body { background-color:#fff; margin:0; }

#main_container
{
	position:absolute;
	top:50%;
	left:50%;
	margin:0 auto;
	text-align:left;
	margin-top:-344px;
	margin-left:-650px;
	background:url('img/baustelle.jpg');
	width:1300px;
	height:688px;
}