.background{
    z-index: -1;
}

/* ============================================================
   DESKTOP (min-width: 780px)
   ============================================================ */

@media screen and (min-width: 780px) {
    .background {
        position: fixed;
        top: 0;
        left: 0;
        width: 100%;
        height: 100%;

    }

    .background img {
        width: 100%;
        height: 110%;
        object-fit: cover;
    }
}

/* ============================================================
   MOBILE (max-width: 780px)
   ============================================================ */

@media screen and (max-width: 780px) {
    .background {
    position: relative;
    }

    .background img {
        object-fit: cover;
    }
}