.video-item:after{
  position: absolute;
  content: "";
  left: 0;
  top: 0; 
  width: 100%;
  height: 100%;
  background-color: rgba(0, 0, 0, 0.6);
  opacity: 0;
  border-radius: 12px;
  transition: all 0.5s ease-in-out;
}
.video-item:hover:after{
  opacity: 1;
}
.play-btn{
  opacity: 0;
  transition: all 0.5s ease-in-out;
}
.video-item:hover .play-btn{
  opacity: 1;
}