state-warning-text !default;
+$panel-warning-border:        $state-warning-border !default;
+$panel-warning-heading-bg:    $brand-warning !default;
 
-$panel-danger-text:           $state-danger-text;
-$panel-danger-border:         $state-danger-border;
-$panel-danger-heading-bg:     $brand-danger;
+$panel-danger-text:           $state-danger-text !default;
+$panel-danger-border:         $state-danger-border !default;
+$panel-danger-heading-bg:     $brand-danger !default;
 
 
 //== Thumbnails
@@ -736,103 +736,103 @@ $panel-danger-heading-bg:     $brand-danger;
 //##
 
 //** Padding around the thumbnail image
-$thumbnail-padding:           4px;
+$thumbnail-padding:           4px !default;
 //** Thumbnail background color
-$thumbnail-bg:                $gray-lighter;
+$thumbnail-bg:                $gray-lighter !default;
 //** Thumbnail border color
-$thumbnail-border:            $gray-light;
+$thumbnail-border:            $gray-light !default;
 //** Thumbnail border radius
-$thumbnail-border-radius:     $border-radius-base;
+$thumbnail-border-radius:     $border-radius-base !default;
 
 //** Custom text color for thumbnail captions
-$thumbnail-caption-color:     $text-color;
+$thumbnail-caption-color:     $text-color !default;
 //** Padding around the thumbnail caption
-$thumbnail-caption-padding:   9px;
+$thumbnail-caption-padding:   9px !default;
 
 
 //== Wells
 //
 //##
 
-$well-bg:                     $gray-lighter;
-$well-border:                 transparent;
+$well-bg:                     $gray-lighter !default;
+$well-border:                 transparent !default;
 
 
 //== Badges
 //
 //##
 
-$badge-color:                 #fff;
+$badge-color:                 #fff !default;
 //** Linked badge text color on hover
-$badge-link-hover-color:      #fff;
-$badge-bg:                    $brand-success;
+$badge-link-hover-color:      #fff !default;
+$badge-bg:                    $brand-success !default;
 
 //** Badge text color in active nav link
-$badge-active-color:          #fff;
+$badge-active-color:          #fff !default;
 //** Badge background color in active nav link
-$badge-active-bg:             $brand-success;
+$badge-active-bg:             $brand-success !default;
 
-$badge-font-weight:           normal;
-$badge-line-height:           1;
-$badge-border-radius:         10px;
+$badge-font-weight:           normal !default;
+$badge-line-height:           1 !default;
+$badge-border-radius:         10px !default;
 
 
 //== Breadcrumbs
 //
 //##
 
-$breadcrumb-padding-vertical:   8px;
-$breadcrumb-padding-horizontal: 15px;
+$breadcrumb-padding-vertical:   8px !default;
+$breadcrumb-padding-horizontal: 15px !default;
 //** Breadcrumb background color
-$breadcrumb-bg:                 $gray-lighter;
+$breadcrumb-bg:                 $gray-lighter !default;
 //** Breadcrumb text color
-$breadcrumb-color:              $gray-light;
+$breadcrumb-color:              $gray-light !default;
 //** Text color of current page in the breadcrumb
-$breadcrumb-active-color:       $gray;
+$breadcrumb-active-color:       $gray !default;
 //** Textual separator for between breadcrumb elements
-$breadcrumb-separator:          "/";
+$breadcrumb-separator:          "/" !default;
 
 
 //== Carousel
 //
 //##
 
-$carousel-text-shadow:                        0 1px 2px rgba(0,0,0,.6);
+$carousel-text-shadow:                        0 1px 2px rgba(0,0,0,.6) !default;
 
-$carousel-control-color:                      #fff;
-$carousel-control-width:                      15%;
-$carousel-control-opacity:                    .5;
-$carousel-control-font-size:                  20px;
+$carousel-control-color:                      #fff !default;
+$carousel-control-width:                      15% !default;
+$carousel-control-opacity:                    .5 !default;
+$carousel-control-font-size:                  20px !default;
 
-$carousel-indicator-active-bg:                #fff;
-$carousel-indicator-border-color:             #fff;
+$carousel-indicator-active-bg:                #fff !default;
+$carousel-indicator-border-color:             #fff !default;
 
-$carousel-caption-color:                      #fff;
+$carousel-caption-color:                      #fff !default;
 
 
 //== Close
 //
 //##
 
-$close-font-weight:           bold;
-$close-color:                 #000;
-$close-text-shadow:           0 0 0 transparent;
+$close-font-weight:           bold !default;
+$close-color:                 #000 !default;
+$close-text-shadow:           0 0 0 transparent !default;
 
 
 //== Code
 //
 //##
 
-$code-color:                  #c7254e;
-$code-bg:                     #f9f2f4;
+$code-color:                  #c7254e !default;
+$code-bg:                     #f9f2f4 !default;
 
-$kbd-color:                   #fff;
-$kbd-bg:                      #333;
+$kbd-color:                   #fff !default;
+$kbd-bg:                      #333 !default;
 
-$pre-bg:                      #f5f5f5;
-$pre-color:                   $gray-dark;
-$pre-border-color:            #ccc;
-$pre-scrollable-max-height:   340px;
+$pre-bg:                      #f5f5f5 !default;
+$pre-color:                   $gray-dark !default;
+$pre-border-color:            #ccc !default;
+$pre-scrollable-max-height:   340px !default;
 
 
 //== Type
@@ -840,22 +840,22 @@ $pre-scrollable-max-height:   340px;
 //##
 
 //** Horizontal offset for forms and lists.
-$component-offset-horizontal: 180px;
+$component-offset-horizontal: 180px !default;
 //** Text muted color
-$text-muted:                  $gray;
+$text-muted:                  $gray !default;
 //** Abbreviations and acronyms border color
-$abbr-border-color:           $gray;
+$abbr-border-color:           $gray !default;
 //** Headings small color
-$headings-small-color:        $gray;
+$headings-small-color:        $gray !default;
 //** Blockquote small color
-$blockquote-small-color:      $text-color;
+$blockquote-small-color:      $text-color !default;
 //** Blockquote font size
-$blockquote-font-size:        ($font-size-base * 1.25);
+$blockquote-font-size:        ($font-size-base * 1.25) !default;
 //** Blockquote border color
-$blockquote-border-color:     $gray-light;
+$blockquote-border-color:     $gray-light !default;
 //** Page header border color
-$page-header-border-color:    $gray-lighter;
+$page-header-border-color:    $gray-lighter !default;
 //** Width of horizontal description list titles
-$dl-horizontal-offset:        $component-offset-horizontal;
+$dl-horizontal-offset:        $component-offset-horizontal !default;
 //** Horizontal line color.
-$hr-border:                   $gray-lighter;
+$hr-border:                   $gray-lighter !default;
diff --git a/simplex/_variables.scss b/simplex/_variables.scss
index 5e416b56..d6bd5bc7 100644
--- a/simplex/_variables.scss
+++ b/simplex/_variables.scss
@@ -7,18 +7,18 @@
 //
 //## Gray and brand colors for use across Bootstrap.
 
-$gray-base:              #000;
-$gray-darker:            lighten($gray-base, 13.5%); // #222
-$gray-dark:              #444;
-$gray:                   #777;
-$gray-light:             #808080;
-$gray-lighter:           #ddd;
+$gray-base:              #000 !default;
+$gray-darker:            lighten($gray-base, 13.5%) !default; // #222
+$gray-dark:              #444 !default;
+$gray:                   #777 !default;
+$gray-light:             #808080 !default;
+$gray-lighter:           #ddd !default;
 
-$brand-primary:         #D9230F;
-$brand-success:         #469408;
-$brand-info:            #029ACF;
-$brand-warning:         #9B479F;
-$brand-danger:          #D9831F;
+$brand-primary:         #D9230F !default;
+$brand-success:         #469408 !default;
+$brand-info:            #029ACF !default;
+$brand-warning:         #9B479F !default;
+$brand-danger:          #D9831F !default;
 
 
 //== Scaffolding
@@ -26,49 +26,49 @@ $brand-danger:          #D9831F;
 //## Settings for some of the most global styles.
 
 //** Background color for ``.
-$body-bg:               #FCFCFC;
+$body-bg:               #FCFCFC !default;
 //** Global text color on ``.
-$text-color:            $gray;
+$text-color:            $gray !default;
 
 //** Global textual link color.
-$link-color:            $brand-primary;
+$link-color:            $brand-primary !default;
 //** Link hover color set via `darken()` function.
-$link-hover-color:      darken($link-color, 15%);
+$link-hover-color:      darken($link-color, 15%) !default;
 //** Link hover decoration.
-$link-hover-decoration: underline;
+$link-hover-decoration: underline !default;
 
 
 //== Typography
 //
 //## Font, line-height, and color for body text, headings, and more.
 
-$font-family-sans-serif:  "Open Sans", "Helvetica Neue", Helvetica, Arial, sans-serif;
-$font-family-serif:       Georgia, "Times New Roman", Times, serif;
+$font-family-sans-serif:  "Open Sans", "Helvetica Neue", Helvetica, Arial, sans-serif !default;
+$font-family-serif:       Georgia, "Times New Roman", Times, serif !default;
 //** Default monospace fonts for ``, ``, and `
`.
-$font-family-monospace:   Menlo, Monaco, Consolas, "Courier New", monospace;
-$font-family-base:        $font-family-sans-serif;
+$font-family-monospace:   Menlo, Monaco, Consolas, "Courier New", monospace !default;
+$font-family-base:        $font-family-sans-serif !default;
 
-$font-size-base:          13px;
-$font-size-large:         ceil(($font-size-base * 1.25)); // ~18px
-$font-size-small:         ceil(($font-size-base * 0.85)); // ~12px
+$font-size-base:          13px !default;
+$font-size-large:         ceil(($font-size-base * 1.25)) !default; // ~18px
+$font-size-small:         ceil(($font-size-base * 0.85)) !default; // ~12px
 
-$font-size-h1:            floor(($font-size-base * 2.6)); // ~36px
-$font-size-h2:            floor(($font-size-base * 2.15)); // ~30px
-$font-size-h3:            ceil(($font-size-base * 1.7)); // ~24px
-$font-size-h4:            ceil(($font-size-base * 1.25)); // ~18px
-$font-size-h5:            $font-size-base;
-$font-size-h6:            ceil(($font-size-base * 0.85)); // ~12px
+$font-size-h1:            floor(($font-size-base * 2.6)) !default; // ~36px
+$font-size-h2:            floor(($font-size-base * 2.15)) !default; // ~30px
+$font-size-h3:            ceil(($font-size-base * 1.7)) !default; // ~24px
+$font-size-h4:            ceil(($font-size-base * 1.25)) !default; // ~18px
+$font-size-h5:            $font-size-base !default;
+$font-size-h6:            ceil(($font-size-base * 0.85)) !default; // ~12px
 
 //** Unit-less `line-height` for use in components like buttons.
-$line-height-base:        1.428571429; // 20/14
+$line-height-base:        1.428571429 !default; // 20/14
 //** Computed "line-height" (`font-size` * `line-height`) for use with `margin`, `padding`, etc.
-$line-height-computed:    floor(($font-size-base * $line-height-base)); // ~20px
+$line-height-computed:    floor(($font-size-base * $line-height-base)) !default; // ~20px
 
 //** By default, this inherits from the ``.
-$headings-font-family:    $font-family-sans-serif;
-$headings-font-weight:    300;
-$headings-line-height:    1.1;
-$headings-color:          $gray-dark;
+$headings-font-family:    $font-family-sans-serif !default;
+$headings-font-weight:    300 !default;
+$headings-line-height:    1.1 !default;
+$headings-color:          $gray-dark !default;
 
 
 //== Iconography
@@ -76,45 +76,45 @@ $headings-color:          $gray-dark;
 //## Specify custom location and filename of the included Glyphicons icon font. Useful for those including Bootstrap via Bower.
 
 //** Load fonts from this directory.
-$icon-font-path:          "../fonts/";
+$icon-font-path:          "../fonts/" !default;
 //** File name for all font files.
-$icon-font-name:          "glyphicons-halflings-regular";
+$icon-font-name:          "glyphicons-halflings-regular" !default;
 //** Element ID within SVG icon file.
-$icon-font-svg-id:        "glyphicons_halflingsregular";
+$icon-font-svg-id:        "glyphicons_halflingsregular" !default;
 
 
 //== Components
 //
 //## Define common padding and border radius sizes and more. Values based on 14px text and 1.428 line-height (~20px to start).
 
-$padding-base-vertical:     8px;
-$padding-base-horizontal:   12px;
+$padding-base-vertical:     8px !default;
+$padding-base-horizontal:   12px !default;
 
-$padding-large-vertical:    14px;
-$padding-large-horizontal:  16px;
+$padding-large-vertical:    14px !default;
+$padding-large-horizontal:  16px !default;
 
-$padding-small-vertical:    5px;
-$padding-small-horizontal:  10px;
+$padding-small-vertical:    5px !default;
+$padding-small-horizontal:  10px !default;
 
-$padding-xs-vertical:       1px;
-$padding-xs-horizontal:     5px;
+$padding-xs-vertical:       1px !default;
+$padding-xs-horizontal:     5px !default;
 
-$line-height-large:         1.3333333; // extra decimals for Win 8.1 Chrome
-$line-height-small:         1.5;
+$line-height-large:         1.3333333 !default; // extra decimals for Win 8.1 Chrome
+$line-height-small:         1.5 !default;
 
-$border-radius-base:        4px;
-$border-radius-large:       6px;
-$border-radius-small:       3px;
+$border-radius-base:        4px !default;
+$border-radius-large:       6px !default;
+$border-radius-small:       3px !default;
 
 //** Global color for active items (e.g., navs or dropdowns).
-$component-active-color:    #fff;
+$component-active-color:    #fff !default;
 //** Global background color for active items (e.g., navs or dropdowns).
-$component-active-bg:       $brand-primary;
+$component-active-bg:       $brand-primary !default;
 
 //** Width of the `border` for generating carets that indicator dropdowns.
-$caret-width-base:          4px;
+$caret-width-base:          4px !default;
 //** Carets increase slightly in size for larger components.
-$caret-width-large:         5px;
+$caret-width-large:         5px !default;
 
 
 //== Tables
@@ -122,53 +122,53 @@ $caret-width-large:         5px;
 //## Customizes the `.table` component with basic values, each used across all table variations.
 
 //** Padding for ``s and ``s.
-$table-cell-padding:            8px;
+$table-cell-padding:            8px !default;
 //** Padding for cells in `.table-condensed`.
-$table-condensed-cell-padding:  5px;
+$table-condensed-cell-padding:  5px !default;
 
 //** Default background color used for all tables.
-$table-bg:                      transparent;
+$table-bg:                      transparent !default;
 //** Background color used for `.table-striped`.
-$table-bg-accent:               #f9f9f9;
+$table-bg-accent:               #f9f9f9 !default;
 //** Background color used for `.table-hover`.
-$table-bg-hover:                #f5f5f5;
-$table-bg-active:               $table-bg-hover;
+$table-bg-hover:                #f5f5f5 !default;
+$table-bg-active:               $table-bg-hover !default;
 
 //** Border color for table and cell borders.
-$table-border-color:            #ddd;
+$table-border-color:            #ddd !default;
 
 
 //== Buttons
 //
 //## For each of Bootstrap's buttons, define text, background and border color.
 
-$btn-font-weight:                normal;
+$btn-font-weight:                normal !default;
 
-$btn-default-color:              #fff;
-$btn-default-bg:                 #474949;
-$btn-default-border:             $btn-default-bg;
+$btn-default-color:              #fff !default;
+$btn-default-bg:                 #474949 !default;
+$btn-default-border:             $btn-default-bg !default;
 
-$btn-primary-color:              $btn-default-color;
-$btn-primary-bg:                 $brand-primary;
-$btn-primary-border:             $btn-primary-bg;
+$btn-primary-color:              $btn-default-color !default;
+$btn-primary-bg:                 $brand-primary !default;
+$btn-primary-border:             $btn-primary-bg !default;
 
-$btn-success-color:              $btn-default-color;
-$btn-success-bg:                 $brand-success;
-$btn-success-border:             $btn-success-bg;
+$btn-success-color:              $btn-default-color !default;
+$btn-success-bg:                 $brand-success !default;
+$btn-success-border:             $btn-success-bg !default;
 
-$btn-info-color:                 $btn-default-color;
-$btn-info-bg:                    $brand-info;
-$btn-info-border:                $btn-info-bg;
+$btn-info-color:                 $btn-default-color !default;
+$btn-info-bg:                    $brand-info !default;
+$btn-info-border:                $btn-info-bg !default;
 
-$btn-warning-color:              $btn-default-color;
-$btn-warning-bg:                 $brand-warning;
-$btn-warning-border:             $btn-warning-bg;
+$btn-warning-color:              $btn-default-color !default;
+$btn-warning-bg:                 $brand-warning !default;
+$btn-warning-border:             $btn-warning-bg !default;
 
-$btn-danger-color:               $btn-default-color;
-$btn-danger-bg:                  $brand-danger;
-$btn-danger-border:              $btn-danger-bg;
+$btn-danger-color:               $btn-default-color !default;
+$btn-danger-bg:                  $brand-danger !default;
+$btn-danger-border:              $btn-danger-bg !default;
 
-$btn-link-disabled-color:        $gray-light;
+$btn-link-disabled-color:        $gray-light !default;
 
 
 //== Forms
@@ -176,50 +176,50 @@ $btn-link-disabled-color:        $gray-light;
 //##
 
 //** `` background color
-$input-bg:                       #fff;
+$input-bg:                       #fff !default;
 //** `` background color
-$input-bg-disabled:              $gray-lighter;
+$input-bg-disabled:              $gray-lighter !default;
 
 //** Text color for ``s
-$input-color:                    $text-color;
+$input-color:                    $text-color !default;
 //** `` border color
-$input-border:                   #ddd;
+$input-border:                   #ddd !default;
 
 // TODO: Rename `$input-border-radius` to `$input-border-radius-base` in v4
 //** Default `.form-control` border radius
 // This has no effect on ``s in CSS.
-$input-border-radius:            $border-radius-base;
+$input-border-radius:            $border-radius-base !default;
 //** Large `.form-control` border radius
-$input-border-radius-large:      $border-radius-large;
+$input-border-radius-large:      $border-radius-large !default;
 //** Small `.form-control` border radius
-$input-border-radius-small:      $border-radius-small;
+$input-border-radius-small:      $border-radius-small !default;
 
 //** Border color for inputs on focus
-$input-border-focus:             #66afe9;
+$input-border-focus:             #66afe9 !default;
 
 //** Placeholder text color
-$input-color-placeholder:        $gray-lighter;
+$input-color-placeholder:        $gray-lighter !default;
 
 //** Default `.form-control` height
-$input-height-base:              ($line-height-computed + ($padding-base-vertical * 2) + 2);
+$input-height-base:              ($line-height-computed + ($padding-base-vertical * 2) + 2) !default;
 //** Large `.form-control` height
-$input-height-large:             (ceil($font-size-large * $line-height-large) + ($padding-large-vertical * 2) + 2);
+$input-height-large:             (ceil($font-size-large * $line-height-large) + ($padding-large-vertical * 2) + 2) !default;
 //** Small `.form-control` height
-$input-height-small:             (floor($font-size-small * $line-height-small) + ($padding-small-vertical * 2) + 2);
+$input-height-small:             (floor($font-size-small * $line-height-small) + ($padding-small-vertical * 2) + 2) !default;
 
 //** `.form-group` margin
-$form-group-margin-bottom:       15px;
+$form-group-margin-bottom:       15px !default;
 
-$legend-color:                   $text-color;
-$legend-border-color:            #e5e5e5;
+$legend-color:                   $text-color !default;
+$legend-border-color:            #e5e5e5 !default;
 
 //** Background color for textual input addons
-$input-group-addon-bg:           $gray-lighter;
+$input-group-addon-bg:           $gray-lighter !default;
 //** Border color for textual input addons
-$input-group-addon-border-color: $input-border;
+$input-group-addon-border-color: $input-border !default;
 
 //** Disabled cursor for form controls and buttons.
-$cursor-disabled:                not-allowed;
+$cursor-disabled:                not-allowed !default;
 
 
 //== Dropdowns
@@ -227,34 +227,34 @@ $cursor-disabled:                not-allowed;
 //## Dropdown menu container and contents.
 
 //** Background for the dropdown menu.
-$dropdown-bg:                    #fff;
+$dropdown-bg:                    #fff !default;
 //** Dropdown menu `border-color`.
-$dropdown-border:                rgba(0,0,0,.15);
+$dropdown-border:                rgba(0,0,0,.15) !default;
 //** Dropdown menu `border-color` **for IE8**.
-$dropdown-fallback-border:       #ccc;
+$dropdown-fallback-border:       #ccc !default;
 //** Divider color for between dropdown items.
-$dropdown-divider-bg:            #e5e5e5;
+$dropdown-divider-bg:            #e5e5e5 !default;
 
 //** Dropdown link text color.
-$dropdown-link-color:            $gray-dark;
+$dropdown-link-color:            $gray-dark !default;
 //** Hover color for dropdown links.
-$dropdown-link-hover-color:      #fff;
+$dropdown-link-hover-color:      #fff !default;
 //** Hover background for dropdown links.
-$dropdown-link-hover-bg:         $component-active-bg;
+$dropdown-link-hover-bg:         $component-active-bg !default;
 
 //** Active dropdown menu item text color.
-$dropdown-link-active-color:     #fff;
+$dropdown-link-active-color:     #fff !default;
 //** Active dropdown menu item background color.
-$dropdown-link-active-bg:        $component-active-bg;
+$dropdown-link-active-bg:        $component-active-bg !default;
 
 //** Disabled dropdown menu item background color.
-$dropdown-link-disabled-color:   $gray-light;
+$dropdown-link-disabled-color:   $gray-light !default;
 
 //** Text color for headers within dropdown menus.
-$dropdown-header-color:          $gray-light;
+$dropdown-header-color:          $gray-light !default;
 
 //** Deprecated `$dropdown-caret-color` as of v3.1.0
-$dropdown-caret-color:           #000;
+$dropdown-caret-color:           #000 !default;
 
 
 //-- Z-index master list
@@ -264,13 +264,13 @@ $dropdown-caret-color:           #000;
 //
 // Note: These variables are not generated into the Customizer.
 
-$zindex-navbar:            1000;
-$zindex-dropdown:          1000;
-$zindex-popover:           1060;
-$zindex-tooltip:           1070;
-$zindex-navbar-fixed:      1030;
-$zindex-modal-background:  1040;
-$zindex-modal:             1050;
+$zindex-navbar:            1000 !default;
+$zindex-dropdown:          1000 !default;
+$zindex-popover:           1060 !default;
+$zindex-tooltip:           1070 !default;
+$zindex-navbar-fixed:      1030 !default;
+$zindex-modal-background:  1040 !default;
+$zindex-modal:             1050 !default;
 
 
 //== Media queries breakpoints
@@ -279,37 +279,37 @@ $zindex-modal:             1050;
 
 // Extra small screen / phone
 //** Deprecated `$screen-xs` as of v3.0.1
-$screen-xs:                  480px;
+$screen-xs:                  480px !default;
 //** Deprecated `$screen-xs-min` as of v3.2.0
-$screen-xs-min:              $screen-xs;
+$screen-xs-min:              $screen-xs !default;
 //** Deprecated `$screen-phone` as of v3.0.1
-$screen-phone:               $screen-xs-min;
+$screen-phone:               $screen-xs-min !default;
 
 // Small screen / tablet
 //** Deprecated `$screen-sm` as of v3.0.1
-$screen-sm:                  768px;
-$screen-sm-min:              $screen-sm;
+$screen-sm:                  768px !default;
+$screen-sm-min:              $screen-sm !default;
 //** Deprecated `$screen-tablet` as of v3.0.1
-$screen-tablet:              $screen-sm-min;
+$screen-tablet:              $screen-sm-min !default;
 
 // Medium screen / desktop
 //** Deprecated `$screen-md` as of v3.0.1
-$screen-md:                  992px;
-$screen-md-min:              $screen-md;
+$screen-md:                  992px !default;
+$screen-md-min:              $screen-md !default;
 //** Deprecated `$screen-desktop` as of v3.0.1
-$screen-desktop:             $screen-md-min;
+$screen-desktop:             $screen-md-min !default;
 
 // Large screen / wide desktop
 //** Deprecated `$screen-lg` as of v3.0.1
-$screen-lg:                  1200px;
-$screen-lg-min:              $screen-lg;
+$screen-lg:                  1200px !default;
+$screen-lg-min:              $screen-lg !default;
 //** Deprecated `$screen-lg-desktop` as of v3.0.1
-$screen-lg-desktop:          $screen-lg-min;
+$screen-lg-desktop:          $screen-lg-min !default;
 
 // So media queries don't overlap when required, provide a maximum
-$screen-xs-max:              ($screen-sm-min - 1);
-$screen-sm-max:              ($screen-md-min - 1);
-$screen-md-max:              ($screen-lg-min - 1);
+$screen-xs-max:              ($screen-sm-min - 1) !default;
+$screen-sm-max:              ($screen-md-min - 1) !default;
+$screen-md-max:              ($screen-lg-min - 1) !default;
 
 
 //== Grid system
@@ -317,14 +317,14 @@ $screen-md-max:              ($screen-lg-min - 1);
 //## Define your custom responsive grid.
 
 //** Number of columns in the grid.
-$grid-columns:              12;
+$grid-columns:              12 !default;
 //** Padding between columns. Gets divided in half for the left and right.
-$grid-gutter-width:         30px;
+$grid-gutter-width:         30px !default;
 // Navbar collapse
 //** Point at which the navbar becomes uncollapsed.
-$grid-float-breakpoint:     $screen-sm-min;
+$grid-float-breakpoint:     $screen-sm-min !default;
 //** Point at which the navbar begins collapsing.
-$grid-float-breakpoint-max: ($grid-float-breakpoint - 1);
+$grid-float-breakpoint-max: ($grid-float-breakpoint - 1) !default;
 
 
 //== Container sizes
@@ -332,19 +332,19 @@ $grid-float-breakpoint-max: ($grid-float-breakpoint - 1);
 //## Define the maximum width of `.container` for different screen sizes.
 
 // Small screen / tablet
-$container-tablet:             (720px + $grid-gutter-width);
+$container-tablet:             (720px + $grid-gutter-width) !default;
 //** For `$screen-sm-min` and up.
-$container-sm:                 $container-tablet;
+$container-sm:                 $container-tablet !default;
 
 // Medium screen / desktop
-$container-desktop:            (940px + $grid-gutter-width);
+$container-desktop:            (940px + $grid-gutter-width) !default;
 //** For `$screen-md-min` and up.
-$container-md:                 $container-desktop;
+$container-md:                 $container-desktop !default;
 
 // Large screen / wide desktop
-$container-large-desktop:      (1140px + $grid-gutter-width);
+$container-large-desktop:      (1140px + $grid-gutter-width) !default;
 //** For `$screen-lg-min` and up.
-$container-lg:                 $container-large-desktop;
+$container-lg:                 $container-large-desktop !default;
 
 
 //== Navbar
@@ -352,61 +352,61 @@ $container-lg:                 $container-large-desktop;
 //##
 
 // Basics of a navbar
-$navbar-height:                    40px;
-$navbar-margin-bottom:             $line-height-computed;
-$navbar-border-radius:             $border-radius-base;
-$navbar-padding-horizontal:        floor(($grid-gutter-width / 2));
-$navbar-padding-vertical:          (($navbar-height - $line-height-computed) / 2);
-$navbar-collapse-max-height:       340px;
+$navbar-height:                    40px !default;
+$navbar-margin-bottom:             $line-height-computed !default;
+$navbar-border-radius:             $border-radius-base !default;
+$navbar-padding-horizontal:        floor(($grid-gutter-width / 2)) !default;
+$navbar-padding-vertical:          (($navbar-height - $line-height-computed) / 2) !default;
+$navbar-collapse-max-height:       340px !default;
 
-$navbar-default-color:             $gray;
-$navbar-default-bg:                #fff;
-$navbar-default-border:            darken($navbar-default-bg, 6.5%);
+$navbar-default-color:             $gray !default;
+$navbar-default-bg:                #fff !default;
+$navbar-default-border:            darken($navbar-default-bg, 6.5%) !default;
 
 // Navbar links
-$navbar-default-link-color:                $gray;
-$navbar-default-link-hover-color:          $brand-primary;
-$navbar-default-link-hover-bg:             transparent;
-$navbar-default-link-active-color:         $navbar-default-link-hover-color;
-$navbar-default-link-active-bg:            transparent;
-$navbar-default-link-disabled-color:       #444;
-$navbar-default-link-disabled-bg:          transparent;
+$navbar-default-link-color:                $gray !default;
+$navbar-default-link-hover-color:          $brand-primary !default;
+$navbar-default-link-hover-bg:             transparent !default;
+$navbar-default-link-active-color:         $navbar-default-link-hover-color !default;
+$navbar-default-link-active-bg:            transparent !default;
+$navbar-default-link-disabled-color:       #444 !default;
+$navbar-default-link-disabled-bg:          transparent !default;
 
 // Navbar brand label
-$navbar-default-brand-color:               $navbar-default-link-color;
-$navbar-default-brand-hover-color:         $navbar-default-link-hover-color;
-$navbar-default-brand-hover-bg:            transparent;
+$navbar-default-brand-color:               $navbar-default-link-color !default;
+$navbar-default-brand-hover-color:         $navbar-default-link-hover-color !default;
+$navbar-default-brand-hover-bg:            transparent !default;
 
 // Navbar toggle
-$navbar-default-toggle-hover-bg:           #ddd;
-$navbar-default-toggle-icon-bar-bg:        #ccc;
-$navbar-default-toggle-border-color:       #ddd;
+$navbar-default-toggle-hover-bg:           #ddd !default;
+$navbar-default-toggle-icon-bar-bg:        #ccc !default;
+$navbar-default-toggle-border-color:       #ddd !default;
 
 
 // Inverted navbar
 // Reset inverted navbar basics
-$navbar-inverse-color:                      lighten($brand-primary, 40%);
-$navbar-inverse-bg:                         $brand-primary;
-$navbar-inverse-border:                     darken($navbar-inverse-bg, 10%);
+$navbar-inverse-color:                      lighten($brand-primary, 40%) !default;
+$navbar-inverse-bg:                         $brand-primary !default;
+$navbar-inverse-border:                     darken($navbar-inverse-bg, 10%) !default;
 
 // Inverted navbar links
-$navbar-inverse-link-color:                 lighten($brand-primary, 40%);
-$navbar-inverse-link-hover-color:           #fff;
-$navbar-inverse-link-hover-bg:              transparent;
-$navbar-inverse-link-active-color:          $navbar-inverse-link-hover-color;
-$navbar-inverse-link-active-bg:             transparent;
-$navbar-inverse-link-disabled-color:        #ccc;
-$navbar-inverse-link-disabled-bg:           transparent;
+$navbar-inverse-link-color:                 lighten($brand-primary, 40%) !default;
+$navbar-inverse-link-hover-color:           #fff !default;
+$navbar-inverse-link-hover-bg:              transparent !default;
+$navbar-inverse-link-active-color:          $navbar-inverse-link-hover-color !default;
+$navbar-inverse-link-active-bg:             transparent !default;
+$navbar-inverse-link-disabled-color:        #ccc !default;
+$navbar-inverse-link-disabled-bg:           transparent !default;
 
 // Inverted navbar brand label
-$navbar-inverse-brand-color:                $navbar-inverse-link-color;
-$navbar-inverse-brand-hover-color:          #fff;
-$navbar-inverse-brand-hover-bg:             transparent;
+$navbar-inverse-brand-color:                $navbar-inverse-link-color !default;
+$navbar-inverse-brand-hover-color:          #fff !default;
+$navbar-inverse-brand-hover-bg:             transparent !default;
 
 // Inverted navbar toggle
-$navbar-inverse-toggle-hover-bg:            darken($navbar-inverse-bg, 10%);
-$navbar-inverse-toggle-icon-bar-bg:         #fff;
-$navbar-inverse-toggle-border-color:        darken($navbar-inverse-bg, 10%);
+$navbar-inverse-toggle-hover-bg:            darken($navbar-inverse-bg, 10%) !default;
+$navbar-inverse-toggle-icon-bar-bg:         #fff !default;
+$navbar-inverse-toggle-border-color:        darken($navbar-inverse-bg, 10%) !default;
 
 
 //== Navs
@@ -414,97 +414,97 @@ $navbar-inverse-toggle-border-color:        darken($navbar-inverse-bg, 10%);
 //##
 
 //=== Shared nav styles
-$nav-link-padding:                          10px 15px;
-$nav-link-hover-bg:                         $gray-lighter;
+$nav-link-padding:                          10px 15px !default;
+$nav-link-hover-bg:                         $gray-lighter !default;
 
-$nav-disabled-link-color:                   $gray-light;
-$nav-disabled-link-hover-color:             $gray-light;
+$nav-disabled-link-color:                   $gray-light !default;
+$nav-disabled-link-hover-color:             $gray-light !default;
 
 //== Tabs
-$nav-tabs-border-color:                     #ddd;
+$nav-tabs-border-color:                     #ddd !default;
 
-$nav-tabs-link-hover-border-color:          $gray-lighter;
+$nav-tabs-link-hover-border-color:          $gray-lighter !default;
 
-$nav-tabs-active-link-hover-bg:             $body-bg;
-$nav-tabs-active-link-hover-color:          $gray;
-$nav-tabs-active-link-hover-border-color:   #ddd;
+$nav-tabs-active-link-hover-bg:             $body-bg !default;
+$nav-tabs-active-link-hover-color:          $gray !default;
+$nav-tabs-active-link-hover-border-color:   #ddd !default;
 
-$nav-tabs-justified-link-border-color:            #ddd;
-$nav-tabs-justified-active-link-border-color:     $body-bg;
+$nav-tabs-justified-link-border-color:            #ddd !default;
+$nav-tabs-justified-active-link-border-color:     $body-bg !default;
 
 //== Pills
-$nav-pills-border-radius:                   $border-radius-base;
-$nav-pills-active-link-hover-bg:            $component-active-bg;
-$nav-pills-active-link-hover-color:         $component-active-color;
+$nav-pills-border-radius:                   $border-radius-base !default;
+$nav-pills-active-link-hover-bg:            $component-active-bg !default;
+$nav-pills-active-link-hover-color:         $component-active-color !default;
 
 
 //== Pagination
 //
 //##
 
-$pagination-color:                     $headings-color;
-$pagination-bg:                        #fff;
-$pagination-border:                    #ddd;
+$pagination-color:                     $headings-color !default;
+$pagination-bg:                        #fff !default;
+$pagination-border:                    #ddd !default;
 
-$pagination-hover-color:               #fff;
-$pagination-hover-bg:                  $brand-primary;
-$pagination-hover-border:              $brand-primary;
+$pagination-hover-color:               #fff !default;
+$pagination-hover-bg:                  $brand-primary !default;
+$pagination-hover-border:              $brand-primary !default;
 
-$pagination-active-color:              #fff;
-$pagination-active-bg:                 $brand-primary;
-$pagination-active-border:             $brand-primary;
+$pagination-active-color:              #fff !default;
+$pagination-active-bg:                 $brand-primary !default;
+$pagination-active-border:             $brand-primary !default;
 
-$pagination-disabled-color:            $gray-lighter;
-$pagination-disabled-bg:               #fff;
-$pagination-disabled-border:           #ddd;
+$pagination-disabled-color:            $gray-lighter !default;
+$pagination-disabled-bg:               #fff !default;
+$pagination-disabled-border:           #ddd !default;
 
 
 //== Pager
 //
 //##
 
-$pager-bg:                             $pagination-bg;
-$pager-border:                         $pagination-border;
-$pager-border-radius:                  15px;
+$pager-bg:                             $pagination-bg !default;
+$pager-border:                         $pagination-border !default;
+$pager-border-radius:                  15px !default;
 
-$pager-hover-bg:                       $brand-primary;
+$pager-hover-bg:                       $brand-primary !default;
 
-$pager-active-bg:                      $brand-primary;
-$pager-active-color:                   #fff;
+$pager-active-bg:                      $brand-primary !default;
+$pager-active-color:                   #fff !default;
 
-$pager-disabled-color:                 $gray-lighter;
+$pager-disabled-color:                 $gray-lighter !default;
 
 
 //== Jumbotron
 //
 //##
 
-$jumbotron-padding:              30px;
-$jumbotron-color:                inherit;
-$jumbotron-bg:                   darken($body-bg, 3%);
-$jumbotron-heading-color:        inherit;
-$jumbotron-font-size:            ceil(($font-size-base * 1.5));
+$jumbotron-padding:              30px !default;
+$jumbotron-color:                inherit !default;
+$jumbotron-bg:                   darken($body-bg, 3%) !default;
+$jumbotron-heading-color:        inherit !default;
+$jumbotron-font-size:            ceil(($font-size-base * 1.5)) !default;
 
 
 //== Form states and alerts
 //
 //## Define colors for form feedback states and, by default, alerts.
 
