text: var closedFace = document.querySelector('.closed')
  var openFace = document.querySelector('.open')
  
  //add event listener #1:
  closedFace.addEventListener('click', () => {
      if(openFace.classList.contains('open')) {
         openFace.classList.add('active');
         closedFace.classList.remove('active');
         console.log("user clicked the closed face");
      }
  })
  
  //add event listener #2:
  openFace.addEventListener('click', () => {
      if(closedFace.classList.contains('closed')) {
          closedFace.classList.add('active');
          openFace.classList.remove('active');
          console.log("user clicked open face");
      }
  });