diff --git modules/system/system.base.css modules/system/system.base.css
index a6748de..b7eff49 100644
--- modules/system/system.base.css
+++ modules/system/system.base.css
@@ -244,21 +244,24 @@ html.js .js-hide {
 /**
  * Markup free clearing.
  *
- * @see http://perishablepress.com/press/2009/12/06/new-clearfix-hack
+ * @see http://www.yuiblog.com/blog/2010/09/27/clearfix-reloaded-overflowhidden-demystified/
+ * @see http://blueprintcss.lighthouseapp.com/projects/15318/tickets/5-extra-margin-padding-bottom-of-page
  */
+.clearfix:before,
 .clearfix:after {
-  content: ".";
+  content: "\0020";
   display: block;
   height: 0;
-  clear: both;
   visibility: hidden;
 }
+.clearfix:after {
+  clear: both;
+}
 /* IE6 */
 * html .clearfix {
-  height: 1%;
+  zoom: 1;
 }
 /* IE7 */
 *:first-child + html .clearfix {
-  min-height: 1%;
+  zoom: 1;
 }
-