div[data-background-image] img {
    top: 0;
    left: 0;
    z-index: -1;
}

div[data-background-image-fond] img {
    position: fixed;
}

div[data-background-image-header] img {
    position: relative;
}

div[data-background-image-header] {
    position: absolute;
    z-index: -10;
}