animation

animation

hi to all.
i facing small problem in animation this is my example
<html>
<head>
<style>
#mydiv
{
border: 1px solid green;
background-color: lime;
height: 46px;
width: 121px;
}
</style>
<script>
$(document).ready(function(){
$("#mydiv").click(function()
{
$(this).animate({height:"300px",width:"200px",'backgroundColor':'red'});
});
});

</script>
</head>
<body>
<div id="mydiv">
hi this is inside div
</div>
</body>
</html>

when ever click on my div  height and width is changed but the background color is not changed.
i tried background-color:"red" also.