feat(standard-styling): Add button color map

falcon/_dev/css/theme/custom/abstracts/_mixins.scss

@@ -0,0 +1,73 @@
+// Bootstrap 5-style responsive mixins (more intuitive than Bootstrap 4)
+// Learn the difference here https://getbootstrap.com/docs/5.0/migration/#sass
+
+@mixin bs5-media-breakpoint-up($name) {
+    $min: map-get($grid-breakpoints, $name);
+    @if $min and $min > 0 {
+        @media (min-width: $min) {
+            @content;
+        }
+    } @else {
+        @content;
+    }
+}
+
+@mixin bs5-media-breakpoint-down($name) {
+    $max: map-get($grid-breakpoints, $name);
+    @if $max {
+        @media (max-width: calc(#{$max} - 0.02px)) {
+            @content;
+        }
+    } @else {
+        @content;
+    }
+}
+
+@mixin bs5-media-breakpoint-between($lower, $upper) {
+    $min: map-get($grid-breakpoints, $lower);
+    $max: map-get($grid-breakpoints, $upper);
+    @if $min and $max {
+        @media (min-width: $min) and (max-width: calc(#{$max} - 0.02px)) {
+            @content;
+        }
+    }
+}
+
+@mixin bs5-media-breakpoint-only($name) {
+    $breakpoint-names: map-keys($grid-breakpoints);
+    $index: index($breakpoint-names, $name);
+    $next-name: nth($breakpoint-names, $index + 1);
+
+    @include bs5-media-breakpoint-between($name, $next-name) {
+        @content;
+    }
+}
+
+// Mixin to add an after pseudo-element with a mask image to customize button colors
+/* Example: 
+
+.btn-arrow-right{
+    &::after {
+        @include btn-after("../img/arrow-right.svg");
+    }
+}
+    
+*/
+
+@mixin btn-after($url, $color: currentColor) {
+    content: "";
+    display: inline-block;
+    width: 1em;
+    height: 1em;
+    margin-left: 0.5em;
+    vertical-align: middle;
+    background-color: currentColor;
+    mask-image: url(#{$url});
+    mask-size: contain;
+    mask-repeat: no-repeat;
+    mask-position: center;
+    -webkit-mask-image: url(#{$url});
+    -webkit-mask-size: contain;
+    -webkit-mask-repeat: no-repeat;
+    -webkit-mask-position: center;
+}