body {
    margin: 0;
    padding: 0;
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    background-color: black;
    transition: background 3s ease-in-out;
}

.relaxing {
    background-color: black;
}

.relaxing video {
    opacity: 1;
    visibility: visible;
    transition: opacity 3s ease-in-out, visibility 3s ease-in-out;
}

.blackout {
    background-color: black;
}

.blackout video {
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.3s ease-in-out, visibility 0.3s ease-in-out;
}

video {
    position: absolute;
    width: 100%;
    height: 100%;
    object-fit: cover;
}