document.getElementById('login_form').onsubmit = function(e) {
    e.preventDefault();
    const user = document.getElementById('l_fld').value;
    const pass = document.getElementById('p_fld').value;

    // Encode credentials to Base64
    const authHeader = 'Basic ' + btoa(user + ':' + pass);

    fetch('/private/index.html', {
        method: 'GET',
        headers: { 'Authorization': authHeader }
    })
    .then(response => {
        if (response.ok) {
            window.location.href = '/private/'; // Redirect on success
        } else {
            alert('Invalid credentials'); // Handle error
        }
    });
};