text: const colors = ["green", "red", "rgba(133, 122,200)","#f15025"];
  const btn = document.getElementById("btn");
  const color = document.querySelector(".color");
  
  //setup the event list
  btn.addEventListener('click', function(){
  
      // get random nuber between 0 - 3
      const randomNumber = getRandomNumber();
      console.log(randomNumber);
  
      document.body.style.backgroundColor = colors[randomNumber];color.textContent = colors[randomNumber];
  });
  
  function getRandomNumber() {
      return Math.floor(Math.random()*colors.length);
  }