<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
<style type="text/css">
.co {
width: 100%;
background-color: aqua;
float: left;
}
.main{
margin-left: 200px;
}
.left {
width: 200px;
background-color: bisque;
float: left;
margin-left: -100%;
}
.right {
width: 300px;
background-color: greenyellow;
float: left;
margin-left: -300px;
}
</style>
</head>
<body>
<div class="contain">
<div class="co">
<div class="main">main</div>
</div>
<div class="left">left</div>
<div class="right">right</div>
</div>
</body>
</html>
