script.js

const countdownDate = new Date('2050-05-20T12:00:00+07:00').getTime();
const daysEl = document.getElementById('days');
const hoursEl = document.getElementById('hours');
const minutesEl = document.getElementById('minutes');
const secondsEl = document.getElementById('seconds');

function updateCountdown() {
  if (!daysEl || !hoursEl || !minutesEl || !secondsEl) return;
  const now = Date.now();
  const distance = countdownDate - now;

  if (distance <= 0) {
    daysEl.textContent = hoursEl.textContent = minutesEl.textContent = secondsEl.textContent = '0';
    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);

  daysEl.textContent = days;
  hoursEl.textContent = hours;
  minutesEl.textContent = minutes;
  secondsEl.textContent = seconds;
}

setInterval(updateCountdown, 1000);
updateCountdown();

const audioBtn = document.querySelector('[data-audio-btn]');
const audio = document.getElementById('bg-audio');

audioBtn?.addEventListener('click', async () => {
  if (!audio) return;

  try {
    if (audio.paused) {
      await audio.play();
      audioBtn.classList.add('is-playing');
    } else {
      audio.pause();
      audioBtn.classList.remove('is-playing');
    }
  } catch (error) {
    console.warn('Không thể phát nhạc:', error);
  }
});