-$state-success-text:             #468847;
-$state-success-bg:               #dff0d8;
-$state-success-border:           darken(adjust-hue($state-success-bg, -10), 5%);
+$state-success-text:             #468847 !default;
+$state-success-bg:               #dff0d8 !default;
+$state-success-border:           darken(adjust-hue($state-success-bg, -10), 5%) !default;
 
-$state-info-text:                #3a87ad;
-$state-info-bg:                  #d9edf7;
-$state-info-border:              darken(adjust-hue($state-info-bg, -10), 7%);
+$state-info-text:                #3a87ad !default;
+$state-info-bg:                  #d9edf7 !default;
+$state-info-border:              darken(adjust-hue($state-info-bg, -10), 7%) !default;
 
-$state-warning-text:             #c09853;
-$state-warning-bg:               #fcf8e3;
-$state-warning-border:           darken(adjust-hue($state-warning-bg, -10), 3%);
+$state-warning-text:             #c09853 !default;
+$state-warning-bg:               #fcf8e3 !default;
+$state-warning-border:           darken(adjust-hue($state-warning-bg, -10), 3%) !default;
 
-$state-danger-text:              #b94a48;
-$state-danger-bg:                #f2dede;
-$state-danger-border:            darken(adjust-hue($state-danger-bg, -10), 3%);
+$state-danger-text:              #b94a48 !default;
+$state-danger-bg:                #f2dede !default;
+$state-danger-border:            darken(adjust-hue($state-danger-bg, -10), 3%) !default;
 
 
 //== Tooltips
@@ -512,17 +512,17 @@ $state-danger-border:            darken(adjust-hue($state-danger-bg, -10), 3%);
 //##
 
 //** Tooltip max width
-$tooltip-max-width:           200px;
+$tooltip-max-width:           200px !default;
 //** Tooltip text color
-$tooltip-color:               #fff;
+$tooltip-color:               #fff !default;
 //** Tooltip background color
-$tooltip-bg:                  #000;
-$tooltip-opacity:             .9;
+$tooltip-bg:                  #000 !default;
+$tooltip-opacity:             .9 !default;
 
 //** Tooltip arrow width
-$tooltip-arrow-width:         5px;
+$tooltip-arrow-width:         5px !default;
 //** Tooltip arrow color
-$tooltip-arrow-color:         $tooltip-bg;
+$tooltip-arrow-color:         $tooltip-bg !default;
 
 
 //== Popovers
@@ -530,28 +530,28 @@ $tooltip-arrow-color:         $tooltip-bg;
 //##
 
 //** Popover body background color
-$popover-bg:                          #fff;
+$popover-bg:                          #fff !default;
 //** Popover maximum width
-$popover-max-width:                   276px;
+$popover-max-width:                   276px !default;
 //** Popover border color
-$popover-border-color:                rgba(0,0,0,.2);
+$popover-border-color:                rgba(0,0,0,.2) !default;
 //** Popover fallback border color
-$popover-fallback-border-color:       #ccc;
+$popover-fallback-border-color:       #ccc !default;
 
 //** Popover title background color
-$popover-title-bg:                    darken($popover-bg, 3%);
+$popover-title-bg:                    darken($popover-bg, 3%) !default;
 
 //** Popover arrow width
-$popover-arrow-width:                 10px;
+$popover-arrow-width:                 10px !default;
 //** Popover arrow color
-$popover-arrow-color:                 $popover-bg;
+$popover-arrow-color:                 $popover-bg !default;
 
 //** Popover outer arrow width
-$popover-arrow-outer-width:           ($popover-arrow-width + 1);
+$popover-arrow-outer-width:           ($popover-arrow-width + 1) !default;
 //** Popover outer arrow color
-$popover-arrow-outer-color:           fadein($popover-border-color, 5%);
+$popover-arrow-outer-color:           fadein($popover-border-color, 5%) !default;
 //** Popover outer arrow fallback color
-$popover-arrow-outer-fallback-color:  darken($popover-fallback-border-color, 20%);
+$popover-arrow-outer-fallback-color:  darken($popover-fallback-border-color, 20%) !default;
 
 
 //== Labels
@@ -559,22 +559,22 @@ $popover-arrow-outer-fallback-color:  darken($popover-fallback-border-color, 20%
 //##
 
 //** Default label background color
-$label-default-bg:            $btn-default-bg;
+$label-default-bg:            $btn-default-bg !default;
 //** Primary label background color
-$label-primary-bg:            $brand-primary;
+$label-primary-bg:            $brand-primary !default;
 //** Success label background color
-$label-success-bg:            $brand-success;
+$label-success-bg:            $brand-success !default;
 //** Info label background color
-$label-info-bg:               $brand-info;
+$label-info-bg:               $brand-info !default;
 //** Warning label background color
-$label-warning-bg:            $brand-warning;
+$label-warning-bg:            $brand-warning !default;
 //** Danger label background color
-$label-danger-bg:             $brand-danger;
+$label-danger-bg:             $brand-danger !default;
 
 //** Default label text color
-$label-color:                 #fff;
+$label-color:                 #fff !default;
 //** Default text color of a linked label
-$label-link-hover-color:      #fff;
+$label-link-hover-color:      #fff !default;
 
 
 //== Modals
@@ -582,57 +582,57 @@ $label-link-hover-color:      #fff;
 //##
 
 //** Padding applied to the modal body
-$modal-inner-padding:         20px;
+$modal-inner-padding:         20px !default;
 
 //** Padding applied to the modal title
-$modal-title-padding:         15px;
+$modal-title-padding:         15px !default;
 //** Modal title line-height
-$modal-title-line-height:     $line-height-base;
+$modal-title-line-height:     $line-height-base !default;
 
 //** Background color of modal content area
-$modal-content-bg:                             #fff;
+$modal-content-bg:                             #fff !default;
 //** Modal content border color
-$modal-content-border-color:                   rgba(0,0,0,.2);
+$modal-content-border-color:                   rgba(0,0,0,.2) !default;
 //** Modal content border color **for IE8**
-$modal-content-fallback-border-color:          #999;
+$modal-content-fallback-border-color:          #999 !default;
 
 //** Modal backdrop background color
-$modal-backdrop-bg:           #000;
+$modal-backdrop-bg:           #000 !default;
 //** Modal backdrop opacity
-$modal-backdrop-opacity:      .5;
+$modal-backdrop-opacity:      .5 !default;
 //** Modal header border color
-$modal-header-border-color:   #e5e5e5;
+$modal-header-border-color:   #e5e5e5 !default;
 //** Modal footer border color
-$modal-footer-border-color:   $modal-header-border-color;
+$modal-footer-border-color:   $modal-header-border-color !default;
 
-$modal-lg:                    900px;
-$modal-md:                    600px;
-$modal-sm:                    300px;
+$modal-lg:                    900px !default;
+$modal-md:                    600px !default;
+$modal-sm:                    300px !default;
 
 
 //== Alerts
 //
 //## Define alert colors, border radius, and padding.
 
-$alert-padding:               15px;
-$alert-border-radius:         $border-radius-base;
-$alert-link-font-weight:      bold;
+$alert-padding:               15px !default;
+$alert-border-radius:         $border-radius-base !default;
+$alert-link-font-weight:      bold !default;
 
-$alert-success-bg:            $state-success-bg;
-$alert-success-text:          $state-success-text;
-$alert-success-border:        $state-success-border;
+$alert-success-bg:            $state-success-bg !default;
+$alert-success-text:          $state-success-text !default;
+$alert-success-border:        $state-success-border !default;
 
-$alert-info-bg:               $state-info-bg;
-$alert-info-text:             $state-info-text;
-$alert-info-border:           $state-info-border;
+$alert-info-bg:               $state-info-bg !default;
+$alert-info-text:             $state-info-text !default;
+$alert-info-border:           $state-info-border !default;
 
-$alert-warning-bg:            $state-warning-bg;
-$alert-warning-text:          $state-warning-text;
-$alert-warning-border:        $state-warning-border;
+$alert-warning-bg:            $state-warning-bg !default;
+$alert-warning-text:          $state-warning-text !default;
+$alert-warning-border:        $state-warning-border !default;
 
-$alert-danger-bg:             $state-danger-bg;
-$alert-danger-text:           $state-danger-text;
-$alert-danger-border:         $state-danger-border;
+$alert-danger-bg:             $state-danger-bg !default;
+$alert-danger-text:           $state-danger-text !default;
+$alert-danger-border:         $state-danger-border !default;
 
 
 //== Progress bars
@@ -640,22 +640,22 @@ $alert-danger-border:         $state-danger-border;
 //##
 
 //** Background color of the whole progress component
-$progress-bg:                 #f5f5f5;
+$progress-bg:                 #f5f5f5 !default;
 //** Progress bar text color
-$progress-bar-color:          #fff;
+$progress-bar-color:          #fff !default;
 //** Variable for setting rounded corners on progress bar.
-$progress-border-radius:      $border-radius-base;
+$progress-border-radius:      $border-radius-base !default;
 
 //** Default progress bar color
-$progress-bar-bg:             $brand-primary;
+$progress-bar-bg:             $brand-primary !default;
 //** Success progress bar color
-$progress-bar-success-bg:     $brand-success;
+$progress-bar-success-bg:     $brand-success !default;
 //** Warning progress bar color
-$progress-bar-warning-bg:     $brand-warning;
+$progress-bar-warning-bg:     $brand-warning !default;
 //** Danger progress bar color
-$progress-bar-danger-bg:      $brand-danger;
+$progress-bar-danger-bg:      $brand-danger !default;
 //** Info progress bar color
-$progress-bar-info-bg:        $brand-info;
+$progress-bar-info-bg:        $brand-info !default;
 
 
 //== List group
@@ -663,72 +663,72 @@ $progress-bar-info-bg:        $brand-info;
 //##
 
 //** Background color on `.list-group-item`
-$list-group-bg:                 #fff;
+$list-group-bg:                 #fff !default;
 //** `.list-group-item` border color
-$list-group-border:             #ddd;
+$list-group-border:             #ddd !default;
 //** List group border radius
-$list-group-border-radius:      $border-radius-base;
+$list-group-border-radius:      $border-radius-base !default;
 
 //** Background color of single list items on hover
-$list-group-hover-bg:           #f5f5f5;
+$list-group-hover-bg:           #f5f5f5 !default;
 //** Text color of active list items
-$list-group-active-color:       $component-active-color;
+$list-group-active-color:       $component-active-color !default;
 //** Background color of active list items
-$list-group-active-bg:          $component-active-bg;
+$list-group-active-bg:          $component-active-bg !default;
 //** Border color of active list elements
-$list-group-active-border:      $list-group-active-bg;
+$list-group-active-border:      $list-group-active-bg !default;
 //** Text color for content within active list items
-$list-group-active-text-color:  lighten($list-group-active-bg, 40%);
+$list-group-active-text-color:  lighten($list-group-active-bg, 40%) !default;
 
 //** Text color of disabled list items
-$list-group-disabled-color:      $gray-light;
+$list-group-disabled-color:      $gray-light !default;
 //** Background color of disabled list items
-$list-group-disabled-bg:         $gray-lighter;
+$list-group-disabled-bg:         $gray-lighter !default;
 //** Text color for content within disabled list items
-$list-group-disabled-text-color: $list-group-disabled-color;
+$list-group-disabled-text-color: $list-group-disabled-color !default;
 
-$list-group-link-color:         #555;
-$list-group-link-hover-color:   $list-group-link-color;
-$list-group-link-heading-color: #333;
+$list-group-link-color:         #555 !default;
+$list-group-link-hover-color:   $list-group-link-color !default;
+$list-group-link-heading-color: #333 !default;
 
 
 //== Panels
 //
 //##
 
-$panel-bg:                    #fff;
-$panel-body-padding:          15px;
-$panel-heading-padding:       10px 15px;
-$panel-footer-padding:        $panel-heading-padding;
-$panel-border-radius:         $border-radius-base;
+$panel-bg:                    #fff !default;
+$panel-body-padding:          15px !default;
+$panel-heading-padding:       10px 15px !default;
+$panel-footer-padding:        $panel-heading-padding !default;
+$panel-border-radius:         $border-radius-base !default;
 
 //** Border color for elements within panels
-$panel-inner-border:          #ddd;
-$panel-footer-bg:             $body-bg;
+$panel-inner-border:          #ddd !default;
+$panel-footer-bg:             $body-bg !default;
 
-$panel-default-text:          $gray-dark;
-$panel-default-border:        #ddd;
-$panel-default-heading-bg:    $panel-footer-bg;
+$panel-default-text:          $gray-dark !default;
+$panel-default-border:        #ddd !default;
+$panel-default-heading-bg:    $panel-footer-bg !default;
 
-$panel-primary-text:          #fff;
-$panel-primary-border:        $brand-primary;
-$panel-primary-heading-bg:    $brand-primary;
+$panel-primary-text:          #fff !default;
+$panel-primary-border:        $brand-primary !default;
+$panel-primary-heading-bg:    $brand-primary !default;
 
-$panel-success-text:          #fff;
-$panel-success-border:        $brand-success;
-$panel-success-heading-bg:    $brand-success;
+$panel-success-text:          #fff !default;
+$panel-success-border:        $brand-success !default;
+$panel-success-heading-bg:    $brand-success !default;
 
-$panel-info-text:             #fff;
-$panel-info-border:           $brand-info;
-$panel-info-heading-bg:       $brand-info;
+$panel-info-text:             #fff !default;
+$panel-info-border:           $brand-info !default;
+$panel-info-heading-bg:       $brand-info !default;
 
-$panel-warning-text:          #fff;
-$panel-warning-border:        $brand-warning;
-$panel-warning-heading-bg:    $brand-warning;
+$panel-warning-text:          #fff !default;
+$panel-warning-border:        $brand-warning !default;
+$panel-warning-heading-bg:    $brand-warning !default;
 
-$panel-danger-text:           #fff;
-$panel-danger-border:         $brand-danger;
-$panel-danger-heading-bg:     $brand-danger;
+$panel-danger-text:           #fff !default;
+$panel-danger-border:         $brand-danger !default;
+$panel-danger-heading-bg:     $brand-danger !default;
 
 
 //== Thumbnails
@@ -736,103 +736,103 @@ $panel-danger-heading-bg:     $brand-danger;
 //##
 
 //** Padding around the thumbnail image
-$thumbnail-padding:           4px;
+$thumbnail-padding:           4px !default;
 //** Thumbnail background color
-$thumbnail-bg:                $body-bg;
+$thumbnail-bg:                $body-bg !default;
 //** Thumbnail border color
-$thumbnail-border:            #ddd;
+$thumbnail-border:            #ddd !default;
 //** Thumbnail border radius
-$thumbnail-border-radius:     $border-radius-base;
+$thumbnail-border-radius:     $border-radius-base !default;
 
 //** Custom text color for thumbnail captions
-$thumbnail-caption-color:     $text-color;
+$thumbnail-caption-color:     $text-color !default;
 //** Padding around the thumbnail caption
-$thumbnail-caption-padding:   9px;
+$thumbnail-caption-padding:   9px !default;
 
 
 //== Wells
 //
 //##
 
-$well-bg:                     darken($body-bg, 3%);
-$well-border:                 darken($well-bg, 7%);
+$well-bg:                     darken($body-bg, 3%) !default;
+$well-border:                 darken($well-bg, 7%) !default;
 
 
 //== Badges
 //
 //##
 
-$badge-color:                 #fff;
+$badge-color:                 #fff !default;
 //** Linked badge text color on hover
-$badge-link-hover-color:      #fff;
-$badge-bg:                    $link-color;
+$badge-link-hover-color:      #fff !default;
+$badge-bg:                    $link-color !default;
 
 //** Badge text color in active nav link
-$badge-active-color:          $link-color;
+$badge-active-color:          $link-color !default;
 //** Badge background color in active nav link
-$badge-active-bg:             #fff;
+$badge-active-bg:             #fff !default;
 
-$badge-font-weight:           bold;
-$badge-line-height:           1;
-$badge-border-radius:         10px;
+$badge-font-weight:           bold !default;
+$badge-line-height:           1 !default;
+$badge-border-radius:         10px !default;
 
 
 //== Breadcrumbs
 //
 //##
 
-$breadcrumb-padding-vertical:   8px;
-$breadcrumb-padding-horizontal: 15px;
+$breadcrumb-padding-vertical:   8px !default;
+$breadcrumb-padding-horizontal: 15px !default;
 //** Breadcrumb background color
-$breadcrumb-bg:                 transparent;
+$breadcrumb-bg:                 transparent !default;
 //** Breadcrumb text color
-$breadcrumb-color:              #ccc;
+$breadcrumb-color:              #ccc !default;
 //** Text color of current page in the breadcrumb
-$breadcrumb-active-color:       $gray-light;
+$breadcrumb-active-color:       $gray-light !default;
 //** Textual separator for between breadcrumb elements
-$breadcrumb-separator:          "/";
+$breadcrumb-separator:          "/" !default;
 
 
 //== Carousel
 //
 //##
 
-$carousel-text-shadow:                        0 1px 2px rgba(0,0,0,.6);
+$carousel-text-shadow:                        0 1px 2px rgba(0,0,0,.6) !default;
 
-$carousel-control-color:                      #fff;
-$carousel-control-width:                      15%;
-$carousel-control-opacity:                    .5;
-$carousel-control-font-size:                  20px;
+$carousel-control-color:                      #fff !default;
+$carousel-control-width:                      15% !default;
+$carousel-control-opacity:                    .5 !default;
+$carousel-control-font-size:                  20px !default;
 
-$carousel-indicator-active-bg:                #fff;
-$carousel-indicator-border-color:             #fff;
+$carousel-indicator-active-bg:                #fff !default;
+$carousel-indicator-border-color:             #fff !default;
 
-$carousel-caption-color:                      #fff;
+$carousel-caption-color:                      #fff !default;
 
 
 //== Close
 //
 //##
 
-$close-font-weight:           bold;
-$close-color:                 #000;
-$close-text-shadow:           0 1px 0 #fff;
+$close-font-weight:           bold !default;
+$close-color:                 #000 !default;
+$close-text-shadow:           0 1px 0 #fff !default;
 
 
 //== Code
 //
 //##
 
-$code-color:                  #c7254e;
-$code-bg:                     #f9f2f4;
+$code-color:                  #c7254e !default;
+$code-bg:                     #f9f2f4 !default;
 
-$kbd-color:                   #fff;
-$kbd-bg:                      #333;
+$kbd-color:                   #fff !default;
+$kbd-bg:                      #333 !default;
 
-$pre-bg:                      #f5f5f5;
-$pre-color:                   $gray-dark;
-$pre-border-color:            #ccc;
-$pre-scrollable-max-height:   340px;
+$pre-bg:                      #f5f5f5 !default;
+$pre-color:                   $gray-dark !default;
+$pre-border-color:            #ccc !default;
+$pre-scrollable-max-height:   340px !default;
 
 
 //== Type
@@ -840,22 +840,22 @@ $pre-scrollable-max-height:   340px;
 //##
 
 //** Horizontal offset for forms and lists.
-$component-offset-horizontal: 180px;
+$component-offset-horizontal: 180px !default;
 //** Text muted color
-$text-muted:                  $gray-light;
+$text-muted:                  $gray-light !default;
 //** Abbreviations and acronyms border color
-$abbr-border-color:           $gray-light;
+$abbr-border-color:           $gray-light !default;
 //** Headings small color
-$headings-small-color:        $gray-light;
+$headings-small-color:        $gray-light !default;
 //** Blockquote small color
-$blockquote-small-color:      $gray-light;
+$blockquote-small-color:      $gray-light !default;
 //** Blockquote font size
-$blockquote-font-size:        ($font-size-base * 1.25);
+$blockquote-font-size:        ($font-size-base * 1.25) !default;
 //** Blockquote border color
-$blockquote-border-color:     $gray-lighter;
+$blockquote-border-color:     $gray-lighter !default;
 //** Page header border color
-$page-header-border-color:    $gray-lighter;
+$page-header-border-color:    $gray-lighter !default;
 //** Width of horizontal description list titles
-$dl-horizontal-offset:        $component-offset-horizontal;
+$dl-horizontal-offset:        $component-offset-horizontal !default;
 //** Horizontal line color.
-$hr-border:                   $gray-lighter;
+$hr-border:                   $gray-lighter !default;
diff --git a/slate/_variables.scss b/slate/_variables.scss
index fbcd2e46..022878a0 100644
--- a/slate/_variables.scss
+++ b/slate/_variables.scss
@@ -7,18 +7,18 @@
 //
 //## Gray and brand colors for use across Bootstrap.
 
-$gray-base:              #000;
-$gray-darker:            #272B30; // #222
-$gray-dark:              #3A3F44;   // #333
-$gray:                   #52575C; // #555
-$gray-light:             #7A8288;   // #999
-$gray-lighter:           #999; // #eee
+$gray-base:              #000 !default;
+$gray-darker:            #272B30 !default; // #222
+$gray-dark:              #3A3F44 !default;   // #333
+$gray:                   #52575C !default; // #555
+$gray-light:             #7A8288 !default;   // #999
+$gray-lighter:           #999 !default; // #eee
 
-$brand-primary:         $gray-light;
-$brand-success:         #62c462;
-$brand-info:            #5bc0de;
-$brand-warning:         #f89406;
-$brand-danger:          #ee5f5b;
+$brand-primary:         $gray-light !default;
+$brand-success:         #62c462 !default;
+$brand-info:            #5bc0de !default;
+$brand-warning:         #f89406 !default;
+$brand-danger:          #ee5f5b !default;
 
 
 //== Scaffolding
@@ -26,49 +26,49 @@ $brand-danger:          #ee5f5b;
 //## Settings for some of the most global styles.
 
 //** Background color for ``.
-$body-bg:               $gray-darker;
+$body-bg:               $gray-darker !default;
 //** Global text color on ``.
-$text-color:            #C8C8C8;
+$text-color:            #C8C8C8 !default;
 
 //** Global textual link color.
-$link-color:            #fff;
+$link-color:            #fff !default;
 //** Link hover color set via `darken()` function.
-$link-hover-color:      #fff;
+$link-hover-color:      #fff !default;
 //** Link hover decoration.
-$link-hover-decoration: underline;
+$link-hover-decoration: underline !default;
 
 
 //== Typography
 //
 //## Font, line-height, and color for body text, headings, and more.
 
-$font-family-sans-serif:  "Helvetica Neue", Helvetica, Arial, sans-serif;
-$font-family-serif:       Georgia, "Times New Roman", Times, serif;
+$font-family-sans-serif:  "Helvetica Neue", Helvetica, Arial, sans-serif !default;
+$font-family-serif:       Georgia, "Times New Roman", Times, serif !default;
 //** Default monospace fonts for ``, ``, and `
`.
-$font-family-monospace:   Menlo, Monaco, Consolas, "Courier New", monospace;
-$font-family-base:        $font-family-sans-serif;
+$font-family-monospace:   Menlo, Monaco, Consolas, "Courier New", monospace !default;
+$font-family-base:        $font-family-sans-serif !default;
 
-$font-size-base:          14px;
-$font-size-large:         ceil(($font-size-base * 1.25)); // ~18px
-$font-size-small:         ceil(($font-size-base * 0.85)); // ~12px
+$font-size-base:          14px !default;
+$font-size-large:         ceil(($font-size-base * 1.25)) !default; // ~18px
+$font-size-small:         ceil(($font-size-base * 0.85)) !default; // ~12px
 
-$font-size-h1:            floor(($font-size-base * 2.6)); // ~36px
-$font-size-h2:            floor(($font-size-base * 2.15)); // ~30px
-$font-size-h3:            ceil(($font-size-base * 1.7)); // ~24px
-$font-size-h4:            ceil(($font-size-base * 1.25)); // ~18px
-$font-size-h5:            $font-size-base;
-$font-size-h6:            ceil(($font-size-base * 0.85)); // ~12px
+$font-size-h1:            floor(($font-size-base * 2.6)) !default; // ~36px
+$font-size-h2:            floor(($font-size-base * 2.15)) !default; // ~30px
+$font-size-h3:            ceil(($font-size-base * 1.7)) !default; // ~24px
+$font-size-h4:            ceil(($font-size-base * 1.25)) !default; // ~18px
+$font-size-h5:            $font-size-base !default;
+$font-size-h6:            ceil(($font-size-base * 0.85)) !default; // ~12px
 
 //** Unit-less `line-height` for use in components like buttons.
-$line-height-base:        1.428571429; // 20/14
+$line-height-base:        1.428571429 !default; // 20/14
 //** Computed "line-height" (`font-size` * `line-height`) for use with `margin`, `padding`, etc.
-$line-height-computed:    floor(($font-size-base * $line-height-base)); // ~20px
+$line-height-computed:    floor(($font-size-base * $line-height-base)) !default; // ~20px
 
 //** By default, this inherits from the ``.
-$headings-font-family:    $font-family-base;
-$headings-font-weight:    500;
-$headings-line-height:    1.1;
-$headings-color:          inherit;
+$headings-font-family:    $font-family-base !default;
+$headings-font-weight:    500 !default;
+$headings-line-height:    1.1 !default;
+$headings-color:          inherit !default;
 
 
 //== Iconography
@@ -76,45 +76,45 @@ $headings-color:          inherit;
 //## Specify custom location and filename of the included Glyphicons icon font. Useful for those including Bootstrap via Bower.
 
 //** Load fonts from this directory.
-$icon-font-path:          "../fonts/";
+$icon-font-path:          "../fonts/" !default;
 //** File name for all font files.
-$icon-font-name:          "glyphicons-halflings-regular";
+$icon-font-name:          "glyphicons-halflings-regular" !default;
 //** Element ID within SVG icon file.
-$icon-font-svg-id:        "glyphicons_halflingsregular";
+$icon-font-svg-id:        "glyphicons_halflingsregular" !default;
 
 
 //== Components
 //
 //## Define common padding and border radius sizes and more. Values based on 14px text and 1.428 line-height (~20px to start).
 
-$padding-base-vertical:     8px;
-$padding-base-horizontal:   12px;
+$padding-base-vertical:     8px !default;
+$padding-base-horizontal:   12px !default;
 
-$padding-large-vertical:    14px;
-$padding-large-horizontal:  16px;
+$padding-large-vertical:    14px !default;
+$padding-large-horizontal:  16px !default;
 
-$padding-small-vertical:    5px;
-$padding-small-horizontal:  10px;
+$padding-small-vertical:    5px !default;
+$padding-small-horizontal:  10px !default;
 
-$padding-xs-vertical:       1px;
-$padding-xs-horizontal:     5px;
+$padding-xs-vertical:       1px !default;
+$padding-xs-horizontal:     5px !default;
 
-$line-height-large:         1.3333333; // extra decimals for Win 8.1 Chrome
-$line-height-small:         1.5;
+$line-height-large:         1.3333333 !default; // extra decimals for Win 8.1 Chrome
+$line-height-small:         1.5 !default;
 
-$border-radius-base:        4px;
-$border-radius-large:       6px;
-$border-radius-small:       3px;
+$border-radius-base:        4px !default;
+$border-radius-large:       6px !default;
+$border-radius-small:       3px !default;
 
 //** Global color for active items (e.g., navs or dropdowns).
-$component-active-color:    #fff;
+$component-active-color:    #fff !default;
 //** Global background color for active items (e.g., navs or dropdowns).
-$component-active-bg:       transparent;
+$component-active-bg:       transparent !default;
 
 //** Width of the `border` for generating carets that indicator dropdowns.
-$caret-width-base:          4px;
+$caret-width-base:          4px !default;
 //** Carets increase slightly in size for larger components.
-$caret-width-large:         5px;
+$caret-width-large:         5px !default;
 
 
 //== Tables
@@ -122,53 +122,53 @@ $caret-width-large:         5px;
 //## Customizes the `.table` component with basic values, each used across all table variations.
 
 //** Padding for ``s and ``s.
-$table-cell-padding:            8px;
+$table-cell-padding:            8px !default;
 //** Padding for cells in `.table-condensed`.
-$table-condensed-cell-padding:  5px;
+$table-condensed-cell-padding:  5px !default;
 
 //** Default background color used for all tables.
-$table-bg:                      lighten($body-bg, 3%);
+$table-bg:                      lighten($body-bg, 3%) !default;
 //** Background color used for `.table-striped`.
-$table-bg-accent:               lighten($table-bg, 3%);
+$table-bg-accent:               lighten($table-bg, 3%) !default;
 //** Background color used for `.table-hover`.
-$table-bg-hover:                lighten($table-bg, 12%);
-$table-bg-active:               $table-bg-hover;
+$table-bg-hover:                lighten($table-bg, 12%) !default;
+$table-bg-active:               $table-bg-hover !default;
 
 //** Border color for table and cell borders.
-$table-border-color:            darken($gray-darker, 5%);
+$table-border-color:            darken($gray-darker, 5%) !default;
 
 
 //== Buttons
 //
 //## For each of Bootstrap's buttons, define text, background and border color.
 
-$btn-font-weight:                normal;
+$btn-font-weight:                normal !default;
 
-$btn-default-color:              #fff;
-$btn-default-bg:                 $gray-dark;
-$btn-default-border:             $btn-default-bg;
+$btn-default-color:              #fff !default;
+$btn-default-bg:                 $gray-dark !default;
+$btn-default-border:             $btn-default-bg !default;
 
-$btn-primary-color:              $btn-default-color;
-$btn-primary-bg:                 $brand-primary;
-$btn-primary-border:             $btn-primary-bg;
+$btn-primary-color:              $btn-default-color !default;
+$btn-primary-bg:                 $brand-primary !default;
+$btn-primary-border:             $btn-primary-bg !default;
 
-$btn-success-color:              $btn-default-color;
-$btn-success-bg:                 $brand-success;
-$btn-success-border:             $btn-success-bg;
+$btn-success-color:              $btn-default-color !default;
+$btn-success-bg:                 $brand-success !default;
+$btn-success-border:             $btn-success-bg !default;
 
-$btn-info-color:                 $btn-default-color;
-$btn-info-bg:                    $brand-info;
-$btn-info-border:                $btn-info-bg;
+$btn-info-color:                 $btn-default-color !default;
+$btn-info-bg:                    $brand-info !default;
+$btn-info-border:                $btn-info-bg !default;
 
-$btn-warning-color:              $btn-default-color;
-$btn-warning-bg:                 $brand-warning;
-$btn-warning-border:             $btn-warning-bg;
+$btn-warning-color:              $btn-default-color !default;
+$btn-warning-bg:                 $brand-warning !default;
+$btn-warning-border:             $btn-warning-bg !default;
 
-$btn-danger-color:               $btn-default-color;
-$btn-danger-bg:                  $brand-danger;
-$btn-danger-border:              $btn-danger-bg;
+$btn-danger-color:               $btn-default-color !default;
+$btn-danger-bg:                  $brand-danger !default;
+$btn-danger-border:              $btn-danger-bg !default;
 
-$btn-link-disabled-color:        $gray-light;
+$btn-link-disabled-color:        $gray-light !default;
 
 
 //== Forms
@@ -176,50 +176,50 @@ $btn-link-disabled-color:        $gray-light;
 //##
 
 //** `` background color
-$input-bg:                       #fff;
+$input-bg:                       #fff !default;
 //** `` background color
-$input-bg-disabled:              $gray-lighter;
+$input-bg-disabled:              $gray-lighter !default;
 
 //** Text color for ``s
-$input-color:                    $gray-darker;
+$input-color:                    $gray-darker !default;
 //** `` border color
-$input-border:                   #ccc;
+$input-border:                   #ccc !default;
 
 // TODO: Rename `$input-border-radius` to `$input-border-radius-base` in v4
 //** Default `.form-control` border radius
 // This has no effect on ``s in CSS.
-$input-border-radius:            $border-radius-base;
+$input-border-radius:            $border-radius-base !default;
 //** Large `.form-control` border radius
-$input-border-radius-large:      $border-radius-large;
+$input-border-radius-large:      $border-radius-large !default;
 //** Small `.form-control` border radius
-$input-border-radius-small:      $border-radius-small;
+$input-border-radius-small:      $border-radius-small !default;
 
 //** Border color for inputs on focus
-$input-border-focus:             #66afe9;
+$input-border-focus:             #66afe9 !default;
 
 //** Placeholder text color
-$input-color-placeholder:        $gray-light;
+$input-color-placeholder:        $gray-light !default;
 
 //** Default `.form-control` height
-$input-height-base:              ($line-height-computed + ($padding-base-vertical * 2) + 2);
+$input-height-base:              ($line-height-computed + ($padding-base-vertical * 2) + 2) !default;
 //** Large `.form-control` height
-$input-height-large:             (ceil($font-size-large * $line-height-large) + ($padding-large-vertical * 2) + 2);
+$input-height-large:             (ceil($font-size-large * $line-height-large) + ($padding-large-vertical * 2) + 2) !default;
 //** Small `.form-control` height
-$input-height-small:             (floor($font-size-small * $line-height-small) + ($padding-small-vertical * 2) + 2);
+$input-height-small:             (floor($font-size-small * $line-height-small) + ($padding-small-vertical * 2) + 2) !default;
 
 //** `.form-group` margin
-$form-group-margin-bottom:       15px;
+$form-group-margin-bottom:       15px !default;
 
-$legend-color:                   $text-color;
-$legend-border-color:            darken($gray-darker, 5%);
+$legend-color:                   $text-color !default;
+$legend-border-color:            darken($gray-darker, 5%) !default;
 
 //** Background color for textual input addons
-$input-group-addon-bg:           $gray-lighter;
+$input-group-addon-bg:           $gray-lighter !default;
 //** Border color for textual input addons
-$input-group-addon-border-color: $input-border;
+$input-group-addon-border-color: $input-border !default;
 
 //** Disabled cursor for form controls and buttons.
-$cursor-disabled:                not-allowed;
+$cursor-disabled:                not-allowed !default;
 
 
 //== Dropdowns
@@ -227,34 +227,34 @@ $cursor-disabled:                not-allowed;
 //## Dropdown menu container and contents.
 
 //** Background for the dropdown menu.
-$dropdown-bg:                    $gray-dark;
+$dropdown-bg:                    $gray-dark !default;
 //** Dropdown menu `border-color`.
-$dropdown-border:                rgba(0,0,0,.15);
+$dropdown-border:                rgba(0,0,0,.15) !default;
 //** Dropdown menu `border-color` **for IE8**.
-$dropdown-fallback-border:       $gray-darker;
+$dropdown-fallback-border:       $gray-darker !default;
 //** Divider color for between dropdown items.
-$dropdown-divider-bg:            $gray-darker;
+$dropdown-divider-bg:            $gray-darker !default;
 
 //** Dropdown link text color.
-$dropdown-link-color:            $text-color;
+$dropdown-link-color:            $text-color !default;
 //** Hover color for dropdown links.
-$dropdown-link-hover-color:      #fff;
+$dropdown-link-hover-color:      #fff !default;
 //** Hover background for dropdown links.
-$dropdown-link-hover-bg:         $gray-darker;
+$dropdown-link-hover-bg:         $gray-darker !default;
 
 //** Active dropdown menu item text color.
-$dropdown-link-active-color:     #fff;
+$dropdown-link-active-color:     #fff !default;
 //** Active dropdown menu item background color.
-$dropdown-link-active-bg:        $gray-darker;
+$dropdown-link-active-bg:        $gray-darker !default;
 
 //** Disabled dropdown menu item background color.
-$dropdown-link-disabled-color:   $gray-light;
+$dropdown-link-disabled-color:   $gray-light !default;
 
 //** Text color for headers within dropdown menus.
-$dropdown-header-color:          $gray-light;
+$dropdown-header-color:          $gray-light !default;
 
 //** Deprecated `$dropdown-caret-color` as of v3.1.0
-$dropdown-caret-color:           #000;
+$dropdown-caret-color:           #000 !default;
 
 
 //-- Z-index master list
@@ -264,13 +264,13 @@ $dropdown-caret-color:           #000;
 //
 // Note: These variables are not generated into the Customizer.
 
-$zindex-navbar:            1000;
-$zindex-dropdown:          1000;
-$zindex-popover:           1060;
-$zindex-tooltip:           1070;
-$zindex-navbar-fixed:      1030;
-$zindex-modal-background:  1040;
-$zindex-modal:             1050;
+$zindex-navbar:            1000 !default;
+$zindex-dropdown:          1000 !default;
+$zindex-popover:           1060 !default;
+$zindex-tooltip:           1070 !default;
+$zindex-navbar-fixed:      1030 !default;
+$zindex-modal-background:  1040 !default;
+$zindex-modal:             1050 !default;
 
 
 //== Media queries breakpoints
@@ -279,37 +279,37 @@ $zindex-modal:             1050;
 
 // Extra small screen / phone
 //** Deprecated `$screen-xs` as of v3.0.1
-$screen-xs:                  480px;
+$screen-xs:                  480px !default;
 //** Deprecated `$screen-xs-min` as of v3.2.0
-$screen-xs-min:              $screen-xs;
+$screen-xs-min:              $screen-xs !default;
 //** Deprecated `$screen-phone` as of v3.0.1
-$screen-phone:               $screen-xs-min;
+$screen-phone:               $screen-xs-min !default;
 
 // Small screen / tablet
 //** Deprecated `$screen-sm` as of v3.0.1
-$screen-sm:                  768px;
-$screen-sm-min:              $screen-sm;
+$screen-sm:                  768px !default;
+$screen-sm-min:              $screen-sm !default;
 //** Deprecated `$screen-tablet` as of v3.0.1
-$screen-tablet:              $screen-sm-min;
+$screen-tablet:              $screen-sm-min !default;
 
 // Medium screen / desktop
 //** Deprecated `$screen-md` as of v3.0.1
-$screen-md:                  992px;
-$screen-md-min:              $screen-md;
+$screen-md:                  992px !default;
+$screen-md-min:              $screen-md !default;
 //** Deprecated `$screen-desktop` as of v3.0.1
-$screen-desktop:             $screen-md-min;
+$screen-desktop:             $screen-md-min !default;
 
 // Large screen / wide desktop
 //** Deprecated `$screen-lg` as of v3.0.1
-$screen-lg:                  1200px;
-$screen-lg-min:              $screen-lg;
+$screen-lg:                  1200px !default;
+$screen-lg-min:              $screen-lg !default;
 //** Deprecated `$screen-lg-desktop` as of v3.0.1
-$screen-lg-desktop:          $screen-lg-min;
+$screen-lg-desktop:          $screen-lg-min !default;
 
 // So media queries don't overlap when required, provide a maximum
-$screen-xs-max:              ($screen-sm-min - 1);
-$screen-sm-max:              ($screen-md-min - 1);
-$screen-md-max:              ($screen-lg-min - 1);
+$screen-xs-max:              ($screen-sm-min - 1) !default;
+$screen-sm-max:              ($screen-md-min - 1) !default;
+$screen-md-max:              ($screen-lg-min - 1) !default;
 
 
 //== Grid system
@@ -317,14 +317,14 @@ $screen-md-max:              ($screen-lg-min - 1);
 //## Define your custom responsive grid.
 
 //** Number of columns in the grid.
-$grid-columns:              12;
+$grid-columns:              12 !default;
 //** Padding between columns. Gets divided in half for the left and right.
-$grid-gutter-width:         30px;
+$grid-gutter-width:         30px !default;
 // Navbar collapse
 //** Point at which the navbar becomes uncollapsed.
-$grid-float-breakpoint:     $screen-sm-min;
+$grid-float-breakpoint:     $screen-sm-min !default;
 //** Point at which the navbar begins collapsing.
-$grid-float-breakpoint-max: ($grid-float-breakpoint - 1);
+$grid-float-breakpoint-max: ($grid-float-breakpoint - 1) !default;
 
 
 //== Container sizes
@@ -332,19 +332,19 @@ $grid-float-breakpoint-max: ($grid-float-breakpoint - 1);
 //## Define the maximum width of `.container` for different screen sizes.
 
