<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>Document</title>
<style>
html,body{
height:100%;
}
.content{
height:100%;
background-color: red;
position: relative;
z-index: -3
}
.right_top{
height:400px;
300px;
background: yellow;
z-index: 1
}
.right_bottom{
height:100%;
background-color: violet;
300px;
position: absolute;
right: 0;
top: 0;
z-index: -1
}
.l{
float: right;
}
.r{
height: 100%; 400px;float: left;
background: wheat;
}
</style>
</head>
<body>
<div class="content">
<div class="r"></div>
<div class="l">
<div class="right_top"></div>
</div>
<div class="right_bottom"></div>
</div>
</body>
<script>
</script>
</html>