hsla instead of HEX for alpha

Author: FromEndWorld

_sass/_variables.scss

@@ -38,7 +38,7 @@ $base-lighten-color: $oc-gray-6;
 $base-lightener-color: $oc-gray-4;
 
 $background-color: $oc-gray-0;
-$background-lighten-color: #f8f9fa6b;
+$background-lighten-color: hsla(210, 17%, 98%, 0.42);
 
 $text-color: $base-color;
 $link-color: $oc-teal-8;
@@ -61,7 +61,7 @@ $footnote-link-background-over-color: $oc-gray-1;
 $selection-background-color: $oc-gray-3;
 
 $tag-index-label-background-color: $oc-gray-2;
-$tag-index-count-background-color: #868e961a;
+$tag-index-count-background-color: hsla(210, 7%, 56%, 0.102);
 
 $footer-border-color: $oc-gray-2;
 $footer-background-color: $oc-gray-0;