<!DOCTYPE html>
<html>
<head>
<style>
#main {
width: 350px;
height: 100px;
border: 1px solid #c3c3c3;
display: -webkit-flex; /* Safari */
display: flex;
}
/* Safari 6.1+ */
#main div:nth-of-type(1) {-webkit-flex-grow: 1;}
#main div:nth-of-type(2) {-webkit-flex-grow: 1;}
#main div:nth-of-type(3) {-webkit-flex-grow: 1;}
/* Standard syntax */
#main div:nth-of-type(1) {flex-grow: 1;}
#main div:nth-of-type(2) {flex-grow: 1;}
#main div:nth-of-type(3) {flex-grow: 1;}
</style>
</head>
<body>
<div id="main">
<div style="background-color:coral;"></div>
<div style="background-color:lightblue;" id="myBlueDiv"></div>
<div style="background-color:khaki;"></div>
</div>
<p>Click the "Try it" button to set the value of the flexGrow property to "5" for the blue div element</p>
<button onclick="myFunction()">Try it</button>
<p><b>Note:</b> Internet Explorer 10 and earlier versions earlier versions do not support the flexGrow property.</p>
<p><b>Note:</b> Safari 6.1 (and newer) supports an alternative, the WebkitFlexGrow property.</p>
<script>
function myFunction() {
document.getElementById("myBlueDiv").style.WebkitFlexGrow = "5"; // Safari 6.1+
document.getElementById("myBlueDiv").style.flexGrow = "5";
}
</script>
</body>
</html>