document.addEventListener('DOMContentLoaded', () => {
  const observer = new IntersectionObserver(
    (entries) => {
      entries.forEach((entry) => {
        if (entry.isIntersecting) {
          entry.target.classList.add('is-visible');
          observer.unobserve(entry.target);
        }
      });
    },
    { threshold: 0.14, rootMargin: '0px 0px -30px 0px' }
  );

  document.querySelectorAll('.reveal').forEach((node) => observer.observe(node));
});