<div></div>

const appBackground = {backgroundParrent: document};

const backgroundArrayImg = [
  'https://placekitten.com/g/200/300',
  'https://placekitten.com/g/300/400',
  'https://placekitten.com/g/400/200',
];

let bgIndex = 0;
appBackground.backgroundParrent.addEventListener('click', () => {
  const url = backgroundArrayImg[(++bgIndex) % backgroundArrayImg.length];
  console.log(bgIndex);
  document.querySelector('body').style.backgroundImage = `url(${url})`;
});

document.querySelector('body').style.backgroundImage = `url(${backgroundArrayImg[bgIndex]})`;