Responsive Vimeo container (e.g. iframe for Vimeo ) by scss

index.html

<div class="video-container">
  <iframe src="http://player.vimeo.com/video/78074896" width="500" height="281" frameborder="0"></iframe>
</div>

video_container.scss

.video-container{
  position: relative;
  padding-bottom: 56.25%;     
  margin: 0 auto; // if make it center
  iframe, object, embed{
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
  }
}