body,html {
    height:100%;
    min-height:100%;
}

body {
    background:url(background.jpg) center center no-repeat #000;
}

div#centerContent {
    width:1018px;
    height:618px;
    position:relative;
    top:50%;
    left:50%;
    margin-left:-509px;
    margin-top:-309px;
}