gitDisco.js

let disco, playing = false;
const dots = document.getElementsByTagName('rect');
const box = document.getElementsByTagName('g')[0];

const getRandomNumber = () => {
  return Math.floor(Math.random() * 255) + 1;
};

const getRandomCol = () => {
  return `rgb(${getRandomNumber()}, ${getRandomNumber()}, ${getRandomNumber()})`;
};

const gitDisco = () => {
  for (let i = 0; i < dots.length; i++) {
    dots[i].style.fill = getRandomCol();
  }  
};

const startDisco = () => {
  if (!playing) {
    playing = !playing;
    disco = setInterval(gitDisco, 500);
  } else {
    playing = !playing;
    clearInterval(disco);
  }
};

box.addEventListener('click', startDisco);