title: Javascripts this.parentElement('div').classList.add Not working
body: <p>Just almost complete a project and this simple line won't allow me.</p>
  
  <pre><code>mykey= document.getElementById('mykey'),
  
  mykey.onclick = function() {this.parentElement('div').classList.add("green")};
  </code></pre>
  
  <p><strong>On click is not adding class 'green'</strong></p>
  
  <p>Any thought? </p>