script.js

// Mobile Navigation Toggle
const hamburger = document.querySelector('.hamburger');
const navMenu = document.querySelector('.nav-menu');

if (hamburger && navMenu) {
    hamburger.addEventListener('click', () => {
        navMenu.classList.toggle('active');
        hamburger.classList.toggle('active');
    });

    document.querySelectorAll('.nav-link').forEach(link => {
        link.addEventListener('click', () => {
            navMenu.classList.remove('active');
            hamburger.classList.remove('active');
        });
    });
}

// Mark active nav link based on current page
(function markActiveNav() {
    const page = location.pathname.split('/').pop() || 'index.html';
    document.querySelectorAll('.nav-link').forEach(link => {
        const href = link.getAttribute('href') || '';
        const hrefPage = href.split('/').pop().split('#')[0];
        if (hrefPage && hrefPage === page) {
            link.classList.add('active');
        } else if (page === '' && hrefPage === 'index.html') {
            link.classList.add('active');
        }
    });
})();

// Update last updated date
const lastUpdatedEl = document.getElementById('last-updated');
if (lastUpdatedEl) {
    lastUpdatedEl.textContent = new Date().toLocaleDateString('en-US', {
        year: 'numeric', month: 'long', day: 'numeric'
    });
}

// Smooth scroll for anchor links on the same page
document.querySelectorAll('a[href^="#"]').forEach(anchor => {
    anchor.addEventListener('click', function (e) {
        const target = document.querySelector(this.getAttribute('href'));
        if (target) {
            e.preventDefault();
            window.scrollTo({ top: target.offsetTop - 75, behavior: 'smooth' });
        }
    });
});

// Navbar shadow on scroll
window.addEventListener('scroll', () => {
    const navbar = document.querySelector('.navbar');
    if (!navbar) return;
    navbar.style.backgroundColor = window.scrollY > 50
        ? 'rgba(255,255,255,0.98)'
        : 'rgba(255,255,255,0.95)';
});

// Fade-in animation
const fadeEls = document.querySelectorAll('.section, .section-alt');
if ('IntersectionObserver' in window && fadeEls.length) {
    const obs = new IntersectionObserver(entries => {
        entries.forEach(e => {
            if (e.isIntersecting) {
                e.target.style.opacity = '1';
                e.target.style.transform = 'translateY(0)';
            }
        });
    }, { threshold: 0, rootMargin: '0px 0px -40px 0px' });

    fadeEls.forEach(el => {
        el.style.opacity = '0';
        el.style.transform = 'translateY(18px)';
        el.style.transition = 'opacity 0.55s ease, transform 0.55s ease';
        obs.observe(el);
    });
} else {
    fadeEls.forEach(el => { el.style.opacity = '1'; el.style.transform = 'none'; });
}

// Generic filter buttons (projects / news pages)
document.querySelectorAll('.filter-btn').forEach(btn => {
    btn.addEventListener('click', () => {
        const group = btn.closest('.project-filter, .news-filter');
        if (group) group.querySelectorAll('.filter-btn').forEach(b => b.classList.remove('active'));
        btn.classList.add('active');

        const target = btn.dataset.filter;
        const cards = document.querySelectorAll('[data-category]');
        cards.forEach(card => {
            card.style.display = (target === 'all' || card.dataset.category === target) ? '' : 'none';
        });
    });
});