 // Small screen / tablet
-$container-tablet:             (720px + $grid-gutter-width);
+$container-tablet:             (720px + $grid-gutter-width) !default;
 //** For `$screen-sm-min` and up.
-$container-sm:                 $container-tablet;
+$container-sm:                 $container-tablet !default;
 
 // Medium screen / desktop
-$container-desktop:            (940px + $grid-gutter-width);
+$container-desktop:            (940px + $grid-gutter-width) !default;
 //** For `$screen-md-min` and up.
-$container-md:                 $container-desktop;
+$container-md:                 $container-desktop !default;
 
 // Large screen / wide desktop
-$container-large-desktop:      (1140px + $grid-gutter-width);
+$container-large-desktop:      (1140px + $grid-gutter-width) !default;
 //** For `$screen-lg-min` and up.
-$container-lg:                 $container-large-desktop;
+$container-lg:                 $container-large-desktop !default;
 
 
 //== Navbar
@@ -352,61 +352,61 @@ $container-lg:                 $container-large-desktop;
 //##
 
 // Basics of a navbar
-$navbar-height:                    50px;
-$navbar-margin-bottom:             $line-height-computed;
-$navbar-border-radius:             $border-radius-base;
-$navbar-padding-horizontal:        floor(($grid-gutter-width / 2));
-$navbar-padding-vertical:          (($navbar-height - $line-height-computed) / 2);
-$navbar-collapse-max-height:       340px;
+$navbar-height:                    50px !default;
+$navbar-margin-bottom:             $line-height-computed !default;
+$navbar-border-radius:             $border-radius-base !default;
+$navbar-padding-horizontal:        floor(($grid-gutter-width / 2)) !default;
+$navbar-padding-vertical:          (($navbar-height - $line-height-computed) / 2) !default;
+$navbar-collapse-max-height:       340px !default;
 
-$navbar-default-color:             $text-color;
-$navbar-default-bg:                $gray-dark;
-$navbar-default-border:            darken($navbar-default-bg, 6.5%);
+$navbar-default-color:             $text-color !default;
+$navbar-default-bg:                $gray-dark !default;
+$navbar-default-border:            darken($navbar-default-bg, 6.5%) !default;
 
 // Navbar links
-$navbar-default-link-color:                $text-color;
-$navbar-default-link-hover-color:          #fff;
-$navbar-default-link-hover-bg:             darken($navbar-default-bg, 8%);
-$navbar-default-link-active-color:         #fff;
-$navbar-default-link-active-bg:            darken($navbar-default-bg, 8%);
-$navbar-default-link-disabled-color:       #ccc;
-$navbar-default-link-disabled-bg:          transparent;
+$navbar-default-link-color:                $text-color !default;
+$navbar-default-link-hover-color:          #fff !default;
+$navbar-default-link-hover-bg:             darken($navbar-default-bg, 8%) !default;
+$navbar-default-link-active-color:         #fff !default;
+$navbar-default-link-active-bg:            darken($navbar-default-bg, 8%) !default;
+$navbar-default-link-disabled-color:       #ccc !default;
+$navbar-default-link-disabled-bg:          transparent !default;
 
 // Navbar brand label
-$navbar-default-brand-color:               $navbar-default-link-color;
-$navbar-default-brand-hover-color:         #fff;
-$navbar-default-brand-hover-bg:            none;
+$navbar-default-brand-color:               $navbar-default-link-color !default;
+$navbar-default-brand-hover-color:         #fff !default;
+$navbar-default-brand-hover-bg:            none !default;
 
 // Navbar toggle
-$navbar-default-toggle-hover-bg:           darken($navbar-default-bg, 8%);
-$navbar-default-toggle-icon-bar-bg:        $text-color;
-$navbar-default-toggle-border-color:       darken($navbar-default-bg, 8%);
+$navbar-default-toggle-hover-bg:           darken($navbar-default-bg, 8%) !default;
+$navbar-default-toggle-icon-bar-bg:        $text-color !default;
+$navbar-default-toggle-border-color:       darken($navbar-default-bg, 8%) !default;
 
 
 // Inverted navbar
 // Reset inverted navbar basics
-$navbar-inverse-color:                      #ccc;
-$navbar-inverse-bg:                         $brand-primary;
-$navbar-inverse-border:                     darken($navbar-inverse-bg, 10%);
+$navbar-inverse-color:                      #ccc !default;
+$navbar-inverse-bg:                         $brand-primary !default;
+$navbar-inverse-border:                     darken($navbar-inverse-bg, 10%) !default;
 
 // Inverted navbar links
-$navbar-inverse-link-color:                 #ccc;
-$navbar-inverse-link-hover-color:           #fff;
-$navbar-inverse-link-hover-bg:              darken($navbar-inverse-bg, 12%);
-$navbar-inverse-link-active-color:          $navbar-inverse-link-hover-color;
-$navbar-inverse-link-active-bg:             darken($navbar-inverse-bg, 12%);
-$navbar-inverse-link-disabled-color:        #ccc;
-$navbar-inverse-link-disabled-bg:           transparent;
+$navbar-inverse-link-color:                 #ccc !default;
+$navbar-inverse-link-hover-color:           #fff !default;
+$navbar-inverse-link-hover-bg:              darken($navbar-inverse-bg, 12%) !default;
+$navbar-inverse-link-active-color:          $navbar-inverse-link-hover-color !default;
+$navbar-inverse-link-active-bg:             darken($navbar-inverse-bg, 12%) !default;
+$navbar-inverse-link-disabled-color:        #ccc !default;
+$navbar-inverse-link-disabled-bg:           transparent !default;
 
 // Inverted navbar brand label
-$navbar-inverse-brand-color:                $navbar-inverse-link-color;
-$navbar-inverse-brand-hover-color:          #fff;
-$navbar-inverse-brand-hover-bg:             none;
+$navbar-inverse-brand-color:                $navbar-inverse-link-color !default;
+$navbar-inverse-brand-hover-color:          #fff !default;
+$navbar-inverse-brand-hover-bg:             none !default;
 
 // Inverted navbar toggle
-$navbar-inverse-toggle-hover-bg:            darken($navbar-inverse-bg, 12%);
-$navbar-inverse-toggle-icon-bar-bg:         #fff;
-$navbar-inverse-toggle-border-color:        darken($navbar-inverse-bg, 12%);
+$navbar-inverse-toggle-hover-bg:            darken($navbar-inverse-bg, 12%) !default;
+$navbar-inverse-toggle-icon-bar-bg:         #fff !default;
+$navbar-inverse-toggle-border-color:        darken($navbar-inverse-bg, 12%) !default;
 
 
 //== Navs
@@ -414,97 +414,97 @@ $navbar-inverse-toggle-border-color:        darken($navbar-inverse-bg, 12%);
 //##
 
 //=== Shared nav styles
-$nav-link-padding:                          10px 15px;
-$nav-link-hover-bg:                         lighten($body-bg, 10%);
+$nav-link-padding:                          10px 15px !default;
+$nav-link-hover-bg:                         lighten($body-bg, 10%) !default;
 
-$nav-disabled-link-color:                   $gray-light;
-$nav-disabled-link-hover-color:             $gray-light;
+$nav-disabled-link-color:                   $gray-light !default;
+$nav-disabled-link-hover-color:             $gray-light !default;
 
 //== Tabs
-$nav-tabs-border-color:                     darken($gray-darker, 5%);
+$nav-tabs-border-color:                     darken($gray-darker, 5%) !default;
 
-$nav-tabs-link-hover-border-color:          darken($gray-darker, 5%);
+$nav-tabs-link-hover-border-color:          darken($gray-darker, 5%) !default;
 
-$nav-tabs-active-link-hover-bg:             lighten($body-bg, 10%);
-$nav-tabs-active-link-hover-color:          #fff;
-$nav-tabs-active-link-hover-border-color:   darken($gray-darker, 5%);
+$nav-tabs-active-link-hover-bg:             lighten($body-bg, 10%) !default;
+$nav-tabs-active-link-hover-color:          #fff !default;
+$nav-tabs-active-link-hover-border-color:   darken($gray-darker, 5%) !default;
 
-$nav-tabs-justified-link-border-color:            $nav-tabs-border-color;
-$nav-tabs-justified-active-link-border-color:     $body-bg;
+$nav-tabs-justified-link-border-color:            $nav-tabs-border-color !default;
+$nav-tabs-justified-active-link-border-color:     $body-bg !default;
 
 //== Pills
-$nav-pills-border-radius:                   $border-radius-base;
-$nav-pills-active-link-hover-bg:            $component-active-bg;
-$nav-pills-active-link-hover-color:         $component-active-color;
+$nav-pills-border-radius:                   $border-radius-base !default;
+$nav-pills-active-link-hover-bg:            $component-active-bg !default;
+$nav-pills-active-link-hover-color:         $component-active-color !default;
 
 
 //== Pagination
 //
 //##
 
-$pagination-color:                     $link-color;
-$pagination-bg:                        $btn-default-bg;
-$pagination-border:                    rgba(0, 0, 0, 0.6);
+$pagination-color:                     $link-color !default;
+$pagination-bg:                        $btn-default-bg !default;
+$pagination-border:                    rgba(0, 0, 0, 0.6) !default;
 
-$pagination-hover-color:               $link-hover-color;
-$pagination-hover-bg:                  transparent;
-$pagination-hover-border:              rgba(0, 0, 0, 0.6);
+$pagination-hover-color:               $link-hover-color !default;
+$pagination-hover-bg:                  transparent !default;
+$pagination-hover-border:              rgba(0, 0, 0, 0.6) !default;
 
-$pagination-active-color:              #fff;
-$pagination-active-bg:                 darken($pagination-bg, 10%);
-$pagination-active-border:             rgba(0, 0, 0, 0.6);
+$pagination-active-color:              #fff !default;
+$pagination-active-bg:                 darken($pagination-bg, 10%) !default;
+$pagination-active-border:             rgba(0, 0, 0, 0.6) !default;
 
-$pagination-disabled-color:            $gray-light;
-$pagination-disabled-bg:               #fff;
-$pagination-disabled-border:           rgba(0, 0, 0, 0.6);
+$pagination-disabled-color:            $gray-light !default;
+$pagination-disabled-bg:               #fff !default;
+$pagination-disabled-border:           rgba(0, 0, 0, 0.6) !default;
 
 
 //== Pager
 //
 //##
 
-$pager-bg:                             $pagination-bg;
-$pager-border:                         $pagination-border;
-$pager-border-radius:                  15px;
+$pager-bg:                             $pagination-bg !default;
+$pager-border:                         $pagination-border !default;
+$pager-border-radius:                  15px !default;
 
-$pager-hover-bg:                       $pagination-hover-bg;
+$pager-hover-bg:                       $pagination-hover-bg !default;
 
-$pager-active-bg:                      $pagination-active-bg;
-$pager-active-color:                   $pagination-active-color;
+$pager-active-bg:                      $pagination-active-bg !default;
+$pager-active-color:                   $pagination-active-color !default;
 
-$pager-disabled-color:                 $gray-light;
+$pager-disabled-color:                 $gray-light !default;
 
 
 //== Jumbotron
 //
 //##
 
-$jumbotron-padding:              30px;
-$jumbotron-color:                inherit;
-$jumbotron-bg:                   darken($body-bg, 5%);
-$jumbotron-heading-color:        inherit;
-$jumbotron-font-size:            ceil(($font-size-base * 1.5));
+$jumbotron-padding:              30px !default;
+$jumbotron-color:                inherit !default;
+$jumbotron-bg:                   darken($body-bg, 5%) !default;
+$jumbotron-heading-color:        inherit !default;
+$jumbotron-font-size:            ceil(($font-size-base * 1.5)) !default;
 
 
 //== Form states and alerts
 //
 //## Define colors for form feedback states and, by default, alerts.
 
-$state-success-text:             #fff;
-$state-success-bg:               $brand-success;
-$state-success-border:           darken(adjust-hue($state-success-bg, -10), 5%);
+$state-success-text:             #fff !default;
+$state-success-bg:               $brand-success !default;
+$state-success-border:           darken(adjust-hue($state-success-bg, -10), 5%) !default;
 
-$state-info-text:                #fff;
-$state-info-bg:                  $brand-info;
-$state-info-border:              darken(adjust-hue($state-info-bg, -10), 7%);
+$state-info-text:                #fff !default;
+$state-info-bg:                  $brand-info !default;
+$state-info-border:              darken(adjust-hue($state-info-bg, -10), 7%) !default;
 
-$state-warning-text:             #fff;
-$state-warning-bg:               $brand-warning;
-$state-warning-border:           darken(adjust-hue($state-warning-bg, -10), 3%);
+$state-warning-text:             #fff !default;
+$state-warning-bg:               $brand-warning !default;
+$state-warning-border:           darken(adjust-hue($state-warning-bg, -10), 3%) !default;
 
-$state-danger-text:              #fff;
-$state-danger-bg:                $brand-danger;
-$state-danger-border:            darken(adjust-hue($state-danger-bg, -10), 3%);
+$state-danger-text:              #fff !default;
+$state-danger-bg:                $brand-danger !default;
+$state-danger-border:            darken(adjust-hue($state-danger-bg, -10), 3%) !default;
 
 
 //== Tooltips
@@ -512,17 +512,17 @@ $state-danger-border:            darken(adjust-hue($state-danger-bg, -10), 3%);
 //##
 
 //** Tooltip max width
-$tooltip-max-width:           200px;
+$tooltip-max-width:           200px !default;
 //** Tooltip text color
-$tooltip-color:               #fff;
+$tooltip-color:               #fff !default;
 //** Tooltip background color
-$tooltip-bg:                  #000;
-$tooltip-opacity:             .9;
+$tooltip-bg:                  #000 !default;
+$tooltip-opacity:             .9 !default;
 
 //** Tooltip arrow width
-$tooltip-arrow-width:         5px;
+$tooltip-arrow-width:         5px !default;
 //** Tooltip arrow color
-$tooltip-arrow-color:         $tooltip-bg;
+$tooltip-arrow-color:         $tooltip-bg !default;
 
 
 //== Popovers
@@ -530,28 +530,28 @@ $tooltip-arrow-color:         $tooltip-bg;
 //##
 
 //** Popover body background color
-$popover-bg:                          lighten($body-bg, 3%);
+$popover-bg:                          lighten($body-bg, 3%) !default;
 //** Popover maximum width
-$popover-max-width:                   276px;
+$popover-max-width:                   276px !default;
 //** Popover border color
-$popover-border-color:                rgba(0,0,0,.2);
+$popover-border-color:                rgba(0,0,0,.2) !default;
 //** Popover fallback border color
-$popover-fallback-border-color:       #999;
+$popover-fallback-border-color:       #999 !default;
 
 //** Popover title background color
-$popover-title-bg:                    $popover-bg;
+$popover-title-bg:                    $popover-bg !default;
 
 //** Popover arrow width
-$popover-arrow-width:                 10px;
+$popover-arrow-width:                 10px !default;
 //** Popover arrow color
-$popover-arrow-color:                 $popover-bg;
+$popover-arrow-color:                 $popover-bg !default;
 
 //** Popover outer arrow width
-$popover-arrow-outer-width:           ($popover-arrow-width + 1);
+$popover-arrow-outer-width:           ($popover-arrow-width + 1) !default;
 //** Popover outer arrow color
-$popover-arrow-outer-color:           fadein($popover-border-color, 5%);
+$popover-arrow-outer-color:           fadein($popover-border-color, 5%) !default;
 //** Popover outer arrow fallback color
-$popover-arrow-outer-fallback-color:  darken($popover-fallback-border-color, 20%);
+$popover-arrow-outer-fallback-color:  darken($popover-fallback-border-color, 20%) !default;
 
 
 //== Labels
@@ -559,22 +559,22 @@ $popover-arrow-outer-fallback-color:  darken($popover-fallback-border-color, 20%
 //##
 
 //** Default label background color
-$label-default-bg:            $btn-default-bg;
+$label-default-bg:            $btn-default-bg !default;
 //** Primary label background color
-$label-primary-bg:            $brand-primary;
+$label-primary-bg:            $brand-primary !default;
 //** Success label background color
-$label-success-bg:            $brand-success;
+$label-success-bg:            $brand-success !default;
 //** Info label background color
-$label-info-bg:               $brand-info;
+$label-info-bg:               $brand-info !default;
 //** Warning label background color
-$label-warning-bg:            $brand-warning;
+$label-warning-bg:            $brand-warning !default;
 //** Danger label background color
-$label-danger-bg:             $brand-danger;
+$label-danger-bg:             $brand-danger !default;
 
 //** Default label text color
-$label-color:                 #fff;
+$label-color:                 #fff !default;
 //** Default text color of a linked label
-$label-link-hover-color:      #fff;
+$label-link-hover-color:      #fff !default;
 
 
 //== Modals
@@ -582,57 +582,57 @@ $label-link-hover-color:      #fff;
 //##
 
 //** Padding applied to the modal body
-$modal-inner-padding:         20px;
+$modal-inner-padding:         20px !default;
 
 //** Padding applied to the modal title
-$modal-title-padding:         15px;
+$modal-title-padding:         15px !default;
 //** Modal title line-height
-$modal-title-line-height:     $line-height-base;
+$modal-title-line-height:     $line-height-base !default;
 
 //** Background color of modal content area
-$modal-content-bg:                             lighten($body-bg, 3%);
+$modal-content-bg:                             lighten($body-bg, 3%) !default;
 //** Modal content border color
-$modal-content-border-color:                   rgba(0,0,0,.2);
+$modal-content-border-color:                   rgba(0,0,0,.2) !default;
 //** Modal content border color **for IE8**
-$modal-content-fallback-border-color:          #999;
+$modal-content-fallback-border-color:          #999 !default;
 
 //** Modal backdrop background color
-$modal-backdrop-bg:           #000;
+$modal-backdrop-bg:           #000 !default;
 //** Modal backdrop opacity
-$modal-backdrop-opacity:      .5;
+$modal-backdrop-opacity:      .5 !default;
 //** Modal header border color
-$modal-header-border-color:   darken($gray-darker, 5%);
+$modal-header-border-color:   darken($gray-darker, 5%) !default;
 //** Modal footer border color
-$modal-footer-border-color:   $modal-header-border-color;
+$modal-footer-border-color:   $modal-header-border-color !default;
 
-$modal-lg:                    900px;
-$modal-md:                    600px;
-$modal-sm:                    300px;
+$modal-lg:                    900px !default;
+$modal-md:                    600px !default;
+$modal-sm:                    300px !default;
 
 
 //== Alerts
 //
 //## Define alert colors, border radius, and padding.
 
-$alert-padding:               15px;
-$alert-border-radius:         $border-radius-base;
-$alert-link-font-weight:      bold;
+$alert-padding:               15px !default;
+$alert-border-radius:         $border-radius-base !default;
+$alert-link-font-weight:      bold !default;
 
-$alert-success-bg:            $state-success-bg;
-$alert-success-text:          $state-success-text;
-$alert-success-border:        $state-success-border;
+$alert-success-bg:            $state-success-bg !default;
+$alert-success-text:          $state-success-text !default;
+$alert-success-border:        $state-success-border !default;
 
-$alert-info-bg:               $state-info-bg;
-$alert-info-text:             $state-info-text;
-$alert-info-border:           $state-info-border;
+$alert-info-bg:               $state-info-bg !default;
+$alert-info-text:             $state-info-text !default;
+$alert-info-border:           $state-info-border !default;
 
-$alert-warning-bg:            $state-warning-bg;
-$alert-warning-text:          $state-warning-text;
-$alert-warning-border:        $state-warning-border;
+$alert-warning-bg:            $state-warning-bg !default;
+$alert-warning-text:          $state-warning-text !default;
+$alert-warning-border:        $state-warning-border !default;
 
-$alert-danger-bg:             $state-danger-bg;
-$alert-danger-text:           $state-danger-text;
-$alert-danger-border:         $state-danger-border;
+$alert-danger-bg:             $state-danger-bg !default;
+$alert-danger-text:           $state-danger-text !default;
+$alert-danger-border:         $state-danger-border !default;
 
 
 //== Progress bars
@@ -640,22 +640,22 @@ $alert-danger-border:         $state-danger-border;
 //##
 
 //** Background color of the whole progress component
-$progress-bg:                 darken($body-bg, 5%);
+$progress-bg:                 darken($body-bg, 5%) !default;
 //** Progress bar text color
-$progress-bar-color:          #fff;
+$progress-bar-color:          #fff !default;
 //** Variable for setting rounded corners on progress bar.
-$progress-border-radius:      $border-radius-base;
+$progress-border-radius:      $border-radius-base !default;
 
 //** Default progress bar color
-$progress-bar-bg:             $brand-primary;
+$progress-bar-bg:             $brand-primary !default;
 //** Success progress bar color
-$progress-bar-success-bg:     $brand-success;
+$progress-bar-success-bg:     $brand-success !default;
 //** Warning progress bar color
-$progress-bar-warning-bg:     $brand-warning;
+$progress-bar-warning-bg:     $brand-warning !default;
 //** Danger progress bar color
-$progress-bar-danger-bg:      $brand-danger;
+$progress-bar-danger-bg:      $brand-danger !default;
 //** Info progress bar color
-$progress-bar-info-bg:        $brand-info;
+$progress-bar-info-bg:        $brand-info !default;
 
 
 //== List group
@@ -663,72 +663,72 @@ $progress-bar-info-bg:        $brand-info;
 //##
 
 //** Background color on `.list-group-item`
-$list-group-bg:                 lighten($body-bg, 5%);
+$list-group-bg:                 lighten($body-bg, 5%) !default;
 //** `.list-group-item` border color
-$list-group-border:             rgba(0, 0, 0, 0.6);
+$list-group-border:             rgba(0, 0, 0, 0.6) !default;
 //** List group border radius
-$list-group-border-radius:      $border-radius-base;
+$list-group-border-radius:      $border-radius-base !default;
 
 //** Background color of single list items on hover
-$list-group-hover-bg:           lighten($body-bg, 10%);
+$list-group-hover-bg:           lighten($body-bg, 10%) !default;
 //** Text color of active list items
-$list-group-active-color:       $component-active-color;
+$list-group-active-color:       $component-active-color !default;
 //** Background color of active list items
-$list-group-active-bg:          lighten($body-bg, 10%);
+$list-group-active-bg:          lighten($body-bg, 10%) !default;
 //** Border color of active list elements
-$list-group-active-border:      $list-group-border;
+$list-group-active-border:      $list-group-border !default;
 //** Text color for content within active list items
-$list-group-active-text-color:  lighten($list-group-active-bg, 40%);
+$list-group-active-text-color:  lighten($list-group-active-bg, 40%) !default;
 
 //** Text color of disabled list items
-$list-group-disabled-color:      $gray-light;
+$list-group-disabled-color:      $gray-light !default;
 //** Background color of disabled list items
-$list-group-disabled-bg:         $gray-lighter;
+$list-group-disabled-bg:         $gray-lighter !default;
 //** Text color for content within disabled list items
-$list-group-disabled-text-color: $list-group-disabled-color;
+$list-group-disabled-text-color: $list-group-disabled-color !default;
 
-$list-group-link-color:         $text-color;
-$list-group-link-hover-color:   $list-group-link-color;
-$list-group-link-heading-color: #fff;
+$list-group-link-color:         $text-color !default;
+$list-group-link-hover-color:   $list-group-link-color !default;
+$list-group-link-heading-color: #fff !default;
 
 
 //== Panels
 //
 //##
 
-$panel-bg:                    lighten($body-bg, 3%);
-$panel-body-padding:          15px;
-$panel-heading-padding:       10px 15px;
-$panel-footer-padding:        $panel-heading-padding;
-$panel-border-radius:         $border-radius-base;
+$panel-bg:                    lighten($body-bg, 3%) !default;
+$panel-body-padding:          15px !default;
+$panel-heading-padding:       10px 15px !default;
+$panel-footer-padding:        $panel-heading-padding !default;
+$panel-border-radius:         $border-radius-base !default;
 
 //** Border color for elements within panels
-$panel-inner-border:          rgba(0, 0, 0, 0.6);
-$panel-footer-bg:             lighten($body-bg, 10%);
+$panel-inner-border:          rgba(0, 0, 0, 0.6) !default;
+$panel-footer-bg:             lighten($body-bg, 10%) !default;
 
-$panel-default-text:          $text-color;
-$panel-default-border:        rgba(0, 0, 0, 0.6);
-$panel-default-heading-bg:    $panel-footer-bg;
+$panel-default-text:          $text-color !default;
+$panel-default-border:        rgba(0, 0, 0, 0.6) !default;
+$panel-default-heading-bg:    $panel-footer-bg !default;
 
-$panel-primary-text:          #fff;
-$panel-primary-border:        $panel-default-border;
-$panel-primary-heading-bg:    $brand-primary;
+$panel-primary-text:          #fff !default;
+$panel-primary-border:        $panel-default-border !default;
+$panel-primary-heading-bg:    $brand-primary !default;
 
-$panel-success-text:          $state-success-text;
-$panel-success-border:        $panel-default-border;
-$panel-success-heading-bg:    $state-success-bg;
+$panel-success-text:          $state-success-text !default;
+$panel-success-border:        $panel-default-border !default;
+$panel-success-heading-bg:    $state-success-bg !default;
 
-$panel-info-text:             $state-info-text;
-$panel-info-border:           $panel-default-border;
-$panel-info-heading-bg:       $state-info-bg;
+$panel-info-text:             $state-info-text !default;
+$panel-info-border:           $panel-default-border !default;
+$panel-info-heading-bg:       $state-info-bg !default;
 
-$panel-warning-text:          $state-warning-text;
-$panel-warning-border:        $panel-default-border;
-$panel-warning-heading-bg:    $state-warning-bg;
+$panel-warning-text:          $state-warning-text !default;
+$panel-warning-border:        $panel-default-border !default;
+$panel-warning-heading-bg:    $state-warning-bg !default;
 
-$panel-danger-text:           $state-danger-text;
-$panel-danger-border:         $panel-default-border;
-$panel-danger-heading-bg:     $state-danger-bg;
+$panel-danger-text:           $state-danger-text !default;
+$panel-danger-border:         $panel-default-border !default;
+$panel-danger-heading-bg:     $state-danger-bg !default;
 
 
 //== Thumbnails
@@ -736,103 +736,103 @@ $panel-danger-heading-bg:     $state-danger-bg;
 //##
 
 //** Padding around the thumbnail image
-$thumbnail-padding:           4px;
+$thumbnail-padding:           4px !default;
 //** Thumbnail background color
-$thumbnail-bg:                darken($body-bg, 5%);
+$thumbnail-bg:                darken($body-bg, 5%) !default;
 //** Thumbnail border color
-$thumbnail-border:            darken($thumbnail-bg, 7%);
+$thumbnail-border:            darken($thumbnail-bg, 7%) !default;
 //** Thumbnail border radius
-$thumbnail-border-radius:     $border-radius-base;
+$thumbnail-border-radius:     $border-radius-base !default;
 
 //** Custom text color for thumbnail captions
-$thumbnail-caption-color:     $text-color;
+$thumbnail-caption-color:     $text-color !default;
 //** Padding around the thumbnail caption
-$thumbnail-caption-padding:   9px;
+$thumbnail-caption-padding:   9px !default;
 
 
 //== Wells
 //
 //##
 
-$well-bg:                     $thumbnail-bg;
-$well-border:                 $thumbnail-border;
+$well-bg:                     $thumbnail-bg !default;
+$well-border:                 $thumbnail-border !default;
 
 
 //== Badges
 //
 //##
 
-$badge-color:                 #fff;
+$badge-color:                 #fff !default;
 //** Linked badge text color on hover
-$badge-link-hover-color:      #fff;
-$badge-bg:                    $gray-light;
+$badge-link-hover-color:      #fff !default;
+$badge-bg:                    $gray-light !default;
 
 //** Badge text color in active nav link
-$badge-active-color:          $link-color;
+$badge-active-color:          $link-color !default;
 //** Badge background color in active nav link
-$badge-active-bg:             $gray-light;
+$badge-active-bg:             $gray-light !default;
 
-$badge-font-weight:           bold;
-$badge-line-height:           1;
-$badge-border-radius:         10px;
+$badge-font-weight:           bold !default;
+$badge-line-height:           1 !default;
+$badge-border-radius:         10px !default;
 
 
 //== Breadcrumbs
 //
 //##
 
-$breadcrumb-padding-vertical:   8px;
-$breadcrumb-padding-horizontal: 15px;
+$breadcrumb-padding-vertical:   8px !default;
+$breadcrumb-padding-horizontal: 15px !default;
 //** Breadcrumb background color
-$breadcrumb-bg:                 transparent;
+$breadcrumb-bg:                 transparent !default;
 //** Breadcrumb text color
-$breadcrumb-color:              #ccc;
+$breadcrumb-color:              #ccc !default;
 //** Text color of current page in the breadcrumb
-$breadcrumb-active-color:       $gray-light;
+$breadcrumb-active-color:       $gray-light !default;
 //** Textual separator for between breadcrumb elements
-$breadcrumb-separator:          "/";
+$breadcrumb-separator:          "/" !default;
 
 
 //== Carousel
 //
 //##
 
-$carousel-text-shadow:                        0 1px 2px rgba(0,0,0,.6);
+$carousel-text-shadow:                        0 1px 2px rgba(0,0,0,.6) !default;
 
-$carousel-control-color:                      #fff;
-$carousel-control-width:                      15%;
-$carousel-control-opacity:                    .5;
-$carousel-control-font-size:                  20px;
+$carousel-control-color:                      #fff !default;
+$carousel-control-width:                      15% !default;
+$carousel-control-opacity:                    .5 !default;
+$carousel-control-font-size:                  20px !default;
 
-$carousel-indicator-active-bg:                #fff;
-$carousel-indicator-border-color:             #fff;
+$carousel-indicator-active-bg:                #fff !default;
+$carousel-indicator-border-color:             #fff !default;
 
-$carousel-caption-color:                      #fff;
+$carousel-caption-color:                      #fff !default;
 
 
 //== Close
 //
 //##
 
-$close-font-weight:           bold;
-$close-color:                 #000;
-$close-text-shadow:           0 1px 0 #fff;
+$close-font-weight:           bold !default;
+$close-color:                 #000 !default;
+$close-text-shadow:           0 1px 0 #fff !default;
 
 
 //== Code
 //
 //##
 
-$code-color:                  #c7254e;
-$code-bg:                     #f9f2f4;
+$code-color:                  #c7254e !default;
+$code-bg:                     #f9f2f4 !default;
 
-$kbd-color:                   #fff;
-$kbd-bg:                      #333;
+$kbd-color:                   #fff !default;
+$kbd-bg:                      #333 !default;
 
-$pre-bg:                      #f5f5f5;
-$pre-color:                   $gray-dark;
-$pre-border-color:            #ccc;
-$pre-scrollable-max-height:   340px;
+$pre-bg:                      #f5f5f5 !default;
+$pre-color:                   $gray-dark !default;
+$pre-border-color:            #ccc !default;
+$pre-scrollable-max-height:   340px !default;
 
 
 //== Type
@@ -840,22 +840,22 @@ $pre-scrollable-max-height:   340px;
 //##
 
 //** Horizontal offset for forms and lists.
-$component-offset-horizontal: 180px;
+$component-offset-horizontal: 180px !default;
 //** Text muted color
-$text-muted:                  $gray-light;
+$text-muted:                  $gray-light !default;
 //** Abbreviations and acronyms border color
-$abbr-border-color:           $gray-light;
+$abbr-border-color:           $gray-light !default;
 //** Headings small color
-$headings-small-color:        $gray-light;
+$headings-small-color:        $gray-light !default;
 //** Blockquote small color
-$blockquote-small-color:      $gray-light;
+$blockquote-small-color:      $gray-light !default;
 //** Blockquote font size
-$blockquote-font-size:        ($font-size-base * 1.25);
+$blockquote-font-size:        ($font-size-base * 1.25) !default;
 //** Blockquote border color
-$blockquote-border-color:     $gray-light;
+$blockquote-border-color:     $gray-light !default;
 //** Page header border color
-$page-header-border-color:    darken($gray-darker, 5%);
+$page-header-border-color:    darken($gray-darker, 5%) !default;
 //** Width of horizontal description list titles
-$dl-horizontal-offset:        $component-offset-horizontal;
+$dl-horizontal-offset:        $component-offset-horizontal !default;
 //** Horizontal line color.
-$hr-border:                   darken($gray-darker, 5%);
+$hr-border:                   darken($gray-darker, 5%) !default;
diff --git a/spacelab/_variables.scss b/spacelab/_variables.scss
index c20cd8f5..7d453acd 100644
--- a/spacelab/_variables.scss
+++ b/spacelab/_variables.scss
@@ -7,18 +7,18 @@
 //
 //## Gray and brand colors for use across Bootstrap.
 
-$gray-base:              #000;
-$gray-darker:            #2d2d2d; // #222
-$gray-dark:              lighten($gray-base, 20%);   // #333
-$gray:                   #666; // #555
-$gray-light:             lighten($gray-base, 60%);   // #999
-$gray-lighter:           lighten($gray-base, 93.5%); // #eee
+$gray-base:              #000 !default;
+$gray-darker:            #2d2d2d !default; // #222
+$gray-dark:              lighten($gray-base, 20%) !default;   // #333
+$gray:                   #666 !default; // #555
+$gray-light:             lighten($gray-base, 60%) !default;   // #999
+$gray-lighter:           lighten($gray-base, 93.5%) !default; // #eee
 
-$brand-primary:         #446E9B;
-$brand-success:         #3CB521;
-$brand-info:            #3399F3;
-$brand-warning:         #D47500;
-$brand-danger:          #CD0200;
+$brand-primary:         #446E9B !default;
+$brand-success:         #3CB521 !default;
+$brand-info:            #3399F3 !default;
+$brand-warning:         #D47500 !default;
+$brand-danger:          #CD0200 !default;
 
 
 //== Scaffolding
@@ -26,49 +26,49 @@ $brand-danger:          #CD0200;
 //## Settings for some of the most global styles.
 
 //** Background color for ``.
-$body-bg:               #fff;
+$body-bg:               #fff !default;
 //** Global text color on ``.
-$text-color:            $gray;
+$text-color:            $gray !default;
 
 //** Global textual link color.
-$link-color:            $brand-info;
+$link-color:            $brand-info !default;
 //** Link hover color set via `darken()` function.
-$link-hover-color:      $link-color;
+$link-hover-color:      $link-color !default;
 //** Link hover decoration.
-$link-hover-decoration: underline;
+$link-hover-decoration: underline !default;
 
 
 //== Typography
 //
 //## Font, line-height, and color for body text, headings, and more.
 
-$font-family-sans-serif:  "Open Sans", "Helvetica Neue", Helvetica, Arial, sans-serif;
-$font-family-serif:       Georgia, "Times New Roman", Times, serif;
+$font-family-sans-serif:  "Open Sans", "Helvetica Neue", Helvetica, Arial, sans-serif !default;
+$font-family-serif:       Georgia, "Times New Roman", Times, serif !default;
 //** Default monospace fonts for ``, ``, and `
`.
-$font-family-monospace:   Menlo, Monaco, Consolas, "Courier New", monospace;
-$font-family-base:        $font-family-sans-serif;
+$font-family-monospace:   Menlo, Monaco, Consolas, "Courier New", monospace !default;
+$font-family-base:        $font-family-sans-serif !default;
 
-$font-size-base:          14px;
-$font-size-large:         ceil(($font-size-base * 1.25)); // ~18px
-$font-size-small:         ceil(($font-size-base * 0.85)); // ~12px
+$font-size-base:          14px !default;
+$font-size-large:         ceil(($font-size-base * 1.25)) !default; // ~18px
+$font-size-small:         ceil(($font-size-base * 0.85)) !default; // ~12px
 
-$font-size-h1:            floor(($font-size-base * 2.6)); // ~36px
-$font-size-h2:            floor(($font-size-base * 2.15)); // ~30px
-$font-size-h3:            ceil(($font-size-base * 1.7)); // ~24px
-$font-size-h4:            ceil(($font-size-base * 1.25)); // ~18px
-$font-size-h5:            $font-size-base;
-$font-size-h6:            ceil(($font-size-base * 0.85)); // ~12px
+$font-size-h1:            floor(($font-size-base * 2.6)) !default; // ~36px
+$font-size-h2:            floor(($font-size-base * 2.15)) !default; // ~30px
+$font-size-h3:            ceil(($font-size-base * 1.7)) !default; // ~24px
+$font-size-h4:            ceil(($font-size-base * 1.25)) !default; // ~18px
+$font-size-h5:            $font-size-base !default;
+$font-size-h6:            ceil(($font-size-base * 0.85)) !default; // ~12px
 
 //** Unit-less `line-height` for use in components like buttons.
-$line-height-base:        1.428571429; // 20/14
+$line-height-base:        1.428571429 !default; // 20/14
 //** Computed "line-height" (`font-size` * `line-height`) for use with `margin`, `padding`, etc.
-$line-height-computed:    floor(($font-size-base * $line-height-base)); // ~20px
+$line-height-computed:    floor(($font-size-base * $line-height-base)) !default; // ~20px
 
 //** By default, this inherits from the ``.
-$headings-font-family:    $font-family-base;
-$headings-font-weight:    500;
-$headings-line-height:    1.1;
-$headings-color:          $gray-darker;
+$headings-font-family:    $font-family-base !default;
+$headings-font-weight:    500 !default;
+$headings-line-height:    1.1 !default;
+$headings-color:          $gray-darker !default;
 
 
 //== Iconography
@@ -76,45 +76,45 @@ $headings-color:          $gray-darker;
 //## Specify custom location and filename of the included Glyphicons icon font. Useful for those including Bootstrap via Bower.
 
 //** Load fonts from this directory.
-$icon-font-path:          "../fonts/";
+$icon-font-path:          "../fonts/" !default;
 //** File name for all font files.
-$icon-font-name:          "glyphicons-halflings-regular";
+$icon-font-name:          "glyphicons-halflings-regular" !default;
 //** Element ID within SVG icon file.
-$icon-font-svg-id:        "glyphicons_halflingsregular";
+$icon-font-svg-id:        "glyphicons_halflingsregular" !default;
 
 
 //== Components
 //
 //## Define common padding and border radius sizes and more. Values based on 14px text and 1.428 line-height (~20px to start).
 
-$padding-base-vertical:     8px;
-$padding-base-horizontal:   12px;
+$padding-base-vertical:     8px !default;
+$padding-base-horizontal:   12px !default;
 
-$padding-large-vertical:    14px;
-$padding-large-horizontal:  16px;
+$padding-large-vertical:    14px !default;
+$padding-large-horizontal:  16px !default;
 
-$padding-small-vertical:    5px;
-$padding-small-horizontal:  10px;
+$padding-small-vertical:    5px !default;
+$padding-small-horizontal:  10px !default;
 
-$padding-xs-vertical:       1px;
-$padding-xs-horizontal:     5px;
+$padding-xs-vertical:       1px !default;
+$padding-xs-horizontal:     5px !default;
 
-$line-height-large:         1.3333333; // extra decimals for Win 8.1 Chrome
-$line-height-small:         1.5;
+$line-height-large:         1.3333333 !default; // extra decimals for Win 8.1 Chrome
+$line-height-small:         1.5 !default;
 
-$border-radius-base:        4px;
-$border-radius-large:       6px;
-$border-radius-small:       3px;
+$border-radius-base:        4px !default;
+$border-radius-large:       6px !default;
+$border-radius-small:       3px !default;
 
 //** Global color for active items (e.g., navs or dropdowns).
-$component-active-color:    #fff;
+$component-active-color:    #fff !default;
 //** Global background color for active items (e.g., navs or dropdowns).
-$component-active-bg:       $brand-primary;
+$component-active-bg:       $brand-primary !default;
 
 //** Width of the `border` for generating carets that indicator dropdowns.
-$caret-width-base:          4px;
+$caret-width-base:          4px !default;
 //** Carets increase slightly in size for larger components.
-$caret-width-large:         5px;
+$caret-width-large:         5px !default;
 
 
 //== Tables
@@ -122,53 +122,53 @@ $caret-width-large:         5px;
 //## Customizes the `.table` component with basic values, each used across all table variations.
 
