html, body {
    background-color: #000000;
    width: 100%;
    height: 100%;
    margin: 0;
    padding: 0;
}

html {}

body {
    background-repeat: no-repeat;
    background-position: center;
}

@media all and (max-height: 700px) {
    body {
        background-image: url('../images/shield_400.jpg');
    }
}

@media all {
    body {
        background-image: url('../images/shield_400.jpg');
    }
}