title: Conversion of JQuery to Javascript code
body: <p>To find a DOM element and to traverse and to trigger the click event , I tried:</p>
  
  <pre><code> $("#intrusionGroup1").closest("div").children("div").children("ul").children("li").children("div").children("a").click(function () {
                  self.addIntrusion();
  
              });
  </code></pre>
  
  <p>I need to convert it to Javascript code base , but this did not work:</p>
  
  <pre><code>document.queryselector("#intrusionGroup1").closest("div").children(....)
  </code></pre>
  
  <p>It said <code>children</code> is not a function , even <code>find</code> is not a function.</p>
  
  <p>How to convert the same to Pure Javascript code?</p>