text: // Don't change or delete this line! It waits until the DOM has loaded, then calls
  // the start function. More info:
  // https://developer.mozilla.org/en-US/docs/Web/Events/DOMContentLoaded
  document.addEventListener('DOMContentLoaded', start)
  
  function start () {
    // The first example is done for you. This will change the background colour of the first div
    // when you mouse over it.
    one()
    two()
    three()
    four()
  // Your turn! Create a new function called `two`, then call it from here.
  }
  
  function one () {
    // First, we have to find the element:
    var one = document.getElementById('one')
  
    // Next, we add an event listener to it:
    one.addEventListener('mouseenter', makeBlue)
  
    // Finally, we add one to make the colour white again
    one.addEventListener('mouseleave', makeWhite)
  }
  // CREATE FUNCTION two HERE
  function two() {
    var two = document.getElementById('two')
    two.addEventListener('mouseenter', makeGreen)
    two.addEventListener('mouseleave', makeWhite)
  }
  // CREATE FUNCTION three HERE
  function three() {
    var three = document.getElementById('three')
    three.addEventListener('mouseenter', makeRed)
    three.addEventListener('mouseleave', makeWhite)
  
  }
  // CREATE FUNCTION four HERE
  function four() {
    var four = document.getElementById('four')
    four.addEventListener('click', makeBlack)
    four.addEventListener('mouseleave', makeWhite)
  
  }
  // Changes the background color of event's target
  function makeBlue (evt) {
    evt.target.style.backgroundColor = 'blue'
  }
  
  function makeWhite (evt) {
    evt.target.style.backgroundColor = 'white'
  }
  
  function makeGreen (evt) {
  evt.target.style.backgroundColor = 'green'
  }
  
  
  function makeRed (evt) {
    evt.target.style.backgroundColor = 'red'
  }
  
  function makeBlack (evt) {
    evt.target.style.backgroundColor = 'black'
  }
  