0605:

<button> interakcja na stronie

<a> nawigacja

---

Nasłuchiwanie zdażeń:

element.addEventListener(type, listener [, options])
element.addEventListener('click', nazwaFunkcji);

Mouse events:

• click
• mouseenter
• mouseleave
• mouseover
• ...

const button = document.querySelector('.header__buton--js')
console.log(button)

function handleClick(){
  console.log('click')
}

button.addEventListener('click', handleClick);

const button = document.querySelector('.header__buton--js')
console.log(button)

button.addEventListener('click', (e) => {
  console.log('click2')
});

Event (e)

const header = document.querySelector('.header__title--js')
const headerContentBefore = header.innerHTML
const headerContentAfter = 'Zmiarna teści'
button.addEventListener('click', (e) => {
  if(header.innerHTML === headerContentBefore)
    header.innerHTML = headerContentAfter
  else
    header.innerHTML = headerContentBefore
});