.youtube_wrapper { width: 90%; max-width:820px; margin: 0 auto; }
.youtube_wrapper .aspect { width: 100%; height: auto; position: relative; overflow: hidden; }
.youtube_wrapper .aspect.aspect56 { padding-top: 56.25%; }
.youtube_wrapper .aspect .aspectBlock { position: absolute; top: 0; width: 100%; height: 100%; }
.youtube_wrapper iframe{ width:100%; height: 100%;}