diff --git modules/system/system.base.css modules/system/system.base.css
index 29063ca..60c54c1 100644
--- modules/system/system.base.css
+++ modules/system/system.base.css
@@ -248,7 +248,7 @@ html.js .js-hide {
  * @see http://perishablepress.com/press/2009/12/06/new-clearfix-hack
  */
 .clearfix:after {
-  content: ".";
+  content: "\0020";
   display: block;
   height: 0;
   clear: both;