// ... existing code ...

// === AMBIENT SOUND TOGGLE ===
let ambientSound = document.getElementById('ambient-sound');
let audioToggle = document.getElementById('audio-toggle');

// Load user's audio preference
const storedMute = localStorage.getItem('nexus-ambient-muted') === 'true';
if (storedMute) {
  ambientSound.muted = true;
  audioToggle.classList.add('muted');
} else {
  ambientSound.muted = false;
  audioToggle.classList.remove('muted');
}

audioToggle.addEventListener('click', () => {
  ambientSound.muted = !ambientSound.muted;
  if (ambientSound.muted) {
    audioToggle.classList.add('muted');
  } else {
    audioToggle.classList.remove('muted');
  }
  localStorage.setItem('nexus-ambient-muted', ambientSound.muted);
});

// ... existing code ...