#front {
    display: block;
}

#mainImg {
    display: none;
}

#front::before {
    content: "";
    background-image: url("../Assets/bg.jpg");
    background-repeat: no-repeat;
    position: absolute;
    top: 0;
    left: 0;
    padding-top: calc(100% / 16 * 9); /* 16:9 aspect ratio */
    width: 100%;
    z-index: -1;
    opacity: 0.9;
}

#intro {
    text-align: center;
    margin: 13rem 0;
}