body { margin:0; overflow:hidden; }
canvas { display:block; }

#info {
  position:absolute;
  top:10px;
  left:10px;
  color:white;
  font-family:sans-serif;
  z-index:1;
  background:rgba(0,0,0,0.3);
  padding:5px;
  border-radius:5px;
}

#inventory {
  position:absolute;
  bottom:10px;
  left:50%;
  transform:translateX(-50%);
  display:flex;
  gap:5px;
  z-index:1;
}

.block-btn {
  width:40px;
  height:40px;
  border:2px solid white;
  cursor:pointer;
}

.selected { border-color:yellow; }