#tool-area {
  padding: 24px 0;
}
img {
  background-color: black;
}
#gu {
  display: none;
  width: 100%;
}
#choki {
  display: none;
  width: 100%;
}
#pa {
  display: none;
  width: 100%;
}
#message {
  width: 100%;
  height: 560px;
  text-align: center;
  font-size: 10rem;
  line-height: 560px;
  background-color: black;
  color: yellow;
  font-weight: bold;
}
#startBtn {
  display: block;
  margin: 24px auto;
  font-size: 1.8rem;
  padding: 0 24px;
  line-height: 3rem;
  height: 3rem;
}