script.js

// Gerenciador de Abas
function openTab(tabName) {
    // Esconder todas as seções
    const contents = document.querySelectorAll('.tab-content');
    contents.forEach(content => content.classList.remove('active'));

    // Remover estado ativo dos links
    const links = document.querySelectorAll('.tab-link');
    links.forEach(link => link.classList.remove('active'));

    // Ativar a seção e o link clicado
    document.getElementById(tabName).classList.add('active');
    document.getElementById('link-' + tabName).classList.add('active');

    window.scrollTo({ top: 0, behavior: 'smooth' });
}

// Lógica da Calculadora de Juros Compostos
function calculateInterest() {
    const initial = parseFloat(document.getElementById('initial').value) || 0;
    const monthly = parseFloat(document.getElementById('monthly').value) || 0;
    const rateAnnual = parseFloat(document.getElementById('rate').value) || 0;
    const years = parseFloat(document.getElementById('years').value) || 0;

    const months = years * 12;
    const rateMonthly = (rateAnnual / 100) / 12;

    // Fórmula: A = P(1+r)^n + PMT [ ((1+r)^n - 1) / r ]
    let total = initial * Math.pow(1 + rateMonthly, months);
    
    if (rateMonthly > 0) {
        total += monthly * ((Math.pow(1 + rateMonthly, months) - 1) / rateMonthly);
    } else {
        total += monthly * months;
    }

    const formatter = new Intl.NumberFormat('pt-BR', { style: 'currency', currency: 'BRL' });

    document.getElementById('result-value').innerText = formatter.format(total);
    document.getElementById('result-details').innerText = `Projeção baseada em ${months} meses de aportes.`;
    document.getElementById('calc-result').style.display = 'block';
}