body {
    font-family: Arial, sans-serif;
    margin: 0;
    background: #f4f4f4;
    color: #222;
}

header {
    background: #222;
    color: white;
    padding: 2rem;
    text-align: center;
}

main {
    padding: 2rem;
}

button {
    padding: 0.7rem 1.2rem;
    font-size: 1rem;
    cursor: pointer;
}

.video-wrapper {
    position: relative;
    width: 100%;
    max-width: 800px;   /* optional, wirkt hochwertiger */
    margin: 2rem auto; /* zentriert */
    padding-top: 56.25%; /* 16:9 Verhältnis */
}

.video-wrapper iframe {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    border: 0;
}