.zz-box .vi {
  position: absolute;
 
  left: 0%;
  top: 0%;
  width: 100%;
  height: 100%;
  opacity: 0;
  z-index: -1;
}
.zz-box .vi.show {
  opacity: 1;
}
.zz-box .vi video {
  width: 100%;
  height: 100%;
  -o-object-fit: cover;
     object-fit: cover;
}
.zz-box{
    position: relative;
}