Tryit Editor v1.8

Source Code:

<!DOCTYPE html>
<html>
<head>
<style> 
div
{
width:100px;
height:100px;
background:red;
position:relative;
animation:mymove 5s infinite;
-webkit-animation:mymove 5s infinite; /* Safari and Chrome */
}

@keyframes mymove
{
0%   {top:0px; background:red; width:100px;}
100% {top:200px; background:yellow; width:300px;}
}

@-webkit-keyframes mymove /* Safari and Chrome */
{
0%   {top:0px; background:red; width:100px;}
100% {top:200px; background:yellow; width:300px;}
}
</style>
</head>
<body>

<p><strong>Note:</strong> The @keyframes rule is not supported in Internet Explorer 9 and earlier versions.</p>

<div></div>

</body>
</html>

Result:

W3Schools.com - Try it yourself

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