test_position.html

<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<style type="text/css">
		*{
			margin: 0;
			padding: 0;
			border: 0;
			outline: 0;
		}
		div{
			font-size: 0;
		}
		.red{
			width: 200px;
			height: 200px;
			background-color: red;
		}
		.green{
			width: 80px;
			height: 80px;
			background-color: green;
		}
		.yellow{
			width: 50px;
			height: 50px;
			background-color: yellow;
			display: inline-block;
			vertical-align: top;
		}
		.blue{
			width: 70px;
			height: 70px;
			background-color: blue;
			display: inline-block;
		}
	</style>
	<title>test_position</title>
</head>
<body>
<div class="container">
	<div class="red">
		<div class="yellow"></div>
		<div class="blue"></div>
	</div>
	<div class="green"></div>
</div>	
</body>
</html>