diff --git a/static/bootstrap/stylesheets/bootstrap/mixins/_vendor-prefixes.scss b/static/bootstrap/stylesheets/bootstrap/mixins/_vendor-prefixes.scss
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+// Vendor Prefixes
+//
+// All vendor mixins are deprecated as of v3.2.0 due to the introduction of
+// Autoprefixer in our Gruntfile. They have been removed in v4.
+
+// - Animations
+// - Backface visibility
+// - Box shadow
+// - Box sizing
+// - Content columns
+// - Hyphens
+// - Placeholder text
+// - Transformations
+// - Transitions
+// - User Select
+
+
+// Animations
+@mixin animation($animation) {
+  -webkit-animation: $animation;
+       -o-animation: $animation;
+          animation: $animation;
+}
+@mixin animation-name($name) {
+  -webkit-animation-name: $name;
+          animation-name: $name;
+}
+@mixin animation-duration($duration) {
+  -webkit-animation-duration: $duration;
+          animation-duration: $duration;
+}
+@mixin animation-timing-function($timing-function) {
+  -webkit-animation-timing-function: $timing-function;
+          animation-timing-function: $timing-function;
+}
+@mixin animation-delay($delay) {
+  -webkit-animation-delay: $delay;
+          animation-delay: $delay;
+}
+@mixin animation-iteration-count($iteration-count) {
+  -webkit-animation-iteration-count: $iteration-count;
+          animation-iteration-count: $iteration-count;
+}
+@mixin animation-direction($direction) {
+  -webkit-animation-direction: $direction;
+          animation-direction: $direction;
+}
+@mixin animation-fill-mode($fill-mode) {
+  -webkit-animation-fill-mode: $fill-mode;
+          animation-fill-mode: $fill-mode;
+}
+
+// Backface visibility
+// Prevent browsers from flickering when using CSS 3D transforms.
+// Default value is `visible`, but can be changed to `hidden`
+
+@mixin backface-visibility($visibility) {
+  -webkit-backface-visibility: $visibility;
+     -moz-backface-visibility: $visibility;
+          backface-visibility: $visibility;
+}
+
+// Drop shadows
+//
+// Note: Deprecated `.box-shadow()` as of v3.1.0 since all of Bootstrap's
+// supported browsers that have box shadow capabilities now support it.
+
+@mixin box-shadow($shadow...) {
+  -webkit-box-shadow: $shadow; // iOS <4.3 & Android <4.1
+          box-shadow: $shadow;
+}
+
+// Box sizing
+@mixin box-sizing($boxmodel) {
+  -webkit-box-sizing: $boxmodel;
+     -moz-box-sizing: $boxmodel;
+          box-sizing: $boxmodel;
+}
+
+// CSS3 Content Columns
+@mixin content-columns($column-count, $column-gap: $grid-gutter-width) {
+  -webkit-column-count: $column-count;
+     -moz-column-count: $column-count;
+          column-count: $column-count;
+  -webkit-column-gap: $column-gap;
+     -moz-column-gap: $column-gap;
+          column-gap: $column-gap;
+}
+
+// Optional hyphenation
+@mixin hyphens($mode: auto) {
+  word-wrap: break-word;
+  -webkit-hyphens: $mode;
+     -moz-hyphens: $mode;
+      -ms-hyphens: $mode; // IE10+
+       -o-hyphens: $mode;
+          hyphens: $mode;
+}
+
+// Placeholder text
+@mixin placeholder($color: $input-color-placeholder) {
+  // Firefox
+  &::-moz-placeholder {
+    color: $color;
+    opacity: 1; // Override Firefox's unusual default opacity; see https://github.com/twbs/bootstrap/pull/11526
+  }
+  &:-ms-input-placeholder { color: $color; } // Internet Explorer 10+
+  &::-webkit-input-placeholder  { color: $color; } // Safari and Chrome
+}
+
+// Transformations
+@mixin scale($ratio...) {
+  -webkit-transform: scale($ratio);
+      -ms-transform: scale($ratio); // IE9 only
