bootstrap 4 beta 2

Bootstrap 4 beta 2

bootstap 4 alpha 6/scss/mixins/_alert.scss

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+// Alerts
+
+@mixin alert-variant($background, $border, $body-color) {
+  background-color: $background;
+  border-color: $border;
+  color: $body-color;
+
+  hr {
+    border-top-color: darken($border, 5%);
+  }
+  .alert-link {
+    color: darken($body-color, 10%);
+  }
+}

bootstap 4 alpha 6/scss/mixins/_background-variant.scss

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+// Contextual backgrounds
+
+@mixin bg-variant($parent, $color) {
+  #{$parent} {
+    background-color: $color !important;
+  }
+  a#{$parent} {
+    @include hover-focus {
+      background-color: darken($color, 10%) !important;
+    }
+  }
+}

bootstap 4 alpha 6/scss/mixins/_border-radius.scss

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+// Single side border-radius
+
+@mixin border-radius($radius: $border-radius) {
+  @if $enable-rounded {
+    border-radius: $radius;
+  }
+}
+
+@mixin border-top-radius($radius) {
+  @if $enable-rounded {
+    border-top-right-radius: $radius;
+    border-top-left-radius: $radius;
+  }
+}
+
+@mixin border-right-radius($radius) {
+  @if $enable-rounded {
+    border-bottom-right-radius: $radius;
+    border-top-right-radius: $radius;
+  }
+}
+
+@mixin border-bottom-radius($radius) {
+  @if $enable-rounded {
+    border-bottom-right-radius: $radius;
+    border-bottom-left-radius: $radius;
+  }
+}
+
+@mixin border-left-radius($radius) {
+  @if $enable-rounded {
+    border-bottom-left-radius: $radius;
+    border-top-left-radius: $radius;
+  }
+}

bootstap 4 alpha 6/scss/mixins/_breakpoints.scss

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+// Breakpoint viewport sizes and media queries.
+//
+// Breakpoints are defined as a map of (name: minimum width), order from small to large:
+//
+//    (xs: 0, sm: 544px, md: 768px)
+//
+// The map defined in the `$grid-breakpoints` global variable is used as the `$breakpoints` argument by default.
+
+// Name of the next breakpoint, or null for the last breakpoint.
+//
+//    >> breakpoint-next(sm)
+//    md
+//    >> breakpoint-next(sm, (xs: 0, sm: 544px, md: 768px))
+//    md
+//    >> breakpoint-next(sm, $breakpoint-names: (xs sm md))
+//    md
+@function breakpoint-next($name, $breakpoints: $grid-breakpoints, $breakpoint-names: map-keys($breakpoints)) {
+  $n: index($breakpoint-names, $name);
+  @return if($n < length($breakpoint-names), nth($breakpoint-names, $n + 1), null);
+}
+
+// Minimum breakpoint width. Null for the smallest (first) breakpoint.
+//
+//    >> breakpoint-min(sm, (xs: 0, sm: 544px, md: 768px))
+//    544px
+@function breakpoint-min($name, $breakpoints: $grid-breakpoints) {
+  $min: map-get($breakpoints, $name);
+  @return if($min != 0, $min, null);
+}
+
+// Maximum breakpoint width. Null for the largest (last) breakpoint.
+// The maximum value is calculated as the minimum of the next one less 0.1.
+//
+//    >> breakpoint-max(sm, (xs: 0, sm: 544px, md: 768px))
+//    767px
+@function breakpoint-max($name, $breakpoints: $grid-breakpoints) {
+  $next: breakpoint-next($name, $breakpoints);
+  @return if($next, breakpoint-min($next, $breakpoints) - 1px, null);
+}
+
+// Media of at least the minimum breakpoint width. No query for the smallest breakpoint.
+// Makes the @content apply to the given breakpoint and wider.
+@mixin media-breakpoint-up($name, $breakpoints: $grid-breakpoints) {
+  $min: breakpoint-min($name, $breakpoints);
+  @if $min {
+    @media (min-width: $min) {
+      @content;
+    }
+  } @else {
+    @content;
+  }
+}
+
+// Media of at most the maximum breakpoint width. No query for the largest breakpoint.
+// Makes the @content apply to the given breakpoint and narrower.
+@mixin media-breakpoint-down($name, $breakpoints: $grid-breakpoints) {
+  $max: breakpoint-max($name, $breakpoints);
+  @if $max {
+    @media (max-width: $max) {
+      @content;
+    }
+  } @else {
+    @content;
+  }
+}
+
+// Media between the breakpoint's minimum and maximum widths.
+// No minimum for the smallest breakpoint, and no maximum for the largest one.
+// Makes the @content apply only to the given breakpoint, not viewports any wider or narrower.
+@mixin media-breakpoint-only($name, $breakpoints: $grid-breakpoints) {
+  @include media-breakpoint-up($name, $breakpoints) {
+    @include media-breakpoint-down($name, $breakpoints) {
+      @content;
+    }
+  }
+}
+
+// Media that spans multiple breakpoint widths.
+// Makes the @content apply between the min and max breakpoints
+@mixin media-breakpoint-between($lower, $upper, $breakpoints: $grid-breakpoints) {
+  @include media-breakpoint-up($lower, $breakpoints) {
+    @include media-breakpoint-down($upper, $breakpoints) {
+      @content;
+    }
+  }
+}

