refactor: rebuild .carousel-dark using CSS Variables

Author: mrholek

scss/_carousel.scss

@@ -98,15 +98,15 @@
   align-items: center; // 2. vertically center contents
   justify-content: center; // 3. horizontally center contents
   width: $carousel-control-width;
-  color: $carousel-control-color;
+  color: var(--#{$variable-prefix}carousel-control-color, $carousel-control-color);
   text-align: center;
   opacity: $carousel-control-opacity;
   @include transition($carousel-control-transition);
 
   // Hover/focus state
   &:hover,
   &:focus {
-    color: $carousel-control-color;
+    color: var(--#{$variable-prefix}carousel-control-color, $carousel-control-color);
     text-decoration: none;
     outline: 0;
     opacity: $carousel-control-hover-opacity;
@@ -175,7 +175,7 @@
     margin-left: $carousel-indicator-spacer;
     text-indent: -999px;
     cursor: pointer;
-    background-color: $carousel-indicator-active-bg;
+    background-color: var(--#{$variable-prefix}carousel-indicator-active-bg, $carousel-indicator-active-bg);
     background-clip: padding-box;
     // Use transparent borders to increase the hit area by 10px on top and bottom.
     border-top: $carousel-indicator-hit-area-height solid transparent;
@@ -201,23 +201,17 @@
   left: (100% - $carousel-caption-width) / 2;
   padding-top: $carousel-caption-padding-y;
   padding-bottom: $carousel-caption-padding-y;
-  color: $carousel-caption-color;
+  color: var(--#{$variable-prefix}carousel-caption-color, $carousel-caption-color);
   text-align: center;
 }
 
 // Dark mode carousel
 
 .carousel-dark {
+  --#{$variable-prefix}carousel-indicator-active-bg: #{$carousel-dark-indicator-active-bg};
+  --#{$variable-prefix}carousel-caption-color: #{$carousel-dark-caption-color};
   .carousel-control-prev-icon,
   .carousel-control-next-icon {
     filter: $carousel-dark-control-icon-filter;
   }
-
-  .carousel-indicators li {
-    background-color: $carousel-dark-indicator-active-bg;
-  }
-
-  .carousel-caption {
-    color: $carousel-dark-caption-color;
-  }
 }