1
.clearfix:after{content:".";display:block;height:0;clear:both;visibility:hidden} .clearfix{*+height:1%;}
2
.clearfix{overflow:auto;_height:1%}
3
.clearfix{overflow:hidden;_zoom:1;}
浮动闭合方案：clearfix
原文：http://www.cnblogs.com/DajiangDev/p/3525795.html