bootstap 4 alpha 6/scss/mixins/_buttons.scss

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+// Button variants
+//
+// Easily pump out default styles, as well as :hover, :focus, :active,
+// and disabled options for all buttons
+
+@mixin button-variant($color, $background, $border) {
+  $active-background: darken($background, 10%);
+  $active-border: darken($border, 12%);
+
+  color: $color;
+  background-color: $background;
+  border-color: $border;
+  @include box-shadow($btn-box-shadow);
+
+  @include hover {
+    color: $color;
+    background-color: $active-background;
+        border-color: $active-border;
+  }
+
+  &:focus,
+  &.focus {
+    color: $color;
+    background-color: $active-background;
+        border-color: $active-border;
+  }
+
+  &:active,
+  &.active,
+  .open > &.dropdown-toggle {
+    color: $color;
+    background-color: $active-background;
+        border-color: $active-border;
+    // Remove the gradient for the pressed/active state
+    background-image: none;
+    @include box-shadow($btn-active-box-shadow);
+
+    &:hover,
+    &:focus,
+    &.focus {
+      color: $color;
+      background-color: darken($background, 17%);
+          border-color: darken($border, 25%);
+    }
+  }
+
+  &.disabled,
+  &:disabled {
+    &:focus,
+    &.focus {
+      background-color: $background;
+          border-color: $border;
+    }
+    @include hover {
+      background-color: $background;
+          border-color: $border;
+    }
+  }
+}
+
+@mixin button-outline-variant($color) {
+  color: $color;
+  background-image: none;
+  background-color: transparent;
+  border-color: $color;
+
+  @include hover {
+    color: #fff;
+    background-color: $color;
+        border-color: $color;
+  }
+
+  &:focus,
+  &.focus {
+    color: #fff;
+    background-color: $color;
+        border-color: $color;
+  }
+
+  &:active,
+  &.active,
+  .open > &.dropdown-toggle {
+    color: #fff;
+    background-color: $color;
+        border-color: $color;
+
+    &:hover,
+    &:focus,
+    &.focus {
+      color: #fff;
+      background-color: darken($color, 17%);
+          border-color: darken($color, 25%);
+    }
+  }
+
+  &.disabled,
+  &:disabled {
+    &:focus,
+    &.focus {
+      border-color: lighten($color, 20%);
+    }
+    @include hover {
+      border-color: lighten($color, 20%);
+    }
+  }
+}
+
+// Button sizes
+@mixin button-size($padding-y, $padding-x, $font-size, $border-radius) {
+  padding: $padding-y $padding-x;
+  font-size: $font-size;
+  @include border-radius($border-radius);
+}

