body { width: 100%; height: 100%; padding: 0; }

div {
    position: absolute;
    height: 100%;
    width: 100%;
    display: table;
    top: -5px;
    left: -5px;
}

h1 {
    display: table-cell;
    vertical-align: middle;
    text-align: center;
    background: url('hesse-wappen.png') no-repeat center center;
}