.black-screen
{
  background-color: #000;
  height: 100vh;
  margin: 0;
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 900000;
  display: none;
}

.black-screen .unlock-zone
{
    position: absolute;
    top: 0;
    right: 0;
    width: 33vw;
    height: 33vw;
    margin: 0;
    background-color: #000;
    z-index: 900001;
}