body {
  margin: 0;
  padding: 0;
  background-color: #202020;
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100vh;
  overflow: hidden;
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

#game-container {
  position: relative;
  box-shadow: 0 0 20px rgba(0,0,0,0.5);
}

canvas {
  display: block;
  background-color: #5c94fc; /* 天空蓝 */
  image-rendering: pixelated; /* 保持像素风格清晰 */
}

#ui-layer {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
}

#score {
  position: absolute;
  top: 20px;
  left: 20px;
  color: white;
  font-size: 24px;
  font-weight: bold;
  text-shadow: 2px 2px 0 #000;
}

#controls-hint {
  position: absolute;
  bottom: 10px;
  left: 0;
  width: 100%;
  text-align: center;
  color: rgba(255, 255, 255, 0.8);
  font-size: 14px;
  text-shadow: 1px 1px 0 #000;
}

#game-over, #game-win {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  text-align: center;
  color: white;
  text-shadow: 4px 4px 0 #000;
}

#game-over h1, #game-win h1 {
  font-size: 64px;
  margin: 0 0 20px 0;
  color: #ff4444;
}

#game-win h1 {
  color: #44ff44;
}

.hidden {
  display: none;
}