diff --git a/lib/ace/mode/css_highlight_rules.js b/lib/ace/mode/css_highlight_rules.js
index 3a8780d9..da91a515 100644
--- a/lib/ace/mode/css_highlight_rules.js
+++ b/lib/ace/mode/css_highlight_rules.js
@@ -76,7 +76,7 @@ var CssHighlightRules = function() {
             token : ["constant.numeric", "keyword"],
             regex : "(" + numRe + ")(ch|cm|deg|em|ex|fr|gd|grad|Hz|in|kHz|mm|ms|pc|pt|px|rad|rem|s|turn|vh|vm|vw|%)"
         }, {
-            token : ["constant.numeric"],
+            token : "constant.numeric",
             regex : numRe
         }, {
             token : "constant.numeric",  // hex6 color