mixins-collection.sass

// Best added in :before or :after
@mixin img_overlay($width, $height, $url : '../img/video-player.png' ) {
  background-image: url($url);
  max-width: #{$width}px;
  max-height: #{$height}px;
  content: ' ';
  display: block;
  width: 100%;
  position: absolute;
  height: 100%;
  top: calc(50% - #{$height}px + (#{$height}px / 2) );
  background-repeat: no-repeat;
  left: calc(50% - #{$width}px + (#{$width}px / 2) );
}