bootstap 4 alpha 6/scss/mixins/_cards.scss

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+// Card variants
+
+@mixin card-variant($background, $border) {
+  background-color: $background;
+  border-color: $border;
+
+  .card-header,
+  .card-footer {
+    background-color: transparent;
+  }
+}
+
+@mixin card-outline-variant($color) {
+  background-color: transparent;
+  border-color: $color;
+}
+
+//
+// Inverse text within a card for use with dark backgrounds
+//
+
+@mixin card-inverse {
+  .card-header,
+  .card-footer {
+    border-color: rgba(255,255,255,.2);
+  }
+  .card-header,
+  .card-footer,
+  .card-title,
+  .card-blockquote {
+    color: #fff;
+  }
+  .card-link,
+  .card-text,
+  .card-subtitle,
+  .card-blockquote .blockquote-footer {
+    color: rgba(255,255,255,.65);
+  }
+  .card-link {
+    @include hover-focus {
+      color: $card-link-hover-color;
+    }
+  }
+}

bootstap 4 alpha 6/scss/mixins/_clearfix.scss

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+@mixin clearfix() {
+  &::after {
+    content: "";
+    display: table;
+    clear: both;
+  }
+}

bootstap 4 alpha 6/scss/mixins/_float.scss

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+@mixin float-left {
+  float: left !important;
+}
+@mixin float-right {
+  float: right !important;
+}

bootstap 4 alpha 6/scss/mixins/_forms.scss

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+// Form validation states
+//
+// Used in _forms.scss to generate the form validation CSS for warnings, errors,
+// and successes.
+
+@mixin form-control-validation($color) {
+  // Color the label and help text
+  .form-control-feedback,
+  .form-control-label,
+  .form-check-label,
+  .form-check-inline,
+  .custom-control {
+    color: $color;
+  }
+
+  // Set the border and box shadow on specific inputs to match
+  .form-control {
+    border-color: $color;
+
+    @if $enable-rounded {
+      &:focus {
+        box-shadow: $input-box-shadow, 0 0 6px lighten($color, 20%);
+      }
+    }
+  }
+
+  // Set validation states also for addons
+  .input-group-addon {
+    color: $color;
+    border-color: $color;
+    background-color: lighten($color, 40%);
+  }
+}
+
+// Form control focus state
+//
+// Generate a customized focus state and for any input with the specified color,
+// which defaults to the `@input-border-focus` variable.
+//
+// We highly encourage you to not customize the default value, but instead use
+// this to tweak colors on an as-needed basis. This aesthetic change is based on
+// WebKit's default styles, but applicable to a wider range of browsers. Its
+// usability and accessibility should be taken into account with any change.
+//
+// Example usage: change the default blue border and shadow to white for better
+// contrast against a dark gray background.
+@mixin form-control-focus() {
+  &:focus {
+    color: $input-color-focus;
+    background-color: $input-bg-focus;
+    border-color: $input-border-focus;
+    outline: none;
+    @include box-shadow($input-box-shadow-focus);
+  }
+}
+
+// Form control sizing
+//
+// Relative text size, padding, and border-radii changes for form controls. For
+// horizontal sizing, wrap controls in the predefined grid classes. `<select>`
+// element gets special love because it's special, and that's a fact!
+
+@mixin input-size($parent, $input-height, $padding-y, $padding-x, $font-size, $line-height, $border-radius) {
+  #{$parent} {
+    height: $input-height;
+    padding: $padding-y $padding-x;
+    font-size: $font-size;
+    line-height: $line-height;
+    @include border-radius($border-radius);
+  }
+
+  select#{$parent} {
+    height: $input-height;
+    line-height: $input-height;
+  }
+
+  textarea#{$parent},
+  select[multiple]#{$parent} {
+    height: auto;
+  }
+}

