document.addEventListener('DOMContentLoaded', function(){
// 1) Mobile menu toggle
var btn = document.querySelector('.mobile-menu-toggle');
var menu = document.querySelector('.nav-menu ul');
btn && btn.addEventListener('click', function(){
menu.classList.toggle('open');
});
// 2) Sticky header on scroll
window.addEventListener('scroll', function(){
document.querySelector('.site-header')
.classList.toggle('sticky', window.scrollY > 50);
});
});
