Javascript倒计时应用程序不工作

function startCountdown(endTime) {
    const interval = setInterval(() => {
        const now = new Date().getTime();
        const distance = endTime - now;

        if (distance < 0) {
            clearInterval(interval);
            document.getElementById('countdown').innerHTML = 'EXPIRED';
            return;
        }

        const days = Math.floor(distance / (1000 * 60 * 60 * 24));
        const hours = Math.floor((distance % (1000 * 60 * 60 * 24)) / (1000 * 60 * 60));
        const minutes = Math.floor((distance % (1000 * 60 * 60)) / (1000 * 60));
        const seconds = Math.floor((distance % (1000 * 60)) / 1000);

        document.getElementById('countdown').innerHTML = `${days}d ${hours}h ${minutes}m ${seconds}s`;
    }, 1000);
}

const endTime = new Date("Sep 30, 2023 23:59:59").getTime();
startCountdown(endTime);

function startCountdown(endTime) {
    function updateCountdown() {
        const now = new Date().getTime();
        const distance = endTime - now;

        if (distance < 0) {
            document.getElementById('countdown').innerHTML = 'EXPIRED';
            return;
        }

        const days = Math.floor(distance / (1000 * 60 * 60 * 24));
        const hours = Math.floor((distance % (1000 * 60 * 60 * 24)) / (1000 * 60 * 60));
        const minutes = Math.floor((distance % (1000 * 60 * 60)) / (1000 * 60));
        const seconds = Math.floor((distance % (1000 * 60)) / 1000);

        document.getElementById('countdown').innerHTML = `${days}d ${hours}h ${minutes}m ${seconds}s`;

        requestAnimationFrame(updateCountdown);
    }

    requestAnimationFrame(updateCountdown);
}

const endTime = new Date("Sep 30, 2023 23:59:59").getTime();
startCountdown(endTime);