bootstap 4 alpha 6/scss/mixins/_gradients.scss

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+// Gradients
+
+// Horizontal gradient, from left to right
+//
+// Creates two color stops, start and end, by specifying a color and position for each color stop.
+// Color stops are not available in IE9.
+@mixin gradient-x($start-color: #555, $end-color: #333, $start-percent: 0%, $end-percent: 100%) {
+  background-image: linear-gradient(to right, $start-color $start-percent, $end-color $end-percent);
+  background-repeat: repeat-x;
+  filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#{ie-hex-str($start-color)}', endColorstr='#{ie-hex-str($end-color)}', GradientType=1); // IE9
+}
+
+// Vertical gradient, from top to bottom
+//
+// Creates two color stops, start and end, by specifying a color and position for each color stop.
+// Color stops are not available in IE9.
+@mixin gradient-y($start-color: #555, $end-color: #333, $start-percent: 0%, $end-percent: 100%) {
+  background-image: linear-gradient(to bottom, $start-color $start-percent, $end-color $end-percent);
+  background-repeat: repeat-x;
+  filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#{ie-hex-str($start-color)}', endColorstr='#{ie-hex-str($end-color)}', GradientType=0); // IE9
+}
+
+@mixin gradient-directional($start-color: #555, $end-color: #333, $deg: 45deg) {
+  background-repeat: repeat-x;
+  background-image: linear-gradient($deg, $start-color, $end-color);
+}
+@mixin gradient-x-three-colors($start-color: #00b3ee, $mid-color: #7a43b6, $color-stop: 50%, $end-color: #c3325f) {
+  background-image: linear-gradient(to right, $start-color, $mid-color $color-stop, $end-color);
+  background-repeat: no-repeat;
+  filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#{ie-hex-str($start-color)}', endColorstr='#{ie-hex-str($end-color)}', GradientType=1); // IE9 gets no color-stop at all for proper fallback
+}
+@mixin gradient-y-three-colors($start-color: #00b3ee, $mid-color: #7a43b6, $color-stop: 50%, $end-color: #c3325f) {
+  background-image: linear-gradient($start-color, $mid-color $color-stop, $end-color);
+  background-repeat: no-repeat;
+  filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#{ie-hex-str($start-color)}', endColorstr='#{ie-hex-str($end-color)}', GradientType=0); // IE9 gets no color-stop at all for proper fallback
+}
+@mixin gradient-radial($inner-color: #555, $outer-color: #333) {
+  background-image: radial-gradient(circle, $inner-color, $outer-color);
+  background-repeat: no-repeat;
+}
+@mixin gradient-striped($color: rgba(255,255,255,.15), $angle: 45deg) {
+  background-image: linear-gradient($angle, $color 25%, transparent 25%, transparent 50%, $color 50%, $color 75%, transparent 75%, transparent);
+}

