void PinsHaveSettled()  //球擊中瓶子之後瓶子存留數固定不再變動之後
    {
        int pinFall = bowlStartPinCount - lastStandingCount;

        bowlStartPinCount = lastStandingCount;
        gameManager.Bowl(pinFall);
        Debug.Log("Knocked down " + pinFall + " pin(s).");

        lastStandingCount = -1;
        ballLeftBox       = false;
        pinAmount.color   = Color.green;
    }