title: How to increment the valueof the last span created with jQuery?
body: <p>I was looking for many solutions but I never (for now) found a solution.
  I would like to increment the value of the last span created by a click in a created li tag which is of course inside of an unordered list. </p>
  
  <p>Here is the HTML</p>
  
  <pre><code>&lt;input type="button" id="btn1" value="Add an Item"&gt;
  &lt;div id="cntn"&gt;
    &lt;ul class="tabs"&gt;
      &lt;li&gt;Item&lt;span class="listAdd"&gt;1&lt;/span&gt;&lt;/li&gt;
      &lt;li&gt;Item &lt;span class="listAdd"&gt;2&lt;/span&gt;&lt;/li&gt;
      &lt;li&gt;Item &lt;span class="listAdd"&gt;3&lt;/span&gt;&lt;/li&gt;
      &lt;li&gt;Item &lt;span class="listAdd"&gt;4&lt;/span&gt;&lt;/li&gt;
      &lt;li&gt;Item &lt;span class="listAdd"&gt;5&lt;/span&gt;&lt;/li&gt;
    &lt;/ul&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>and the iQuery</p>
  
  <pre><code>$(document).on('click','#btn1', function() {
    $("#cntn ul").append('&lt;li&gt;Item &lt;span class="listAdd"&gt;&lt;/span&gt;&lt;/li&gt;');
    $('.listAdd').append(Number($('.listAdd').text())+ 1);
  });
  </code></pre>
  
  <p>Basically, I would like to add a new list item with an incremented value in the span after clicking the button.
  If you can help me that would be amazing, I'm super stuck... Thank you!</p>