SCSS for the Sencha Youtube component (https://gist.github.com/alexkravets/5416594) to support play overlay and some styling.

x-youtube.scss

.x-youtube                            {
  &:after                             { content: '';
                                        display: block;
                                        position: absolute;
                                        width:100%;
                                        height:100%;
                                        background: url('../images/youtube-play@2x.png') no-repeat center;
                                        background-size: 58px 58px;
  }

  &.x-youtube-overlay                 {
    &:after                           { background-color: rgba(0,0,0,0.5);
    }
  }

  &.x-youtube-loading                 {
    &:after                           { background-image: none;
    }
  }

  iframe                              { border: 0;
  }
}