html, body {
    margin: 0;
    padding: 0;
    overflow: hidden;
    height: 100%;
    background: black;
}

#background-video {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    /* We'll apply object-fit transitions via JS for precise timing */
}