index.js

const tabs = document.querySelectorAll('.tabs li');
const tabContentBoxes = document.querySelectorAll('#tab-content > div');
tabs.forEach((tab) => {
        tab.addEventListener('click', () => {
            tabs.forEach(item => item.classList.remove('is-active'))
            tab.classList.add('is-active');

            const target = tab.dataset.target;
            tabContentBoxes.forEach(box => {
            if(box.getAttribute('id') === target){
                box.classList.remove('is-hidden');
                }
            else{
                box.classList.add('is-hidden');
                }
            })
        })
    })

document.querySelector(".translation").addEventListener(
    'click', () => { document.getElementById("trans_eng")
    .classList.remove("is-hidden")
    document.querySelector(".translation").classList.add("is-hidden")}
)