body{ margin:0; padding:0; font-size:30px; color:#fff}
.top{height:100px;background:#ccc;}
.main{background:red;}
.left{ height:400px;;width:200px;background:#123;position:absolute;top:100px;left:0;}
.right{height:400px;background:#789;margin-left:210px;}
.foot{height:100px;background:yellow;}
