<!DOCTYPE html>
<html>
<head>
<style>
#main {
width: 220px;
height: 300px;
border: 1px solid black;
display: -webkit-flex; /* Safari */
display: flex;
}
#main div {
-webkit-flex: 1; /* Safari 6.1+ */
-ms-flex: 1; /* IE 10 */
flex: 1;
}
</style>
</head>
<body>
<div id="main">
<div style="background-color:coral;">RED</div>
<div style="background-color:lightblue;">BLUE</div>
<div style="background-color:lightgreen;">Green div with more content.</div>
</div>
<p><b>Note:</b> Internet Explorer 9 and earlier versions do not support the flex property.</p>
<p><b>Note:</b> Internet Explorer 10 supports an alternative, the -ms-flex property. IE11 and newer versions fully support the flex property (do not need the -ms- prefix).</p>
<p><b>Note:</b> Safari 6.1 (and newer) supports an alternative, the -webkit-flex property.</p>
</body>
</html>