bootstap 4 alpha 6/scss/mixins/_grid-framework.scss

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+// Framework grid generation
+//
+// Used only by Bootstrap to generate the correct number of grid classes given
+// any value of `$grid-columns`.
+
+@mixin make-grid-columns($columns: $grid-columns, $gutters: $grid-gutter-widths, $breakpoints: $grid-breakpoints) {
+  // Common properties for all breakpoints
+  %grid-column {
+    position: relative;
+    // Prevent columns from collapsing when empty
+    min-height: 1px;
+
+    @if $enable-flex {
+      width: 100%;
+    }
+
+    @include make-gutters($gutters);
+  }
+
+  $breakpoint-counter: 0;
+  @each $breakpoint in map-keys($breakpoints) {
+    $breakpoint-counter: ($breakpoint-counter + 1);
+
+    // Allow columns to stretch full width below their breakpoints
+    .col-#{$breakpoint} {
+      @extend %grid-column;
+    }
+
+    @for $i from 1 through $columns {
+      .col-#{$breakpoint}-#{$i} {
+        @extend %grid-column;
+      }
+    }
+
+    @include media-breakpoint-up($breakpoint, $breakpoints) {
+      // Provide basic `.col-{bp}` classes for equal-width flexbox columns
+      @if $enable-flex {
+        .col-#{$breakpoint} {
+          flex-basis: 0;
+          flex-grow: 1;
+          max-width: 100%;
+        }
+      }
+
+      @for $i from 1 through $columns {
+        .col-#{$breakpoint}-#{$i} {
+          @include make-col($i, $columns);
+        }
+      }
+
+      @each $modifier in (pull, push) {
+        @for $i from 0 through $columns {
+          .#{$modifier}-#{$breakpoint}-#{$i} {
+            @include make-col-modifier($modifier, $i, $columns)
+          }
+        }
+      }
+
+      // `$columns - 1` because offsetting by the width of an entire row isn't possible
+      @for $i from 0 through ($columns - 1) {
+        @if $breakpoint-counter != 1 or $i != 0 { // Avoid emitting useless .offset-xs-0
+          .offset-#{$breakpoint}-#{$i} {
+            @include make-col-modifier(offset, $i, $columns)
+          }
+        }
+      }
+    }
+  }
+}

bootstap 4 alpha 6/scss/mixins/_grid.scss

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+/// Grid system
+//
+// Generate semantic grid columns with these mixins.
+
+@mixin make-container($gutter: $grid-gutter-width-base) {
+  margin-left: auto;
+  margin-right: auto;
+  padding-left:  ($gutter / 2);
+  padding-right: ($gutter / 2);
+  @if not $enable-flex {
+    @include clearfix();
+  }
+}
+
+
+// For each breakpoint, define the maximum width of the container in a media query
+@mixin make-container-max-widths($max-widths: $container-max-widths, $breakpoints: $grid-breakpoints) {
+  @each $breakpoint, $container-max-width in $max-widths {
+    @include media-breakpoint-up($breakpoint, $breakpoints) {
+      width: $container-max-width;
+      max-width: 100%;
+    }
+  }
+}
+
+@mixin make-gutters($gutters: $grid-gutter-widths) {
+  @each $breakpoint in map-keys($gutters) {
+    @include media-breakpoint-up($breakpoint) {
+      $gutter: map-get($gutters, $breakpoint);
+      padding-right: ($gutter / 2);
+      padding-left:  ($gutter / 2);
+    }
+  }
+}
+
+@mixin make-row($gutters: $grid-gutter-widths) {
+  @if $enable-flex {
+    display: flex;
+    flex-wrap: wrap;
+  } @else {
+    @include clearfix();
+  }
+
+  @each $breakpoint in map-keys($gutters) {
+    @include media-breakpoint-up($breakpoint) {
+      $gutter: map-get($gutters, $breakpoint);
+      margin-right: ($gutter / -2);
+      margin-left:  ($gutter / -2);
+    }
+  }
+}
+
+@mixin make-col-ready($gutters: $grid-gutter-widths) {
+  position: relative;
+  min-height: 1px; // Prevent collapsing
+
+  // Prevent columns from becoming too narrow when at smaller grid tiers by
+  // always setting `width: 100%;`. This works because we use `flex` values
+  // later on to override this initial width.
+  @if $enable-flex {
+    width: 100%;
+  }
+
+  @each $breakpoint in map-keys($gutters) {
+    @include media-breakpoint-up($breakpoint) {
+      $gutter: map-get($gutters, $breakpoint);
+      padding-right: ($gutter / 2);
+      padding-left:  ($gutter / 2);
+    }
+  }
+}
+
+@mixin make-col($size, $columns: $grid-columns) {
+  @if $enable-flex {
+    flex: 0 0 percentage($size / $columns);
+    // Add a `max-width` to ensure content within each column does not blow out
+    // the width of the column. Applies to IE10+ and Firefox. Chrome and Safari
+    // do not appear to require this.
+    max-width: percentage($size / $columns);
+  } @else {
+    float: left;
+    width: percentage($size / $columns);
+  }
+}
+
+@mixin make-col-offset($size, $columns: $grid-columns) {
+  margin-left: percentage($size / $columns);
+}
+
+@mixin make-col-push($size, $columns: $grid-columns) {
+  left: if($size > 0, percentage($size / $columns), auto);
+}
+
+@mixin make-col-pull($size, $columns: $grid-columns) {
+  right: if($size > 0, percentage($size / $columns), auto);
+}
+
+@mixin make-col-modifier($type, $size, $columns) {
+  // Work around the lack of dynamic mixin @include support (https://github.com/sass/sass/issues/626)
+  @if $type == push {
+    @include make-col-push($size, $columns);
+  } @else if $type == pull {
+    @include make-col-pull($size, $columns);
+  } @else if $type == offset {
+    @include make-col-offset($size, $columns);
+  }
+}