 //** Padding for ``s and ``s.
-$table-cell-padding:            8px;
+$table-cell-padding:            8px !default;
 //** Padding for cells in `.table-condensed`.
-$table-condensed-cell-padding:  5px;
+$table-condensed-cell-padding:  5px !default;
 
 //** Default background color used for all tables.
-$table-bg:                      transparent;
+$table-bg:                      transparent !default;
 //** Background color used for `.table-striped`.
-$table-bg-accent:               #f9f9f9;
+$table-bg-accent:               #f9f9f9 !default;
 //** Background color used for `.table-hover`.
-$table-bg-hover:                #f5f5f5;
-$table-bg-active:               $table-bg-hover;
+$table-bg-hover:                #f5f5f5 !default;
+$table-bg-active:               $table-bg-hover !default;
 
 //** Border color for table and cell borders.
-$table-border-color:            #ddd;
+$table-border-color:            #ddd !default;
 
 
 //== Buttons
 //
 //## For each of Bootstrap's buttons, define text, background and border color.
 
-$btn-font-weight:                normal;
+$btn-font-weight:                normal !default;
 
-$btn-default-color:              #fff;
-$btn-default-bg:                 #474949;
-$btn-default-border:             $btn-default-bg;
+$btn-default-color:              #fff !default;
+$btn-default-bg:                 #474949 !default;
+$btn-default-border:             $btn-default-bg !default;
 
-$btn-primary-color:              $btn-default-color;
-$btn-primary-bg:                 $brand-primary;
-$btn-primary-border:             $btn-primary-bg;
+$btn-primary-color:              $btn-default-color !default;
+$btn-primary-bg:                 $brand-primary !default;
+$btn-primary-border:             $btn-primary-bg !default;
 
-$btn-success-color:              $btn-default-color;
-$btn-success-bg:                 $brand-success;
-$btn-success-border:             $btn-success-bg;
+$btn-success-color:              $btn-default-color !default;
+$btn-success-bg:                 $brand-success !default;
+$btn-success-border:             $btn-success-bg !default;
 
-$btn-info-color:                 $btn-default-color;
-$btn-info-bg:                    $brand-info;
-$btn-info-border:                $btn-info-bg;
+$btn-info-color:                 $btn-default-color !default;
+$btn-info-bg:                    $brand-info !default;
+$btn-info-border:                $btn-info-bg !default;
 
-$btn-warning-color:              $btn-default-color;
-$btn-warning-bg:                 $brand-warning;
-$btn-warning-border:             $btn-warning-bg;
+$btn-warning-color:              $btn-default-color !default;
+$btn-warning-bg:                 $brand-warning !default;
+$btn-warning-border:             $btn-warning-bg !default;
 
-$btn-danger-color:               $btn-default-color;
-$btn-danger-bg:                  $brand-danger;
-$btn-danger-border:              $btn-danger-bg;
+$btn-danger-color:               $btn-default-color !default;
+$btn-danger-bg:                  $brand-danger !default;
+$btn-danger-border:              $btn-danger-bg !default;
 
-$btn-link-disabled-color:        $gray-light;
+$btn-link-disabled-color:        $gray-light !default;
 
 
 //== Forms
@@ -176,50 +176,50 @@ $btn-link-disabled-color:        $gray-light;
 //##
 
 //** `` background color
-$input-bg:                       #fff;
+$input-bg:                       #fff !default;
 //** `` background color
-$input-bg-disabled:              $gray-lighter;
+$input-bg-disabled:              $gray-lighter !default;
 
 //** Text color for ``s
-$input-color:                    $text-color;
+$input-color:                    $text-color !default;
 //** `` border color
-$input-border:                   #ccc;
+$input-border:                   #ccc !default;
 
 // TODO: Rename `$input-border-radius` to `$input-border-radius-base` in v4
 //** Default `.form-control` border radius
 // This has no effect on ``s in CSS.
-$input-border-radius:            $border-radius-base;
+$input-border-radius:            $border-radius-base !default;
 //** Large `.form-control` border radius
-$input-border-radius-large:      $border-radius-large;
+$input-border-radius-large:      $border-radius-large !default;
 //** Small `.form-control` border radius
-$input-border-radius-small:      $border-radius-small;
+$input-border-radius-small:      $border-radius-small !default;
 
 //** Border color for inputs on focus
-$input-border-focus:             #66afe9;
+$input-border-focus:             #66afe9 !default;
 
 //** Placeholder text color
-$input-color-placeholder:        $gray-light;
+$input-color-placeholder:        $gray-light !default;
 
 //** Default `.form-control` height
-$input-height-base:              ($line-height-computed + ($padding-base-vertical * 2) + 2);
+$input-height-base:              ($line-height-computed + ($padding-base-vertical * 2) + 2) !default;
 //** Large `.form-control` height
-$input-height-large:             (ceil($font-size-large * $line-height-large) + ($padding-large-vertical * 2) + 2);
+$input-height-large:             (ceil($font-size-large * $line-height-large) + ($padding-large-vertical * 2) + 2) !default;
 //** Small `.form-control` height
-$input-height-small:             (floor($font-size-small * $line-height-small) + ($padding-small-vertical * 2) + 2);
+$input-height-small:             (floor($font-size-small * $line-height-small) + ($padding-small-vertical * 2) + 2) !default;
 
 //** `.form-group` margin
-$form-group-margin-bottom:       15px;
+$form-group-margin-bottom:       15px !default;
 
-$legend-color:                   $text-color;
-$legend-border-color:            #e5e5e5;
+$legend-color:                   $text-color !default;
+$legend-border-color:            #e5e5e5 !default;
 
 //** Background color for textual input addons
-$input-group-addon-bg:           $gray-lighter;
+$input-group-addon-bg:           $gray-lighter !default;
 //** Border color for textual input addons
-$input-group-addon-border-color: $input-border;
+$input-group-addon-border-color: $input-border !default;
 
 //** Disabled cursor for form controls and buttons.
-$cursor-disabled:                not-allowed;
+$cursor-disabled:                not-allowed !default;
 
 
 //== Dropdowns
@@ -227,34 +227,34 @@ $cursor-disabled:                not-allowed;
 //## Dropdown menu container and contents.
 
 //** Background for the dropdown menu.
-$dropdown-bg:                    #fff;
+$dropdown-bg:                    #fff !default;
 //** Dropdown menu `border-color`.
-$dropdown-border:                rgba(0,0,0,.15);
+$dropdown-border:                rgba(0,0,0,.15) !default;
 //** Dropdown menu `border-color` **for IE8**.
-$dropdown-fallback-border:       #ccc;
+$dropdown-fallback-border:       #ccc !default;
 //** Divider color for between dropdown items.
-$dropdown-divider-bg:            #e5e5e5;
+$dropdown-divider-bg:            #e5e5e5 !default;
 
 //** Dropdown link text color.
-$dropdown-link-color:            $gray-dark;
+$dropdown-link-color:            $gray-dark !default;
 //** Hover color for dropdown links.
-$dropdown-link-hover-color:      #fff;
+$dropdown-link-hover-color:      #fff !default;
 //** Hover background for dropdown links.
-$dropdown-link-hover-bg:         $component-active-bg;
+$dropdown-link-hover-bg:         $component-active-bg !default;
 
 //** Active dropdown menu item text color.
-$dropdown-link-active-color:     #fff;
+$dropdown-link-active-color:     #fff !default;
 //** Active dropdown menu item background color.
-$dropdown-link-active-bg:        $component-active-bg;
+$dropdown-link-active-bg:        $component-active-bg !default;
 
 //** Disabled dropdown menu item background color.
-$dropdown-link-disabled-color:   $gray-light;
+$dropdown-link-disabled-color:   $gray-light !default;
 
 //** Text color for headers within dropdown menus.
-$dropdown-header-color:          $gray-light;
+$dropdown-header-color:          $gray-light !default;
 
 //** Deprecated `$dropdown-caret-color` as of v3.1.0
-$dropdown-caret-color:           #000;
+$dropdown-caret-color:           #000 !default;
 
 
 //-- Z-index master list
@@ -264,13 +264,13 @@ $dropdown-caret-color:           #000;
 //
 // Note: These variables are not generated into the Customizer.
 
-$zindex-navbar:            1000;
-$zindex-dropdown:          1000;
-$zindex-popover:           1060;
-$zindex-tooltip:           1070;
-$zindex-navbar-fixed:      1030;
-$zindex-modal-background:  1040;
-$zindex-modal:             1050;
+$zindex-navbar:            1000 !default;
+$zindex-dropdown:          1000 !default;
+$zindex-popover:           1060 !default;
+$zindex-tooltip:           1070 !default;
+$zindex-navbar-fixed:      1030 !default;
+$zindex-modal-background:  1040 !default;
+$zindex-modal:             1050 !default;
 
 
 //== Media queries breakpoints
@@ -279,37 +279,37 @@ $zindex-modal:             1050;
 
 // Extra small screen / phone
 //** Deprecated `$screen-xs` as of v3.0.1
-$screen-xs:                  480px;
+$screen-xs:                  480px !default;
 //** Deprecated `$screen-xs-min` as of v3.2.0
-$screen-xs-min:              $screen-xs;
+$screen-xs-min:              $screen-xs !default;
 //** Deprecated `$screen-phone` as of v3.0.1
-$screen-phone:               $screen-xs-min;
+$screen-phone:               $screen-xs-min !default;
 
 // Small screen / tablet
 //** Deprecated `$screen-sm` as of v3.0.1
-$screen-sm:                  768px;
-$screen-sm-min:              $screen-sm;
+$screen-sm:                  768px !default;
+$screen-sm-min:              $screen-sm !default;
 //** Deprecated `$screen-tablet` as of v3.0.1
-$screen-tablet:              $screen-sm-min;
+$screen-tablet:              $screen-sm-min !default;
 
 // Medium screen / desktop
 //** Deprecated `$screen-md` as of v3.0.1
-$screen-md:                  992px;
-$screen-md-min:              $screen-md;
+$screen-md:                  992px !default;
+$screen-md-min:              $screen-md !default;
 //** Deprecated `$screen-desktop` as of v3.0.1
-$screen-desktop:             $screen-md-min;
+$screen-desktop:             $screen-md-min !default;
 
 // Large screen / wide desktop
 //** Deprecated `$screen-lg` as of v3.0.1
-$screen-lg:                  1200px;
-$screen-lg-min:              $screen-lg;
+$screen-lg:                  1200px !default;
+$screen-lg-min:              $screen-lg !default;
 //** Deprecated `$screen-lg-desktop` as of v3.0.1
-$screen-lg-desktop:          $screen-lg-min;
+$screen-lg-desktop:          $screen-lg-min !default;
 
 // So media queries don't overlap when required, provide a maximum
-$screen-xs-max:              ($screen-sm-min - 1);
-$screen-sm-max:              ($screen-md-min - 1);
-$screen-md-max:              ($screen-lg-min - 1);
+$screen-xs-max:              ($screen-sm-min - 1) !default;
+$screen-sm-max:              ($screen-md-min - 1) !default;
+$screen-md-max:              ($screen-lg-min - 1) !default;
 
 
 //== Grid system
@@ -317,14 +317,14 @@ $screen-md-max:              ($screen-lg-min - 1);
 //## Define your custom responsive grid.
 
 //** Number of columns in the grid.
-$grid-columns:              12;
+$grid-columns:              12 !default;
 //** Padding between columns. Gets divided in half for the left and right.
-$grid-gutter-width:         30px;
+$grid-gutter-width:         30px !default;
 // Navbar collapse
 //** Point at which the navbar becomes uncollapsed.
-$grid-float-breakpoint:     $screen-sm-min;
+$grid-float-breakpoint:     $screen-sm-min !default;
 //** Point at which the navbar begins collapsing.
-$grid-float-breakpoint-max: ($grid-float-breakpoint - 1);
+$grid-float-breakpoint-max: ($grid-float-breakpoint - 1) !default;
 
 
 //== Container sizes
@@ -332,19 +332,19 @@ $grid-float-breakpoint-max: ($grid-float-breakpoint - 1);
 //## Define the maximum width of `.container` for different screen sizes.
 
 // Small screen / tablet
-$container-tablet:             (720px + $grid-gutter-width);
+$container-tablet:             (720px + $grid-gutter-width) !default;
 //** For `$screen-sm-min` and up.
-$container-sm:                 $container-tablet;
+$container-sm:                 $container-tablet !default;
 
 // Medium screen / desktop
-$container-desktop:            (940px + $grid-gutter-width);
+$container-desktop:            (940px + $grid-gutter-width) !default;
 //** For `$screen-md-min` and up.
-$container-md:                 $container-desktop;
+$container-md:                 $container-desktop !default;
 
 // Large screen / wide desktop
-$container-large-desktop:      (1140px + $grid-gutter-width);
+$container-large-desktop:      (1140px + $grid-gutter-width) !default;
 //** For `$screen-lg-min` and up.
-$container-lg:                 $container-large-desktop;
+$container-lg:                 $container-large-desktop !default;
 
 
 //== Navbar
@@ -352,61 +352,61 @@ $container-lg:                 $container-large-desktop;
 //##
 
 // Basics of a navbar
-$navbar-height:                    50px;
-$navbar-margin-bottom:             $line-height-computed;
-$navbar-border-radius:             $border-radius-base;
-$navbar-padding-horizontal:        floor(($grid-gutter-width / 2));
-$navbar-padding-vertical:          (($navbar-height - $line-height-computed) / 2);
-$navbar-collapse-max-height:       340px;
+$navbar-height:                    50px !default;
+$navbar-margin-bottom:             $line-height-computed !default;
+$navbar-border-radius:             $border-radius-base !default;
+$navbar-padding-horizontal:        floor(($grid-gutter-width / 2)) !default;
+$navbar-padding-vertical:          (($navbar-height - $line-height-computed) / 2) !default;
+$navbar-collapse-max-height:       340px !default;
 
-$navbar-default-color:             #777;
-$navbar-default-bg:                #eee;
-$navbar-default-border:            darken($navbar-default-bg, 6.5%);
+$navbar-default-color:             #777 !default;
+$navbar-default-bg:                #eee !default;
+$navbar-default-border:            darken($navbar-default-bg, 6.5%) !default;
 
 // Navbar links
-$navbar-default-link-color:                #777;
-$navbar-default-link-hover-color:          $brand-info;
-$navbar-default-link-hover-bg:             transparent;
-$navbar-default-link-active-color:         $navbar-default-link-hover-color;
-$navbar-default-link-active-bg:            transparent;
-$navbar-default-link-disabled-color:       #444;
-$navbar-default-link-disabled-bg:          transparent;
+$navbar-default-link-color:                #777 !default;
+$navbar-default-link-hover-color:          $brand-info !default;
+$navbar-default-link-hover-bg:             transparent !default;
+$navbar-default-link-active-color:         $navbar-default-link-hover-color !default;
+$navbar-default-link-active-bg:            transparent !default;
+$navbar-default-link-disabled-color:       #444 !default;
+$navbar-default-link-disabled-bg:          transparent !default;
 
 // Navbar brand label
-$navbar-default-brand-color:               $navbar-default-link-color;
-$navbar-default-brand-hover-color:         $navbar-default-link-hover-color;
-$navbar-default-brand-hover-bg:            transparent;
+$navbar-default-brand-color:               $navbar-default-link-color !default;
+$navbar-default-brand-hover-color:         $navbar-default-link-hover-color !default;
+$navbar-default-brand-hover-bg:            transparent !default;
 
 // Navbar toggle
-$navbar-default-toggle-hover-bg:           darken($navbar-default-bg, 6.5%);
-$navbar-default-toggle-icon-bar-bg:        #ccc;
-$navbar-default-toggle-border-color:       darken($navbar-default-bg, 6.5%);
+$navbar-default-toggle-hover-bg:           darken($navbar-default-bg, 6.5%) !default;
+$navbar-default-toggle-icon-bar-bg:        #ccc !default;
+$navbar-default-toggle-border-color:       darken($navbar-default-bg, 6.5%) !default;
 
 
 // Inverted navbar
 // Reset inverted navbar basics
-$navbar-inverse-color:                      #ddd;
-$navbar-inverse-bg:                         $brand-primary;
-$navbar-inverse-border:                     darken($navbar-inverse-bg, 10%);
+$navbar-inverse-color:                      #ddd !default;
+$navbar-inverse-bg:                         $brand-primary !default;
+$navbar-inverse-border:                     darken($navbar-inverse-bg, 10%) !default;
 
 // Inverted navbar links
-$navbar-inverse-link-color:                 #ddd;
-$navbar-inverse-link-hover-color:           #fff;
-$navbar-inverse-link-hover-bg:              transparent;
-$navbar-inverse-link-active-color:          $navbar-inverse-link-hover-color;
-$navbar-inverse-link-active-bg:             transparent;
-$navbar-inverse-link-disabled-color:        #ccc;
-$navbar-inverse-link-disabled-bg:           transparent;
+$navbar-inverse-link-color:                 #ddd !default;
+$navbar-inverse-link-hover-color:           #fff !default;
+$navbar-inverse-link-hover-bg:              transparent !default;
+$navbar-inverse-link-active-color:          $navbar-inverse-link-hover-color !default;
+$navbar-inverse-link-active-bg:             transparent !default;
+$navbar-inverse-link-disabled-color:        #ccc !default;
+$navbar-inverse-link-disabled-bg:           transparent !default;
 
 // Inverted navbar brand label
-$navbar-inverse-brand-color:                $navbar-inverse-link-color;
-$navbar-inverse-brand-hover-color:          #fff;
-$navbar-inverse-brand-hover-bg:             transparent;
+$navbar-inverse-brand-color:                $navbar-inverse-link-color !default;
+$navbar-inverse-brand-hover-color:          #fff !default;
+$navbar-inverse-brand-hover-bg:             transparent !default;
 
 // Inverted navbar toggle
-$navbar-inverse-toggle-hover-bg:            darken($navbar-inverse-bg, 10%);
-$navbar-inverse-toggle-icon-bar-bg:         #fff;
-$navbar-inverse-toggle-border-color:        darken($navbar-inverse-bg, 10%);
+$navbar-inverse-toggle-hover-bg:            darken($navbar-inverse-bg, 10%) !default;
+$navbar-inverse-toggle-icon-bar-bg:         #fff !default;
+$navbar-inverse-toggle-border-color:        darken($navbar-inverse-bg, 10%) !default;
 
 
 //== Navs
@@ -414,97 +414,97 @@ $navbar-inverse-toggle-border-color:        darken($navbar-inverse-bg, 10%);
 //##
 
 //=== Shared nav styles
-$nav-link-padding:                          10px 15px;
-$nav-link-hover-bg:                         $gray-lighter;
+$nav-link-padding:                          10px 15px !default;
+$nav-link-hover-bg:                         $gray-lighter !default;
 
-$nav-disabled-link-color:                   $gray-light;
-$nav-disabled-link-hover-color:             $gray-light;
+$nav-disabled-link-color:                   $gray-light !default;
+$nav-disabled-link-hover-color:             $gray-light !default;
 
 //== Tabs
-$nav-tabs-border-color:                     #ddd;
+$nav-tabs-border-color:                     #ddd !default;
 
-$nav-tabs-link-hover-border-color:          $gray-lighter;
+$nav-tabs-link-hover-border-color:          $gray-lighter !default;
 
-$nav-tabs-active-link-hover-bg:             $body-bg;
-$nav-tabs-active-link-hover-color:          $gray;
-$nav-tabs-active-link-hover-border-color:   #ddd;
+$nav-tabs-active-link-hover-bg:             $body-bg !default;
+$nav-tabs-active-link-hover-color:          $gray !default;
+$nav-tabs-active-link-hover-border-color:   #ddd !default;
 
-$nav-tabs-justified-link-border-color:            #ddd;
-$nav-tabs-justified-active-link-border-color:     $body-bg;
+$nav-tabs-justified-link-border-color:            #ddd !default;
+$nav-tabs-justified-active-link-border-color:     $body-bg !default;
 
 //== Pills
-$nav-pills-border-radius:                   $border-radius-base;
-$nav-pills-active-link-hover-bg:            $component-active-bg;
-$nav-pills-active-link-hover-color:         $component-active-color;
+$nav-pills-border-radius:                   $border-radius-base !default;
+$nav-pills-active-link-hover-bg:            $component-active-bg !default;
+$nav-pills-active-link-hover-color:         $component-active-color !default;
 
 
 //== Pagination
 //
 //##
 
-$pagination-color:                     $link-color;
-$pagination-bg:                        #fff;
-$pagination-border:                    #ddd;
+$pagination-color:                     $link-color !default;
+$pagination-bg:                        #fff !default;
+$pagination-border:                    #ddd !default;
 
-$pagination-hover-color:               $link-hover-color;
-$pagination-hover-bg:                  $gray-lighter;
-$pagination-hover-border:              #ddd;
+$pagination-hover-color:               $link-hover-color !default;
+$pagination-hover-bg:                  $gray-lighter !default;
+$pagination-hover-border:              #ddd !default;
 
-$pagination-active-color:              $gray-light;
-$pagination-active-bg:                 #f5f5f5;
-$pagination-active-border:             #ddd;
+$pagination-active-color:              $gray-light !default;
+$pagination-active-bg:                 #f5f5f5 !default;
+$pagination-active-border:             #ddd !default;
 
-$pagination-disabled-color:            $gray-light;
-$pagination-disabled-bg:               #fff;
-$pagination-disabled-border:           #ddd;
+$pagination-disabled-color:            $gray-light !default;
+$pagination-disabled-bg:               #fff !default;
+$pagination-disabled-border:           #ddd !default;
 
 
 //== Pager
 //
 //##
 
-$pager-bg:                             $pagination-bg;
-$pager-border:                         $pagination-border;
-$pager-border-radius:                  15px;
+$pager-bg:                             $pagination-bg !default;
+$pager-border:                         $pagination-border !default;
+$pager-border-radius:                  15px !default;
 
-$pager-hover-bg:                       $pagination-hover-bg;
+$pager-hover-bg:                       $pagination-hover-bg !default;
 
-$pager-active-bg:                      $pagination-active-bg;
-$pager-active-color:                   $pagination-active-color;
+$pager-active-bg:                      $pagination-active-bg !default;
+$pager-active-color:                   $pagination-active-color !default;
 
-$pager-disabled-color:                 $gray-light;
+$pager-disabled-color:                 $gray-light !default;
 
 
 //== Jumbotron
 //
 //##
 
-$jumbotron-padding:              30px;
-$jumbotron-color:                inherit;
-$jumbotron-bg:                   $gray-lighter;
-$jumbotron-heading-color:        inherit;
-$jumbotron-font-size:            ceil(($font-size-base * 1.5));
+$jumbotron-padding:              30px !default;
+$jumbotron-color:                inherit !default;
+$jumbotron-bg:                   $gray-lighter !default;
+$jumbotron-heading-color:        inherit !default;
+$jumbotron-font-size:            ceil(($font-size-base * 1.5)) !default;
 
 
 //== Form states and alerts
 //
 //## Define colors for form feedback states and, by default, alerts.
 
-$state-success-text:             #468847;
-$state-success-bg:               #dff0d8;
-$state-success-border:           darken(adjust-hue($state-success-bg, -10), 5%);
+$state-success-text:             #468847 !default;
+$state-success-bg:               #dff0d8 !default;
+$state-success-border:           darken(adjust-hue($state-success-bg, -10), 5%) !default;
 
-$state-info-text:                #3a87ad;
-$state-info-bg:                  #d9edf7;
-$state-info-border:              darken(adjust-hue($state-info-bg, -10), 7%);
+$state-info-text:                #3a87ad !default;
+$state-info-bg:                  #d9edf7 !default;
+$state-info-border:              darken(adjust-hue($state-info-bg, -10), 7%) !default;
 
-$state-warning-text:             #c09853;
-$state-warning-bg:               #fcf8e3;
-$state-warning-border:           darken(adjust-hue($state-warning-bg, -10), 3%);
+$state-warning-text:             #c09853 !default;
+$state-warning-bg:               #fcf8e3 !default;
+$state-warning-border:           darken(adjust-hue($state-warning-bg, -10), 3%) !default;
 
-$state-danger-text:              #b94a48;
-$state-danger-bg:                #f2dede;
-$state-danger-border:            darken(adjust-hue($state-danger-bg, -10), 3%);
+$state-danger-text:              #b94a48 !default;
+$state-danger-bg:                #f2dede !default;
+$state-danger-border:            darken(adjust-hue($state-danger-bg, -10), 3%) !default;
 
 
 //== Tooltips
@@ -512,17 +512,17 @@ $state-danger-border:            darken(adjust-hue($state-danger-bg, -10), 3%);
 //##
 
 //** Tooltip max width
-$tooltip-max-width:           200px;
+$tooltip-max-width:           200px !default;
 //** Tooltip text color
-$tooltip-color:               #fff;
+$tooltip-color:               #fff !default;
 //** Tooltip background color
-$tooltip-bg:                  #000;
-$tooltip-opacity:             .9;
+$tooltip-bg:                  #000 !default;
+$tooltip-opacity:             .9 !default;
 
 //** Tooltip arrow width
-$tooltip-arrow-width:         5px;
+$tooltip-arrow-width:         5px !default;
 //** Tooltip arrow color
-$tooltip-arrow-color:         $tooltip-bg;
+$tooltip-arrow-color:         $tooltip-bg !default;
 
 
 //== Popovers
@@ -530,28 +530,28 @@ $tooltip-arrow-color:         $tooltip-bg;
 //##
 
 //** Popover body background color
-$popover-bg:                          #fff;
+$popover-bg:                          #fff !default;
 //** Popover maximum width
-$popover-max-width:                   276px;
+$popover-max-width:                   276px !default;
 //** Popover border color
-$popover-border-color:                rgba(0,0,0,.2);
+$popover-border-color:                rgba(0,0,0,.2) !default;
 //** Popover fallback border color
-$popover-fallback-border-color:       #ccc;
+$popover-fallback-border-color:       #ccc !default;
 
 //** Popover title background color
-$popover-title-bg:                    darken($popover-bg, 3%);
+$popover-title-bg:                    darken($popover-bg, 3%) !default;
 
 //** Popover arrow width
-$popover-arrow-width:                 10px;
+$popover-arrow-width:                 10px !default;
 //** Popover arrow color
-$popover-arrow-color:                 $popover-bg;
+$popover-arrow-color:                 $popover-bg !default;
 
 //** Popover outer arrow width
-$popover-arrow-outer-width:           ($popover-arrow-width + 1);
+$popover-arrow-outer-width:           ($popover-arrow-width + 1) !default;
 //** Popover outer arrow color
-$popover-arrow-outer-color:           fadein($popover-border-color, 5%);
+$popover-arrow-outer-color:           fadein($popover-border-color, 5%) !default;
 //** Popover outer arrow fallback color
-$popover-arrow-outer-fallback-color:  darken($popover-fallback-border-color, 20%);
+$popover-arrow-outer-fallback-color:  darken($popover-fallback-border-color, 20%) !default;
 
 
 //== Labels
@@ -559,22 +559,22 @@ $popover-arrow-outer-fallback-color:  darken($popover-fallback-border-color, 20%
 //##
 
 //** Default label background color
-$label-default-bg:            $btn-default-bg;
+$label-default-bg:            $btn-default-bg !default;
 //** Primary label background color
-$label-primary-bg:            $brand-primary;
+$label-primary-bg:            $brand-primary !default;
 //** Success label background color
-$label-success-bg:            $brand-success;
+$label-success-bg:            $brand-success !default;
 //** Info label background color
-$label-info-bg:               $brand-info;
+$label-info-bg:               $brand-info !default;
 //** Warning label background color
-$label-warning-bg:            $brand-warning;
+$label-warning-bg:            $brand-warning !default;
 //** Danger label background color
-$label-danger-bg:             $brand-danger;
+$label-danger-bg:             $brand-danger !default;
 
 //** Default label text color
-$label-color:                 #fff;
+$label-color:                 #fff !default;
 //** Default text color of a linked label
-$label-link-hover-color:      #fff;
+$label-link-hover-color:      #fff !default;
 
 
 //== Modals
@@ -582,57 +582,57 @@ $label-link-hover-color:      #fff;
 //##
 
 //** Padding applied to the modal body
-$modal-inner-padding:         20px;
+$modal-inner-padding:         20px !default;
 
 //** Padding applied to the modal title
-$modal-title-padding:         15px;
+$modal-title-padding:         15px !default;
 //** Modal title line-height
-$modal-title-line-height:     $line-height-base;
+$modal-title-line-height:     $line-height-base !default;
 
 //** Background color of modal content area
-$modal-content-bg:                             #fff;
+$modal-content-bg:                             #fff !default;
 //** Modal content border color
-$modal-content-border-color:                   rgba(0,0,0,.2);
+$modal-content-border-color:                   rgba(0,0,0,.2) !default;
 //** Modal content border color **for IE8**
-$modal-content-fallback-border-color:          #999;
+$modal-content-fallback-border-color:          #999 !default;
 
 //** Modal backdrop background color
-$modal-backdrop-bg:           #000;
+$modal-backdrop-bg:           #000 !default;
 //** Modal backdrop opacity
-$modal-backdrop-opacity:      .5;
+$modal-backdrop-opacity:      .5 !default;
 //** Modal header border color
-$modal-header-border-color:   #e5e5e5;
+$modal-header-border-color:   #e5e5e5 !default;
 //** Modal footer border color
-$modal-footer-border-color:   $modal-header-border-color;
+$modal-footer-border-color:   $modal-header-border-color !default;
 
-$modal-lg:                    900px;
-$modal-md:                    600px;
-$modal-sm:                    300px;
+$modal-lg:                    900px !default;
+$modal-md:                    600px !default;
+$modal-sm:                    300px !default;
 
 
 //== Alerts
 //
 //## Define alert colors, border radius, and padding.
 
-$alert-padding:               15px;
-$alert-border-radius:         $border-radius-base;
-$alert-link-font-weight:      bold;
+$alert-padding:               15px !default;
+$alert-border-radius:         $border-radius-base !default;
+$alert-link-font-weight:      bold !default;
 
-$alert-success-bg:            $state-success-bg;
-$alert-success-text:          $state-success-text;
-$alert-success-border:        $state-success-border;
+$alert-success-bg:            $state-success-bg !default;
+$alert-success-text:          $state-success-text !default;
+$alert-success-border:        $state-success-border !default;
 
-$alert-info-bg:               $state-info-bg;
-$alert-info-text:             $state-info-text;
-$alert-info-border:           $state-info-border;
+$alert-info-bg:               $state-info-bg !default;
+$alert-info-text:             $state-info-text !default;
+$alert-info-border:           $state-info-border !default;
 
-$alert-warning-bg:            $state-warning-bg;
-$alert-warning-text:          $state-warning-text;
-$alert-warning-border:        $state-warning-border;
+$alert-warning-bg:            $state-warning-bg !default;
+$alert-warning-text:          $state-warning-text !default;
+$alert-warning-border:        $state-warning-border !default;
 
-$alert-danger-bg:             $state-danger-bg;
-$alert-danger-text:           $state-danger-text;
-$alert-danger-border:         $state-danger-border;
+$alert-danger-bg:             $state-danger-bg !default;
+$alert-danger-text:           $state-danger-text !default;
+$alert-danger-border:         $state-danger-border !default;
 
 
 //== Progress bars
@@ -640,22 +640,22 @@ $alert-danger-border:         $state-danger-border;
 //##
 
 //** Background color of the whole progress component
-$progress-bg:                 #f5f5f5;
+$progress-bg:                 #f5f5f5 !default;
 //** Progress bar text color
-$progress-bar-color:          #fff;
+$progress-bar-color:          #fff !default;
 //** Variable for setting rounded corners on progress bar.
-$progress-border-radius:      $border-radius-base;
+$progress-border-radius:      $border-radius-base !default;
 
 //** Default progress bar color
-$progress-bar-bg:             $brand-primary;
+$progress-bar-bg:             $brand-primary !default;
 //** Success progress bar color
-$progress-bar-success-bg:     $brand-success;
+$progress-bar-success-bg:     $brand-success !default;
 //** Warning progress bar color
-$progress-bar-warning-bg:     $brand-warning;
+$progress-bar-warning-bg:     $brand-warning !default;
 //** Danger progress bar color
-$progress-bar-danger-bg:      $brand-danger;
+$progress-bar-danger-bg:      $brand-danger !default;
 //** Info progress bar color
-$progress-bar-info-bg:        $brand-info;
+$progress-bar-info-bg:        $brand-info !default;
 
 
 //== List group
@@ -663,72 +663,72 @@ $progress-bar-info-bg:        $brand-info;
 //##
 
 //** Background color on `.list-group-item`
-$list-group-bg:                 #fff;
+$list-group-bg:                 #fff !default;
 //** `.list-group-item` border color
-$list-group-border:             #ddd;
+$list-group-border:             #ddd !default;
 //** List group border radius
-$list-group-border-radius:      $border-radius-base;
+$list-group-border-radius:      $border-radius-base !default;
 
 //** Background color of single list items on hover
-$list-group-hover-bg:           #f5f5f5;
+$list-group-hover-bg:           #f5f5f5 !default;
 //** Text color of active list items
-$list-group-active-color:       $component-active-color;
+$list-group-active-color:       $component-active-color !default;
 //** Background color of active list items
-$list-group-active-bg:          $component-active-bg;
+$list-group-active-bg:          $component-active-bg !default;
 //** Border color of active list elements
-$list-group-active-border:      $list-group-active-bg;
+$list-group-active-border:      $list-group-active-bg !default;
 //** Text color for content within active list items
-$list-group-active-text-color:  lighten($list-group-active-bg, 40%);
+$list-group-active-text-color:  lighten($list-group-active-bg, 40%) !default;
 
 //** Text color of disabled list items
-$list-group-disabled-color:      $gray-light;
+$list-group-disabled-color:      $gray-light !default;
 //** Background color of disabled list items
-$list-group-disabled-bg:         $gray-lighter;
+$list-group-disabled-bg:         $gray-lighter !default;
 //** Text color for content within disabled list items
-$list-group-disabled-text-color: $list-group-disabled-color;
+$list-group-disabled-text-color: $list-group-disabled-color !default;
 
-$list-group-link-color:         #555;
-$list-group-link-hover-color:   $list-group-link-color;
-$list-group-link-heading-color: #333;
+$list-group-link-color:         #555 !default;
+$list-group-link-hover-color:   $list-group-link-color !default;
+$list-group-link-heading-color: #333 !default;
 
 
 //== Panels
 //
 //##
 
-$panel-bg:                    #fff;
-$panel-body-padding:          15px;
-$panel-heading-padding:       10px 15px;
-$panel-footer-padding:        $panel-heading-padding;
-$panel-border-radius:         $border-radius-base;
+$panel-bg:                    #fff !default;
+$panel-body-padding:          15px !default;
+$panel-heading-padding:       10px 15px !default;
+$panel-footer-padding:        $panel-heading-padding !default;
+$panel-border-radius:         $border-radius-base !default;
 
 //** Border color for elements within panels
-$panel-inner-border:          #ddd;
-$panel-footer-bg:             #f5f5f5;
+$panel-inner-border:          #ddd !default;
+$panel-footer-bg:             #f5f5f5 !default;
 
-$panel-default-text:          $gray-dark;
-$panel-default-border:        #ddd;
-$panel-default-heading-bg:    #f5f5f5;
+$panel-default-text:          $gray-dark !default;
+$panel-default-border:        #ddd !default;
+$panel-default-heading-bg:    #f5f5f5 !default;
 
-$panel-primary-text:          #fff;
-$panel-primary-border:        $brand-primary;
-$panel-primary-heading-bg:    $brand-primary;
+$panel-primary-text:          #fff !default;
+$panel-primary-border:        $brand-primary !default;
+$panel-primary-heading-bg:    $brand-primary !default;
 
-$panel-success-text:          $state-success-text;
-$panel-success-border:        $state-success-border;
-$panel-success-heading-bg:    $state-success-bg;
+$panel-success-text:          $state-success-text !default;
+$panel-success-border:        $state-success-border !default;
+$panel-success-heading-bg:    $state-success-bg !default;
 
-$panel-info-text:             $state-info-text;
-$panel-info-border:           $state-info-border;
-$panel-info-heading-bg:       $state-info-bg;
+$panel-info-text:             $state-info-text !default;
+$panel-info-border:           $state-info-border !default;
+$panel-info-heading-bg:       $state-info-bg !default;
 
-$panel-warning-text:          $state-warning-text;
-$panel-warning-border:        $state-warning-border;
-$panel-warning-heading-bg:    $state-warning-bg;
+$panel-warning-text:          $state-warning-text !default;
+$panel-warning-border:        $state-warning-border !default;
+$panel-warning-heading-bg:    $state-warning-bg !default;
 
-$panel-danger-text:           $state-danger-text;
-$panel-danger-border:         $state-danger-border;
-$panel-danger-heading-bg:     $state-danger-bg;
+$panel-danger-text:           $state-danger-text !default;
+$panel-danger-border:         $state-danger-border !default;
+$panel-danger-heading-bg:     $state-danger-bg !default;
 
 
 //== Thumbnails
@@ -736,103 +736,103 @@ $panel-danger-heading-bg:     $state-danger-bg;
 //##
 
 //** Padding around the thumbnail image
-$thumbnail-padding:           4px;
+$thumbnail-padding:           4px !default;
 //** Thumbnail background color
-$thumbnail-bg:                $body-bg;
+$thumbnail-bg:                $body-bg !default;
 //** Thumbnail border color
-$thumbnail-border:            #ddd;
+$thumbnail-border:            #ddd !default;
 //** Thumbnail border radius
-$thumbnail-border-radius:     $border-radius-base;
+$thumbnail-border-radius:     $border-radius-base !default;
 
 //** Custom text color for thumbnail captions
-$thumbnail-caption-color:     $text-color;
+$thumbnail-caption-color:     $text-color !default;
 //** Padding around the thumbnail caption
-$thumbnail-caption-padding:   9px;
+$thumbnail-caption-padding:   9px !default;
 
 
 //== Wells
 //
 //##
 
-$well-bg:                     #f5f5f5;
-$well-border:                 darken($well-bg, 7%);
+$well-bg:                     #f5f5f5 !default;
+$well-border:                 darken($well-bg, 7%) !default;
 
 
 //== Badges
 //
 //##
 
-$badge-color:                 #fff;
+$badge-color:                 #fff !default;
 //** Linked badge text color on hover
-$badge-link-hover-color:      #fff;
-$badge-bg:                    $link-color;
+$badge-link-hover-color:      #fff !default;
+$badge-bg:                    $link-color !default;
 
 //** Badge text color in active nav link
-$badge-active-color:          $link-color;
+$badge-active-color:          $link-color !default;
 //** Badge background color in active nav link
-$badge-active-bg:             #fff;
+$badge-active-bg:             #fff !default;
 
-$badge-font-weight:           bold;
-$badge-line-height:           1;
-$badge-border-radius:         10px;
+$badge-font-weight:           bold !default;
+$badge-line-height:           1 !default;
+$badge-border-radius:         10px !default;
 
 
 //== Breadcrumbs
 //
 //##
 
-$breadcrumb-padding-vertical:   8px;
-$breadcrumb-padding-horizontal: 15px;
+$breadcrumb-padding-vertical:   8px !default;
+$breadcrumb-padding-horizontal: 15px !default;
 //** Breadcrumb background color
-$breadcrumb-bg:                 #f5f5f5;
+$breadcrumb-bg:                 #f5f5f5 !default;
 //** Breadcrumb text color
-$breadcrumb-color:              #ccc;
+$breadcrumb-color:              #ccc !default;
 //** Text color of current page in the breadcrumb
-$breadcrumb-active-color:       $gray-light;
+$breadcrumb-active-color:       $gray-light !default;
 //** Textual separator for between breadcrumb elements
-$breadcrumb-separator:          "/";
+$breadcrumb-separator:          "/" !default;
 
 
 //== Carousel
 //
 //##
 
-$carousel-text-shadow:                        0 1px 2px rgba(0,0,0,.6);
+$carousel-text-shadow:                        0 1px 2px rgba(0,0,0,.6) !default;
 
-$carousel-control-color:                      #fff;
-$carousel-control-width:                      15%;
-$carousel-control-opacity:                    .5;
-$carousel-control-font-size:                  20px;
+$carousel-control-color:                      #fff !default;
+$carousel-control-width:                      15% !default;
+$carousel-control-opacity:                    .5 !default;
+$carousel-control-font-size:                  20px !default;
 
-$carousel-indicator-active-bg:                #fff;
-$carousel-indicator-border-color:             #fff;
+$carousel-indicator-active-bg:                #fff !default;
+$carousel-indicator-border-color:             #fff !default;
 
-$carousel-caption-color:                      #fff;
+$carousel-caption-color:                      #fff !default;
 
 
 //== Close
 //
 //##
 
-$close-font-weight:           bold;
-$close-color:                 #000;
-$close-text-shadow:           0 1px 0 #fff;
+$close-font-weight:           bold !default;
+$close-color:                 #000 !default;
+$close-text-shadow:           0 1px 0 #fff !default;
 
 
 //== Code
 //
 //##
 
-$code-color:                  #c7254e;
-$code-bg:                     #f9f2f4;
+$code-color:                  #c7254e !default;
+$code-bg:                     #f9f2f4 !default;
 
-$kbd-color:                   #fff;
-$kbd-bg:                      #333;
+$kbd-color:                   #fff !default;
+$kbd-bg:                      #333 !default;
 
-$pre-bg:                      #f5f5f5;
-$pre-color:                   $gray-dark;
-$pre-border-color:            #ccc;
-$pre-scrollable-max-height:   340px;
+$pre-bg:                      #f5f5f5 !default;
+$pre-color:                   $gray-dark !default;
+$pre-border-color:            #ccc !default;
+$pre-scrollable-max-height:   340px !default;
 
 
 //== Type
@@ -840,22 +840,22 @@ $pre-scrollable-max-height:   340px;
 //##
 
 //** Horizontal offset for forms and lists.
-$component-offset-horizontal: 180px;
+$component-offset-horizontal: 180px !default;
 //** Text muted color
-$text-muted:                  $gray-light;
+$text-muted:                  $gray-light !default;
 //** Abbreviations and acronyms border color
-$abbr-border-color:           $gray-light;
+$abbr-border-color:           $gray-light !default;
 //** Headings small color
-$headings-small-color:        $gray-light;
+$headings-small-color:        $gray-light !default;
 //** Blockquote small color
-$blockquote-small-color:      $gray-light;
+$blockquote-small-color:      $gray-light !default;
 //** Blockquote font size
-$blockquote-font-size:        ($font-size-base * 1.25);
+$blockquote-font-size:        ($font-size-base * 1.25) !default;
 //** Blockquote border color
-$blockquote-border-color:     $gray-lighter;
+$blockquote-border-color:     $gray-lighter !default;
 //** Page header border color
-$page-header-border-color:    $gray-lighter;
+$page-header-border-color:    $gray-lighter !default;
 //** Width of horizontal description list titles
-$dl-horizontal-offset:        $component-offset-horizontal;
+$dl-horizontal-offset:        $component-offset-horizontal !default;
 //** Horizontal line color.
-$hr-border:                   $gray-lighter;
+$hr-border:                   $gray-lighter !default;
diff --git a/superhero/_variables.scss b/superhero/_variables.scss
index b154664d..6de2b1f3 100644
--- a/superhero/_variables.scss
+++ b/superhero/_variables.scss
@@ -7,18 +7,18 @@
 //
 //## Gray and brand colors for use across Bootstrap.
 
