body {
  background-color: #222;
  color: white;
  font-family: Arial, sans-serif;
  text-align: center;
  margin: 0;
  padding: 20px;
}

h1 {
  margin-bottom: 20px;
}

#board {
  display: grid;
  grid-template-columns: repeat(2, 150px);
  gap: 15px;
  justify-content: center;
  margin-bottom: 20px;
}

.color-btn {
  width: 150px;
  height: 150px;
  border-radius: 15px;
  opacity: 0.8;
  transition: opacity 0.2s, transform 0.2s;
  cursor: pointer;
}

.color-btn.active {
  opacity: 1;
  transform: scale(1.05);
}

.red { background: red; }
.green { background: green; }
.blue { background: blue; }
.yellow { background: yellow; }

#start {
  padding: 10px 20px;
  font-size: 18px;
  background: #555;
  color: white;
  border: none;
  border-radius: 5px;
  cursor: pointer;
}

#start:hover {
  background: #777;
}

#info {
  margin-top: 15px;
  font-size: 18px;
}