清除浮动的几种方法

.clear{zoom:1;}
	.clear:after{
		content: "";
		display: block;
		clear: both;
	}


	.clearfloat:after{
		display:block;
		clear:both;content:"";
		visibility:hidden;
		height:0
	}
	.clearfloat{zoom:1
	}
	.clear{
		clear:both;
		zoom:1;
	}