export function bindScrollToTop(button) {
  if (!button) return;

  function updateVisibility() {
    button.hidden = window.scrollY <= 480;
  }

  window.addEventListener('scroll', updateVisibility, { passive: true });
  button.addEventListener('click', () => {
    const reduceMotion = window.matchMedia('(prefers-reduced-motion: reduce)').matches;
    window.scrollTo({ top: 0, behavior: reduceMotion ? 'auto' : 'smooth' });
  });
  updateVisibility();
}