-$gray-base:              #000;
-$gray-darker:            lighten($gray-base, 13.5%); // #222
-$gray-dark:              lighten($gray-base, 20%);   // #333
-$gray:                   lighten($gray-base, 33.5%); // #555
-$gray-light:             #4E5D6C;   // #999
-$gray-lighter:           #EBEBEB; // #eee
+$gray-base:              #000 !default;
+$gray-darker:            lighten($gray-base, 13.5%) !default; // #222
+$gray-dark:              lighten($gray-base, 20%) !default;   // #333
+$gray:                   lighten($gray-base, 33.5%) !default; // #555
+$gray-light:             #4E5D6C !default;   // #999
+$gray-lighter:           #EBEBEB !default; // #eee
 
-$brand-primary:         #DF691A;
-$brand-success:         #5cb85c;
-$brand-info:            #5bc0de;
-$brand-warning:         #f0ad4e;
-$brand-danger:          #d9534f;
+$brand-primary:         #DF691A !default;
+$brand-success:         #5cb85c !default;
+$brand-info:            #5bc0de !default;
+$brand-warning:         #f0ad4e !default;
+$brand-danger:          #d9534f !default;
 
 
 //== Scaffolding
@@ -26,49 +26,49 @@ $brand-danger:          #d9534f;
 //## Settings for some of the most global styles.
 
 //** Background color for ``.
-$body-bg:               #2B3E50;
+$body-bg:               #2B3E50 !default;
 //** Global text color on ``.
-$text-color:            $gray-lighter;
+$text-color:            $gray-lighter !default;
 
 //** Global textual link color.
-$link-color:            $brand-primary;
+$link-color:            $brand-primary !default;
 //** Link hover color set via `darken()` function.
-$link-hover-color:      $link-color;
+$link-hover-color:      $link-color !default;
 //** Link hover decoration.
-$link-hover-decoration: underline;
+$link-hover-decoration: underline !default;
 
 
 //== Typography
 //
 //## Font, line-height, and color for body text, headings, and more.
 
-$font-family-sans-serif:  "Lato", "Helvetica Neue", Helvetica, Arial, sans-serif;
-$font-family-serif:       Georgia, "Times New Roman", Times, serif;
+$font-family-sans-serif:  "Lato", "Helvetica Neue", Helvetica, Arial, sans-serif !default;
+$font-family-serif:       Georgia, "Times New Roman", Times, serif !default;
 //** Default monospace fonts for ``, ``, and `
`.
-$font-family-monospace:   Menlo, Monaco, Consolas, "Courier New", monospace;
-$font-family-base:        $font-family-sans-serif;
+$font-family-monospace:   Menlo, Monaco, Consolas, "Courier New", monospace !default;
+$font-family-base:        $font-family-sans-serif !default;
 
-$font-size-base:          15px;
-$font-size-large:         ceil(($font-size-base * 1.25)); // ~18px
-$font-size-small:         ceil(($font-size-base * 0.85)); // ~12px
+$font-size-base:          15px !default;
+$font-size-large:         ceil(($font-size-base * 1.25)) !default; // ~18px
+$font-size-small:         ceil(($font-size-base * 0.85)) !default; // ~12px
 
-$font-size-h1:            floor(($font-size-base * 2.6)); // ~36px
-$font-size-h2:            floor(($font-size-base * 2.15)); // ~30px
-$font-size-h3:            ceil(($font-size-base * 1.7)); // ~24px
-$font-size-h4:            ceil(($font-size-base * 1.25)); // ~18px
-$font-size-h5:            $font-size-base;
-$font-size-h6:            ceil(($font-size-base * 0.85)); // ~12px
+$font-size-h1:            floor(($font-size-base * 2.6)) !default; // ~36px
+$font-size-h2:            floor(($font-size-base * 2.15)) !default; // ~30px
+$font-size-h3:            ceil(($font-size-base * 1.7)) !default; // ~24px
+$font-size-h4:            ceil(($font-size-base * 1.25)) !default; // ~18px
+$font-size-h5:            $font-size-base !default;
+$font-size-h6:            ceil(($font-size-base * 0.85)) !default; // ~12px
 
 //** Unit-less `line-height` for use in components like buttons.
-$line-height-base:        1.428571429; // 20/14
+$line-height-base:        1.428571429 !default; // 20/14
 //** Computed "line-height" (`font-size` * `line-height`) for use with `margin`, `padding`, etc.
-$line-height-computed:    floor(($font-size-base * $line-height-base)); // ~20px
+$line-height-computed:    floor(($font-size-base * $line-height-base)) !default; // ~20px
 
 //** By default, this inherits from the ``.
-$headings-font-family:    inherit;
-$headings-font-weight:    300;
-$headings-line-height:    1.1;
-$headings-color:          inherit;
+$headings-font-family:    inherit !default;
+$headings-font-weight:    300 !default;
+$headings-line-height:    1.1 !default;
+$headings-color:          inherit !default;
 
 
 //== Iconography
@@ -76,45 +76,45 @@ $headings-color:          inherit;
 //## Specify custom location and filename of the included Glyphicons icon font. Useful for those including Bootstrap via Bower.
 
 //** Load fonts from this directory.
-$icon-font-path:          "../fonts/";
+$icon-font-path:          "../fonts/" !default;
 //** File name for all font files.
-$icon-font-name:          "glyphicons-halflings-regular";
+$icon-font-name:          "glyphicons-halflings-regular" !default;
 //** Element ID within SVG icon file.
-$icon-font-svg-id:        "glyphicons_halflingsregular";
+$icon-font-svg-id:        "glyphicons_halflingsregular" !default;
 
 
 //== Components
 //
 //## Define common padding and border radius sizes and more. Values based on 14px text and 1.428 line-height (~20px to start).
 
-$padding-base-vertical:     8px;
-$padding-base-horizontal:   16px;
+$padding-base-vertical:     8px !default;
+$padding-base-horizontal:   16px !default;
 
-$padding-large-vertical:    12px;
-$padding-large-horizontal:  24px;
+$padding-large-vertical:    12px !default;
+$padding-large-horizontal:  24px !default;
 
-$padding-small-vertical:    5px;
-$padding-small-horizontal:  10px;
+$padding-small-vertical:    5px !default;
+$padding-small-horizontal:  10px !default;
 
-$padding-xs-vertical:       1px;
-$padding-xs-horizontal:     5px;
+$padding-xs-vertical:       1px !default;
+$padding-xs-horizontal:     5px !default;
 
-$line-height-large:         1.3333333; // extra decimals for Win 8.1 Chrome
-$line-height-small:         1.5;
+$line-height-large:         1.3333333 !default; // extra decimals for Win 8.1 Chrome
+$line-height-small:         1.5 !default;
 
-$border-radius-base:        0;
-$border-radius-large:       0;
-$border-radius-small:       0;
+$border-radius-base:        0 !default;
+$border-radius-large:       0 !default;
+$border-radius-small:       0 !default;
 
 //** Global color for active items (e.g., navs or dropdowns).
-$component-active-color:    #fff;
+$component-active-color:    #fff !default;
 //** Global background color for active items (e.g., navs or dropdowns).
-$component-active-bg:       $brand-primary;
+$component-active-bg:       $brand-primary !default;
 
 //** Width of the `border` for generating carets that indicator dropdowns.
-$caret-width-base:          4px;
+$caret-width-base:          4px !default;
 //** Carets increase slightly in size for larger components.
-$caret-width-large:         5px;
+$caret-width-large:         5px !default;
 
 
 //== Tables
@@ -122,53 +122,53 @@ $caret-width-large:         5px;
 //## Customizes the `.table` component with basic values, each used across all table variations.
 
 //** Padding for ``s and ``s.
-$table-cell-padding:            6px;
+$table-cell-padding:            6px !default;
 //** Padding for cells in `.table-condensed`.
-$table-condensed-cell-padding:  3px;
+$table-condensed-cell-padding:  3px !default;
 
 //** Default background color used for all tables.
-$table-bg:                      transparent;
+$table-bg:                      transparent !default;
 //** Background color used for `.table-striped`.
-$table-bg-accent:               $gray-light;
+$table-bg-accent:               $gray-light !default;
 //** Background color used for `.table-hover`.
-$table-bg-hover:                darken($gray-light, 3%);
-$table-bg-active:               $table-bg-hover;
+$table-bg-hover:                darken($gray-light, 3%) !default;
+$table-bg-active:               $table-bg-hover !default;
 
 //** Border color for table and cell borders.
-$table-border-color:            $gray-light;  
+$table-border-color:            $gray-light !default;  
 
 
 //== Buttons
 //
 //## For each of Bootstrap's buttons, define text, background and border color.
 
-$btn-font-weight:                normal;
+$btn-font-weight:                normal !default;
 
-$btn-default-color:              #fff;
-$btn-default-bg:                 $gray-light;
-$btn-default-border:             transparent;
+$btn-default-color:              #fff !default;
+$btn-default-bg:                 $gray-light !default;
+$btn-default-border:             transparent !default;
 
-$btn-primary-color:              #fff;
-$btn-primary-bg:                 $brand-primary;
-$btn-primary-border:             transparent;
+$btn-primary-color:              #fff !default;
+$btn-primary-bg:                 $brand-primary !default;
+$btn-primary-border:             transparent !default;
 
-$btn-success-color:              #fff;
-$btn-success-bg:                 $brand-success;
-$btn-success-border:             transparent;
+$btn-success-color:              #fff !default;
+$btn-success-bg:                 $brand-success !default;
+$btn-success-border:             transparent !default;
 
-$btn-info-color:                 #fff;
-$btn-info-bg:                    $brand-info;
-$btn-info-border:                transparent;
+$btn-info-color:                 #fff !default;
+$btn-info-bg:                    $brand-info !default;
+$btn-info-border:                transparent !default;
 
-$btn-warning-color:              #fff;
-$btn-warning-bg:                 $brand-warning;
-$btn-warning-border:             transparent;
+$btn-warning-color:              #fff !default;
+$btn-warning-bg:                 $brand-warning !default;
+$btn-warning-border:             transparent !default;
 
-$btn-danger-color:               #fff;
-$btn-danger-bg:                  $brand-danger;
-$btn-danger-border:              transparent;
+$btn-danger-color:               #fff !default;
+$btn-danger-bg:                  $brand-danger !default;
+$btn-danger-border:              transparent !default;
 
-$btn-link-disabled-color:        $gray-light;
+$btn-link-disabled-color:        $gray-light !default;
 
 
 //== Forms
@@ -176,50 +176,50 @@ $btn-link-disabled-color:        $gray-light;
 //##
 
 //** `` background color
-$input-bg:                       #fff;
+$input-bg:                       #fff !default;
 //** `` background color
-$input-bg-disabled:              $gray-lighter;
+$input-bg-disabled:              $gray-lighter !default;
 
 //** Text color for ``s
-$input-color:                    $body-bg;
+$input-color:                    $body-bg !default;
 //** `` border color
-$input-border:                   transparent;
+$input-border:                   transparent !default;
 
 // TODO: Rename `$input-border-radius` to `$input-border-radius-base` in v4
 //** Default `.form-control` border radius
 // This has no effect on ``s in CSS.
-$input-border-radius:            $border-radius-base;
+$input-border-radius:            $border-radius-base !default;
 //** Large `.form-control` border radius
-$input-border-radius-large:      $border-radius-large;
+$input-border-radius-large:      $border-radius-large !default;
 //** Small `.form-control` border radius
-$input-border-radius-small:      $border-radius-small;
+$input-border-radius-small:      $border-radius-small !default;
 
 //** Border color for inputs on focus
-$input-border-focus:             transparent;
+$input-border-focus:             transparent !default;
 
 //** Placeholder text color
-$input-color-placeholder:        #ccc;
+$input-color-placeholder:        #ccc !default;
 
 //** Default `.form-control` height
-$input-height-base:              ($line-height-computed + ($padding-base-vertical * 2) + 2);
+$input-height-base:              ($line-height-computed + ($padding-base-vertical * 2) + 2) !default;
 //** Large `.form-control` height
-$input-height-large:             (ceil($font-size-large * $line-height-large) + ($padding-large-vertical * 2) + 2);
+$input-height-large:             (ceil($font-size-large * $line-height-large) + ($padding-large-vertical * 2) + 2) !default;
 //** Small `.form-control` height
-$input-height-small:             (floor($font-size-small * $line-height-small) + ($padding-small-vertical * 2) + 2);
+$input-height-small:             (floor($font-size-small * $line-height-small) + ($padding-small-vertical * 2) + 2) !default;
 
 //** `.form-group` margin
-$form-group-margin-bottom:       15px;
+$form-group-margin-bottom:       15px !default;
 
-$legend-color:                   $text-color;
-$legend-border-color:            $gray-light;
+$legend-color:                   $text-color !default;
+$legend-border-color:            $gray-light !default;
 
 //** Background color for textual input addons
-$input-group-addon-bg:           $btn-default-bg;
+$input-group-addon-bg:           $btn-default-bg !default;
 //** Border color for textual input addons
-$input-group-addon-border-color: transparent;
+$input-group-addon-border-color: transparent !default;
 
 //** Disabled cursor for form controls and buttons.
-$cursor-disabled:                not-allowed;
+$cursor-disabled:                not-allowed !default;
 
 
 //== Dropdowns
@@ -227,34 +227,34 @@ $cursor-disabled:                not-allowed;
 //## Dropdown menu container and contents.
 
 //** Background for the dropdown menu.
-$dropdown-bg:                    $gray-light;
+$dropdown-bg:                    $gray-light !default;
 //** Dropdown menu `border-color`.
-$dropdown-border:                transparent;
+$dropdown-border:                transparent !default;
 //** Dropdown menu `border-color` **for IE8**.
-$dropdown-fallback-border:       transparent;
+$dropdown-fallback-border:       transparent !default;
 //** Divider color for between dropdown items.
-$dropdown-divider-bg:            $body-bg;
+$dropdown-divider-bg:            $body-bg !default;
 
 //** Dropdown link text color.
-$dropdown-link-color:            $text-color;
+$dropdown-link-color:            $text-color !default;
 //** Hover color for dropdown links.
-$dropdown-link-hover-color:      $text-color;
+$dropdown-link-hover-color:      $text-color !default;
 //** Hover background for dropdown links.
-$dropdown-link-hover-bg:         darken($gray-light, 3%);
+$dropdown-link-hover-bg:         darken($gray-light, 3%) !default;
 
 //** Active dropdown menu item text color.
-$dropdown-link-active-color:     $component-active-color;
+$dropdown-link-active-color:     $component-active-color !default;
 //** Active dropdown menu item background color.
-$dropdown-link-active-bg:        $component-active-bg;
+$dropdown-link-active-bg:        $component-active-bg !default;
 
 //** Disabled dropdown menu item background color.
-$dropdown-link-disabled-color:   $body-bg;
+$dropdown-link-disabled-color:   $body-bg !default;
 
 //** Text color for headers within dropdown menus.
-$dropdown-header-color:          $body-bg;
+$dropdown-header-color:          $body-bg !default;
 
 //** Deprecated `$dropdown-caret-color` as of v3.1.0
-$dropdown-caret-color:           #000;
+$dropdown-caret-color:           #000 !default;
 
 
 //-- Z-index master list
@@ -264,13 +264,13 @@ $dropdown-caret-color:           #000;
 //
 // Note: These variables are not generated into the Customizer.
 
-$zindex-navbar:            1000;
-$zindex-dropdown:          1000;
-$zindex-popover:           1060;
-$zindex-tooltip:           1070;
-$zindex-navbar-fixed:      1030;
-$zindex-modal-background:  1040;
-$zindex-modal:             1050;
+$zindex-navbar:            1000 !default;
+$zindex-dropdown:          1000 !default;
+$zindex-popover:           1060 !default;
+$zindex-tooltip:           1070 !default;
+$zindex-navbar-fixed:      1030 !default;
+$zindex-modal-background:  1040 !default;
+$zindex-modal:             1050 !default;
 
 
 //== Media queries breakpoints
@@ -279,37 +279,37 @@ $zindex-modal:             1050;
 
 // Extra small screen / phone
 //** Deprecated `$screen-xs` as of v3.0.1
-$screen-xs:                  480px;
+$screen-xs:                  480px !default;
 //** Deprecated `$screen-xs-min` as of v3.2.0
-$screen-xs-min:              $screen-xs;
+$screen-xs-min:              $screen-xs !default;
 //** Deprecated `$screen-phone` as of v3.0.1
-$screen-phone:               $screen-xs-min;
+$screen-phone:               $screen-xs-min !default;
 
 // Small screen / tablet
 //** Deprecated `$screen-sm` as of v3.0.1
-$screen-sm:                  768px;
-$screen-sm-min:              $screen-sm;
+$screen-sm:                  768px !default;
+$screen-sm-min:              $screen-sm !default;
 //** Deprecated `$screen-tablet` as of v3.0.1
-$screen-tablet:              $screen-sm-min;
+$screen-tablet:              $screen-sm-min !default;
 
 // Medium screen / desktop
 //** Deprecated `$screen-md` as of v3.0.1
-$screen-md:                  992px;
-$screen-md-min:              $screen-md;
+$screen-md:                  992px !default;
+$screen-md-min:              $screen-md !default;
 //** Deprecated `$screen-desktop` as of v3.0.1
-$screen-desktop:             $screen-md-min;
+$screen-desktop:             $screen-md-min !default;
 
 // Large screen / wide desktop
 //** Deprecated `$screen-lg` as of v3.0.1
-$screen-lg:                  1200px;
-$screen-lg-min:              $screen-lg;
+$screen-lg:                  1200px !default;
+$screen-lg-min:              $screen-lg !default;
 //** Deprecated `$screen-lg-desktop` as of v3.0.1
-$screen-lg-desktop:          $screen-lg-min;
+$screen-lg-desktop:          $screen-lg-min !default;
 
 // So media queries don't overlap when required, provide a maximum
-$screen-xs-max:              ($screen-sm-min - 1);
-$screen-sm-max:              ($screen-md-min - 1);
-$screen-md-max:              ($screen-lg-min - 1);
+$screen-xs-max:              ($screen-sm-min - 1) !default;
+$screen-sm-max:              ($screen-md-min - 1) !default;
+$screen-md-max:              ($screen-lg-min - 1) !default;
 
 
 //== Grid system
@@ -317,14 +317,14 @@ $screen-md-max:              ($screen-lg-min - 1);
 //## Define your custom responsive grid.
 
 //** Number of columns in the grid.
-$grid-columns:              12;
+$grid-columns:              12 !default;
 //** Padding between columns. Gets divided in half for the left and right.
-$grid-gutter-width:         30px;
+$grid-gutter-width:         30px !default;
 // Navbar collapse
 //** Point at which the navbar becomes uncollapsed.
-$grid-float-breakpoint:     $screen-sm-min;
+$grid-float-breakpoint:     $screen-sm-min !default;
 //** Point at which the navbar begins collapsing.
-$grid-float-breakpoint-max: ($grid-float-breakpoint - 1);
+$grid-float-breakpoint-max: ($grid-float-breakpoint - 1) !default;
 
 
 //== Container sizes
@@ -332,19 +332,19 @@ $grid-float-breakpoint-max: ($grid-float-breakpoint - 1);
 //## Define the maximum width of `.container` for different screen sizes.
 
 // Small screen / tablet
-$container-tablet:             (720px + $grid-gutter-width);
+$container-tablet:             (720px + $grid-gutter-width) !default;
 //** For `$screen-sm-min` and up.
-$container-sm:                 $container-tablet;
+$container-sm:                 $container-tablet !default;
 
 // Medium screen / desktop
-$container-desktop:            (940px + $grid-gutter-width);
+$container-desktop:            (940px + $grid-gutter-width) !default;
 //** For `$screen-md-min` and up.
-$container-md:                 $container-desktop;
+$container-md:                 $container-desktop !default;
 
 // Large screen / wide desktop
-$container-large-desktop:      (1140px + $grid-gutter-width);
+$container-large-desktop:      (1140px + $grid-gutter-width) !default;
 //** For `$screen-lg-min` and up.
-$container-lg:                 $container-large-desktop;
+$container-lg:                 $container-large-desktop !default;
 
 
 //== Navbar
@@ -352,61 +352,61 @@ $container-lg:                 $container-large-desktop;
 //##
 
 // Basics of a navbar
-$navbar-height:                    40px;
-$navbar-margin-bottom:             $line-height-computed;
-$navbar-border-radius:             $border-radius-base;
-$navbar-padding-horizontal:        floor(($grid-gutter-width / 2));
-$navbar-padding-vertical:          (($navbar-height - $line-height-computed) / 2);
-$navbar-collapse-max-height:       340px;
+$navbar-height:                    40px !default;
+$navbar-margin-bottom:             $line-height-computed !default;
+$navbar-border-radius:             $border-radius-base !default;
+$navbar-padding-horizontal:        floor(($grid-gutter-width / 2)) !default;
+$navbar-padding-vertical:          (($navbar-height - $line-height-computed) / 2) !default;
+$navbar-collapse-max-height:       340px !default;
 
-$navbar-default-color:             $text-color;
-$navbar-default-bg:                $gray-light;
-$navbar-default-border:            transparent;
+$navbar-default-color:             $text-color !default;
+$navbar-default-bg:                $gray-light !default;
+$navbar-default-border:            transparent !default;
 
 // Navbar links
-$navbar-default-link-color:                $text-color;
-$navbar-default-link-hover-color:          $navbar-default-link-color;
-$navbar-default-link-hover-bg:             $dropdown-link-hover-bg;
-$navbar-default-link-active-color:         $navbar-default-link-color;
-$navbar-default-link-active-bg:            $dropdown-link-hover-bg;
-$navbar-default-link-disabled-color:       #ccc;
-$navbar-default-link-disabled-bg:          transparent;
+$navbar-default-link-color:                $text-color !default;
+$navbar-default-link-hover-color:          $navbar-default-link-color !default;
+$navbar-default-link-hover-bg:             $dropdown-link-hover-bg !default;
+$navbar-default-link-active-color:         $navbar-default-link-color !default;
+$navbar-default-link-active-bg:            $dropdown-link-hover-bg !default;
+$navbar-default-link-disabled-color:       #ccc !default;
+$navbar-default-link-disabled-bg:          transparent !default;
 
 // Navbar brand label
-$navbar-default-brand-color:               $navbar-default-link-color;
-$navbar-default-brand-hover-color:         $navbar-default-link-color;
-$navbar-default-brand-hover-bg:            transparent;
+$navbar-default-brand-color:               $navbar-default-link-color !default;
+$navbar-default-brand-hover-color:         $navbar-default-link-color !default;
+$navbar-default-brand-hover-bg:            transparent !default;
 
 // Navbar toggle
-$navbar-default-toggle-hover-bg:           $navbar-default-link-hover-bg;
-$navbar-default-toggle-icon-bar-bg:        $text-color;
-$navbar-default-toggle-border-color:       transparent;
+$navbar-default-toggle-hover-bg:           $navbar-default-link-hover-bg !default;
+$navbar-default-toggle-icon-bar-bg:        $text-color !default;
+$navbar-default-toggle-border-color:       transparent !default;
 
 
 // Inverted navbar
 // Reset inverted navbar basics
-$navbar-inverse-color:                      $text-color;
-$navbar-inverse-bg:                         $brand-primary;
-$navbar-inverse-border:                     transparent;
+$navbar-inverse-color:                      $text-color !default;
+$navbar-inverse-bg:                         $brand-primary !default;
+$navbar-inverse-border:                     transparent !default;
 
 // Inverted navbar links
-$navbar-inverse-link-color:                 $text-color;
-$navbar-inverse-link-hover-color:           $navbar-inverse-link-color;
-$navbar-inverse-link-hover-bg:              darken($navbar-inverse-bg, 5%);
-$navbar-inverse-link-active-color:          $navbar-inverse-link-color;
-$navbar-inverse-link-active-bg:             darken($navbar-inverse-bg, 5%);
-$navbar-inverse-link-disabled-color:        #444;
-$navbar-inverse-link-disabled-bg:           transparent;
+$navbar-inverse-link-color:                 $text-color !default;
+$navbar-inverse-link-hover-color:           $navbar-inverse-link-color !default;
+$navbar-inverse-link-hover-bg:              darken($navbar-inverse-bg, 5%) !default;
+$navbar-inverse-link-active-color:          $navbar-inverse-link-color !default;
+$navbar-inverse-link-active-bg:             darken($navbar-inverse-bg, 5%) !default;
+$navbar-inverse-link-disabled-color:        #444 !default;
+$navbar-inverse-link-disabled-bg:           transparent !default;
 
 // Inverted navbar brand label
-$navbar-inverse-brand-color:                $navbar-inverse-link-color;
-$navbar-inverse-brand-hover-color:          $navbar-inverse-link-color;
-$navbar-inverse-brand-hover-bg:             transparent;
+$navbar-inverse-brand-color:                $navbar-inverse-link-color !default;
+$navbar-inverse-brand-hover-color:          $navbar-inverse-link-color !default;
+$navbar-inverse-brand-hover-bg:             transparent !default;
 
 // Inverted navbar toggle
-$navbar-inverse-toggle-hover-bg:            $navbar-inverse-link-hover-bg;
-$navbar-inverse-toggle-icon-bar-bg:         $text-color;
-$navbar-inverse-toggle-border-color:        transparent;
+$navbar-inverse-toggle-hover-bg:            $navbar-inverse-link-hover-bg !default;
+$navbar-inverse-toggle-icon-bar-bg:         $text-color !default;
+$navbar-inverse-toggle-border-color:        transparent !default;
 
 
 //== Navs
@@ -414,97 +414,97 @@ $navbar-inverse-toggle-border-color:        transparent;
 //##
 
 //=== Shared nav styles
-$nav-link-padding:                          10px 15px;
-$nav-link-hover-bg:                         $gray-light;
+$nav-link-padding:                          10px 15px !default;
+$nav-link-hover-bg:                         $gray-light !default;
 
-$nav-disabled-link-color:                   $gray-light;
-$nav-disabled-link-hover-color:             $gray-light;
+$nav-disabled-link-color:                   $gray-light !default;
+$nav-disabled-link-hover-color:             $gray-light !default;
 
 //== Tabs
-$nav-tabs-border-color:                     transparent;
+$nav-tabs-border-color:                     transparent !default;
 
-$nav-tabs-link-hover-border-color:          $gray-light;
+$nav-tabs-link-hover-border-color:          $gray-light !default;
 
-$nav-tabs-active-link-hover-bg:             $body-bg;
-$nav-tabs-active-link-hover-color:          $text-color;
-$nav-tabs-active-link-hover-border-color:   $gray-light;
+$nav-tabs-active-link-hover-bg:             $body-bg !default;
+$nav-tabs-active-link-hover-color:          $text-color !default;
+$nav-tabs-active-link-hover-border-color:   $gray-light !default;
 
-$nav-tabs-justified-link-border-color:            $gray-light;
-$nav-tabs-justified-active-link-border-color:     $gray-light;
+$nav-tabs-justified-link-border-color:            $gray-light !default;
+$nav-tabs-justified-active-link-border-color:     $gray-light !default;
 
 //== Pills
-$nav-pills-border-radius:                   $border-radius-base;
-$nav-pills-active-link-hover-bg:            $component-active-bg;
-$nav-pills-active-link-hover-color:         $component-active-color;
+$nav-pills-border-radius:                   $border-radius-base !default;
+$nav-pills-active-link-hover-bg:            $component-active-bg !default;
+$nav-pills-active-link-hover-color:         $component-active-color !default;
 
 
 //== Pagination
 //
 //##
 
-$pagination-color:                     $text-color;
-$pagination-bg:                        $gray-light;
-$pagination-border:                    transparent;
+$pagination-color:                     $text-color !default;
+$pagination-bg:                        $gray-light !default;
+$pagination-border:                    transparent !default;
 
-$pagination-hover-color:               $text-color;
-$pagination-hover-bg:                  $table-bg-hover;
-$pagination-hover-border:              transparent;
+$pagination-hover-color:               $text-color !default;
+$pagination-hover-bg:                  $table-bg-hover !default;
+$pagination-hover-border:              transparent !default;
 
-$pagination-active-color:              $text-color;
-$pagination-active-bg:                 $brand-primary;
-$pagination-active-border:             transparent;
+$pagination-active-color:              $text-color !default;
+$pagination-active-bg:                 $brand-primary !default;
+$pagination-active-border:             transparent !default;
 
-$pagination-disabled-color:            darken($table-bg-hover, 10%);
-$pagination-disabled-bg:               $gray-light;
-$pagination-disabled-border:           transparent;
+$pagination-disabled-color:            darken($table-bg-hover, 10%) !default;
+$pagination-disabled-bg:               $gray-light !default;
+$pagination-disabled-border:           transparent !default;
 
 
 //== Pager
 //
 //##
 
-$pager-bg:                             $pagination-bg;
-$pager-border:                         $pagination-border;
-$pager-border-radius:                  15px;
+$pager-bg:                             $pagination-bg !default;
+$pager-border:                         $pagination-border !default;
+$pager-border-radius:                  15px !default;
 
-$pager-hover-bg:                       $pagination-hover-bg;
+$pager-hover-bg:                       $pagination-hover-bg !default;
 
-$pager-active-bg:                      $pagination-active-bg;
-$pager-active-color:                   $pagination-active-color;
+$pager-active-bg:                      $pagination-active-bg !default;
+$pager-active-color:                   $pagination-active-color !default;
 
-$pager-disabled-color:                 $pagination-disabled-color;
+$pager-disabled-color:                 $pagination-disabled-color !default;
 
 
 //== Jumbotron
 //
 //##
 
-$jumbotron-padding:              30px;
-$jumbotron-color:                inherit;
-$jumbotron-bg:                   $gray-light;
-$jumbotron-heading-color:        inherit;
-$jumbotron-font-size:            ceil(($font-size-base * 1.5));
+$jumbotron-padding:              30px !default;
+$jumbotron-color:                inherit !default;
+$jumbotron-bg:                   $gray-light !default;
+$jumbotron-heading-color:        inherit !default;
+$jumbotron-font-size:            ceil(($font-size-base * 1.5)) !default;
 
 
 //== Form states and alerts
 //
 //## Define colors for form feedback states and, by default, alerts.
 
-$state-success-text:             $text-color;
-$state-success-bg:               $brand-success;
-$state-success-border:           transparent;
+$state-success-text:             $text-color !default;
+$state-success-bg:               $brand-success !default;
+$state-success-border:           transparent !default;
 
-$state-info-text:                $text-color;
-$state-info-bg:                  $brand-info;
-$state-info-border:              transparent;
+$state-info-text:                $text-color !default;
+$state-info-bg:                  $brand-info !default;
+$state-info-border:              transparent !default;
 
-$state-warning-text:             $text-color;
-$state-warning-bg:               $brand-warning;
-$state-warning-border:           transparent;
+$state-warning-text:             $text-color !default;
+$state-warning-bg:               $brand-warning !default;
+$state-warning-border:           transparent !default;
 
-$state-danger-text:              $text-color;
-$state-danger-bg:                $brand-danger;
-$state-danger-border:            transparent;
+$state-danger-text:              $text-color !default;
+$state-danger-bg:                $brand-danger !default;
+$state-danger-border:            transparent !default;
 
 
 //== Tooltips
@@ -512,17 +512,17 @@ $state-danger-border:            transparent;
 //##
 
 //** Tooltip max width
-$tooltip-max-width:           200px;
+$tooltip-max-width:           200px !default;
 //** Tooltip text color
-$tooltip-color:               #fff;
+$tooltip-color:               #fff !default;
 //** Tooltip background color
-$tooltip-bg:                  #000;
-$tooltip-opacity:             .9;
+$tooltip-bg:                  #000 !default;
+$tooltip-opacity:             .9 !default;
 
 //** Tooltip arrow width
-$tooltip-arrow-width:         5px;
+$tooltip-arrow-width:         5px !default;
 //** Tooltip arrow color
-$tooltip-arrow-color:         $tooltip-bg;
+$tooltip-arrow-color:         $tooltip-bg !default;
 
 
 //== Popovers
@@ -530,28 +530,28 @@ $tooltip-arrow-color:         $tooltip-bg;
 //##
 
 //** Popover body background color
-$popover-bg:                          $gray-light;
+$popover-bg:                          $gray-light !default;
 //** Popover maximum width
-$popover-max-width:                   276px;
+$popover-max-width:                   276px !default;
 //** Popover border color
-$popover-border-color:                transparent;
+$popover-border-color:                transparent !default;
 //** Popover fallback border color
-$popover-fallback-border-color:       transparent;
+$popover-fallback-border-color:       transparent !default;
 
 //** Popover title background color
-$popover-title-bg:                    $table-bg-hover;
+$popover-title-bg:                    $table-bg-hover !default;
 
 //** Popover arrow width
-$popover-arrow-width:                 10px;
+$popover-arrow-width:                 10px !default;
 //** Popover arrow color
-$popover-arrow-color:                 $popover-bg;
+$popover-arrow-color:                 $popover-bg !default;
 
 //** Popover outer arrow width
-$popover-arrow-outer-width:           ($popover-arrow-width + 1);
+$popover-arrow-outer-width:           ($popover-arrow-width + 1) !default;
 //** Popover outer arrow color
-$popover-arrow-outer-color:           transparent;
+$popover-arrow-outer-color:           transparent !default;
 //** Popover outer arrow fallback color
-$popover-arrow-outer-fallback-color:  transparent;
+$popover-arrow-outer-fallback-color:  transparent !default;
 
 
 //== Labels
@@ -559,22 +559,22 @@ $popover-arrow-outer-fallback-color:  transparent;
 //##
 
 //** Default label background color
-$label-default-bg:            $gray-light;
+$label-default-bg:            $gray-light !default;
 //** Primary label background color
-$label-primary-bg:            $brand-primary;
+$label-primary-bg:            $brand-primary !default;
 //** Success label background color
-$label-success-bg:            $brand-success;
+$label-success-bg:            $brand-success !default;
 //** Info label background color
-$label-info-bg:               $brand-info;
+$label-info-bg:               $brand-info !default;
 //** Warning label background color
-$label-warning-bg:            $brand-warning;
+$label-warning-bg:            $brand-warning !default;
 //** Danger label background color
-$label-danger-bg:             $brand-danger;
+$label-danger-bg:             $brand-danger !default;
 
 //** Default label text color
-$label-color:                 #fff;
+$label-color:                 #fff !default;
 //** Default text color of a linked label
-$label-link-hover-color:      #fff;
+$label-link-hover-color:      #fff !default;
 
 
 //== Modals
@@ -582,57 +582,57 @@ $label-link-hover-color:      #fff;
 //##
 
 //** Padding applied to the modal body
-$modal-inner-padding:         20px;
+$modal-inner-padding:         20px !default;
 
 //** Padding applied to the modal title
-$modal-title-padding:         15px;
+$modal-title-padding:         15px !default;
 //** Modal title line-height
-$modal-title-line-height:     $line-height-base;
+$modal-title-line-height:     $line-height-base !default;
 
 //** Background color of modal content area
-$modal-content-bg:                             $gray-light;
+$modal-content-bg:                             $gray-light !default;
 //** Modal content border color
-$modal-content-border-color:                   transparent;
+$modal-content-border-color:                   transparent !default;
 //** Modal content border color **for IE8**
-$modal-content-fallback-border-color:          transparent;
+$modal-content-fallback-border-color:          transparent !default;
 
 //** Modal backdrop background color
-$modal-backdrop-bg:           #000;
+$modal-backdrop-bg:           #000 !default;
 //** Modal backdrop opacity
-$modal-backdrop-opacity:      .5;
+$modal-backdrop-opacity:      .5 !default;
 //** Modal header border color
-$modal-header-border-color:   $body-bg;
+$modal-header-border-color:   $body-bg !default;
 //** Modal footer border color
-$modal-footer-border-color:   $modal-header-border-color;
+$modal-footer-border-color:   $modal-header-border-color !default;
 
-$modal-lg:                    900px;
-$modal-md:                    600px;
-$modal-sm:                    300px;
+$modal-lg:                    900px !default;
+$modal-md:                    600px !default;
+$modal-sm:                    300px !default;
 
 
 //== Alerts
 //
 //## Define alert colors, border radius, and padding.
 