bootstap 4 alpha 6/scss/mixins/_hover.scss

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+@mixin hover {
+  // TODO: re-enable along with mq4-hover-shim
+//  @if $enable-hover-media-query {
+//    // See Media Queries Level 4: https://drafts.csswg.org/mediaqueries/#hover
+//    // Currently shimmed by https://github.com/twbs/mq4-hover-shim
+//    @media (hover: hover) {
+//      &:hover { @content }
+//    }
+//  }
+//  @else {
+    &:hover { @content }
+//  }
+}
+
+@mixin hover-focus {
+  @if $enable-hover-media-query {
+    &:focus { @content }
+    @include hover { @content }
+  }
+  @else {
+    &:focus,
+    &:hover {
+      @content
+    }
+  }
+}
+
+@mixin plain-hover-focus {
+  @if $enable-hover-media-query {
+    &,
+    &:focus {
+      @content
+    }
+    @include hover { @content }
+  }
+  @else {
+    &,
+    &:focus,
+    &:hover {
+      @content
+    }
+  }
+}
+
+@mixin hover-focus-active {
+  @if $enable-hover-media-query {
+    &:focus,
+    &:active {
+      @content
+    }
+    @include hover { @content }
+  }
+  @else {
+    &:focus,
+    &:active,
+    &:hover {
+      @content
+    }
+  }
+}

bootstap 4 alpha 6/scss/mixins/_image.scss

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+// Image Mixins
+// - Responsive image
+// - Retina image
+
+
+// Responsive image
+//
+// Keep images from scaling beyond the width of their parents.
+
+@mixin img-fluid {
+  // Part 1: Set a maximum relative to the parent
+  max-width: 100%;
+  // Part 2: Override the height to auto, otherwise images will be stretched
+  // when setting a width and height attribute on the img element.
+  height: auto;
+}
+
+
+// Retina image
+//
+// Short retina mixin for setting background-image and -size.
+
+@mixin img-retina($file-1x, $file-2x, $width-1x, $height-1x) {
+  background-image: url($file-1x);
+
+  // Autoprefixer takes care of adding -webkit-min-device-pixel-ratio and -o-min-device-pixel-ratio,
+  // but doesn't convert dppx=>dpi.
+  // There's no such thing as unprefixed min-device-pixel-ratio since it's nonstandard.
+  // Compatibility info: http://caniuse.com/#feat=css-media-resolution
+  @media
+  only screen and (min-resolution: 192dpi), // IE9-11 don't support dppx
+  only screen and (min-resolution: 2dppx) { // Standardized
+    background-image: url($file-2x);
+    background-size: $width-1x $height-1x;
+  }
+}

bootstap 4 alpha 6/scss/mixins/_list-group.scss

@@ -0,0 +1,30 @@
+// List Groups
+
+@mixin list-group-item-variant($state, $background, $color) {
+  .list-group-item-#{$state} {
+    color: $color;
+    background-color: $background;
+  }
+
+  a.list-group-item-#{$state},
+  button.list-group-item-#{$state} {
+    color: $color;
+
+    .list-group-item-heading {
+      color: inherit;
+    }
+
+    @include hover-focus {
+      color: $color;
+      background-color: darken($background, 5%);
+    }
+
+    &.active {
+      @include plain-hover-focus {
+        color: #fff;
+        background-color: $color;
+        border-color: $color;
+      }
+    }
+  }
+}

