/* Desktop default */
#main-hero.parallax-bg {
    background-image: url('../images/back-new.jpg');
    background-size: cover;
    background-position: center;
}

/* Mobile için */
@media (max-width: 768px) {
    #main-hero.parallax-bg {
        background-image: url('../images/back-new-mobile.jpg');
    }
}