-$alert-padding:               15px;
-$alert-border-radius:         $border-radius-base;
-$alert-link-font-weight:      bold;
+$alert-padding:               15px !default;
+$alert-border-radius:         $border-radius-base !default;
+$alert-link-font-weight:      bold !default;
 
-$alert-success-bg:            $state-success-bg;
-$alert-success-text:          $state-success-text;
-$alert-success-border:        $state-success-border;
+$alert-success-bg:            $state-success-bg !default;
+$alert-success-text:          $state-success-text !default;
+$alert-success-border:        $state-success-border !default;
 
-$alert-info-bg:               $state-info-bg;
-$alert-info-text:             $state-info-text;
-$alert-info-border:           $state-info-border;
+$alert-info-bg:               $state-info-bg !default;
+$alert-info-text:             $state-info-text !default;
+$alert-info-border:           $state-info-border !default;
 
-$alert-warning-bg:            $state-warning-bg;
-$alert-warning-text:          $state-warning-text;
-$alert-warning-border:        $state-warning-border;
+$alert-warning-bg:            $state-warning-bg !default;
+$alert-warning-text:          $state-warning-text !default;
+$alert-warning-border:        $state-warning-border !default;
 
-$alert-danger-bg:             $state-danger-bg;
-$alert-danger-text:           $state-danger-text;
-$alert-danger-border:         $state-danger-border;
+$alert-danger-bg:             $state-danger-bg !default;
+$alert-danger-text:           $state-danger-text !default;
+$alert-danger-border:         $state-danger-border !default;
 
 
 //== Progress bars
@@ -640,22 +640,22 @@ $alert-danger-border:         $state-danger-border;
 //##
 
 //** Background color of the whole progress component
-$progress-bg:                 $gray-light;
+$progress-bg:                 $gray-light !default;
 //** Progress bar text color
-$progress-bar-color:          #fff;
+$progress-bar-color:          #fff !default;
 //** Variable for setting rounded corners on progress bar.
-$progress-border-radius:      $border-radius-base;
+$progress-border-radius:      $border-radius-base !default;
 
 //** Default progress bar color
-$progress-bar-bg:             $brand-primary;
+$progress-bar-bg:             $brand-primary !default;
 //** Success progress bar color
-$progress-bar-success-bg:     $brand-success;
+$progress-bar-success-bg:     $brand-success !default;
 //** Warning progress bar color
-$progress-bar-warning-bg:     $brand-warning;
+$progress-bar-warning-bg:     $brand-warning !default;
 //** Danger progress bar color
-$progress-bar-danger-bg:      $brand-danger;
+$progress-bar-danger-bg:      $brand-danger !default;
 //** Info progress bar color
-$progress-bar-info-bg:        $brand-info;
+$progress-bar-info-bg:        $brand-info !default;
 
 
 //== List group
@@ -663,72 +663,72 @@ $progress-bar-info-bg:        $brand-info;
 //##
 
 //** Background color on `.list-group-item`
-$list-group-bg:                 $gray-light;
+$list-group-bg:                 $gray-light !default;
 //** `.list-group-item` border color
-$list-group-border:             transparent;
+$list-group-border:             transparent !default;
 //** List group border radius
-$list-group-border-radius:      $border-radius-base;
+$list-group-border-radius:      $border-radius-base !default;
 
 //** Background color of single list items on hover
-$list-group-hover-bg:           $table-bg-hover;
+$list-group-hover-bg:           $table-bg-hover !default;
 //** Text color of active list items
-$list-group-active-color:       $component-active-color;
+$list-group-active-color:       $component-active-color !default;
 //** Background color of active list items
-$list-group-active-bg:          $component-active-bg;
+$list-group-active-bg:          $component-active-bg !default;
 //** Border color of active list elements
-$list-group-active-border:      $list-group-active-bg;
+$list-group-active-border:      $list-group-active-bg !default;
 //** Text color for content within active list items
-$list-group-active-text-color:  lighten($list-group-active-bg, 40%);
+$list-group-active-text-color:  lighten($list-group-active-bg, 40%) !default;
 
 //** Text color of disabled list items
-$list-group-disabled-color:      $gray-light;
+$list-group-disabled-color:      $gray-light !default;
 //** Background color of disabled list items
-$list-group-disabled-bg:         $gray-lighter;
+$list-group-disabled-bg:         $gray-lighter !default;
 //** Text color for content within disabled list items
-$list-group-disabled-text-color: $list-group-disabled-color;
+$list-group-disabled-text-color: $list-group-disabled-color !default;
 
-$list-group-link-color:         $text-color;
-$list-group-link-hover-color:   $list-group-link-color;
-$list-group-link-heading-color: $text-color;
+$list-group-link-color:         $text-color !default;
+$list-group-link-hover-color:   $list-group-link-color !default;
+$list-group-link-heading-color: $text-color !default;
 
 
 //== Panels
 //
 //##
 
-$panel-bg:                    $gray-light;
-$panel-body-padding:          15px;
-$panel-heading-padding:       10px 15px;
-$panel-footer-padding:        $panel-heading-padding;
-$panel-border-radius:         $border-radius-base;
+$panel-bg:                    $gray-light !default;
+$panel-body-padding:          15px !default;
+$panel-heading-padding:       10px 15px !default;
+$panel-footer-padding:        $panel-heading-padding !default;
+$panel-border-radius:         $border-radius-base !default;
 
 //** Border color for elements within panels
-$panel-inner-border:          transparent;
-$panel-footer-bg:             $table-bg-hover;
+$panel-inner-border:          transparent !default;
+$panel-footer-bg:             $table-bg-hover !default;
 
-$panel-default-text:          $gray-dark;
-$panel-default-border:        transparent;
-$panel-default-heading-bg:    #f5f5f5;
+$panel-default-text:          $gray-dark !default;
+$panel-default-border:        transparent !default;
+$panel-default-heading-bg:    #f5f5f5 !default;
 
-$panel-primary-text:          #fff;
-$panel-primary-border:        transparent;
-$panel-primary-heading-bg:    $brand-primary;
+$panel-primary-text:          #fff !default;
+$panel-primary-border:        transparent !default;
+$panel-primary-heading-bg:    $brand-primary !default;
 
-$panel-success-text:          $state-success-text;
-$panel-success-border:        transparent;
-$panel-success-heading-bg:    $state-success-bg;
+$panel-success-text:          $state-success-text !default;
+$panel-success-border:        transparent !default;
+$panel-success-heading-bg:    $state-success-bg !default;
 
-$panel-info-text:             $state-info-text;
-$panel-info-border:           transparent;
-$panel-info-heading-bg:       $state-info-bg;
+$panel-info-text:             $state-info-text !default;
+$panel-info-border:           transparent !default;
+$panel-info-heading-bg:       $state-info-bg !default;
 
-$panel-warning-text:          $state-warning-text;
-$panel-warning-border:        transparent;
-$panel-warning-heading-bg:    $state-warning-bg;
+$panel-warning-text:          $state-warning-text !default;
+$panel-warning-border:        transparent !default;
+$panel-warning-heading-bg:    $state-warning-bg !default;
 
-$panel-danger-text:           $state-danger-text;
-$panel-danger-border:         transparent;
-$panel-danger-heading-bg:     $state-danger-bg;
+$panel-danger-text:           $state-danger-text !default;
+$panel-danger-border:         transparent !default;
+$panel-danger-heading-bg:     $state-danger-bg !default;
 
 
 //== Thumbnails
@@ -736,103 +736,103 @@ $panel-danger-heading-bg:     $state-danger-bg;
 //##
 
 //** Padding around the thumbnail image
-$thumbnail-padding:           4px;
+$thumbnail-padding:           4px !default;
 //** Thumbnail background color
-$thumbnail-bg:                $body-bg;
+$thumbnail-bg:                $body-bg !default;
 //** Thumbnail border color
-$thumbnail-border:            #ddd;
+$thumbnail-border:            #ddd !default;
 //** Thumbnail border radius
-$thumbnail-border-radius:     $border-radius-base;
+$thumbnail-border-radius:     $border-radius-base !default;
 
 //** Custom text color for thumbnail captions
-$thumbnail-caption-color:     $text-color;
+$thumbnail-caption-color:     $text-color !default;
 //** Padding around the thumbnail caption
-$thumbnail-caption-padding:   9px;
+$thumbnail-caption-padding:   9px !default;
 
 
 //== Wells
 //
 //## 
 
-$well-bg:                     $gray-light;
-$well-border:                 transparent;
+$well-bg:                     $gray-light !default;
+$well-border:                 transparent !default;
 
 
 //== Badges
 //
 //##
 
-$badge-color:                 $text-color;
+$badge-color:                 $text-color !default;
 //** Linked badge text color on hover
-$badge-link-hover-color:      #fff;
-$badge-bg:                    $gray-light;
+$badge-link-hover-color:      #fff !default;
+$badge-bg:                    $gray-light !default;
 
 //** Badge text color in active nav link
-$badge-active-color:          $link-color;
+$badge-active-color:          $link-color !default;
 //** Badge background color in active nav link
-$badge-active-bg:             #fff;
+$badge-active-bg:             #fff !default;
 
-$badge-font-weight:           300;
-$badge-line-height:           1;
-$badge-border-radius:         10px;
+$badge-font-weight:           300 !default;
+$badge-line-height:           1 !default;
+$badge-border-radius:         10px !default;
 
 
 //== Breadcrumbs
 //
 //##
 
-$breadcrumb-padding-vertical:   8px;
-$breadcrumb-padding-horizontal: 15px;
+$breadcrumb-padding-vertical:   8px !default;
+$breadcrumb-padding-horizontal: 15px !default;
 //** Breadcrumb background color
-$breadcrumb-bg:                 $gray-light;
+$breadcrumb-bg:                 $gray-light !default;
 //** Breadcrumb text color
-$breadcrumb-color:              $text-color;
+$breadcrumb-color:              $text-color !default;
 //** Text color of current page in the breadcrumb
-$breadcrumb-active-color:       $text-color;
+$breadcrumb-active-color:       $text-color !default;
 //** Textual separator for between breadcrumb elements
-$breadcrumb-separator:          "/";
+$breadcrumb-separator:          "/" !default;
 
 
 //== Carousel
 //
 //##
 
-$carousel-text-shadow:                        0 1px 2px rgba(0,0,0,.6);
+$carousel-text-shadow:                        0 1px 2px rgba(0,0,0,.6) !default;
 
-$carousel-control-color:                      #fff;
-$carousel-control-width:                      15%;
-$carousel-control-opacity:                    .5;
-$carousel-control-font-size:                  20px;
+$carousel-control-color:                      #fff !default;
+$carousel-control-width:                      15% !default;
+$carousel-control-opacity:                    .5 !default;
+$carousel-control-font-size:                  20px !default;
 
-$carousel-indicator-active-bg:                #fff;
-$carousel-indicator-border-color:             #fff;
+$carousel-indicator-active-bg:                #fff !default;
+$carousel-indicator-border-color:             #fff !default;
 
-$carousel-caption-color:                      #fff;
+$carousel-caption-color:                      #fff !default;
 
 
 //== Close
 //
 //##
 
-$close-font-weight:           bold;
-$close-color:                 $text-color;
-$close-text-shadow:           none;
+$close-font-weight:           bold !default;
+$close-color:                 $text-color !default;
+$close-text-shadow:           none !default;
 
 
 //== Code
 //
 //##
 
-$code-color:                  #c7254e;
-$code-bg:                     #f9f2f4;
+$code-color:                  #c7254e !default;
+$code-bg:                     #f9f2f4 !default;
 
-$kbd-color:                   #fff;
-$kbd-bg:                      #333;
+$kbd-color:                   #fff !default;
+$kbd-bg:                      #333 !default;
 
-$pre-bg:                      #f5f5f5;
-$pre-color:                   $gray-dark;
-$pre-border-color:            #ccc;
-$pre-scrollable-max-height:   340px;
+$pre-bg:                      #f5f5f5 !default;
+$pre-color:                   $gray-dark !default;
+$pre-border-color:            #ccc !default;
+$pre-scrollable-max-height:   340px !default;
 
 
 //== Type
@@ -840,22 +840,22 @@ $pre-scrollable-max-height:   340px;
 //##
 
 //** Horizontal offset for forms and lists.
-$component-offset-horizontal: 180px;
+$component-offset-horizontal: 180px !default;
 //** Text muted color
-$text-muted:                  $gray-light;
+$text-muted:                  $gray-light !default;
 //** Abbreviations and acronyms border color
-$abbr-border-color:           $gray-light;
+$abbr-border-color:           $gray-light !default;
 //** Headings small color
-$headings-small-color:        $text-color;
+$headings-small-color:        $text-color !default;
 //** Blockquote small color
-$blockquote-small-color:      $text-color;
+$blockquote-small-color:      $text-color !default;
 //** Blockquote font size
-$blockquote-font-size:        ($font-size-base * 1.25);
+$blockquote-font-size:        ($font-size-base * 1.25) !default;
 //** Blockquote border color
-$blockquote-border-color:     $gray-light;
+$blockquote-border-color:     $gray-light !default;
 //** Page header border color
-$page-header-border-color:    $gray-lighter;
+$page-header-border-color:    $gray-lighter !default;
 //** Width of horizontal description list titles
-$dl-horizontal-offset:        $component-offset-horizontal;
+$dl-horizontal-offset:        $component-offset-horizontal !default;
 //** Horizontal line color.
-$hr-border:                   lighten($gray-light, 5%);
+$hr-border:                   lighten($gray-light, 5%) !default;
diff --git a/united/_variables.scss b/united/_variables.scss
index 2e9a8cf0..1b3d8888 100644
--- a/united/_variables.scss
+++ b/united/_variables.scss
@@ -7,18 +7,18 @@
 //
 //## Gray and brand colors for use across Bootstrap.
 
-$gray-base:              #000;
-$gray-darker:            lighten($gray-base, 13.5%); // #222
-$gray-dark:              #333;   // #333
-$gray:                   #777; // #555
-$gray-light:             #AEA79F;   // #999
-$gray-lighter:           lighten($gray-base, 93.5%); // #eee
+$gray-base:              #000 !default;
+$gray-darker:            lighten($gray-base, 13.5%) !default; // #222
+$gray-dark:              #333 !default;   // #333
+$gray:                   #777 !default; // #555
+$gray-light:             #AEA79F !default;   // #999
+$gray-lighter:           lighten($gray-base, 93.5%) !default; // #eee
 
-$brand-primary:         #DD4814;
-$brand-success:         #38B44A;
-$brand-info:            #772953;
-$brand-warning:         #EFB73E;
-$brand-danger:          #DF382C;
+$brand-primary:         #DD4814 !default;
+$brand-success:         #38B44A !default;
+$brand-info:            #772953 !default;
+$brand-warning:         #EFB73E !default;
+$brand-danger:          #DF382C !default;
 
 
 //== Scaffolding
@@ -26,49 +26,49 @@ $brand-danger:          #DF382C;
 //## Settings for some of the most global styles.
 
 //** Background color for ``.
-$body-bg:               #fff;
+$body-bg:               #fff !default;
 //** Global text color on ``.
-$text-color:            $gray-dark;
+$text-color:            $gray-dark !default;
 
 //** Global textual link color.
-$link-color:            $brand-primary;
+$link-color:            $brand-primary !default;
 //** Link hover color set via `darken()` function.
-$link-hover-color:      darken($link-color, 15%);
+$link-hover-color:      darken($link-color, 15%) !default;
 //** Link hover decoration.
-$link-hover-decoration: underline;
+$link-hover-decoration: underline !default;
 
 
 //== Typography
 //
 //## Font, line-height, and color for body text, headings, and more.
 
-$font-family-sans-serif:  "Ubuntu", Tahoma, "Helvetica Neue", Helvetica, Arial, sans-serif;
-$font-family-serif:       Georgia, "Times New Roman", Times, serif;
+$font-family-sans-serif:  "Ubuntu", Tahoma, "Helvetica Neue", Helvetica, Arial, sans-serif !default;
+$font-family-serif:       Georgia, "Times New Roman", Times, serif !default;
 //** Default monospace fonts for ``, ``, and `
`.
-$font-family-monospace:   Menlo, Monaco, Consolas, "Courier New", monospace;
-$font-family-base:        $font-family-sans-serif;
+$font-family-monospace:   Menlo, Monaco, Consolas, "Courier New", monospace !default;
+$font-family-base:        $font-family-sans-serif !default;
 
-$font-size-base:          14px;
-$font-size-large:         ceil(($font-size-base * 1.25)); // ~18px
-$font-size-small:         ceil(($font-size-base * 0.85)); // ~12px
+$font-size-base:          14px !default;
+$font-size-large:         ceil(($font-size-base * 1.25)) !default; // ~18px
+$font-size-small:         ceil(($font-size-base * 0.85)) !default; // ~12px
 
-$font-size-h1:            floor(($font-size-base * 2.6)); // ~36px
-$font-size-h2:            floor(($font-size-base * 2.15)); // ~30px
-$font-size-h3:            ceil(($font-size-base * 1.7)); // ~24px
-$font-size-h4:            ceil(($font-size-base * 1.25)); // ~18px
-$font-size-h5:            $font-size-base;
-$font-size-h6:            ceil(($font-size-base * 0.85)); // ~12px
+$font-size-h1:            floor(($font-size-base * 2.6)) !default; // ~36px
+$font-size-h2:            floor(($font-size-base * 2.15)) !default; // ~30px
+$font-size-h3:            ceil(($font-size-base * 1.7)) !default; // ~24px
+$font-size-h4:            ceil(($font-size-base * 1.25)) !default; // ~18px
+$font-size-h5:            $font-size-base !default;
+$font-size-h6:            ceil(($font-size-base * 0.85)) !default; // ~12px
 
 //** Unit-less `line-height` for use in components like buttons.
-$line-height-base:        1.428571429; // 20/14
+$line-height-base:        1.428571429 !default; // 20/14
 //** Computed "line-height" (`font-size` * `line-height`) for use with `margin`, `padding`, etc.
-$line-height-computed:    floor(($font-size-base * $line-height-base)); // ~20px
+$line-height-computed:    floor(($font-size-base * $line-height-base)) !default; // ~20px
 
 //** By default, this inherits from the ``.
-$headings-font-family:    $font-family-base;
-$headings-font-weight:    500;
-$headings-line-height:    1.1;
-$headings-color:          inherit;
+$headings-font-family:    $font-family-base !default;
+$headings-font-weight:    500 !default;
+$headings-line-height:    1.1 !default;
+$headings-color:          inherit !default;
 
 
 //== Iconography
@@ -76,45 +76,45 @@ $headings-color:          inherit;
 //## Specify custom location and filename of the included Glyphicons icon font. Useful for those including Bootstrap via Bower.
 
 //** Load fonts from this directory.
-$icon-font-path:          "../fonts/";
+$icon-font-path:          "../fonts/" !default;
 //** File name for all font files.
-$icon-font-name:          "glyphicons-halflings-regular";
+$icon-font-name:          "glyphicons-halflings-regular" !default;
 //** Element ID within SVG icon file.
-$icon-font-svg-id:        "glyphicons_halflingsregular";
+$icon-font-svg-id:        "glyphicons_halflingsregular" !default;
 
 
 //== Components
 //
 //## Define common padding and border radius sizes and more. Values based on 14px text and 1.428 line-height (~20px to start).
 
-$padding-base-vertical:     8px;
-$padding-base-horizontal:   12px;
+$padding-base-vertical:     8px !default;
+$padding-base-horizontal:   12px !default;
 
-$padding-large-vertical:    14px;
-$padding-large-horizontal:  16px;
+$padding-large-vertical:    14px !default;
+$padding-large-horizontal:  16px !default;
 
-$padding-small-vertical:    5px;
-$padding-small-horizontal:  10px;
+$padding-small-vertical:    5px !default;
+$padding-small-horizontal:  10px !default;
 
-$padding-xs-vertical:       1px;
-$padding-xs-horizontal:     5px;
+$padding-xs-vertical:       1px !default;
+$padding-xs-horizontal:     5px !default;
 
-$line-height-large:         1.3333333; // extra decimals for Win 8.1 Chrome
-$line-height-small:         1.5;
+$line-height-large:         1.3333333 !default; // extra decimals for Win 8.1 Chrome
+$line-height-small:         1.5 !default;
 
-$border-radius-base:        4px;
-$border-radius-large:       6px;
-$border-radius-small:       3px;
+$border-radius-base:        4px !default;
+$border-radius-large:       6px !default;
+$border-radius-small:       3px !default;
 
 //** Global color for active items (e.g., navs or dropdowns).
-$component-active-color:    #fff;
+$component-active-color:    #fff !default;
 //** Global background color for active items (e.g., navs or dropdowns).
-$component-active-bg:       $brand-primary;
+$component-active-bg:       $brand-primary !default;
 
 //** Width of the `border` for generating carets that indicator dropdowns.
-$caret-width-base:          4px;
+$caret-width-base:          4px !default;
 //** Carets increase slightly in size for larger components.
-$caret-width-large:         5px;
+$caret-width-large:         5px !default;
 
 
 //== Tables
@@ -122,53 +122,53 @@ $caret-width-large:         5px;
 //## Customizes the `.table` component with basic values, each used across all table variations.
 
 //** Padding for ``s and ``s.
-$table-cell-padding:            8px;
+$table-cell-padding:            8px !default;
 //** Padding for cells in `.table-condensed`.
-$table-condensed-cell-padding:  5px;
+$table-condensed-cell-padding:  5px !default;
 
 //** Default background color used for all tables.
-$table-bg:                      transparent;
+$table-bg:                      transparent !default;
 //** Background color used for `.table-striped`.
-$table-bg-accent:               #f9f9f9;
+$table-bg-accent:               #f9f9f9 !default;
 //** Background color used for `.table-hover`.
-$table-bg-hover:                #f5f5f5;
-$table-bg-active:               $table-bg-hover;
+$table-bg-hover:                #f5f5f5 !default;
+$table-bg-active:               $table-bg-hover !default;
 
 //** Border color for table and cell borders.
-$table-border-color:            #ddd;
+$table-border-color:            #ddd !default;
 
 
 //== Buttons
 //
 //## For each of Bootstrap's buttons, define text, background and border color.
 
-$btn-font-weight:                normal;
+$btn-font-weight:                normal !default;
 
-$btn-default-color:              #fff;
-$btn-default-bg:                 $gray-light;
-$btn-default-border:             $btn-default-bg;
+$btn-default-color:              #fff !default;
+$btn-default-bg:                 $gray-light !default;
+$btn-default-border:             $btn-default-bg !default;
 
-$btn-primary-color:              $btn-default-color;
-$btn-primary-bg:                 $brand-primary;
-$btn-primary-border:             $btn-primary-bg;
+$btn-primary-color:              $btn-default-color !default;
+$btn-primary-bg:                 $brand-primary !default;
+$btn-primary-border:             $btn-primary-bg !default;
 
-$btn-success-color:              $btn-default-color;
-$btn-success-bg:                 $brand-success;
-$btn-success-border:             $btn-success-bg;
+$btn-success-color:              $btn-default-color !default;
+$btn-success-bg:                 $brand-success !default;
+$btn-success-border:             $btn-success-bg !default;
 
-$btn-info-color:                 $btn-default-color;
-$btn-info-bg:                    $brand-info;
-$btn-info-border:                $btn-info-bg;
+$btn-info-color:                 $btn-default-color !default;
+$btn-info-bg:                    $brand-info !default;
+$btn-info-border:                $btn-info-bg !default;
 
-$btn-warning-color:              $btn-default-color;
-$btn-warning-bg:                 $brand-warning;
-$btn-warning-border:             $btn-warning-bg;
+$btn-warning-color:              $btn-default-color !default;
+$btn-warning-bg:                 $brand-warning !default;
+$btn-warning-border:             $btn-warning-bg !default;
 
-$btn-danger-color:               $btn-default-color;
-$btn-danger-bg:                  $brand-danger;
-$btn-danger-border:              $btn-danger-bg;
+$btn-danger-color:               $btn-default-color !default;
+$btn-danger-bg:                  $brand-danger !default;
+$btn-danger-border:              $btn-danger-bg !default;
 
-$btn-link-disabled-color:        $gray-light;
+$btn-link-disabled-color:        $gray-light !default;
 
 
 //== Forms
@@ -176,50 +176,50 @@ $btn-link-disabled-color:        $gray-light;
 //##
 
 //** `` background color
-$input-bg:                       #fff;
+$input-bg:                       #fff !default;
 //** `` background color
-$input-bg-disabled:              $gray-lighter;
+$input-bg-disabled:              $gray-lighter !default;
 
 //** Text color for ``s
-$input-color:                    $text-color;
+$input-color:                    $text-color !default;
 //** `` border color
-$input-border:                   #ccc;
+$input-border:                   #ccc !default;
 
 // TODO: Rename `$input-border-radius` to `$input-border-radius-base` in v4
 //** Default `.form-control` border radius
 // This has no effect on ``s in CSS.
-$input-border-radius:            $border-radius-base;
+$input-border-radius:            $border-radius-base !default;
 //** Large `.form-control` border radius
-$input-border-radius-large:      $border-radius-large;
+$input-border-radius-large:      $border-radius-large !default;
 //** Small `.form-control` border radius
-$input-border-radius-small:      $border-radius-small;
+$input-border-radius-small:      $border-radius-small !default;
 
 //** Border color for inputs on focus
-$input-border-focus:             #66afe9;
+$input-border-focus:             #66afe9 !default;
 
 //** Placeholder text color
-$input-color-placeholder:        $gray-light;
+$input-color-placeholder:        $gray-light !default;
 
 //** Default `.form-control` height
-$input-height-base:              ($line-height-computed + ($padding-base-vertical * 2) + 2);
+$input-height-base:              ($line-height-computed + ($padding-base-vertical * 2) + 2) !default;
 //** Large `.form-control` height
-$input-height-large:             (ceil($font-size-large * $line-height-large) + ($padding-large-vertical * 2) + 2);
+$input-height-large:             (ceil($font-size-large * $line-height-large) + ($padding-large-vertical * 2) + 2) !default;
 //** Small `.form-control` height
-$input-height-small:             (floor($font-size-small * $line-height-small) + ($padding-small-vertical * 2) + 2);
+$input-height-small:             (floor($font-size-small * $line-height-small) + ($padding-small-vertical * 2) + 2) !default;
 
 //** `.form-group` margin
-$form-group-margin-bottom:       15px;
+$form-group-margin-bottom:       15px !default;
 
-$legend-color:                   $text-color;
-$legend-border-color:            #e5e5e5;
+$legend-color:                   $text-color !default;
+$legend-border-color:            #e5e5e5 !default;
 
 //** Background color for textual input addons
-$input-group-addon-bg:           $gray-lighter;
+$input-group-addon-bg:           $gray-lighter !default;
 //** Border color for textual input addons
-$input-group-addon-border-color: $input-border;
+$input-group-addon-border-color: $input-border !default;
 
 //** Disabled cursor for form controls and buttons.
-$cursor-disabled:                not-allowed;
+$cursor-disabled:                not-allowed !default;
 
 
 //== Dropdowns
@@ -227,34 +227,34 @@ $cursor-disabled:                not-allowed;
 //## Dropdown menu container and contents.
 
 //** Background for the dropdown menu.
-$dropdown-bg:                    #fff;
+$dropdown-bg:                    #fff !default;
 //** Dropdown menu `border-color`.
-$dropdown-border:                rgba(0,0,0,.15);
+$dropdown-border:                rgba(0,0,0,.15) !default;
 //** Dropdown menu `border-color` **for IE8**.
-$dropdown-fallback-border:       #ccc;
+$dropdown-fallback-border:       #ccc !default;
 //** Divider color for between dropdown items.
-$dropdown-divider-bg:            #e5e5e5;
+$dropdown-divider-bg:            #e5e5e5 !default;
 
 //** Dropdown link text color.
-$dropdown-link-color:            $gray-dark;
+$dropdown-link-color:            $gray-dark !default;
 //** Hover color for dropdown links.
-$dropdown-link-hover-color:      #fff;
+$dropdown-link-hover-color:      #fff !default;
 //** Hover background for dropdown links.
-$dropdown-link-hover-bg:         $component-active-bg;
+$dropdown-link-hover-bg:         $component-active-bg !default;
 
 //** Active dropdown menu item text color.
-$dropdown-link-active-color:     #fff;
+$dropdown-link-active-color:     #fff !default;
 //** Active dropdown menu item background color.
-$dropdown-link-active-bg:        $component-active-bg;
+$dropdown-link-active-bg:        $component-active-bg !default;
 
 //** Disabled dropdown menu item background color.
-$dropdown-link-disabled-color:   $gray-light;
+$dropdown-link-disabled-color:   $gray-light !default;
 
 //** Text color for headers within dropdown menus.
-$dropdown-header-color:          $gray-light;
+$dropdown-header-color:          $gray-light !default;
 
 //** Deprecated `$dropdown-caret-color` as of v3.1.0
-$dropdown-caret-color:           #000;
+$dropdown-caret-color:           #000 !default;
 
 
 //-- Z-index master list
@@ -264,13 +264,13 @@ $dropdown-caret-color:           #000;
 //
 // Note: These variables are not generated into the Customizer.
 
-$zindex-navbar:            1000;
-$zindex-dropdown:          1000;
-$zindex-popover:           1060;
-$zindex-tooltip:           1070;
-$zindex-navbar-fixed:      1030;
-$zindex-modal-background:  1040;
-$zindex-modal:             1050;
+$zindex-navbar:            1000 !default;
+$zindex-dropdown:          1000 !default;
+$zindex-popover:           1060 !default;
+$zindex-tooltip:           1070 !default;
+$zindex-navbar-fixed:      1030 !default;
+$zindex-modal-background:  1040 !default;
+$zindex-modal:             1050 !default;
 
 
 //== Media queries breakpoints
@@ -279,37 +279,37 @@ $zindex-modal:             1050;
 
 // Extra small screen / phone
 //** Deprecated `$screen-xs` as of v3.0.1
-$screen-xs:                  480px;
+$screen-xs:                  480px !default;
 //** Deprecated `$screen-xs-min` as of v3.2.0
-$screen-xs-min:              $screen-xs;
+$screen-xs-min:              $screen-xs !default;
 //** Deprecated `$screen-phone` as of v3.0.1
-$screen-phone:               $screen-xs-min;
+$screen-phone:               $screen-xs-min !default;
 
 // Small screen / tablet
 //** Deprecated `$screen-sm` as of v3.0.1
-$screen-sm:                  768px;
-$screen-sm-min:              $screen-sm;
+$screen-sm:                  768px !default;
+$screen-sm-min:              $screen-sm !default;
 //** Deprecated `$screen-tablet` as of v3.0.1
-$screen-tablet:              $screen-sm-min;
+$screen-tablet:              $screen-sm-min !default;
 
 // Medium screen / desktop
 //** Deprecated `$screen-md` as of v3.0.1
-$screen-md:                  992px;
-$screen-md-min:              $screen-md;
+$screen-md:                  992px !default;
+$screen-md-min:              $screen-md !default;
 //** Deprecated `$screen-desktop` as of v3.0.1
-$screen-desktop:             $screen-md-min;
+$screen-desktop:             $screen-md-min !default;
 
 // Large screen / wide desktop
 //** Deprecated `$screen-lg` as of v3.0.1
-$screen-lg:                  1200px;
-$screen-lg-min:              $screen-lg;
+$screen-lg:                  1200px !default;
+$screen-lg-min:              $screen-lg !default;
 //** Deprecated `$screen-lg-desktop` as of v3.0.1
-$screen-lg-desktop:          $screen-lg-min;
+$screen-lg-desktop:          $screen-lg-min !default;
 
 // So media queries don't overlap when required, provide a maximum
-$screen-xs-max:              ($screen-sm-min - 1);
-$screen-sm-max:              ($screen-md-min - 1);
-$screen-md-max:              ($screen-lg-min - 1);
+$screen-xs-max:              ($screen-sm-min - 1) !default;
+$screen-sm-max:              ($screen-md-min - 1) !default;
+$screen-md-max:              ($screen-lg-min - 1) !default;
 
 
 //== Grid system
@@ -317,14 +317,14 @@ $screen-md-max:              ($screen-lg-min - 1);
 //## Define your custom responsive grid.
 
 //** Number of columns in the grid.
-$grid-columns:              12;
+$grid-columns:              12 !default;
 //** Padding between columns. Gets divided in half for the left and right.
-$grid-gutter-width:         30px;
+$grid-gutter-width:         30px !default;
 // Navbar collapse
 //** Point at which the navbar becomes uncollapsed.
-$grid-float-breakpoint:     $screen-sm-min;
+$grid-float-breakpoint:     $screen-sm-min !default;
 //** Point at which the navbar begins collapsing.
-$grid-float-breakpoint-max: ($grid-float-breakpoint - 1);
+$grid-float-breakpoint-max: ($grid-float-breakpoint - 1) !default;
 
 
 //== Container sizes
@@ -332,19 +332,19 @@ $grid-float-breakpoint-max: ($grid-float-breakpoint - 1);
 //## Define the maximum width of `.container` for different screen sizes.
 
