document.addEventListener("DOMContentLoaded", () => {

  // ── Register button
  const regBtn = document.getElementById("reg-btn");
  if (regBtn) {
    regBtn.addEventListener("click", () => {
      alert("Frontend skeleton only. Backend will be connected later.");
    });
  }

  // ── Smooth scroll for all anchor links
  document.querySelectorAll('a[href^="#"]').forEach(link => {
    link.addEventListener("click", e => {
      const id = link.getAttribute("href").slice(1);
      const target = document.getElementById(id);
      if (!target) return;
      e.preventDefault();
      const headerH = document.querySelector(".header").offsetHeight;
      const top = target.getBoundingClientRect().top + window.scrollY - headerH - 16;
      window.scrollTo({ top, behavior: "smooth" });
    });
  });

  // ── Scroll reveal
  const reveals = document.querySelectorAll(".reveal");
  const io = new IntersectionObserver((entries) => {
    entries.forEach(entry => {
      if (entry.isIntersecting) {
        entry.target.classList.add("visible");
        io.unobserve(entry.target);
      }
    });
  }, { threshold: 0.12 });

  reveals.forEach(el => io.observe(el));
});