Add missing color variablef

src/themes/default/globals/site.variables

@@ -178,13 +178,14 @@
      Alpha Colors
 --------------------*/
 
-@subtleTransparentBlack : rgba(0, 0, 0, 0.03);
-@transparentBlack       : rgba(0, 0, 0, 0.05);
-@strongTransparentBlack : rgba(0, 0, 0, 0.10);
-
-@subtleTransparentWhite : rgba(255, 255, 255, 0.02);
-@transparentWhite       : rgba(255, 255, 255, 0.08);
-@strongTransparentWhite : rgba(255, 255, 255, 0.15);
+@subtleTransparentBlack     : rgba(0, 0, 0, 0.03);
+@transparentBlack           : rgba(0, 0, 0, 0.05);
+@strongTransparentBlack     : rgba(0, 0, 0, 0.10);
+@veryStrongTransparentBlack : rgba(0, 0, 0, 0.15);
+
+@subtleTransparentWhite     : rgba(255, 255, 255, 0.02);
+@transparentWhite           : rgba(255, 255, 255, 0.08);
+@strongTransparentWhite     : rgba(255, 255, 255, 0.15);
 
 /*-------------------
        Accents