bootstap 4 alpha 6/scss/mixins/_lists.scss

@@ -0,0 +1,7 @@
+// Lists
+
+// Unstyled keeps list items block level, just removes default browser padding and list-style
+@mixin list-unstyled {
+  padding-left: 0;
+  list-style: none;
+}

bootstap 4 alpha 6/scss/mixins/_nav-divider.scss

@@ -0,0 +1,10 @@
+// Horizontal dividers
+//
+// Dividers (basically an hr) within dropdowns and nav lists
+
+@mixin nav-divider($color: #e5e5e5) {
+  height: 1px;
+  margin: ($spacer-y / 2) 0;
+  overflow: hidden;
+  background-color: $color;
+}

bootstap 4 alpha 6/scss/mixins/_navbar-align.scss

@@ -0,0 +1,9 @@
+// Navbar vertical align
+//
+// Vertically center elements in the navbar.
+// Example: an element has a height of 30px, so write out `.navbar-vertical-align(30px);` to calculate the appropriate top margin.
+
+// @mixin navbar-vertical-align($element-height) {
+//   margin-top: (($navbar-height - $element-height) / 2);
+//   margin-bottom: (($navbar-height - $element-height) / 2);
+// }

bootstap 4 alpha 6/scss/mixins/_pagination.scss

@@ -0,0 +1,21 @@
+// Pagination
+
+@mixin pagination-size($padding-y, $padding-x, $font-size, $line-height, $border-radius) {
+  .page-link {
+    padding: $padding-y $padding-x;
+    font-size: $font-size;
+  }
+
+  .page-item {
+    &:first-child {
+      .page-link {
+        @include border-left-radius($border-radius);
+      }
+    }
+    &:last-child {
+      .page-link {
+        @include border-right-radius($border-radius);
+      }
+    }
+  }
+}

bootstap 4 alpha 6/scss/mixins/_progress.scss

@@ -0,0 +1,23 @@
+// Progress bars
+
+@mixin progress-variant($color) {
+  &[value]::-webkit-progress-value {
+    background-color: $color;
+  }
+
+  &[value]::-moz-progress-bar {
+    background-color: $color;
+  }
+
+  // IE10+, Microsoft Edge
+  &[value]::-ms-fill {
+    background-color: $color;
+  }
+
+  // IE9
+  @media screen and (min-width:0\0) {
+    .progress-bar {
+      background-color: $color;
+    }
+  }
+}

bootstap 4 alpha 6/scss/mixins/_reset-filter.scss

@@ -0,0 +1,8 @@
+// Reset filters for IE
+//
+// When you need to remove a gradient background, do not forget to use this to reset
+// the IE filter for IE9.
+
+@mixin reset-filter() {
+  filter: "progid:DXImageTransform.Microsoft.gradient(enabled = false)";
+}

bootstap 4 alpha 6/scss/mixins/_reset-text.scss

@@ -0,0 +1,17 @@
+@mixin reset-text {
+  font-family: $font-family-base;
+  // We deliberately do NOT reset font-size or word-wrap.
+  font-style: normal;
+  font-weight: normal;
+  letter-spacing: normal;
+  line-break: auto;
+  line-height: $line-height-base;
+  text-align: left; // Fallback for where `start` is not supported
+  text-align: start;
+  text-decoration: none;
+  text-shadow: none;
+  text-transform: none;
+  white-space: normal;
+  word-break: normal;
+  word-spacing: normal;
+}

bootstap 4 alpha 6/scss/mixins/_resize.scss

@@ -0,0 +1,6 @@
+// Resize anything
+
+@mixin resizable($direction) {
+  resize: $direction; // Options: horizontal, vertical, both
+  overflow: auto; // Per CSS3 UI, `resize` only applies when `overflow` isn't `visible`
+}

