<!DOCTYPE html>
<html lang="en-US">
<head>
<style>
div{
width:100px;
height:100px;
background:green;
border:1px solid #000;
animation: myAnimation 5s infinite;
-webkit-animation: myAnimation 5s infinite; /* Safari 4.0 - 8.0 */
}
@keyframes myAnimation {
50% {
width:200px;
}
}
/* Safari 4.0 - 8.0 */
@-webkit-keyframes myAnimation {
50% {
width:200px;
}
}
</style>
</head>
<body>
<h1>CSS Animatable width</h1>
<div></div> </body>
</html>