 // Small screen / tablet
-$container-tablet:             (720px + $grid-gutter-width);
+$container-tablet:             (720px + $grid-gutter-width) !default;
 //** For `$screen-sm-min` and up.
-$container-sm:                 $container-tablet;
+$container-sm:                 $container-tablet !default;
 
 // Medium screen / desktop
-$container-desktop:            (940px + $grid-gutter-width);
+$container-desktop:            (940px + $grid-gutter-width) !default;
 //** For `$screen-md-min` and up.
-$container-md:                 $container-desktop;
+$container-md:                 $container-desktop !default;
 
 // Large screen / wide desktop
-$container-large-desktop:      (1140px + $grid-gutter-width);
+$container-large-desktop:      (1140px + $grid-gutter-width) !default;
 //** For `$screen-lg-min` and up.
-$container-lg:                 $container-large-desktop;
+$container-lg:                 $container-large-desktop !default;
 
 
 //== Navbar
@@ -352,61 +352,61 @@ $container-lg:                 $container-large-desktop;
 //##
 
 // Basics of a navbar
-$navbar-height:                    50px;
-$navbar-margin-bottom:             $line-height-computed;
-$navbar-border-radius:             $border-radius-base;
-$navbar-padding-horizontal:        floor(($grid-gutter-width / 2));
-$navbar-padding-vertical:          (($navbar-height - $line-height-computed) / 2);
-$navbar-collapse-max-height:       340px;
+$navbar-height:                    50px !default;
+$navbar-margin-bottom:             $line-height-computed !default;
+$navbar-border-radius:             $border-radius-base !default;
+$navbar-padding-horizontal:        floor(($grid-gutter-width / 2)) !default;
+$navbar-padding-vertical:          (($navbar-height - $line-height-computed) / 2) !default;
+$navbar-collapse-max-height:       340px !default;
 
-$navbar-default-color:             #fff;
-$navbar-default-bg:                $brand-primary;
-$navbar-default-border:            darken($navbar-default-bg, 6.5%);
+$navbar-default-color:             #fff !default;
+$navbar-default-bg:                $brand-primary !default;
+$navbar-default-border:            darken($navbar-default-bg, 6.5%) !default;
 
 // Navbar links
-$navbar-default-link-color:                #fff;
-$navbar-default-link-hover-color:          #fff;
-$navbar-default-link-hover-bg:             darken($navbar-default-bg, 15%);
-$navbar-default-link-active-color:         #fff;
-$navbar-default-link-active-bg:            darken($navbar-default-bg, 10%);
-$navbar-default-link-disabled-color:       #ccc;
-$navbar-default-link-disabled-bg:          transparent;
+$navbar-default-link-color:                #fff !default;
+$navbar-default-link-hover-color:          #fff !default;
+$navbar-default-link-hover-bg:             darken($navbar-default-bg, 15%) !default;
+$navbar-default-link-active-color:         #fff !default;
+$navbar-default-link-active-bg:            darken($navbar-default-bg, 10%) !default;
+$navbar-default-link-disabled-color:       #ccc !default;
+$navbar-default-link-disabled-bg:          transparent !default;
 
 // Navbar brand label
-$navbar-default-brand-color:               $navbar-default-link-color;
-$navbar-default-brand-hover-color:         #fff;
-$navbar-default-brand-hover-bg:            none;
+$navbar-default-brand-color:               $navbar-default-link-color !default;
+$navbar-default-brand-hover-color:         #fff !default;
+$navbar-default-brand-hover-bg:            none !default;
 
 // Navbar toggle
-$navbar-default-toggle-hover-bg:           darken($navbar-default-bg, 15%);
-$navbar-default-toggle-icon-bar-bg:        #fff;
-$navbar-default-toggle-border-color:       darken($navbar-default-bg, 15%);
+$navbar-default-toggle-hover-bg:           darken($navbar-default-bg, 15%) !default;
+$navbar-default-toggle-icon-bar-bg:        #fff !default;
+$navbar-default-toggle-border-color:       darken($navbar-default-bg, 15%) !default;
 
 
 // Inverted navbar
 // Reset inverted navbar basics
-$navbar-inverse-color:                      #fff;
-$navbar-inverse-bg:                         $brand-info;
-$navbar-inverse-border:                     darken($navbar-inverse-bg, 10%);
+$navbar-inverse-color:                      #fff !default;
+$navbar-inverse-bg:                         $brand-info !default;
+$navbar-inverse-border:                     darken($navbar-inverse-bg, 10%) !default;
 
 // Inverted navbar links
-$navbar-inverse-link-color:                 #fff;
-$navbar-inverse-link-hover-color:           #fff;
-$navbar-inverse-link-hover-bg:              darken($navbar-inverse-bg, 15%);
-$navbar-inverse-link-active-color:          $navbar-inverse-link-hover-color;
-$navbar-inverse-link-active-bg:             darken($navbar-inverse-bg, 10%);
-$navbar-inverse-link-disabled-color:        #ccc;
-$navbar-inverse-link-disabled-bg:           transparent;
+$navbar-inverse-link-color:                 #fff !default;
+$navbar-inverse-link-hover-color:           #fff !default;
+$navbar-inverse-link-hover-bg:              darken($navbar-inverse-bg, 15%) !default;
+$navbar-inverse-link-active-color:          $navbar-inverse-link-hover-color !default;
+$navbar-inverse-link-active-bg:             darken($navbar-inverse-bg, 10%) !default;
+$navbar-inverse-link-disabled-color:        #ccc !default;
+$navbar-inverse-link-disabled-bg:           transparent !default;
 
 // Inverted navbar brand label
-$navbar-inverse-brand-color:                $navbar-inverse-link-color;
-$navbar-inverse-brand-hover-color:          #fff;
-$navbar-inverse-brand-hover-bg:             none;
+$navbar-inverse-brand-color:                $navbar-inverse-link-color !default;
+$navbar-inverse-brand-hover-color:          #fff !default;
+$navbar-inverse-brand-hover-bg:             none !default;
 
 // Inverted navbar toggle
-$navbar-inverse-toggle-hover-bg:            darken($navbar-inverse-bg, 15%);
-$navbar-inverse-toggle-icon-bar-bg:         #fff;
-$navbar-inverse-toggle-border-color:        darken($navbar-inverse-bg, 15%);
+$navbar-inverse-toggle-hover-bg:            darken($navbar-inverse-bg, 15%) !default;
+$navbar-inverse-toggle-icon-bar-bg:         #fff !default;
+$navbar-inverse-toggle-border-color:        darken($navbar-inverse-bg, 15%) !default;
 
 
 //== Navs
@@ -414,97 +414,97 @@ $navbar-inverse-toggle-border-color:        darken($navbar-inverse-bg, 15%);
 //##
 
 //=== Shared nav styles
-$nav-link-padding:                          10px 15px;
-$nav-link-hover-bg:                         $gray-lighter;
+$nav-link-padding:                          10px 15px !default;
+$nav-link-hover-bg:                         $gray-lighter !default;
 
-$nav-disabled-link-color:                   $gray-light;
-$nav-disabled-link-hover-color:             $gray-light;
+$nav-disabled-link-color:                   $gray-light !default;
+$nav-disabled-link-hover-color:             $gray-light !default;
 
 //== Tabs
-$nav-tabs-border-color:                     #ddd;
+$nav-tabs-border-color:                     #ddd !default;
 
-$nav-tabs-link-hover-border-color:          $gray-lighter;
+$nav-tabs-link-hover-border-color:          $gray-lighter !default;
 
-$nav-tabs-active-link-hover-bg:             $body-bg;
-$nav-tabs-active-link-hover-color:          $gray;
-$nav-tabs-active-link-hover-border-color:   #ddd;
+$nav-tabs-active-link-hover-bg:             $body-bg !default;
+$nav-tabs-active-link-hover-color:          $gray !default;
+$nav-tabs-active-link-hover-border-color:   #ddd !default;
 
-$nav-tabs-justified-link-border-color:            #ddd;
-$nav-tabs-justified-active-link-border-color:     $body-bg;
+$nav-tabs-justified-link-border-color:            #ddd !default;
+$nav-tabs-justified-active-link-border-color:     $body-bg !default;
 
 //== Pills
-$nav-pills-border-radius:                   $border-radius-base;
-$nav-pills-active-link-hover-bg:            $component-active-bg;
-$nav-pills-active-link-hover-color:         $component-active-color;
+$nav-pills-border-radius:                   $border-radius-base !default;
+$nav-pills-active-link-hover-bg:            $component-active-bg !default;
+$nav-pills-active-link-hover-color:         $component-active-color !default;
 
 
 //== Pagination
 //
 //##
 
-$pagination-color:                     $link-color;
-$pagination-bg:                        #fff;
-$pagination-border:                    #ddd;
+$pagination-color:                     $link-color !default;
+$pagination-bg:                        #fff !default;
+$pagination-border:                    #ddd !default;
 
-$pagination-hover-color:               $link-hover-color;
-$pagination-hover-bg:                  $gray-lighter;
-$pagination-hover-border:              #ddd;
+$pagination-hover-color:               $link-hover-color !default;
+$pagination-hover-bg:                  $gray-lighter !default;
+$pagination-hover-border:              #ddd !default;
 
-$pagination-active-color:              $gray-light;
-$pagination-active-bg:                 #f5f5f5;
-$pagination-active-border:             #ddd;
+$pagination-active-color:              $gray-light !default;
+$pagination-active-bg:                 #f5f5f5 !default;
+$pagination-active-border:             #ddd !default;
 
-$pagination-disabled-color:            $gray-light;
-$pagination-disabled-bg:               #fff;
-$pagination-disabled-border:           #ddd;
+$pagination-disabled-color:            $gray-light !default;
+$pagination-disabled-bg:               #fff !default;
+$pagination-disabled-border:           #ddd !default;
 
 
 //== Pager
 //
 //##
 
-$pager-bg:                             $pagination-bg;
-$pager-border:                         $pagination-border;
-$pager-border-radius:                  15px;
+$pager-bg:                             $pagination-bg !default;
+$pager-border:                         $pagination-border !default;
+$pager-border-radius:                  15px !default;
 
-$pager-hover-bg:                       $pagination-hover-bg;
+$pager-hover-bg:                       $pagination-hover-bg !default;
 
-$pager-active-bg:                      $pagination-active-bg;
-$pager-active-color:                   $pagination-active-color;
+$pager-active-bg:                      $pagination-active-bg !default;
+$pager-active-color:                   $pagination-active-color !default;
 
-$pager-disabled-color:                 $gray-light;
+$pager-disabled-color:                 $gray-light !default;
 
 
 //== Jumbotron
 //
 //##
 
-$jumbotron-padding:              30px;
-$jumbotron-color:                inherit;
-$jumbotron-bg:                   $gray-lighter;
-$jumbotron-heading-color:        inherit;
-$jumbotron-font-size:            ceil(($font-size-base * 1.5));
+$jumbotron-padding:              30px !default;
+$jumbotron-color:                inherit !default;
+$jumbotron-bg:                   $gray-lighter !default;
+$jumbotron-heading-color:        inherit !default;
+$jumbotron-font-size:            ceil(($font-size-base * 1.5)) !default;
 
 
 //== Form states and alerts
 //
 //## Define colors for form feedback states and, by default, alerts.
 
-$state-success-text:             #468847;
-$state-success-bg:               #dff0d8;
-$state-success-border:           darken(adjust-hue($state-success-bg, -10), 5%);
+$state-success-text:             #468847 !default;
+$state-success-bg:               #dff0d8 !default;
+$state-success-border:           darken(adjust-hue($state-success-bg, -10), 5%) !default;
 
-$state-info-text:                #3a87ad;
-$state-info-bg:                  #d9edf7;
-$state-info-border:              darken(adjust-hue($state-info-bg, -10), 7%);
+$state-info-text:                #3a87ad !default;
+$state-info-bg:                  #d9edf7 !default;
+$state-info-border:              darken(adjust-hue($state-info-bg, -10), 7%) !default;
 
-$state-warning-text:             #c09853;
-$state-warning-bg:               #fcf8e3;
-$state-warning-border:           darken(adjust-hue($state-warning-bg, -10), 3%);
+$state-warning-text:             #c09853 !default;
+$state-warning-bg:               #fcf8e3 !default;
+$state-warning-border:           darken(adjust-hue($state-warning-bg, -10), 3%) !default;
 
-$state-danger-text:              #b94a48;
-$state-danger-bg:                #f2dede;
-$state-danger-border:            darken(adjust-hue($state-danger-bg, -10), 3%);
+$state-danger-text:              #b94a48 !default;
+$state-danger-bg:                #f2dede !default;
+$state-danger-border:            darken(adjust-hue($state-danger-bg, -10), 3%) !default;
 
 
 //== Tooltips
@@ -512,17 +512,17 @@ $state-danger-border:            darken(adjust-hue($state-danger-bg, -10), 3%);
 //##
 
 //** Tooltip max width
-$tooltip-max-width:           200px;
+$tooltip-max-width:           200px !default;
 //** Tooltip text color
-$tooltip-color:               #fff;
+$tooltip-color:               #fff !default;
 //** Tooltip background color
-$tooltip-bg:                  #000;
-$tooltip-opacity:             .9;
+$tooltip-bg:                  #000 !default;
+$tooltip-opacity:             .9 !default;
 
 //** Tooltip arrow width
-$tooltip-arrow-width:         5px;
+$tooltip-arrow-width:         5px !default;
 //** Tooltip arrow color
-$tooltip-arrow-color:         $tooltip-bg;
+$tooltip-arrow-color:         $tooltip-bg !default;
 
 
 //== Popovers
@@ -530,28 +530,28 @@ $tooltip-arrow-color:         $tooltip-bg;
 //##
 
 //** Popover body background color
-$popover-bg:                          #fff;
+$popover-bg:                          #fff !default;
 //** Popover maximum width
-$popover-max-width:                   276px;
+$popover-max-width:                   276px !default;
 //** Popover border color
-$popover-border-color:                rgba(0,0,0,.2);
+$popover-border-color:                rgba(0,0,0,.2) !default;
 //** Popover fallback border color
-$popover-fallback-border-color:       #ccc;
+$popover-fallback-border-color:       #ccc !default;
 
 //** Popover title background color
-$popover-title-bg:                    darken($popover-bg, 3%);
+$popover-title-bg:                    darken($popover-bg, 3%) !default;
 
 //** Popover arrow width
-$popover-arrow-width:                 10px;
+$popover-arrow-width:                 10px !default;
 //** Popover arrow color
-$popover-arrow-color:                 $popover-bg;
+$popover-arrow-color:                 $popover-bg !default;
 
 //** Popover outer arrow width
-$popover-arrow-outer-width:           ($popover-arrow-width + 1);
+$popover-arrow-outer-width:           ($popover-arrow-width + 1) !default;
 //** Popover outer arrow color
-$popover-arrow-outer-color:           fadein($popover-border-color, 5%);
+$popover-arrow-outer-color:           fadein($popover-border-color, 5%) !default;
 //** Popover outer arrow fallback color
-$popover-arrow-outer-fallback-color:  darken($popover-fallback-border-color, 20%);
+$popover-arrow-outer-fallback-color:  darken($popover-fallback-border-color, 20%) !default;
 
 
 //== Labels
@@ -559,22 +559,22 @@ $popover-arrow-outer-fallback-color:  darken($popover-fallback-border-color, 20%
 //##
 
 //** Default label background color
-$label-default-bg:            $btn-default-bg;
+$label-default-bg:            $btn-default-bg !default;
 //** Primary label background color
-$label-primary-bg:            $brand-primary;
+$label-primary-bg:            $brand-primary !default;
 //** Success label background color
-$label-success-bg:            $brand-success;
+$label-success-bg:            $brand-success !default;
 //** Info label background color
-$label-info-bg:               $brand-info;
+$label-info-bg:               $brand-info !default;
 //** Warning label background color
-$label-warning-bg:            $brand-warning;
+$label-warning-bg:            $brand-warning !default;
 //** Danger label background color
-$label-danger-bg:             $brand-danger;
+$label-danger-bg:             $brand-danger !default;
 
 //** Default label text color
-$label-color:                 #fff;
+$label-color:                 #fff !default;
 //** Default text color of a linked label
-$label-link-hover-color:      #fff;
+$label-link-hover-color:      #fff !default;
 
 
 //== Modals
@@ -582,57 +582,57 @@ $label-link-hover-color:      #fff;
 //##
 
 //** Padding applied to the modal body
-$modal-inner-padding:         20px;
+$modal-inner-padding:         20px !default;
 
 //** Padding applied to the modal title
-$modal-title-padding:         15px;
+$modal-title-padding:         15px !default;
 //** Modal title line-height
-$modal-title-line-height:     $line-height-base;
+$modal-title-line-height:     $line-height-base !default;
 
 //** Background color of modal content area
-$modal-content-bg:                             #fff;
+$modal-content-bg:                             #fff !default;
 //** Modal content border color
-$modal-content-border-color:                   rgba(0,0,0,.2);
+$modal-content-border-color:                   rgba(0,0,0,.2) !default;
 //** Modal content border color **for IE8**
-$modal-content-fallback-border-color:          #999;
+$modal-content-fallback-border-color:          #999 !default;
 
 //** Modal backdrop background color
-$modal-backdrop-bg:           #000;
+$modal-backdrop-bg:           #000 !default;
 //** Modal backdrop opacity
-$modal-backdrop-opacity:      .5;
+$modal-backdrop-opacity:      .5 !default;
 //** Modal header border color
-$modal-header-border-color:   #e5e5e5;
+$modal-header-border-color:   #e5e5e5 !default;
 //** Modal footer border color
-$modal-footer-border-color:   $modal-header-border-color;
+$modal-footer-border-color:   $modal-header-border-color !default;
 
-$modal-lg:                    900px;
-$modal-md:                    600px;
-$modal-sm:                    300px;
+$modal-lg:                    900px !default;
+$modal-md:                    600px !default;
+$modal-sm:                    300px !default;
 
 
 //== Alerts
 //
 //## Define alert colors, border radius, and padding.
 
-$alert-padding:               15px;
-$alert-border-radius:         $border-radius-base;
-$alert-link-font-weight:      bold;
+$alert-padding:               15px !default;
+$alert-border-radius:         $border-radius-base !default;
+$alert-link-font-weight:      bold !default;
 
-$alert-success-bg:            $state-success-bg;
-$alert-success-text:          $state-success-text;
-$alert-success-border:        $state-success-border;
+$alert-success-bg:            $state-success-bg !default;
+$alert-success-text:          $state-success-text !default;
+$alert-success-border:        $state-success-border !default;
 
-$alert-info-bg:               $state-info-bg;
-$alert-info-text:             $state-info-text;
-$alert-info-border:           $state-info-border;
+$alert-info-bg:               $state-info-bg !default;
+$alert-info-text:             $state-info-text !default;
+$alert-info-border:           $state-info-border !default;
 
-$alert-warning-bg:            $state-warning-bg;
-$alert-warning-text:          $state-warning-text;
-$alert-warning-border:        $state-warning-border;
+$alert-warning-bg:            $state-warning-bg !default;
+$alert-warning-text:          $state-warning-text !default;
+$alert-warning-border:        $state-warning-border !default;
 
-$alert-danger-bg:             $state-danger-bg;
-$alert-danger-text:           $state-danger-text;
-$alert-danger-border:         $state-danger-border;
+$alert-danger-bg:             $state-danger-bg !default;
+$alert-danger-text:           $state-danger-text !default;
+$alert-danger-border:         $state-danger-border !default;
 
 
 //== Progress bars
@@ -640,22 +640,22 @@ $alert-danger-border:         $state-danger-border;
 //##
 
 //** Background color of the whole progress component
-$progress-bg:                 #f5f5f5;
+$progress-bg:                 #f5f5f5 !default;
 //** Progress bar text color
-$progress-bar-color:          #fff;
+$progress-bar-color:          #fff !default;
 //** Variable for setting rounded corners on progress bar.
-$progress-border-radius:      $border-radius-base;
+$progress-border-radius:      $border-radius-base !default;
 
 //** Default progress bar color
-$progress-bar-bg:             $brand-primary;
+$progress-bar-bg:             $brand-primary !default;
 //** Success progress bar color
-$progress-bar-success-bg:     $brand-success;
+$progress-bar-success-bg:     $brand-success !default;
 //** Warning progress bar color
-$progress-bar-warning-bg:     $brand-warning;
+$progress-bar-warning-bg:     $brand-warning !default;
 //** Danger progress bar color
-$progress-bar-danger-bg:      $brand-danger;
+$progress-bar-danger-bg:      $brand-danger !default;
 //** Info progress bar color
-$progress-bar-info-bg:        $brand-info;
+$progress-bar-info-bg:        $brand-info !default;
 
 
 //== List group
@@ -663,72 +663,72 @@ $progress-bar-info-bg:        $brand-info;
 //##
 
 //** Background color on `.list-group-item`
-$list-group-bg:                 #fff;
+$list-group-bg:                 #fff !default;
 //** `.list-group-item` border color
-$list-group-border:             #ddd;
+$list-group-border:             #ddd !default;
 //** List group border radius
-$list-group-border-radius:      $border-radius-base;
+$list-group-border-radius:      $border-radius-base !default;
 
 //** Background color of single list items on hover
-$list-group-hover-bg:           #f5f5f5;
+$list-group-hover-bg:           #f5f5f5 !default;
 //** Text color of active list items
-$list-group-active-color:       $component-active-color;
+$list-group-active-color:       $component-active-color !default;
 //** Background color of active list items
-$list-group-active-bg:          $component-active-bg;
+$list-group-active-bg:          $component-active-bg !default;
 //** Border color of active list elements
-$list-group-active-border:      $list-group-active-bg;
+$list-group-active-border:      $list-group-active-bg !default;
 //** Text color for content within active list items
-$list-group-active-text-color:  lighten($list-group-active-bg, 40%);
+$list-group-active-text-color:  lighten($list-group-active-bg, 40%) !default;
 
 //** Text color of disabled list items
-$list-group-disabled-color:      $gray-light;
+$list-group-disabled-color:      $gray-light !default;
 //** Background color of disabled list items
-$list-group-disabled-bg:         $gray-lighter;
+$list-group-disabled-bg:         $gray-lighter !default;
 //** Text color for content within disabled list items
-$list-group-disabled-text-color: $list-group-disabled-color;
+$list-group-disabled-text-color: $list-group-disabled-color !default;
 
-$list-group-link-color:         #555;
-$list-group-link-hover-color:   $list-group-link-color;
-$list-group-link-heading-color: #333;
+$list-group-link-color:         #555 !default;
+$list-group-link-hover-color:   $list-group-link-color !default;
+$list-group-link-heading-color: #333 !default;
 
 
 //== Panels
 //
 //##
 
-$panel-bg:                    #fff;
-$panel-body-padding:          15px;
-$panel-heading-padding:       10px 15px;
-$panel-footer-padding:        $panel-heading-padding;
-$panel-border-radius:         $border-radius-base;
+$panel-bg:                    #fff !default;
+$panel-body-padding:          15px !default;
+$panel-heading-padding:       10px 15px !default;
+$panel-footer-padding:        $panel-heading-padding !default;
+$panel-border-radius:         $border-radius-base !default;
 
 //** Border color for elements within panels
-$panel-inner-border:          #ddd;
-$panel-footer-bg:             #f5f5f5;
+$panel-inner-border:          #ddd !default;
+$panel-footer-bg:             #f5f5f5 !default;
 
-$panel-default-text:          $gray-dark;
-$panel-default-border:        #ddd;
-$panel-default-heading-bg:    #f5f5f5;
+$panel-default-text:          $gray-dark !default;
+$panel-default-border:        #ddd !default;
+$panel-default-heading-bg:    #f5f5f5 !default;
 
-$panel-primary-text:          #fff;
-$panel-primary-border:        $brand-primary;
-$panel-primary-heading-bg:    $brand-primary;
+$panel-primary-text:          #fff !default;
+$panel-primary-border:        $brand-primary !default;
+$panel-primary-heading-bg:    $brand-primary !default;
 
-$panel-success-text:          $state-success-text;
-$panel-success-border:        $state-success-border;
-$panel-success-heading-bg:    $state-success-bg;
+$panel-success-text:          $state-success-text !default;
+$panel-success-border:        $state-success-border !default;
+$panel-success-heading-bg:    $state-success-bg !default;
 
-$panel-info-text:             $state-info-text;
-$panel-info-border:           $state-info-border;
-$panel-info-heading-bg:       $state-info-bg;
+$panel-info-text:             $state-info-text !default;
+$panel-info-border:           $state-info-border !default;
+$panel-info-heading-bg:       $state-info-bg !default;
 
-$panel-warning-text:          $state-warning-text;
-$panel-warning-border:        $state-warning-border;
-$panel-warning-heading-bg:    $state-warning-bg;
+$panel-warning-text:          $state-warning-text !default;
+$panel-warning-border:        $state-warning-border !default;
+$panel-warning-heading-bg:    $state-warning-bg !default;
 
-$panel-danger-text:           $state-danger-text;
-$panel-danger-border:         $state-danger-border;
-$panel-danger-heading-bg:     $state-danger-bg;
+$panel-danger-text:           $state-danger-text !default;
+$panel-danger-border:         $state-danger-border !default;
+$panel-danger-heading-bg:     $state-danger-bg !default;
 
 
 //== Thumbnails
@@ -736,103 +736,103 @@ $panel-danger-heading-bg:     $state-danger-bg;
 //##
 
 //** Padding around the thumbnail image
-$thumbnail-padding:           4px;
+$thumbnail-padding:           4px !default;
 //** Thumbnail background color
-$thumbnail-bg:                $body-bg;
+$thumbnail-bg:                $body-bg !default;
 //** Thumbnail border color
-$thumbnail-border:            #ddd;
+$thumbnail-border:            #ddd !default;
 //** Thumbnail border radius
-$thumbnail-border-radius:     $border-radius-base;
+$thumbnail-border-radius:     $border-radius-base !default;
 
 //** Custom text color for thumbnail captions
-$thumbnail-caption-color:     $text-color;
+$thumbnail-caption-color:     $text-color !default;
 //** Padding around the thumbnail caption
-$thumbnail-caption-padding:   9px;
+$thumbnail-caption-padding:   9px !default;
 
 
 //== Wells
 //
 //##
 
-$well-bg:                     #f5f5f5;
-$well-border:                 darken($well-bg, 7%);
+$well-bg:                     #f5f5f5 !default;
+$well-border:                 darken($well-bg, 7%) !default;
 
 
 //== Badges
 //
 //##
 
-$badge-color:                 #fff;
+$badge-color:                 #fff !default;
 //** Linked badge text color on hover
-$badge-link-hover-color:      #fff;
-$badge-bg:                    $gray-light;
+$badge-link-hover-color:      #fff !default;
+$badge-bg:                    $gray-light !default;
 
 //** Badge text color in active nav link
-$badge-active-color:          $link-color;
+$badge-active-color:          $link-color !default;
 //** Badge background color in active nav link
-$badge-active-bg:             #fff;
+$badge-active-bg:             #fff !default;
 
-$badge-font-weight:           bold;
-$badge-line-height:           1;
-$badge-border-radius:         10px;
+$badge-font-weight:           bold !default;
+$badge-line-height:           1 !default;
+$badge-border-radius:         10px !default;
 
 
 //== Breadcrumbs
 //
 //##
 
-$breadcrumb-padding-vertical:   8px;
-$breadcrumb-padding-horizontal: 15px;
+$breadcrumb-padding-vertical:   8px !default;
+$breadcrumb-padding-horizontal: 15px !default;
 //** Breadcrumb background color
-$breadcrumb-bg:                 #f5f5f5;
+$breadcrumb-bg:                 #f5f5f5 !default;
 //** Breadcrumb text color
-$breadcrumb-color:              #ccc;
+$breadcrumb-color:              #ccc !default;
 //** Text color of current page in the breadcrumb
-$breadcrumb-active-color:       $gray-light;
+$breadcrumb-active-color:       $gray-light !default;
 //** Textual separator for between breadcrumb elements
-$breadcrumb-separator:          "/";
+$breadcrumb-separator:          "/" !default;
 
 
 //== Carousel
 //
 //##
 
-$carousel-text-shadow:                        0 1px 2px rgba(0,0,0,.6);
+$carousel-text-shadow:                        0 1px 2px rgba(0,0,0,.6) !default;
 
-$carousel-control-color:                      #fff;
-$carousel-control-width:                      15%;
-$carousel-control-opacity:                    .5;
-$carousel-control-font-size:                  20px;
+$carousel-control-color:                      #fff !default;
+$carousel-control-width:                      15% !default;
+$carousel-control-opacity:                    .5 !default;
+$carousel-control-font-size:                  20px !default;
 
-$carousel-indicator-active-bg:                #fff;
-$carousel-indicator-border-color:             #fff;
+$carousel-indicator-active-bg:                #fff !default;
+$carousel-indicator-border-color:             #fff !default;
 
-$carousel-caption-color:                      #fff;
+$carousel-caption-color:                      #fff !default;
 
 
 //== Close
 //
 //##
 
-$close-font-weight:           bold;
-$close-color:                 #000;
-$close-text-shadow:           0 1px 0 #fff;
+$close-font-weight:           bold !default;
+$close-color:                 #000 !default;
+$close-text-shadow:           0 1px 0 #fff !default;
 
 
 //== Code
 //
 //##
 
-$code-color:                  #c7254e;
-$code-bg:                     #f9f2f4;
+$code-color:                  #c7254e !default;
+$code-bg:                     #f9f2f4 !default;
 
-$kbd-color:                   #fff;
-$kbd-bg:                      #333;
+$kbd-color:                   #fff !default;
+$kbd-bg:                      #333 !default;
 
-$pre-bg:                      #f5f5f5;
-$pre-color:                   $gray-dark;
-$pre-border-color:            #ccc;
-$pre-scrollable-max-height:   340px;
+$pre-bg:                      #f5f5f5 !default;
+$pre-color:                   $gray-dark !default;
+$pre-border-color:            #ccc !default;
+$pre-scrollable-max-height:   340px !default;
 
 
 //== Type
@@ -840,22 +840,22 @@ $pre-scrollable-max-height:   340px;
 //##
 
 //** Horizontal offset for forms and lists.
-$component-offset-horizontal: 180px;
+$component-offset-horizontal: 180px !default;
 //** Text muted color
-$text-muted:                  $gray-light;
+$text-muted:                  $gray-light !default;
 //** Abbreviations and acronyms border color
-$abbr-border-color:           $gray-light;
+$abbr-border-color:           $gray-light !default;
 //** Headings small color
-$headings-small-color:        $gray-light;
+$headings-small-color:        $gray-light !default;
 //** Blockquote small color
-$blockquote-small-color:      $gray-light;
+$blockquote-small-color:      $gray-light !default;
 //** Blockquote font size
-$blockquote-font-size:        ($font-size-base * 1.25);
+$blockquote-font-size:        ($font-size-base * 1.25) !default;
 //** Blockquote border color
-$blockquote-border-color:     $gray-lighter;
+$blockquote-border-color:     $gray-lighter !default;
 //** Page header border color
-$page-header-border-color:    $gray-lighter;
+$page-header-border-color:    $gray-lighter !default;
 //** Width of horizontal description list titles
-$dl-horizontal-offset:        $component-offset-horizontal;
+$dl-horizontal-offset:        $component-offset-horizontal !default;
 //** Horizontal line color.
-$hr-border:                   $gray-lighter;
+$hr-border:                   $gray-lighter !default;
diff --git a/yeti/_variables.scss b/yeti/_variables.scss
index a47746f7..cdcb2db5 100644
--- a/yeti/_variables.scss
+++ b/yeti/_variables.scss
@@ -7,18 +7,18 @@
 //
 //## Gray and brand colors for use across Bootstrap.
 
-$gray-base:              #000;
-$gray-darker:            lighten($gray-base, 13.5%); // #222
-$gray-dark:              lighten($gray-base, 20%);   // #333
-$gray:                   #6f6f6f; // #555
-$gray-light:             lighten($gray-base, 60%);   // #999
-$gray-lighter:           lighten($gray-base, 93.5%); // #eee
+$gray-base:              #000 !default;
+$gray-darker:            lighten($gray-base, 13.5%) !default; // #222
+$gray-dark:              lighten($gray-base, 20%) !default;   // #333
+$gray:                   #6f6f6f !default; // #555
+$gray-light:             lighten($gray-base, 60%) !default;   // #999
+$gray-lighter:           lighten($gray-base, 93.5%) !default; // #eee
 
-$brand-primary:         #008cba;
-$brand-success:         #43ac6a;
-$brand-info:            #5bc0de;
-$brand-warning:         #E99002;
-$brand-danger:          #F04124;
+$brand-primary:         #008cba !default;
+$brand-success:         #43ac6a !default;
+$brand-info:            #5bc0de !default;
+$brand-warning:         #E99002 !default;
+$brand-danger:          #F04124 !default;
 
 
 //== Scaffolding
@@ -26,49 +26,49 @@ $brand-danger:          #F04124;
 //## Settings for some of the most global styles.
 
 //** Background color for ``.
-$body-bg:               #fff;
+$body-bg:               #fff !default;
 //** Global text color on ``.
-$text-color:            $gray-darker;
+$text-color:            $gray-darker !default;
 
 //** Global textual link color.
-$link-color:            $brand-primary;
+$link-color:            $brand-primary !default;
 //** Link hover color set via `darken()` function.
-$link-hover-color:      $link-color;
+$link-hover-color:      $link-color !default;
 //** Link hover decoration.
-$link-hover-decoration: underline;
+$link-hover-decoration: underline !default;
 
 
 //== Typography
 //
 //## Font, line-height, and color for body text, headings, and more.
 
-$font-family-sans-serif:  "Open Sans", "Helvetica Neue", Helvetica, Arial, sans-serif;
-$font-family-serif:       Georgia, "Times New Roman", Times, serif;
+$font-family-sans-serif:  "Open Sans", "Helvetica Neue", Helvetica, Arial, sans-serif !default;
+$font-family-serif:       Georgia, "Times New Roman", Times, serif !default;
 //** Default monospace fonts for ``, ``, and `
`.
-$font-family-monospace:   Menlo, Monaco, Consolas, "Courier New", monospace;
-$font-family-base:        $font-family-sans-serif;
+$font-family-monospace:   Menlo, Monaco, Consolas, "Courier New", monospace !default;
+$font-family-base:        $font-family-sans-serif !default;
 
-$font-size-base:          15px;
-$font-size-large:         ceil(($font-size-base * 1.25)); // ~18px
-$font-size-small:         12px; // ~12px
+$font-size-base:          15px !default;
+$font-size-large:         ceil(($font-size-base * 1.25)) !default; // ~18px
+$font-size-small:         12px !default; // ~12px
 
-$font-size-h1:            floor(($font-size-base * 2.6)); // ~36px
-$font-size-h2:            floor(($font-size-base * 2.15)); // ~30px
-$font-size-h3:            ceil(($font-size-base * 1.7)); // ~24px
-$font-size-h4:            ceil(($font-size-base * 1.25)); // ~18px
-$font-size-h5:            $font-size-base;
-$font-size-h6:            ceil(($font-size-base * 0.85)); // ~12px
+$font-size-h1:            floor(($font-size-base * 2.6)) !default; // ~36px
+$font-size-h2:            floor(($font-size-base * 2.15)) !default; // ~30px
+$font-size-h3:            ceil(($font-size-base * 1.7)) !default; // ~24px
+$font-size-h4:            ceil(($font-size-base * 1.25)) !default; // ~18px
+$font-size-h5:            $font-size-base !default;
+$font-size-h6:            ceil(($font-size-base * 0.85)) !default; // ~12px
 
 //** Unit-less `line-height` for use in components like buttons.
-$line-height-base:        1.4;
+$line-height-base:        1.4 !default;
 //** Computed "line-height" (`font-size` * `line-height`) for use with `margin`, `padding`, etc.
-$line-height-computed:    floor(($font-size-base * $line-height-base)); // ~20px
+$line-height-computed:    floor(($font-size-base * $line-height-base)) !default; // ~20px
 
 //** By default, this inherits from the ``.
-$headings-font-family:    $font-family-base;
-$headings-font-weight:    300;
-$headings-line-height:    1.1;
-$headings-color:          inherit;
+$headings-font-family:    $font-family-base !default;
+$headings-font-weight:    300 !default;
+$headings-line-height:    1.1 !default;
+$headings-color:          inherit !default;
 
 
 //== Iconography
@@ -76,45 +76,45 @@ $headings-color:          inherit;
 //## Specify custom location and filename of the included Glyphicons icon font. Useful for those including Bootstrap via Bower.
 
 //** Load fonts from this directory.
-$icon-font-path:          "../fonts/";
+$icon-font-path:          "../fonts/" !default;
 //** File name for all font files.
-$icon-font-name:          "glyphicons-halflings-regular";
+$icon-font-name:          "glyphicons-halflings-regular" !default;
 //** Element ID within SVG icon file.
-$icon-font-svg-id:        "glyphicons_halflingsregular";
+$icon-font-svg-id:        "glyphicons_halflingsregular" !default;
 
 
 //== Components
 //
 //## Define common padding and border radius sizes and more. Values based on 14px text and 1.428 line-height (~20px to start).
 
-$padding-base-vertical:     8px;
-$padding-base-horizontal:   12px;
+$padding-base-vertical:     8px !default;
+$padding-base-horizontal:   12px !default;
 
-$padding-large-vertical:    16px;
-$padding-large-horizontal:  20px;
+$padding-large-vertical:    16px !default;
+$padding-large-horizontal:  20px !default;
 
-$padding-small-vertical:    8px;
-$padding-small-horizontal:  12px;
+$padding-small-vertical:    8px !default;
+$padding-small-horizontal:  12px !default;
 
-$padding-xs-vertical:       4px;
-$padding-xs-horizontal:     6px;
+$padding-xs-vertical:       4px !default;
+$padding-xs-horizontal:     6px !default;
 
-$line-height-large:         1.3333333; // extra decimals for Win 8.1 Chrome
-$line-height-small:         1.5;
+$line-height-large:         1.3333333 !default; // extra decimals for Win 8.1 Chrome
+$line-height-small:         1.5 !default;
 
-$border-radius-base:        0;
-$border-radius-large:       0;
-$border-radius-small:       0;
+$border-radius-base:        0 !default;
+$border-radius-large:       0 !default;
+$border-radius-small:       0 !default;
 
 //** Global color for active items (e.g., navs or dropdowns).
-$component-active-color:    #fff;
+$component-active-color:    #fff !default;
 //** Global background color for active items (e.g., navs or dropdowns).
-$component-active-bg:       $brand-primary;
+$component-active-bg:       $brand-primary !default;
 
 //** Width of the `border` for generating carets that indicator dropdowns.
-$caret-width-base:          4px;
+$caret-width-base:          4px !default;
 //** Carets increase slightly in size for larger components.
-$caret-width-large:         5px;
+$caret-width-large:         5px !default;
 
 
 //== Tables
@@ -122,53 +122,53 @@ $caret-width-large:         5px;
 //## Customizes the `.table` component with basic values, each used across all table variations.
 
 //** Padding for ``s and ``s.
-$table-cell-padding:            8px;
+$table-cell-padding:            8px !default;
 //** Padding for cells in `.table-condensed`.
-$table-condensed-cell-padding:  5px;
+$table-condensed-cell-padding:  5px !default;
 
 //** Default background color used for all tables.
-$table-bg:                      transparent;
+$table-bg:                      transparent !default;
 //** Background color used for `.table-striped`.
-$table-bg-accent:               #f9f9f9;
+$table-bg-accent:               #f9f9f9 !default;
 //** Background color used for `.table-hover`.
-$table-bg-hover:                #f5f5f5;
-$table-bg-active:               $table-bg-hover;
+$table-bg-hover:                #f5f5f5 !default;
+$table-bg-active:               $table-bg-hover !default;
 
 //** Border color for table and cell borders.
-$table-border-color:            #ddd;
+$table-border-color:            #ddd !default;
 
 
 //== Buttons
 //
 //## For each of Bootstrap's buttons, define text, background and border color.
 
-$btn-font-weight:                normal;
+$btn-font-weight:                normal !default;
 
-$btn-default-color:              $gray-dark;
-$btn-default-bg:                 #e7e7e7;
-$btn-default-border:             #ccc;
+$btn-default-color:              $gray-dark !default;
+$btn-default-bg:                 #e7e7e7 !default;
+$btn-default-border:             #ccc !default;
 
-$btn-primary-color:              #fff;
-$btn-primary-bg:                 $brand-primary;
-$btn-primary-border:             darken($btn-primary-bg, 5%);
+$btn-primary-color:              #fff !default;
+$btn-primary-bg:                 $brand-primary !default;
+$btn-primary-border:             darken($btn-primary-bg, 5%) !default;
 
-$btn-success-color:              #fff;
-$btn-success-bg:                 $brand-success;
-$btn-success-border:             darken($btn-success-bg, 5%);
+$btn-success-color:              #fff !default;
+$btn-success-bg:                 $brand-success !default;
+$btn-success-border:             darken($btn-success-bg, 5%) !default;
 
-$btn-info-color:                 #fff;
-$btn-info-bg:                    $brand-info;
-$btn-info-border:                darken($btn-info-bg, 5%);
+$btn-info-color:                 #fff !default;
+$btn-info-bg:                    $brand-info !default;
+$btn-info-border:                darken($btn-info-bg, 5%) !default;
 
-$btn-warning-color:              #fff;
-$btn-warning-bg:                 $brand-warning;
-$btn-warning-border:             darken($btn-warning-bg, 5%);
+$btn-warning-color:              #fff !default;
+$btn-warning-bg:                 $brand-warning !default;
+$btn-warning-border:             darken($btn-warning-bg, 5%) !default;
 
-$btn-danger-color:               #fff;
-$btn-danger-bg:                  $brand-danger;
-$btn-danger-border:              darken($btn-danger-bg, 5%);
+$btn-danger-color:               #fff !default;
+$btn-danger-bg:                  $brand-danger !default;
+$btn-danger-border:              darken($btn-danger-bg, 5%) !default;
 
-$btn-link-disabled-color:        $gray-light;
+$btn-link-disabled-color:        $gray-light !default;
 
 
 //== Forms
@@ -176,50 +176,50 @@ $btn-link-disabled-color:        $gray-light;
 //##
 
 //** `` background color
-$input-bg:                       #fff;
+$input-bg:                       #fff !default;
 //** `` background color
-$input-bg-disabled:              $gray-lighter;
+$input-bg-disabled:              $gray-lighter !default;
 
 //** Text color for ``s
-$input-color:                    $gray;
+$input-color:                    $gray !default;
 //** `` border color
-$input-border:                   #ccc;
+$input-border:                   #ccc !default;
 
 // TODO: Rename `$input-border-radius` to `$input-border-radius-base` in v4
 //** Default `.form-control` border radius
 // This has no effect on ``s in CSS.
-$input-border-radius:            $border-radius-base;
+$input-border-radius:            $border-radius-base !default;
 //** Large `.form-control` border radius
-$input-border-radius-large:      $border-radius-large;
+$input-border-radius-large:      $border-radius-large !default;
 //** Small `.form-control` border radius
-$input-border-radius-small:      $border-radius-small;
+$input-border-radius-small:      $border-radius-small !default;
 
 //** Border color for inputs on focus
-$input-border-focus:             #66afe9;
+$input-border-focus:             #66afe9 !default;
 
 //** Placeholder text color
-$input-color-placeholder:        $gray-light;
+$input-color-placeholder:        $gray-light !default;
 
 //** Default `.form-control` height
-$input-height-base:              ($line-height-computed + ($padding-base-vertical * 2) + 2);
+$input-height-base:              ($line-height-computed + ($padding-base-vertical * 2) + 2) !default;
 //** Large `.form-control` height
-$input-height-large:             (ceil($font-size-large * $line-height-large) + ($padding-large-vertical * 2) + 2);
+$input-height-large:             (ceil($font-size-large * $line-height-large) + ($padding-large-vertical * 2) + 2) !default;
 //** Small `.form-control` height
-$input-height-small:             (floor($font-size-small * $line-height-small) + ($padding-small-vertical * 2) + 2);
+$input-height-small:             (floor($font-size-small * $line-height-small) + ($padding-small-vertical * 2) + 2) !default;
 
 //** `.form-group` margin
-$form-group-margin-bottom:       15px;
+$form-group-margin-bottom:       15px !default;
 
-$legend-color:                   $gray-dark;
-$legend-border-color:            #e5e5e5;
+$legend-color:                   $gray-dark !default;
+$legend-border-color:            #e5e5e5 !default;
 
 //** Background color for textual input addons
-$input-group-addon-bg:           $gray-lighter;
+$input-group-addon-bg:           $gray-lighter !default;
 //** Border color for textual input addons
-$input-group-addon-border-color: $input-border;
+$input-group-addon-border-color: $input-border !default;
 
 //** Disabled cursor for form controls and buttons.
-$cursor-disabled:                not-allowed;
+$cursor-disabled:                not-allowed !default;
 
 
 //== Dropdowns
@@ -227,34 +227,34 @@ $cursor-disabled:                not-allowed;
 //## Dropdown menu container and contents.
 
