YouTube Player APIを使用して埋め込んだYouTube動画の速度を指定して再生開始させる方法（iframeタグを使用）のデモページ

.wrap {
  width: 630px;
  margin: 50px auto 0;
}

.movie {
  position: relative;
  width: 100%;
  padding-top: 56.25%;
}

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

@media screen and (max-width:640px) {
  .wrap {
    width: 100%;
  }
}
  

var tag = document.createElement('script');
tag.src = "https://www.youtube.com/iframe_api";
var firstScriptTag = document.getElementsByTagName('script')[0];
firstScriptTag.parentNode.insertBefore(tag, firstScriptTag);
var player;
function onYouTubeIframeAPIReady() {
  player = new YT.Player('player', {
    videoId: 'fgxk6hdHqxE',
    events: {
      'onReady': onPlayerReady,
      'onStateChange': onPlayerStateChange
    }
  });
}
function onPlayerReady(event) {
  event.target.playVideo();
}
function onPlayerStateChange(event) {
  player.setPlaybackRate(1.5);
}