/* ── 背景音乐开关按钮 ── */
.bgm-toggle {
  position: fixed;
  bottom: 24px;
  right: 16px;
  z-index: 9999;
  width: 36px;
  height: 36px;
  border-radius: 50%;
  border: 1.5px solid rgba(200, 160, 106, 0.4);
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: blur(8px);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 0.3s ease;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.08);
}
.bgm-toggle:hover {
  background: rgba(255, 255, 255, 0.95);
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.12);
  transform: scale(1.08);
}

.bgm-icon {
  font-size: 16px;
  color: #999;
  transition: color 0.3s ease;
  line-height: 1;
}

/* 播放中：图标旋转 + 金色 */
.bgm-toggle.playing .bgm-icon {
  color: #C8A06A;
  animation: bgmSpin 2.5s linear infinite;
}

/* 暂停时：灰色 + 删除线效果 */
.bgm-toggle:not(.playing) {
  opacity: 0.7;
}

@keyframes bgmSpin {
  from { transform: rotate(0deg); }
  to   { transform: rotate(360deg); }
}

/* 手机端稍微小一点 */
@media (max-width: 480px) {
  .bgm-toggle {
    width: 32px;
    height: 32px;
    bottom: 20px;
    right: 12px;
  }
  .bgm-icon { font-size: 14px; }
}