 //** Background for the dropdown menu.
-$dropdown-bg:                    #fff;
+$dropdown-bg:                    #fff !default;
 //** Dropdown menu `border-color`.
-$dropdown-border:                rgba(0,0,0,.15);
+$dropdown-border:                rgba(0,0,0,.15) !default;
 //** Dropdown menu `border-color` **for IE8**.
-$dropdown-fallback-border:       #ccc;
+$dropdown-fallback-border:       #ccc !default;
 //** Divider color for between dropdown items.
-$dropdown-divider-bg:            rgba(0,0,0,.2);
+$dropdown-divider-bg:            rgba(0,0,0,.2) !default;
 
 //** Dropdown link text color.
-$dropdown-link-color:            #555;
+$dropdown-link-color:            #555 !default;
 //** Hover color for dropdown links.
-$dropdown-link-hover-color:      darken($gray-dark, 5%);
+$dropdown-link-hover-color:      darken($gray-dark, 5%) !default;
 //** Hover background for dropdown links.
-$dropdown-link-hover-bg:         #eee;
+$dropdown-link-hover-bg:         #eee !default;
 
 //** Active dropdown menu item text color.
-$dropdown-link-active-color:     $component-active-color;
+$dropdown-link-active-color:     $component-active-color !default;
 //** Active dropdown menu item background color.
-$dropdown-link-active-bg:        $component-active-bg;
+$dropdown-link-active-bg:        $component-active-bg !default;
 
 //** Disabled dropdown menu item background color.
-$dropdown-link-disabled-color:   $gray-light;
+$dropdown-link-disabled-color:   $gray-light !default;
 
 //** Text color for headers within dropdown menus.
-$dropdown-header-color:          $gray-light;
+$dropdown-header-color:          $gray-light !default;
 
 //** Deprecated `$dropdown-caret-color` as of v3.1.0
-$dropdown-caret-color:           #000;
+$dropdown-caret-color:           #000 !default;
 
 
 //-- Z-index master list
@@ -264,13 +264,13 @@ $dropdown-caret-color:           #000;
 //
 // Note: These variables are not generated into the Customizer.
 
-$zindex-navbar:            1000;
-$zindex-dropdown:          1000;
-$zindex-popover:           1060;
-$zindex-tooltip:           1070;
-$zindex-navbar-fixed:      1030;
-$zindex-modal-background:  1040;
-$zindex-modal:             1050;
+$zindex-navbar:            1000 !default;
+$zindex-dropdown:          1000 !default;
+$zindex-popover:           1060 !default;
+$zindex-tooltip:           1070 !default;
+$zindex-navbar-fixed:      1030 !default;
+$zindex-modal-background:  1040 !default;
+$zindex-modal:             1050 !default;
 
 
 //== Media queries breakpoints
@@ -279,37 +279,37 @@ $zindex-modal:             1050;
 
 // Extra small screen / phone
 //** Deprecated `$screen-xs` as of v3.0.1
-$screen-xs:                  480px;
+$screen-xs:                  480px !default;
 //** Deprecated `$screen-xs-min` as of v3.2.0
-$screen-xs-min:              $screen-xs;
+$screen-xs-min:              $screen-xs !default;
 //** Deprecated `$screen-phone` as of v3.0.1
-$screen-phone:               $screen-xs-min;
+$screen-phone:               $screen-xs-min !default;
 
 // Small screen / tablet
 //** Deprecated `$screen-sm` as of v3.0.1
-$screen-sm:                  768px;
-$screen-sm-min:              $screen-sm;
+$screen-sm:                  768px !default;
+$screen-sm-min:              $screen-sm !default;
 //** Deprecated `$screen-tablet` as of v3.0.1
-$screen-tablet:              $screen-sm-min;
+$screen-tablet:              $screen-sm-min !default;
 
 // Medium screen / desktop
 //** Deprecated `$screen-md` as of v3.0.1
-$screen-md:                  992px;
-$screen-md-min:              $screen-md;
+$screen-md:                  992px !default;
+$screen-md-min:              $screen-md !default;
 //** Deprecated `$screen-desktop` as of v3.0.1
-$screen-desktop:             $screen-md-min;
+$screen-desktop:             $screen-md-min !default;
 
 // Large screen / wide desktop
 //** Deprecated `$screen-lg` as of v3.0.1
-$screen-lg:                  1200px;
-$screen-lg-min:              $screen-lg;
+$screen-lg:                  1200px !default;
+$screen-lg-min:              $screen-lg !default;
 //** Deprecated `$screen-lg-desktop` as of v3.0.1
-$screen-lg-desktop:          $screen-lg-min;
+$screen-lg-desktop:          $screen-lg-min !default;
 
 // So media queries don't overlap when required, provide a maximum
-$screen-xs-max:              ($screen-sm-min - 1);
-$screen-sm-max:              ($screen-md-min - 1);
-$screen-md-max:              ($screen-lg-min - 1);
+$screen-xs-max:              ($screen-sm-min - 1) !default;
+$screen-sm-max:              ($screen-md-min - 1) !default;
+$screen-md-max:              ($screen-lg-min - 1) !default;
 
 
 //== Grid system
@@ -317,14 +317,14 @@ $screen-md-max:              ($screen-lg-min - 1);
 //## Define your custom responsive grid.
 
 //** Number of columns in the grid.
-$grid-columns:              12;
+$grid-columns:              12 !default;
 //** Padding between columns. Gets divided in half for the left and right.
-$grid-gutter-width:         30px;
+$grid-gutter-width:         30px !default;
 // Navbar collapse
 //** Point at which the navbar becomes uncollapsed.
-$grid-float-breakpoint:     $screen-sm-min;
+$grid-float-breakpoint:     $screen-sm-min !default;
 //** Point at which the navbar begins collapsing.
-$grid-float-breakpoint-max: ($grid-float-breakpoint - 1);
+$grid-float-breakpoint-max: ($grid-float-breakpoint - 1) !default;
 
 
 //== Container sizes
@@ -332,19 +332,19 @@ $grid-float-breakpoint-max: ($grid-float-breakpoint - 1);
 //## Define the maximum width of `.container` for different screen sizes.
 
 // Small screen / tablet
-$container-tablet:             (720px + $grid-gutter-width);
+$container-tablet:             (720px + $grid-gutter-width) !default;
 //** For `$screen-sm-min` and up.
-$container-sm:                 $container-tablet;
+$container-sm:                 $container-tablet !default;
 
 // Medium screen / desktop
-$container-desktop:            (940px + $grid-gutter-width);
+$container-desktop:            (940px + $grid-gutter-width) !default;
 //** For `$screen-md-min` and up.
-$container-md:                 $container-desktop;
+$container-md:                 $container-desktop !default;
 
 // Large screen / wide desktop
-$container-large-desktop:      (1140px + $grid-gutter-width);
+$container-large-desktop:      (1140px + $grid-gutter-width) !default;
 //** For `$screen-lg-min` and up.
-$container-lg:                 $container-large-desktop;
+$container-lg:                 $container-large-desktop !default;
 
 
 //== Navbar
@@ -352,61 +352,61 @@ $container-lg:                 $container-large-desktop;
 //##
 
 // Basics of a navbar
-$navbar-height:                    45px;
-$navbar-margin-bottom:             $line-height-computed;
-$navbar-border-radius:             $border-radius-base;
-$navbar-padding-horizontal:        floor(($grid-gutter-width / 2));
-$navbar-padding-vertical:          (($navbar-height - $line-height-computed) / 2);
-$navbar-collapse-max-height:       340px;
+$navbar-height:                    45px !default;
+$navbar-margin-bottom:             $line-height-computed !default;
+$navbar-border-radius:             $border-radius-base !default;
+$navbar-padding-horizontal:        floor(($grid-gutter-width / 2)) !default;
+$navbar-padding-vertical:          (($navbar-height - $line-height-computed) / 2) !default;
+$navbar-collapse-max-height:       340px !default;
 
-$navbar-default-color:             #fff;
-$navbar-default-bg:                $gray-dark;
-$navbar-default-border:            darken($navbar-default-bg, 6.5%);
+$navbar-default-color:             #fff !default;
+$navbar-default-bg:                $gray-dark !default;
+$navbar-default-border:            darken($navbar-default-bg, 6.5%) !default;
 
 // Navbar links
-$navbar-default-link-color:                #fff;
-$navbar-default-link-hover-color:          #fff;
-$navbar-default-link-hover-bg:             #272727;
-$navbar-default-link-active-color:         #fff;
-$navbar-default-link-active-bg:            #272727;
-$navbar-default-link-disabled-color:       #ccc;
-$navbar-default-link-disabled-bg:          transparent;
+$navbar-default-link-color:                #fff !default;
+$navbar-default-link-hover-color:          #fff !default;
+$navbar-default-link-hover-bg:             #272727 !default;
+$navbar-default-link-active-color:         #fff !default;
+$navbar-default-link-active-bg:            #272727 !default;
+$navbar-default-link-disabled-color:       #ccc !default;
+$navbar-default-link-disabled-bg:          transparent !default;
 
 // Navbar brand label
-$navbar-default-brand-color:               $navbar-default-link-color;
-$navbar-default-brand-hover-color:         $navbar-default-brand-color;
-$navbar-default-brand-hover-bg:            transparent;
+$navbar-default-brand-color:               $navbar-default-link-color !default;
+$navbar-default-brand-hover-color:         $navbar-default-brand-color !default;
+$navbar-default-brand-hover-bg:            transparent !default;
 
 // Navbar toggle
-$navbar-default-toggle-hover-bg:           transparent;
-$navbar-default-toggle-icon-bar-bg:        #fff;
-$navbar-default-toggle-border-color:       transparent;
+$navbar-default-toggle-hover-bg:           transparent !default;
+$navbar-default-toggle-icon-bar-bg:        #fff !default;
+$navbar-default-toggle-border-color:       transparent !default;
 
 
 // Inverted navbar
 // Reset inverted navbar basics
-$navbar-inverse-color:                      #fff;
-$navbar-inverse-bg:                         $brand-primary;
-$navbar-inverse-border:                     darken($navbar-inverse-bg, 10%);
+$navbar-inverse-color:                      #fff !default;
+$navbar-inverse-bg:                         $brand-primary !default;
+$navbar-inverse-border:                     darken($navbar-inverse-bg, 10%) !default;
 
 // Inverted navbar links
-$navbar-inverse-link-color:                 #fff;
-$navbar-inverse-link-hover-color:           #fff;
-$navbar-inverse-link-hover-bg:              darken($navbar-inverse-bg, 10%);
-$navbar-inverse-link-active-color:          #fff;
-$navbar-inverse-link-active-bg:             darken($navbar-inverse-bg, 10%);
-$navbar-inverse-link-disabled-color:        #444;
-$navbar-inverse-link-disabled-bg:           transparent;
+$navbar-inverse-link-color:                 #fff !default;
+$navbar-inverse-link-hover-color:           #fff !default;
+$navbar-inverse-link-hover-bg:              darken($navbar-inverse-bg, 10%) !default;
+$navbar-inverse-link-active-color:          #fff !default;
+$navbar-inverse-link-active-bg:             darken($navbar-inverse-bg, 10%) !default;
+$navbar-inverse-link-disabled-color:        #444 !default;
+$navbar-inverse-link-disabled-bg:           transparent !default;
 
 // Inverted navbar brand label
-$navbar-inverse-brand-color:                $navbar-inverse-link-color;
-$navbar-inverse-brand-hover-color:          #fff;
-$navbar-inverse-brand-hover-bg:             transparent;
+$navbar-inverse-brand-color:                $navbar-inverse-link-color !default;
+$navbar-inverse-brand-hover-color:          #fff !default;
+$navbar-inverse-brand-hover-bg:             transparent !default;
 
 // Inverted navbar toggle
-$navbar-inverse-toggle-hover-bg:            transparent;
-$navbar-inverse-toggle-icon-bar-bg:         #fff;
-$navbar-inverse-toggle-border-color:        transparent;
+$navbar-inverse-toggle-hover-bg:            transparent !default;
+$navbar-inverse-toggle-icon-bar-bg:         #fff !default;
+$navbar-inverse-toggle-border-color:        transparent !default;
 
 
 //== Navs
@@ -414,97 +414,97 @@ $navbar-inverse-toggle-border-color:        transparent;
 //##
 
 //=== Shared nav styles
-$nav-link-padding:                          10px 15px;
-$nav-link-hover-bg:                         $gray-lighter;
+$nav-link-padding:                          10px 15px !default;
+$nav-link-hover-bg:                         $gray-lighter !default;
 
-$nav-disabled-link-color:                   $gray-light;
-$nav-disabled-link-hover-color:             $gray-light;
+$nav-disabled-link-color:                   $gray-light !default;
+$nav-disabled-link-hover-color:             $gray-light !default;
 
 //== Tabs
-$nav-tabs-border-color:                     $table-border-color;
+$nav-tabs-border-color:                     $table-border-color !default;
 
-$nav-tabs-link-hover-border-color:          $gray-lighter;
+$nav-tabs-link-hover-border-color:          $gray-lighter !default;
 
-$nav-tabs-active-link-hover-bg:             $body-bg;
-$nav-tabs-active-link-hover-color:          $gray;
-$nav-tabs-active-link-hover-border-color:   $table-border-color;
+$nav-tabs-active-link-hover-bg:             $body-bg !default;
+$nav-tabs-active-link-hover-color:          $gray !default;
+$nav-tabs-active-link-hover-border-color:   $table-border-color !default;
 
-$nav-tabs-justified-link-border-color:            $table-border-color;
-$nav-tabs-justified-active-link-border-color:     $body-bg;
+$nav-tabs-justified-link-border-color:            $table-border-color !default;
+$nav-tabs-justified-active-link-border-color:     $body-bg !default;
 
 //== Pills
-$nav-pills-border-radius:                   $border-radius-base;
-$nav-pills-active-link-hover-bg:            $component-active-bg;
-$nav-pills-active-link-hover-color:         $component-active-color;
+$nav-pills-border-radius:                   $border-radius-base !default;
+$nav-pills-active-link-hover-bg:            $component-active-bg !default;
+$nav-pills-active-link-hover-color:         $component-active-color !default;
 
 
 //== Pagination
 //
 //##
 
-$pagination-color:                     $link-color;
-$pagination-bg:                        transparent;
-$pagination-border:                    transparent;
+$pagination-color:                     $link-color !default;
+$pagination-bg:                        transparent !default;
+$pagination-border:                    transparent !default;
 
-$pagination-hover-color:               $link-hover-color;
-$pagination-hover-bg:                  $gray-lighter;
-$pagination-hover-border:              transparent;
+$pagination-hover-color:               $link-hover-color !default;
+$pagination-hover-bg:                  $gray-lighter !default;
+$pagination-hover-border:              transparent !default;
 
-$pagination-active-color:              #fff;
-$pagination-active-bg:                 $brand-primary;
-$pagination-active-border:             transparent;
+$pagination-active-color:              #fff !default;
+$pagination-active-bg:                 $brand-primary !default;
+$pagination-active-border:             transparent !default;
 
-$pagination-disabled-color:            $gray-light;
-$pagination-disabled-bg:               #fff;
-$pagination-disabled-border:           transparent;
+$pagination-disabled-color:            $gray-light !default;
+$pagination-disabled-bg:               #fff !default;
+$pagination-disabled-border:           transparent !default;
 
 
 //== Pager
 //
 //##
 
-$pager-bg:                             $pagination-bg;
-$pager-border:                         $pagination-border;
-$pager-border-radius:                  3px;
+$pager-bg:                             $pagination-bg !default;
+$pager-border:                         $pagination-border !default;
+$pager-border-radius:                  3px !default;
 
-$pager-hover-bg:                       $pagination-hover-bg;
+$pager-hover-bg:                       $pagination-hover-bg !default;
 
-$pager-active-bg:                      $pagination-active-bg;
-$pager-active-color:                   $pagination-active-color;
+$pager-active-bg:                      $pagination-active-bg !default;
+$pager-active-color:                   $pagination-active-color !default;
 
-$pager-disabled-color:                 $gray-light;
+$pager-disabled-color:                 $gray-light !default;
 
 
 //== Jumbotron
 //
 //##
 
-$jumbotron-padding:              30px;
-$jumbotron-color:                inherit;
-$jumbotron-bg:                   #fafafa;
-$jumbotron-heading-color:        inherit;
-$jumbotron-font-size:            ceil(($font-size-base * 1.5));
+$jumbotron-padding:              30px !default;
+$jumbotron-color:                inherit !default;
+$jumbotron-bg:                   #fafafa !default;
+$jumbotron-heading-color:        inherit !default;
+$jumbotron-font-size:            ceil(($font-size-base * 1.5)) !default;
 
 
 //== Form states and alerts
 //
 //## Define colors for form feedback states and, by default, alerts.
 
-$state-success-text:             $brand-success;
-$state-success-bg:               #dff0d8;
-$state-success-border:           darken($state-success-text, 5%);
+$state-success-text:             $brand-success !default;
+$state-success-bg:               #dff0d8 !default;
+$state-success-border:           darken($state-success-text, 5%) !default;
 
-$state-info-text:                $brand-info;
-$state-info-bg:                  #d9edf7;
-$state-info-border:              darken($state-info-text, 7%);
+$state-info-text:                $brand-info !default;
+$state-info-bg:                  #d9edf7 !default;
+$state-info-border:              darken($state-info-text, 7%) !default;
 
-$state-warning-text:             $brand-warning;
-$state-warning-bg:               #fcf8e3;
-$state-warning-border:           darken($state-warning-text, 5%);
+$state-warning-text:             $brand-warning !default;
+$state-warning-bg:               #fcf8e3 !default;
+$state-warning-border:           darken($state-warning-text, 5%) !default;
 
-$state-danger-text:              $brand-danger;
-$state-danger-bg:                #f2dede;
-$state-danger-border:            darken($state-danger-text, 5%);
+$state-danger-text:              $brand-danger !default;
+$state-danger-bg:                #f2dede !default;
+$state-danger-border:            darken($state-danger-text, 5%) !default;
 
 
 //== Tooltips
@@ -512,17 +512,17 @@ $state-danger-border:            darken($state-danger-text, 5%);
 //##
 
 //** Tooltip max width
-$tooltip-max-width:           200px;
+$tooltip-max-width:           200px !default;
 //** Tooltip text color
-$tooltip-color:               #fff;
+$tooltip-color:               #fff !default;
 //** Tooltip background color
-$tooltip-bg:                  $gray-dark;
-$tooltip-opacity:             .9;
+$tooltip-bg:                  $gray-dark !default;
+$tooltip-opacity:             .9 !default;
 
 //** Tooltip arrow width
-$tooltip-arrow-width:         5px;
+$tooltip-arrow-width:         5px !default;
 //** Tooltip arrow color
-$tooltip-arrow-color:         $tooltip-bg;
+$tooltip-arrow-color:         $tooltip-bg !default;
 
 
 //== Popovers
@@ -530,28 +530,28 @@ $tooltip-arrow-color:         $tooltip-bg;
 //##
 
 //** Popover body background color
-$popover-bg:                          $gray-dark;
+$popover-bg:                          $gray-dark !default;
 //** Popover maximum width
-$popover-max-width:                   276px;
+$popover-max-width:                   276px !default;
 //** Popover border color
-$popover-border-color:                transparent;
+$popover-border-color:                transparent !default;
 //** Popover fallback border color
-$popover-fallback-border-color:       $gray-dark;
+$popover-fallback-border-color:       $gray-dark !default;
 
 //** Popover title background color
-$popover-title-bg:                    $popover-bg;
+$popover-title-bg:                    $popover-bg !default;
 
 //** Popover arrow width
-$popover-arrow-width:                 10px;
+$popover-arrow-width:                 10px !default;
 //** Popover arrow color
-$popover-arrow-color:                 $popover-bg;
+$popover-arrow-color:                 $popover-bg !default;
 
 //** Popover outer arrow width
-$popover-arrow-outer-width:           ($popover-arrow-width + 1);
+$popover-arrow-outer-width:           ($popover-arrow-width + 1) !default;
 //** Popover outer arrow color
-$popover-arrow-outer-color:           fadein($popover-border-color, 5%);
+$popover-arrow-outer-color:           fadein($popover-border-color, 5%) !default;
 //** Popover outer arrow fallback color
-$popover-arrow-outer-fallback-color:  darken($popover-fallback-border-color, 20%);
+$popover-arrow-outer-fallback-color:  darken($popover-fallback-border-color, 20%) !default;
 
 
 //== Labels
@@ -559,22 +559,22 @@ $popover-arrow-outer-fallback-color:  darken($popover-fallback-border-color, 20%
 //##
 
 //** Default label background color
-$label-default-bg:            $gray-light;
+$label-default-bg:            $gray-light !default;
 //** Primary label background color
-$label-primary-bg:            $brand-primary;
+$label-primary-bg:            $brand-primary !default;
 //** Success label background color
-$label-success-bg:            $brand-success;
+$label-success-bg:            $brand-success !default;
 //** Info label background color
-$label-info-bg:               $brand-info;
+$label-info-bg:               $brand-info !default;
 //** Warning label background color
-$label-warning-bg:            $brand-warning;
+$label-warning-bg:            $brand-warning !default;
 //** Danger label background color
-$label-danger-bg:             $brand-danger;
+$label-danger-bg:             $brand-danger !default;
 
 //** Default label text color
-$label-color:                 #fff;
+$label-color:                 #fff !default;
 //** Default text color of a linked label
-$label-link-hover-color:      #fff;
+$label-link-hover-color:      #fff !default;
 
 
 //== Modals
@@ -582,57 +582,57 @@ $label-link-hover-color:      #fff;
 //##
 
 //** Padding applied to the modal body
-$modal-inner-padding:         20px;
+$modal-inner-padding:         20px !default;
 
 //** Padding applied to the modal title
-$modal-title-padding:         15px;
+$modal-title-padding:         15px !default;
 //** Modal title line-height
-$modal-title-line-height:     $line-height-base;
+$modal-title-line-height:     $line-height-base !default;
 
 //** Background color of modal content area
-$modal-content-bg:                             #fff;
+$modal-content-bg:                             #fff !default;
 //** Modal content border color
-$modal-content-border-color:                   rgba(0,0,0,.2);
+$modal-content-border-color:                   rgba(0,0,0,.2) !default;
 //** Modal content border color **for IE8**
-$modal-content-fallback-border-color:          #999;
+$modal-content-fallback-border-color:          #999 !default;
 
 //** Modal backdrop background color
-$modal-backdrop-bg:           #000;
+$modal-backdrop-bg:           #000 !default;
 //** Modal backdrop opacity
-$modal-backdrop-opacity:      .5;
+$modal-backdrop-opacity:      .5 !default;
 //** Modal header border color
-$modal-header-border-color:   #e5e5e5;
+$modal-header-border-color:   #e5e5e5 !default;
 //** Modal footer border color
-$modal-footer-border-color:   $modal-header-border-color;
+$modal-footer-border-color:   $modal-header-border-color !default;
 
-$modal-lg:                    900px;
-$modal-md:                    600px;
-$modal-sm:                    300px;
+$modal-lg:                    900px !default;
+$modal-md:                    600px !default;
+$modal-sm:                    300px !default;
 
 
 //== Alerts
 //
 //## Define alert colors, border radius, and padding.
 
-$alert-padding:               15px;
-$alert-border-radius:         $border-radius-base;
-$alert-link-font-weight:      bold;
+$alert-padding:               15px !default;
+$alert-border-radius:         $border-radius-base !default;
+$alert-link-font-weight:      bold !default;
 
-$alert-success-bg:            $brand-success;
-$alert-success-text:          #fff;
-$alert-success-border:        $state-success-border;
+$alert-success-bg:            $brand-success !default;
+$alert-success-text:          #fff !default;
+$alert-success-border:        $state-success-border !default;
 
-$alert-info-bg:               $brand-info;
-$alert-info-text:             #fff;
-$alert-info-border:           $state-info-border;
+$alert-info-bg:               $brand-info !default;
+$alert-info-text:             #fff !default;
+$alert-info-border:           $state-info-border !default;
 
-$alert-warning-bg:            $brand-warning;
-$alert-warning-text:          #fff;
-$alert-warning-border:        $state-warning-border;
+$alert-warning-bg:            $brand-warning !default;
+$alert-warning-text:          #fff !default;
+$alert-warning-border:        $state-warning-border !default;
 
-$alert-danger-bg:             $brand-danger;
-$alert-danger-text:           #fff;
-$alert-danger-border:         $state-danger-border;
+$alert-danger-bg:             $brand-danger !default;
+$alert-danger-text:           #fff !default;
+$alert-danger-border:         $state-danger-border !default;
 
 
 //== Progress bars
@@ -640,22 +640,22 @@ $alert-danger-border:         $state-danger-border;
 //##
 
 //** Background color of the whole progress component
-$progress-bg:                 #f5f5f5;
+$progress-bg:                 #f5f5f5 !default;
 //** Progress bar text color
-$progress-bar-color:          #fff;
+$progress-bar-color:          #fff !default;
 //** Variable for setting rounded corners on progress bar.
-$progress-border-radius:      $border-radius-base;
+$progress-border-radius:      $border-radius-base !default;
 
 //** Default progress bar color
-$progress-bar-bg:             $brand-primary;
+$progress-bar-bg:             $brand-primary !default;
 //** Success progress bar color
-$progress-bar-success-bg:     $brand-success;
+$progress-bar-success-bg:     $brand-success !default;
 //** Warning progress bar color
-$progress-bar-warning-bg:     $brand-warning;
+$progress-bar-warning-bg:     $brand-warning !default;
 //** Danger progress bar color
-$progress-bar-danger-bg:      $brand-danger;
+$progress-bar-danger-bg:      $brand-danger !default;
 //** Info progress bar color
-$progress-bar-info-bg:        $brand-info;
+$progress-bar-info-bg:        $brand-info !default;
 
 
 //== List group
@@ -663,72 +663,72 @@ $progress-bar-info-bg:        $brand-info;
 //##
 
 //** Background color on `.list-group-item`
-$list-group-bg:                 #fff;
+$list-group-bg:                 #fff !default;
 //** `.list-group-item` border color
-$list-group-border:             $table-border-color;
+$list-group-border:             $table-border-color !default;
 //** List group border radius
-$list-group-border-radius:      $border-radius-base;
+$list-group-border-radius:      $border-radius-base !default;
 
 //** Background color of single list items on hover
-$list-group-hover-bg:           #f5f5f5;
+$list-group-hover-bg:           #f5f5f5 !default;
 //** Text color of active list items
-$list-group-active-color:       $component-active-color;
+$list-group-active-color:       $component-active-color !default;
 //** Background color of active list items
-$list-group-active-bg:          $component-active-bg;
+$list-group-active-bg:          $component-active-bg !default;
 //** Border color of active list elements
-$list-group-active-border:      $list-group-active-bg;
+$list-group-active-border:      $list-group-active-bg !default;
 //** Text color for content within active list items
-$list-group-active-text-color:  lighten($list-group-active-bg, 40%);
+$list-group-active-text-color:  lighten($list-group-active-bg, 40%) !default;
 
 //** Text color of disabled list items
-$list-group-disabled-color:      $gray-light;
+$list-group-disabled-color:      $gray-light !default;
 //** Background color of disabled list items
-$list-group-disabled-bg:         $gray-lighter;
+$list-group-disabled-bg:         $gray-lighter !default;
 //** Text color for content within disabled list items
-$list-group-disabled-text-color: $list-group-disabled-color;
+$list-group-disabled-text-color: $list-group-disabled-color !default;
 
-$list-group-link-color:         #555;
-$list-group-link-hover-color:   $list-group-link-color;
-$list-group-link-heading-color: #333;
+$list-group-link-color:         #555 !default;
+$list-group-link-hover-color:   $list-group-link-color !default;
+$list-group-link-heading-color: #333 !default;
 
 
 //== Panels
 //
 //##
 
-$panel-bg:                    #fff;
-$panel-body-padding:          15px;
-$panel-heading-padding:       10px 15px;
-$panel-footer-padding:        $panel-heading-padding;
-$panel-border-radius:         $border-radius-base;
+$panel-bg:                    #fff !default;
+$panel-body-padding:          15px !default;
+$panel-heading-padding:       10px 15px !default;
+$panel-footer-padding:        $panel-heading-padding !default;
+$panel-border-radius:         $border-radius-base !default;
 
 //** Border color for elements within panels
-$panel-inner-border:          $table-border-color;
-$panel-footer-bg:             #f5f5f5;
+$panel-inner-border:          $table-border-color !default;
+$panel-footer-bg:             #f5f5f5 !default;
 
-$panel-default-text:          $gray-dark;
-$panel-default-border:        $table-border-color;
-$panel-default-heading-bg:    #f5f5f5;
+$panel-default-text:          $gray-dark !default;
+$panel-default-border:        $table-border-color !default;
+$panel-default-heading-bg:    #f5f5f5 !default;
 
-$panel-primary-text:          #fff;
-$panel-primary-border:        $brand-primary;
-$panel-primary-heading-bg:    $brand-primary;
+$panel-primary-text:          #fff !default;
+$panel-primary-border:        $brand-primary !default;
+$panel-primary-heading-bg:    $brand-primary !default;
 
-$panel-success-text:          #fff;
-$panel-success-border:        $state-success-border;
-$panel-success-heading-bg:    $brand-success;
+$panel-success-text:          #fff !default;
+$panel-success-border:        $state-success-border !default;
+$panel-success-heading-bg:    $brand-success !default;
 
-$panel-info-text:             #fff;
-$panel-info-border:           $state-info-border;
-$panel-info-heading-bg:       $brand-info;
+$panel-info-text:             #fff !default;
+$panel-info-border:           $state-info-border !default;
+$panel-info-heading-bg:       $brand-info !default;
 
-$panel-warning-text:          #fff;
-$panel-warning-border:        $state-warning-border;
-$panel-warning-heading-bg:    $brand-warning;
+$panel-warning-text:          #fff !default;
+$panel-warning-border:        $state-warning-border !default;
+$panel-warning-heading-bg:    $brand-warning !default;
 
-$panel-danger-text:           #fff;
-$panel-danger-border:         $state-danger-border;
-$panel-danger-heading-bg:     $brand-danger;
+$panel-danger-text:           #fff !default;
+$panel-danger-border:         $state-danger-border !default;
+$panel-danger-heading-bg:     $brand-danger !default;
 
 
 //== Thumbnails
@@ -736,103 +736,103 @@ $panel-danger-heading-bg:     $brand-danger;
 //##
 
 //** Padding around the thumbnail image
-$thumbnail-padding:           4px;
+$thumbnail-padding:           4px !default;
 //** Thumbnail background color
-$thumbnail-bg:                $body-bg;
+$thumbnail-bg:                $body-bg !default;
 //** Thumbnail border color
-$thumbnail-border:            $table-border-color;
+$thumbnail-border:            $table-border-color !default;
 //** Thumbnail border radius
-$thumbnail-border-radius:     $border-radius-base;
+$thumbnail-border-radius:     $border-radius-base !default;
 
 //** Custom text color for thumbnail captions
-$thumbnail-caption-color:     $text-color;
+$thumbnail-caption-color:     $text-color !default;
 //** Padding around the thumbnail caption
-$thumbnail-caption-padding:   9px;
+$thumbnail-caption-padding:   9px !default;
 
 
 //== Wells
 //
 //##
 
-$well-bg:                     $jumbotron-bg;
-$well-border:                 darken($well-bg, 7%);
+$well-bg:                     $jumbotron-bg !default;
+$well-border:                 darken($well-bg, 7%) !default;
 
 
 //== Badges
 //
 //##
 
-$badge-color:                 #fff;
+$badge-color:                 #fff !default;
 //** Linked badge text color on hover
-$badge-link-hover-color:      #fff;
-$badge-bg:                    $btn-primary-bg;
+$badge-link-hover-color:      #fff !default;
+$badge-bg:                    $btn-primary-bg !default;
 
 //** Badge text color in active nav link
-$badge-active-color:          $link-color;
+$badge-active-color:          $link-color !default;
 //** Badge background color in active nav link
-$badge-active-bg:             #fff;
+$badge-active-bg:             #fff !default;
 
-$badge-font-weight:           bold;
-$badge-line-height:           1;
-$badge-border-radius:         10px;
+$badge-font-weight:           bold !default;
+$badge-line-height:           1 !default;
+$badge-border-radius:         10px !default;
 
 
 //== Breadcrumbs
 //
 //##
 
-$breadcrumb-padding-vertical:   8px;
-$breadcrumb-padding-horizontal: 15px;
+$breadcrumb-padding-vertical:   8px !default;
+$breadcrumb-padding-horizontal: 15px !default;
 //** Breadcrumb background color
-$breadcrumb-bg:                 #f5f5f5;
+$breadcrumb-bg:                 #f5f5f5 !default;
 //** Breadcrumb text color
-$breadcrumb-color:              $gray-light;
+$breadcrumb-color:              $gray-light !default;
 //** Text color of current page in the breadcrumb
-$breadcrumb-active-color:       $gray-dark;
+$breadcrumb-active-color:       $gray-dark !default;
 //** Textual separator for between breadcrumb elements
-$breadcrumb-separator:          "/";
+$breadcrumb-separator:          "/" !default;
 
 
 //== Carousel
 //
 //##
 
-$carousel-text-shadow:                        0 1px 2px rgba(0,0,0,.6);
+$carousel-text-shadow:                        0 1px 2px rgba(0,0,0,.6) !default;
 
-$carousel-control-color:                      #fff;
-$carousel-control-width:                      15%;
-$carousel-control-opacity:                    .5;
-$carousel-control-font-size:                  20px;
+$carousel-control-color:                      #fff !default;
+$carousel-control-width:                      15% !default;
+$carousel-control-opacity:                    .5 !default;
+$carousel-control-font-size:                  20px !default;
 
-$carousel-indicator-active-bg:                #fff;
-$carousel-indicator-border-color:             #fff;
+$carousel-indicator-active-bg:                #fff !default;
+$carousel-indicator-border-color:             #fff !default;
 
-$carousel-caption-color:                      #fff;
+$carousel-caption-color:                      #fff !default;
 
 
 //== Close
 //
 //##
 
-$close-font-weight:           bold;
-$close-color:                 #fff;
-$close-text-shadow:           0 1px 0 #fff;
+$close-font-weight:           bold !default;
+$close-color:                 #fff !default;
+$close-text-shadow:           0 1px 0 #fff !default;
 
 
 //== Code
 //
 //##
 
-$code-color:                  #c7254e;
-$code-bg:                     #f9f2f4;
+$code-color:                  #c7254e !default;
+$code-bg:                     #f9f2f4 !default;
 
-$kbd-color:                   #fff;
-$kbd-bg:                      #333;
+$kbd-color:                   #fff !default;
+$kbd-bg:                      #333 !default;
 
-$pre-bg:                      #f5f5f5;
-$pre-color:                   $gray-dark;
-$pre-border-color:            #ccc;
-$pre-scrollable-max-height:   340px;
+$pre-bg:                      #f5f5f5 !default;
+$pre-color:                   $gray-dark !default;
+$pre-border-color:            #ccc !default;
+$pre-scrollable-max-height:   340px !default;
 
 
 //== Type
@@ -840,22 +840,22 @@ $pre-scrollable-max-height:   340px;
 //##
 
 //** Horizontal offset for forms and lists.
-$component-offset-horizontal: 180px;
+$component-offset-horizontal: 180px !default;
 //** Text muted color
-$text-muted:                  $gray-light;
+$text-muted:                  $gray-light !default;
 //** Abbreviations and acronyms border color
-$abbr-border-color:           $gray-light;
+$abbr-border-color:           $gray-light !default;
 //** Headings small color
-$headings-small-color:        $gray-light;
+$headings-small-color:        $gray-light !default;
 //** Blockquote small color
-$blockquote-small-color:      $gray;
+$blockquote-small-color:      $gray !default;
 //** Blockquote font size
-$blockquote-font-size:        ($font-size-base * 1.25);
+$blockquote-font-size:        ($font-size-base * 1.25) !default;
 //** Blockquote border color
-$blockquote-border-color:     $table-border-color;
+$blockquote-border-color:     $table-border-color !default;
 //** Page header border color
-$page-header-border-color:    $table-border-color;
+$page-header-border-color:    $table-border-color !default;
 //** Width of horizontal description list titles
-$dl-horizontal-offset:        $component-offset-horizontal;
+$dl-horizontal-offset:        $component-offset-horizontal !default;
 //** Horizontal line color.
-$hr-border:                   $table-border-color;
+$hr-border:                   $table-border-color !default;
-- 
cgit v1.2.3