我正在开发一个21点游戏。到目前为止，除了这个小细节之外，一切都正常。基本上，开始游戏按钮只应在游戏之前和游戏之后可见。我没有问题，可以将其设置为隐藏，但是当我完成一局游戏时，它不起作用。

function startGame() {
    startGameButton.style.visibility = "hidden";
    if (!player.playerName) {
        player.playerName = prompt("你叫什么名字？")
        player.chips = 100

        playerEl.textContent = "玩家：" + player.playerName;
    }

    if (cards.length < 2) {
        let bet = prompt('你想下注多少（筹码：' + player.chips + '）')
        player.chips = player.chips - bet;
        chipsEl.textContent = "筹码：" + player.chips;
    }

    let firstCard = randomCard();
    let secondCard = randomCard();
    cards = [firstCard, secondCard];
    let tableFirstCard = randomCard();
    let tableSecondCard = randomCard();
    tableCards = [tableFirstCard, tableSecondCard];
    let message = "";
    let hasBlackJack = false;
    let isAlive = true;

    sum = firstCard + secondCard;
    newCardButton.style.visibility = "visible";
    startGameButton.textContent = "新游戏";

    if (sum < 21) {
        message = "你想要抽一张新牌吗？";
    } else if (sum === 21) {
        message = "你得到了21点！";
        newCardButton.style.visibility = "hidden";
        startGameButton.style.visibility = "visible";
        player.chips = player.chips + bet * 2
        hasBlackJack = true;
    } else {
        startGameButton.style.visibility = "visible";
        isAlive = false;
        message = "运气不好！你已经离开游戏了！";
    }

    messageEl.textContent = message;
    cardsEl.textContent = "牌：" + firstCard + " " + secondCard;
    tableCardsEl.textContent = "桌面牌：" + tableSecondCard + " " + tableSecondCard;
    sumEl.textContent = "总和：" + sum;
    console.log("21点：" + hasBlackJack);
    console.log("存活：" + isAlive);
}

我甚至尝试交换顺序，看看是否有任何区别，但是发生的一切都是：

if (sum < 21) {
        message = "你想要抽一张新牌吗？";
    } else if (sum === 21) {
        message = "你得到了21点！";
        newCardButton.style.visibility = "hidden";
        startGameButton.style.visibility = "visible";
        player.chips = player.chips + bet * 2
        hasBlackJack = true;
    } else {
        startGameButton.style.visibility = "visible";
        isAlive = false;
        message = "运气不好！你已经离开游戏了！";
    }

if语句中的所有内容都在发生，除了可见性部分。

如果需要更多上下文，请参考代码链接：https://github.com/pedrosilva410/blackjack-game