#main {
	position:absolute;
	top: 50%;
	left: 50%;
	width:770px;
	height:480px;
	margin-left: -385px; /*set to a negative number 1/2 of your width*/
	margin-top: -240px; /*set to a negative number 1/2 of your height*/
	/*border: 1px solid;*/
	background-color: #ffffff;
	overflow: hidden;
}