body, html 
{
    margin: 0;
    padding: 0;
}
div#main_menu
{
	position: absolute;
	left: 50%;
	margin-left: -450px;
}
iframe 
{
	position: absolute;
	top: 70px;
	left: 0px;
	width: 100%;
	height: 530px;
	overflow: hidden;
}