.top{background:gray;
height:150px;
}
.main{background:red;
height:700px;
}
.left{
position:absolute;
top:150px;
left:0px;
background:blue;
height:700px;
width:200px;
}
.right{background:green;
height:700px;
margin-left:210px;
}
.foot{background:orange;
h