body{
  overflow:hidden;
  background-color:#ddd;
}
#demo{
  position:relative;
  top:0;
  left:0;
}
input{
  width:99%;
  padding:8px 0;
  font-size:24px;
}
#stage{
  text-align:center;
  font-size:64px;
  font-weight:bold;
}
#panels{
  display:flex;
}

#panels canvas{
  width:50%;
  cursor:pointer;
}
#panels canvas:hover{
  opacity:0.8;
}
canvas:hover{
  background-color:#aaa;
}
canvas.selected{
  background-color:#fff;
}

#answer.answered{
  position:fixed;
  top:0;
  left:0;
  width:100%;
  height:100%;
  font-size:20vw;
  line-height:240px;
  text-align:center;
  background-color:rgba(0,0,0,0.1);
  cursor:pointer;
}