diff --git a/framework/core/js/src/common/utils/isDark.ts b/framework/core/js/src/common/utils/isDark.ts
index f12ac2cdf..03755a8e8 100644
--- a/framework/core/js/src/common/utils/isDark.ts
+++ b/framework/core/js/src/common/utils/isDark.ts
@@ -6,8 +6,7 @@
  */
 
 export default function isDark(hexcolor: String) {
-
-  var hexnumbers = hexcolor.replace("#", "");
+  let hexnumbers = hexcolor.replace("#", "");
 
   if (hexnumbers.length == 3) {
     hexnumbers += hexnumbers;