.banner-image {
    background-position: center center;
    background-repeat: no-repeat;
    background-size: cover;
    background-attachment: fixed;
}

/* Default (Desktop) */
.banner-image.desktop {
    display: block;
}

.banner-image.mobile {
    display: none !important;
}

/* Mobile (max-width: 767px) */
@media (max-width: 767px) {
    .banner-image.desktop {
        display: none !important;
    }

    .banner-image.mobile {
        display: block !important;
    }
}