为什么清除了浮动 foot还是没有显示
<style type="text/css">
body{ margin:0; padding:0; font-size:30px; color:#fff}
.top{width:100%; background:gray;}
.main{ width:100%; height:300px; background:red;}
.right{margin-left:210px;width:100%;height:300px;background:green;position:absolute;}
.left{ width:200px; height:300px; background:blue; position:absolute; }
}
.foot{width:100%; height:50px;background:#369; clear:both;}
