img.bg {
    min-height:100%;
    min-width:1024px;
    width:100%;
    height:auto;
    position:fixed;
    top:0;
    left:0;
}

@media screen and (max-width: 1024px) {
    img.bg {
        left:50%;
        margin-left:-512px;
    }
}

body {
    margin: 0px;
}