#train-transition-overlay {
    position: fixed; top: 0; left: 0;
    width: 100vw; height: 100vh;
    background: #000000;
    z-index: 99999;
    display: none; align-items: center; justify-content: center;
    pointer-events: none; opacity: 1;
}
#train-video {
    width: 100vw; height: 100vh;
    object-fit: cover; transform: scale(1.05);
}
#success-page {
    z-index: 2; 
    /* No opacity or transitions here. It will be handled via display property. */
}