(function() {
  'use strict';
  
  const frames = [
    "https://cdn.prod.website-files.com/692487b717cd11b0ad36e79a/6931ae113d658a370461cab6_256-black.png",
    "https://cdn.prod.website-files.com/692487b717cd11b0ad36e79a/6931ae88664c688760d6320d_256-white.png",
  ];
  const speed = 2000;

  let link = null;
  let intervalId = null;
  let frameIndex = 0;
  let lastUpdate = 0;

  function getOrCreateFavicon() {
    if (!link || !document.head.contains(link)) {
      document.querySelectorAll('link[rel*="icon"]').forEach(el => el.remove());
      link = document.createElement('link');
      link.id = 'favicon';
      link.rel = 'icon';
      link.type = 'image/png';
      link.href = frames[0];
      document.head.appendChild(link);
      frameIndex = 0;
    }
    return link;
  }

  function updateFavicon() {
    if (!link) return;
    frameIndex = (frameIndex + 1) % frames.length;
    link.href = frames[frameIndex];
  }

  function animate(now) {
    if (now - lastUpdate >= speed) {
      lastUpdate = now;
      updateFavicon();
    }
    
    if (document.hidden) {
      return;
    }
    
    intervalId = requestAnimationFrame(animate);
  }

  function startAnimation() {
    if (intervalId) return;
    
    getOrCreateFavicon();
    lastUpdate = performance.now();
    
    if (document.hidden) {
      const handleVisibilityChange = () => {
        if (!document.hidden && !intervalId) {
          startAnimation();
        }
      };
      document.addEventListener('visibilitychange', handleVisibilityChange, { once: true });
      return;
    }
    
    intervalId = requestAnimationFrame(animate);
  }

  function stopAnimation() {
    if (intervalId) {
      cancelAnimationFrame(intervalId);
      intervalId = null;
    }
  }

  function init() {
    startAnimation();
    
    document.addEventListener('visibilitychange', () => {
      if (document.hidden) {
        stopAnimation();
      } else {
        startAnimation();
      }
    });

    const mo = new MutationObserver((mutations) => {
      const faviconRemoved = mutations.some(mutation => 
        Array.from(mutation.removedNodes).some(node => 
          node === link || (node.nodeName === 'LINK' && node.id === 'favicon')
        )
      );
      
      if (faviconRemoved || !document.getElementById('favicon')) {
        stopAnimation();
        startAnimation();
      }
    });
    
    mo.observe(document.head, { childList: true, subtree: true });
  }

  if (document.readyState === 'loading') {
    document.addEventListener('DOMContentLoaded', init);
  } else {
    init();
  }
})();