.controls {
  flex-direction: column;
  align-items: center;
}

body {
  margin: 0;
  overflow: hidden;
  background: linear-gradient(135deg, #e0f7fa, #b2ebf2, #80deea, #4dd0e1, #26c6da);
  font-family: 'Arial', sans-serif;
}

canvas {
  display: block;
}

.controls {
  position: fixed;
  bottom: 20px;
  left: 50%;
  transform: translateX(-50%);
  z-index: 100;
  padding: 10px;
  display: flex;
  flex-direction: row;
  flex-wrap: wrap;
  justify-content: center;
  gap: 10px;
  width: auto;
  max-width: 90%;
  background-color: rgba(255, 255, 255, 0.1);
  backdrop-filter: blur(5px);
  border-radius: 12px;
}

button {
  padding: 12px 24px;
  font-size: 16px;
  cursor: pointer;
  border-radius: 8px;
  border: none;
  background-color: rgba(255, 255, 255, 0.2);
  color: white;
  backdrop-filter: blur(5px);
  transition: all 0.3s ease;
  min-width: 150px;
  text-align: center;
}

button:hover {
  background-color: rgba(153, 229, 255, 0.7);
  transform: translateY(-2px);
}

button:active {
  transform: translateY(0);
}

.play-btn {
  background-color: #99c2ff;  
}

.confetti-btn {
  background-color: #68a4fd; 
}

.change-music-btn {
  background-color: #99c2ff; /* 浅蓝色 */
}

.change-music-btn:hover {
  background-color: rgba(153, 229, 255, 0.7); /* 浅蓝色悬停效果 */
}

.immerse-btn {
  background-color: #68a4fd; /* 深蓝色 */
}



.immerse-btn:active {
  transform: translateY(0);
}

/* Loading indicator */
.loading {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.8);
  display: flex;
  justify-content: center;
  align-items: center;
  color: white;
  font-size: 24px;
  z-index: 1000;
}

@media (max-width: 768px) {
  button {
    padding: 8px 16px;
    font-size: 14px;
    min-width: 120px;
  }
  
  .controls {
    flex-direction: column;
    align-items: center;
  }
}