.video-wrapper {
    position: relative;
    width: 100%;
    max-width: 960px;   /* optional: limits size on desktop */
    margin: 0 auto;     /* centers video */
    aspect-ratio: 16 / 9;
}

.video-wrapper iframe {
    width: 100%;
    height: 100%;
    border: 0;
}

@media (max-width: 600px) {
    .video-wrapper {
        max-width: 100%;
    }
}