<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width,initial-scale=1 user-scalable=0">
<title>Document</title>
<style>
* {
padding: 0;
margin: 0;
}
.one {
20%;
height: 100px;
float: left;
background: red;
}
.two {
30%;
height: 100px;
float: left;
background: blue;
}
.three {
50%;
height: 100px;
float: left;
background: green;
}
.four {
50%;
height: 50%;
background: #fff;
}
</style>
</head>
<body>
<div class="one"></div>
<div class="two"></div>
<div class="three">
<div class="four"></div>
</div>
</body>
</html>