/* Voice Ripple Piano - 補充樣式 */

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  background-color: #1a1d2e;
}

/* Canvas 定位 */
canvas {
  display: block;
  position: fixed;
  top: 0;
  left: 0;
}

/* 開始畫面過渡動畫 */
#start-screen {
  transition: opacity 0.3s ease-out;
}

/* 開始按鈕 glow 效果 */
.start-button {
  box-shadow: 0 4px 25px rgba(255, 255, 255, 0.15);
  animation: pulse 2s ease-in-out infinite;
}

.start-button:hover {
  box-shadow: 0 6px 35px rgba(255, 255, 255, 0.25);
}

@keyframes pulse {
  0%, 100% {
    transform: scale(1);
    box-shadow: 0 4px 25px rgba(255, 255, 255, 0.15);
  }
  50% {
    transform: scale(1.02);
    box-shadow: 0 6px 30px rgba(255, 255, 255, 0.2);
  }
}