+       -o-transform: scale($ratio);
+          transform: scale($ratio);
+}
+
+@mixin scaleX($ratio) {
+  -webkit-transform: scaleX($ratio);
+      -ms-transform: scaleX($ratio); // IE9 only
+       -o-transform: scaleX($ratio);
+          transform: scaleX($ratio);
+}
+@mixin scaleY($ratio) {
+  -webkit-transform: scaleY($ratio);
+      -ms-transform: scaleY($ratio); // IE9 only
+       -o-transform: scaleY($ratio);
+          transform: scaleY($ratio);
+}
+@mixin skew($x, $y) {
+  -webkit-transform: skewX($x) skewY($y);
+      -ms-transform: skewX($x) skewY($y); // See https://github.com/twbs/bootstrap/issues/4885; IE9+
+       -o-transform: skewX($x) skewY($y);
+          transform: skewX($x) skewY($y);
+}
+@mixin translate($x, $y) {
+  -webkit-transform: translate($x, $y);
+      -ms-transform: translate($x, $y); // IE9 only
+       -o-transform: translate($x, $y);
+          transform: translate($x, $y);
+}
+@mixin translate3d($x, $y, $z) {
+  -webkit-transform: translate3d($x, $y, $z);
+          transform: translate3d($x, $y, $z);
+}
+@mixin rotate($degrees) {
+  -webkit-transform: rotate($degrees);
+      -ms-transform: rotate($degrees); // IE9 only
+       -o-transform: rotate($degrees);
+          transform: rotate($degrees);
+}
+@mixin rotateX($degrees) {
+  -webkit-transform: rotateX($degrees);
+      -ms-transform: rotateX($degrees); // IE9 only
+       -o-transform: rotateX($degrees);
+          transform: rotateX($degrees);
+}
+@mixin rotateY($degrees) {
+  -webkit-transform: rotateY($degrees);
+      -ms-transform: rotateY($degrees); // IE9 only
+       -o-transform: rotateY($degrees);
+          transform: rotateY($degrees);
+}
+@mixin perspective($perspective) {
+  -webkit-perspective: $perspective;
+     -moz-perspective: $perspective;
+          perspective: $perspective;
+}
+@mixin perspective-origin($perspective) {
+  -webkit-perspective-origin: $perspective;
+     -moz-perspective-origin: $perspective;
+          perspective-origin: $perspective;
+}
+@mixin transform-origin($origin) {
+  -webkit-transform-origin: $origin;
+     -moz-transform-origin: $origin;
+      -ms-transform-origin: $origin; // IE9 only
+          transform-origin: $origin;
+}
+
+
+// Transitions
+
+@mixin transition($transition...) {
+  -webkit-transition: $transition;
+       -o-transition: $transition;
+          transition: $transition;
+}
+@mixin transition-property($transition-property...) {
+  -webkit-transition-property: $transition-property;
+          transition-property: $transition-property;
+}
+@mixin transition-delay($transition-delay) {
+  -webkit-transition-delay: $transition-delay;
+          transition-delay: $transition-delay;
+}
+@mixin transition-duration($transition-duration...) {
+  -webkit-transition-duration: $transition-duration;
+          transition-duration: $transition-duration;
+}
+@mixin transition-timing-function($timing-function) {
+  -webkit-transition-timing-function: $timing-function;
+          transition-timing-function: $timing-function;
+}
+@mixin transition-transform($transition...) {
+  -webkit-transition: -webkit-transform $transition;
+     -moz-transition: -moz-transform $transition;
+       -o-transition: -o-transform $transition;
+          transition: transform $transition;
+}
+
+
+// User select
+// For selecting text on the page
+
+@mixin user-select($select) {
+  -webkit-user-select: $select;
+     -moz-user-select: $select;
+      -ms-user-select: $select; // IE10+
+          user-select: $select;
+}