.game-container {
  max-width: 400px;
  margin: 0 auto;
  text-align: center;
}

#game-board {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 10px;
  background: #bbada0;
  padding: 10px;
  border-radius: 10px;
  touch-action: none;
}

.tile {
  width: 80px;
  height: 80px;
  line-height: 80px;
  font-size: 24px;
  font-weight: bold;
  background: #ccc0b3;
  color: #776e65;
  border-radius: 6px;
  transition: all 0.2s ease-in-out;
}

.top-bar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 10px;
}

.score-board {
  background: #eee;
  padding: 0.5em 1em;
  border-radius: 5px;
  font-weight: bold;
}

.tips {
  margin-top: 10px;
  color: #999;
  font-size: 0.9em;
}

@media (max-width: 500px) {
  .tile {
    width: 60px;
    height: 60px;
    line-height: 60px;
    font-size: 18px;
  }

  #game-board {
    gap: 8px;
  }
}
.tile {
  transition: transform 0.2s ease, background 0.2s ease;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 24px;
  font-weight: bold;
  border-radius: 6px;
  color: #776e65;
}

.tile.spawn {
  animation: pop 0.25s ease-out;
}

@keyframes pop {
  0% { transform: scale(0.5); opacity: 0.5; }
  100% { transform: scale(1); opacity: 1; }
}

.restart-btn {
  padding: 0.5em 1em;
  background: #e67e22;
  color: white;
  border: none;
  border-radius: 5px;
  font-size: 0.9em;
  cursor: pointer;
  margin-left: 10px;
}

.restart-btn:hover {
  background: #cf711f;
}