.main-container {
    max-width: 1000px;
    margin: 0 auto;
    background: #eee;
}

.video-container {
    position: relative;
    padding-bottom: 56.25%;
    max-width: 940px;
    margin: 0 auto;
}

iframe {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
}