/* Only images you mark as yt-thumb */
.yt-thumb .vc_single_image-wrapper {
  position: relative;
  display: inline-block;
}

.yt-thumb .vc_single_image-wrapper::after {
  content: "";
  position: absolute;
  top: 50%;
  left: 50%;
  width: 64px;
  height: 64px;
  transform: translate(-50%, -50%);
  background: url("https://Ywww.trike-bike.com.au/wp-content/uploads/youtube-overlay.png") no-repeat center;
  background-size: contain;
  pointer-events: none;
  z-index: 5;
}