Customizable table group seperator colors

scss/_tables.scss

@@ -41,7 +41,7 @@
   // Highlight border color between thead, tbody and tfoot.
   // stylelint-disable-next-line selector-max-universal
   > :not(:last-child) > :last-child > * {
-    border-bottom-color: currentColor;
+    border-bottom-color: $table-group-seperator-color;
   }
 }
 

scss/_variables.scss

@@ -492,6 +492,8 @@ $table-border-color:          $border-color !default;
 
 $table-striped-order:         odd !default;
 
+$table-group-seperator-color: currentColor !default;
+
 $table-caption-color:         $text-muted !default;
 
 $table-bg-level:              -9 !default;