CODE EXAMPLE FOR JAVASCRIPT

random color by EventListener click

const btn = document.querySelector('button');

function random(number) {
  return Math.floor(Math.random() * (number+1));
}

function changeBackground() {
  const rndCol = `rgb(${random(255)}, ${random(255)}, ${random(255)})`;
  document.body.style.backgroundColor = rndCol;
}

btn.addEventListener('click', changeBackground);