htbl,body{
  overflow:hidden;
}

h1{
  font-size:32px;
  position:absolute;
  left:0;
  bottom:0;
  font-weight:bold;
}

#demo{
  position:relative;
  top:0;
  left:0;
}
#demo ul{
  position:relative;
  left:0;
  top:10vmin;
  width:90%;
  margin:0 auto;
  user-select:none;
}
#demo ul li{
  position:absolute;
  cursor:pointer;
  top:0;
  text-align:center;
}

#demo ul li img{
  position:absolute;
}
.cup{
  z-index:3;
  width:100%;
  top: 0;
  right: 0;
  bottom: 0;
  left: 0;
  margin: auto;
  cursor:pointer;
}
.cup:hover{
  transform: translateY(4px);
}

.ball{
  z-index:1;
  width:20%;
  right: 0;
  bottom: 0;
  left: 0;
  margin: auto;
}
.layer{
  position:absolute;
  top: 0;
  right: 0;
  z-index:99;
  width:100%;
  height:100%;
  background-color:rgba(0,0,0,0.1);
  cursor:pointer;
}