<!DOCTYPE html>
<html>
<head>
<style type='text/css'>
html, body {
height: 100%;
width: 100%;
}
.col1 {
width: 50%;
height: 100%;
background: #666;
float: left;
}
.col2, .col3 {
width: 50%;
height: 50%;
background: #333;
float: left;
}
.col3 {
background: #999;
}
</style>
</head>
<body>
<div class="col1">column 01</div>
<div class="col2">column 02</div>
<div class="col3">column 03</div>
</body>
</html>