html,body{
	height:100%; /* necessary to get the background image centered in the viewport */
	margin:0;
	padding:0;
}
#vcenter{
	float:left; /* let it float */
	width:100%; /* a float needs a width */
	height:50%; /* make this element as high as 50% of the page */
	margin-top:-330px; /* drag the element upward half the height of the #hcenter element to vertical center it */
}
#hcenter {
	clear:both; /* to clear the float element: #vcenter */
	width:995px; /* the width of the element that contains the site */
	height:660px; /* the height of the element that contains the site, margin-top of #vcenter should be half this value */
	margin:0 auto; /* center this element horizontal*/
	overflow:auto; /* allow content to scroll inside element */
}