<section class="wrap">
  <div class="video-bg">
    <iframe src="https://www.youtube.com/embed/Xe62J2ca87c?autoplay=1&mute=1&playsinline=1&loop=1&playlist=Xe62J2ca87c&controls=0&disablekb=1" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>
  </div>
  <div class="content">
    <div class="container">
      <h1 class="title">
        YouTube Embed Background without JS
      </h1>
    </div>
  </div>
</section>

html, body {
  margin: 0;
  padding: 0;
}

.wrap {
  position: relative;
  height: 100vh;
}

.video-bg {
  position: relative;
  height: 100%;
  background: #000;
  overflow: hidden;
}

.video-bg::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  display: block;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, .3);
  background-image: url("data:image/svg+xml,%3Csvg width='6' height='6' viewBox='0 0 6 6' xmlns='http://www.w3.org/2000/svg'%3E%3Cg fill='%23000000' fill-opacity='0.4' fill-rule='evenodd'%3E%3Cpath d='M5 0h1L0 6V5zM6 5v1H5z'/%3E%3C/g%3E%3C/svg%3E");
}

.video-bg iframe {
  display: block;
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 100vw;
  height: 60vw;
}

.content {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  color: #fff;
}

.container {
  position: absolute;
  top: 50%;
  left: 50%;
  width: 100%;
  transform: translate(-50%, -50%);
}

.title {
  text-align: center;
  font-size: 2.5vw;
}