<!DOCTYPE html>
<html>
<head>
<title>CSS Flexible Box Test: display proprety - flex</title>
<link rel="author" title="haosdent" href="mailto:haosdent@gmail.com">
<style type="text/css">
.container {
position: relative;
height: 6em;
width: 3em;
background: red;
margin: 1em;
border: 1px solid black;
}
.success {
background: green;
width: 100%;
height: 100%;
display: block;
}
</style>
</head>
<body>
<p>The test passed if you can't find red color.</p>
<div class="container">
<span class="success">Hello</span>
</div>
</body>
</html>