title: How to increment or decrement height of a div using jquery
body: <p>This is my attempt to decrement by 28:</p>
  
  <pre><code>var addItemForm = $('.add-item-form');
  var h = addItemForm.height()-28;
  var h = toString(h);
  addItemForm.height(h);
  </code></pre>
  
  <p>But it doesn't work.</p>