/* Keep decorative equipment traffic paused when off screen or reduced motion is requested. */
(() => {
  const scenes = [...document.querySelectorAll('.motion-overlay')];
  if (!scenes.length) return;
  const reduced = window.matchMedia('(prefers-reduced-motion: reduce)');
  const update = (svg, visible) => {
    svg.dataset.visible = visible ? '1' : '0';
    const active = visible && !reduced.matches;
    svg.parentElement.classList.toggle('is-active', active);
    if (active) svg.unpauseAnimations();
    else svg.pauseAnimations();
  };
  scenes.forEach(svg => update(svg, false));
  if ('IntersectionObserver' in window) {
    const observer = new IntersectionObserver(entries => {
      entries.forEach(entry => update(entry.target, entry.isIntersecting));
    }, {rootMargin: '80px 0px', threshold: 0.01});
    scenes.forEach(svg => observer.observe(svg));
  } else {
    scenes.forEach(svg => update(svg, true));
  }
  const refresh = () => scenes.forEach(svg => update(svg, svg.dataset.visible === '1'));
  if (reduced.addEventListener) reduced.addEventListener('change', refresh);
  else reduced.addListener(refresh);
})();