document.addEventListener('DOMContentLoaded', function () {
    // Mobile menu toggle
    const hamburger = document.querySelector('.nav__hamburger');
    const navLinks = document.querySelector('.nav__links');

    hamburger.addEventListener('click', function () {
        navLinks.classList.toggle('active');
        hamburger.classList.toggle('open');
    });

    // Close mobile menu on link click
    navLinks.querySelectorAll('a').forEach(function (link) {
        link.addEventListener('click', function () {
            navLinks.classList.remove('active');
            hamburger.classList.remove('open');
        });
    });

    // Scroll animations
    const faders = document.querySelectorAll('.fade-in');
    const observer = new IntersectionObserver(function (entries) {
        entries.forEach(function (entry) {
            if (entry.isIntersecting) {
                entry.target.classList.add('visible');
                observer.unobserve(entry.target);
            }
        });
    }, { threshold: 0.15 });

    faders.forEach(function (el) {
        observer.observe(el);
    });

    // Budget calculator
    var slider = document.getElementById('budgetSlider');
    if (slider) {
        var MIN_FEE = 800;

        function formatPLN(val) {
            return val.toLocaleString('pl-PL') + ' zł';
        }

        function updateCalc() {
            var budget = parseInt(slider.value);
            var fee = Math.max(budget * 0.1, MIN_FEE);
            var total = budget + fee;

            document.getElementById('budgetValue').textContent = formatPLN(budget);
            document.getElementById('calcBudget').textContent = formatPLN(budget);
            document.getElementById('calcFee').textContent = formatPLN(fee);
            document.getElementById('calcTotal').textContent = formatPLN(total);
        }

        slider.addEventListener('input', updateCalc);
        updateCalc();
    }

    // Smooth scroll for anchor links
    document.querySelectorAll('a[href^="#"]').forEach(function (anchor) {
        anchor.addEventListener('click', function (e) {
            var target = document.querySelector(this.getAttribute('href'));
            if (target) {
                e.preventDefault();
                target.scrollIntoView({ behavior: 'smooth', block: 'start' });
            }
        });
    });
});