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<html>
<head>
<style type="text/css">
.balken_yellow_preload {
height:20px;
width:20px;
overflow:hidden;
background: rgb(255,255,0);
transition: width .5s linear;
-moz-transition: width .5s linear; /* Firefox 4 */
-webkit-transition: width .5s linear; /* Safari and Chrome */
-o-transition: width .5s linear; /* Opera */
}
/* #balken_yellow:hover {
width:140px;
}*/
.balken_yellow_load {
height:20px;
width:140px;
overflow:hidden;
background: rgb(255,255,0);
transition: width .5s linear;
-moz-transition: width .5s linear; /* Firefox 4 */
-webkit-transition: width .5s linear; /* Safari and Chrome */
-o-transition: width .5s linear; /* Opera */
}
</style>
</head>
<body>
<div id="balken_yellow" class="balken_yellow_preload" onmouseover="this.style.width='140px'" onmouseout="this.style.width='10px'">Balken</div>
</body>
<script type="text/javascript">
//document.getElementById('balken_yellow').style.width='140px';
// (geht im FF 16 nur ohne Transition)
//document.getElementById('balken_yellow').setAttribute('class','balken_yellow_load');
// (geht im FF 16 nur ohne Transition)
</script>
</html>