const colors = ["green", "red", "rgba(133,122,200)",
"#f15025", ];

const btn = document.getElementById('btn');
const color = document.querySelector(".color");

 btn.addEventListener('click', function(){
    // get random number between 0- 3
    const randomNumber = getRandomNumber();
    
    document.body.style.backgroundColor = colors[randomNumber];
    color.textContent = colors[randomNumber];
 });

 function getRandomNumber() {
    return Math.floor(Math.random() * colors.length);
  }



