#youtube-movie {
  margin: 0 auto;
  width: 100%;
  max-width: 1280px; /* 最大の横幅 */
}
 
#youtube-movie-content {
  padding-top: 56.25%;
  position: relative;
  width: 100%;
}
 
#youtube-movie-content iframe {
  height: 100% !important;
  left: 0;
  position: absolute;
  top: 0;
  width: 100% !important;
}