#illuminate-img {
    position: fixed;
    z-index: 3;

    /* CSS trick to center and maintain aspect ratio in most situations */
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
}

#illuminate-highres-img {
    display: none;
}

#illuminate-blackout {
    position: fixed;
    top: 0px;
    left: 0px;
    width: 100%;
    height: 100%;
    background-color: black;
    z-index: 2;
    opacity: 0.85;
}