<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<style>
.wrapper > div{height:50px float:left;}
.left{width:100%; background-color: #f00;}
.midd{width:50%; background-color: #0f0;}
.right{width:50%; background-color: #00f;}
</style>
</head>
<body>
<div class=wrapper>
<div class=left></div>
<div class=midd></div>
<div class=right></div>
</div>
</body>
</html>