index.js

let menuIcon = document.querySelector(".menu-icon");
let navlist = document.querySelector(".navlist")
menuIcon.addEventListener("click", () => {
    menuIcon.classList.toggle("active");
    navlist.classList.toggle("active");
    document.body.classList.toggle("open");
});

navlist.addEventListener("click", () => {
    navlist.classList.remove("active");
    menuIcon.classList.remove("active");
    document.body.classList.remove("open");
})

const buttons = document.querySelectorAll('.about-btn button');
const contents = document.querySelectorAll('.content');

buttons.forEach((button, index) => {
    button.addEventListener('click', () => {
        contents.forEach(content => content.style.display = 'none');
        contents[index].style.display = 'block';
        buttons.forEach(btn => btn.classList.remove('active'));
        button.classList.add('active');
    });
});