Tryit Editor v2.9

Edit This Code:
<!DOCTYPE html>
<html>
<head>
<style> 
div {
    width: 100px;
    height: 100px;
    background: red;
    -webkit-transition-property: width; /* Safari */
    -webkit-transition-duration: 2s; /* Safari */
    transition-property: width;
    transition-duration: 2s;
}

div:hover {
    width: 300px;
}
</style>
</head>
<body>

<p><b>Note:</b> This example does not work in Internet Explorer 9 and earlier versions.</p>

<div></div>

<p>Hover over the div element above, to see the transition effect.</p>

</body>
</html>