CSS 父级伪类清除浮动

.clearfix:after {
  content: "";
  display: block;
  hight: 0;
  visibility: hidden;
  clear: both;
}
.clearfix {
  *zoom: 1; //IE 6,7 清除浮动
}

.clearfix:before,
.clearfix:after {
  content: "";
  display: table;
}
.clearfix:after {
  clear:both;
}
.clearfix {
  *zoom: 1;
}