diff --git a/plugins/convertColors.js b/plugins/convertColors.js
index c723d4c38..8a91b8d98 100644
--- a/plugins/convertColors.js
+++ b/plugins/convertColors.js
@@ -19,7 +19,7 @@ var collections = require('./_collections'),
     rComma = '\\s*,\\s*',
     regRGB = new RegExp('^rgb\\(\\s*' + rNumber + rComma + rNumber + rComma + rNumber + '\\s*\\)$'),
     regHEX = /^\#(([a-fA-F0-9])\2){3}$/,
-    none = /none/i;
+    none = /\bnone\b/i;
 
 /**
  * Convert different colors formats in element attributes to hex.