.image-wrap {
  position: relative;
  display: inline-block;
}

.play-button {
  position: absolute;
  width: 60px;
  height: 60px;
  background-color: rgba(0,0,0,0.25);
  border-radius: 100%;
  top: 50%;
  left: 50%;
  margin: -30px 0 0 -30px;
  cursor: pointer;
}

.play-button:after {
  content: '';
  display: block;
  position: absolute;
  left: 22px;
  top: 10px;
  border-width: 20px;
  border-style: solid;
  border-color: transparent transparent transparent white;
}

.play-button:hover {
  background-color: black;
}