document.addEventListener('DOMContentLoaded', function() {
    
    const navLinks = document.querySelectorAll('nav a');
    navLinks.forEach(link => {
        link.addEventListener('click', function(e) {
            e.preventDefault();
            const targetId = this.getAttribute('href');
            const targetSection = document.querySelector(targetId);
            
            if (targetSection) {
                targetSection.scrollIntoView({
                    behavior: 'smooth',
                    block: 'start'
                });
            }
        });
    });

    //Dark MOde
    const darkModeBtn = document.getElementById('darkModeBtn');
    
    if (darkModeBtn) {
        if (localStorage.getItem('darkMode') === 'enabled') {
            document.body.classList.add('dark-mode');
            darkModeBtn.textContent = ' Light Mode';
        }

        darkModeBtn.addEventListener('click', function() {
            document.body.classList.toggle('dark-mode');
            
            if (document.body.classList.contains('dark-mode')) {
                localStorage.setItem('darkMode', 'enabled');
                darkModeBtn.textContent = ' Light Mode';
            } else {
                localStorage.setItem('darkMode', 'disabled');
                darkModeBtn.textContent = ' Dark Mode';
            }
        });
    }

    //Them changer
    const colorButtons = document.querySelectorAll('.color-btn');
    
    colorButtons.forEach(button => {
        button.addEventListener('click', function() {
            const color = this.getAttribute('data-color');
            const darkColor = this.getAttribute('data-color-dark');
            
            document.documentElement.style.setProperty('--main-color', color);
            document.documentElement.style.setProperty('--main-color-dark', darkColor);
            
            localStorage.setItem('themeColor', color);
            localStorage.setItem('themeColorDark', darkColor);
            
            colorButtons.forEach(btn => btn.classList.remove('active'));
            this.classList.add('active');
        });
    });

    const savedColor = localStorage.getItem('themeColor');
    const savedColorDark = localStorage.getItem('themeColorDark');
    
    if (savedColor && savedColorDark) {
        document.documentElement.style.setProperty('--main-color', savedColor);
        document.documentElement.style.setProperty('--main-color-dark', savedColorDark);
        
        colorButtons.forEach(btn => {
            if (btn.getAttribute('data-color') === savedColor) {
                btn.classList.add('active');
            }
        });
    }

    // Validation of FORM 
    const form = document.querySelector('#contact form');
    
    if (form) {
        const nameInput = form.querySelector('input[name="name"]');
        const emailInput = form.querySelector('input[name="email"]');
        const messageInput = form.querySelector('textarea[name="message"]');

        nameInput.addEventListener('input', function() {
            if (this.value.trim().length > 2) {
                this.style.borderColor = '#4caf50';
            } else {
                this.style.borderColor = '#e0e0e0';
            }
        });

        emailInput.addEventListener('input', function() {
            const emailPattern = /^[^\s@]+@[^\s@]+\.[^\s@]+$/;
            if (emailPattern.test(this.value)) {
                this.style.borderColor = '#4caf50';
            } else {
                this.style.borderColor = '#f44336';
            }
        });

        messageInput.addEventListener('input', function() {
            if (this.value.trim().length >= 10) {
                this.style.borderColor = '#4caf50';
            } else {
                this.style.borderColor = '#e0e0e0';
            }
        });

        form.addEventListener('submit', function(e) {
            e.preventDefault();
            
            const name = nameInput.value.trim();
            const email = emailInput.value.trim();
            const message = messageInput.value.trim();
            
            if (name.length < 3) {
                alert('Bitte geben Sie eine gültige E-Mail-Adresse ein!');
                nameInput.focus();
                return;
            }
            
            const emailPattern = /^[^\s@]+@[^\s@]+\.[^\s@]+$/;
            if (!emailPattern.test(email)) {
                alert('Der Name muss mindestens 3 Zeichen lang sein!');
                emailInput.focus();
                return;
            }
            
            if (message.length < 10) {
                alert('Die Nachricht muss mindestens 10 Zeichen lang sein!');
                messageInput.focus();
                return;
            }
            
            alert('Vielen Dank, ' + name + '! Ihre Nachricht wurde gesendet.');
            form.reset();
            
            nameInput.style.borderColor = '#e0e0e0';
            emailInput.style.borderColor = '#e0e0e0';
            messageInput.style.borderColor = '#e0e0e0';
        });
    }
});