/// <summary>
 /// 停止播放背景音乐
 /// </summary>
 public void StopBackgroundMusic()
 {
     if (BackgroundAudio.isPlaying)
     {
         BackgroundAudio.Stop();
     }
 }
        /// <summary>
        /// 播放背景音乐
        /// </summary>
        /// <param name="clip">音乐剪辑</param>
        /// <param name="isLoop">是否循环</param>
        /// <param name="speed">播放速度</param>
        public void PlayBackgroundMusic(AudioClip clip, bool isLoop = true, float speed = 1)
        {
            if (BackgroundAudio.isPlaying)
            {
                BackgroundAudio.Stop();
            }

            BackgroundAudio.clip  = clip;
            BackgroundAudio.loop  = isLoop;
            BackgroundAudio.pitch = speed;
            BackgroundAudio.Play();
        }