bootstap 4 alpha 6/scss/mixins/_screen-reader.scss

@@ -0,0 +1,32 @@
+// Only display content to screen readers
+//
+// See: http://a11yproject.com/posts/how-to-hide-content
+
+@mixin sr-only {
+  position: absolute;
+  width: 1px;
+  height: 1px;
+  padding: 0;
+  margin: -1px;
+  overflow: hidden;
+  clip: rect(0,0,0,0);
+  border: 0;
+}
+
+// Use in conjunction with .sr-only to only display content when it's focused.
+//
+// Useful for "Skip to main content" links; see https://www.w3.org/TR/2013/NOTE-WCAG20-TECHS-20130905/G1
+//
+// Credit: HTML5 Boilerplate
+
+@mixin sr-only-focusable {
+  &:active,
+  &:focus {
+    position: static;
+    width: auto;
+    height: auto;
+    margin: 0;
+    overflow: visible;
+    clip: auto;
+  }
+}

bootstap 4 alpha 6/scss/mixins/_size.scss

@@ -0,0 +1,6 @@
+// Sizing shortcuts
+
+@mixin size($width, $height: $width) {
+  width: $width;
+  height: $height;
+}

bootstap 4 alpha 6/scss/mixins/_tab-focus.scss

@@ -0,0 +1,9 @@
+// WebKit-style focus
+
+@mixin tab-focus() {
+  // WebKit-specific. Other browsers will keep their default outline style.
+  // (Initially tried to also force default via `outline: initial`,
+  // but that seems to erroneously remove the outline in Firefox altogether.)
+  outline: 5px auto -webkit-focus-ring-color;
+  outline-offset: -2px;
+}

bootstap 4 alpha 6/scss/mixins/_table-row.scss

@@ -0,0 +1,30 @@
+// Tables
+
+@mixin table-row-variant($state, $background) {
+  // Exact selectors below required to override `.table-striped` and prevent
+  // inheritance to nested tables.
+  .table-#{$state} {
+    &,
+    > th,
+    > td {
+      background-color: $background;
+    }
+  }
+
+  // Hover states for `.table-hover`
+  // Note: this is not available for cells or rows within `thead` or `tfoot`.
+  .table-hover {
+    $hover-background: darken($background, 5%);
+
+    .table-#{$state} {
+      @include hover {
+        background-color: $hover-background;
+
+        > td,
+        > th {
+          background-color: $hover-background;
+        }
+      }
+    }
+  }
+}

bootstap 4 alpha 6/scss/mixins/_tag.scss

@@ -0,0 +1,11 @@
+// Tags
+
+@mixin tag-variant($color) {
+  background-color: $color;
+
+  &[href] {
+    @include hover-focus {
+      background-color: darken($color, 10%);
+    }
+  }
+}

bootstap 4 alpha 6/scss/mixins/_text-emphasis.scss

@@ -0,0 +1,12 @@
+// Typography
+
+@mixin text-emphasis-variant($parent, $color) {
+  #{$parent} {
+    color: $color !important;
+  }
+  a#{$parent} {
+    @include hover-focus {
+      color: darken($color, 10%) !important;
+    }
+  }
+}

bootstap 4 alpha 6/scss/mixins/_text-hide.scss

@@ -0,0 +1,8 @@
+// CSS image replacement
+@mixin text-hide() {
+  font: 0/0 a;
+  color: transparent;
+  text-shadow: none;
+  background-color: transparent;
+  border: 0;
+}

bootstap 4 alpha 6/scss/mixins/_text-truncate.scss

@@ -0,0 +1,8 @@
+// Text truncate
+// Requires inline-block or block for proper styling
+
+@mixin text-truncate() {
+  overflow: hidden;
+  text-overflow: ellipsis;
+  white-space: nowrap;
+}