title: Using setTimeout in mouseenter and mouseleave events
body: <p>I have the following:</p>
  
  <pre><code>$("#header .navigation li.menu-item-first a").mouseenter(function() {
      $(".sub-nav").css("display", "block");
  }).mouseleave(function() {
      $(".sub-nav").css("display", "none");
  });
  </code></pre>
  
  <p>I don't want <code>.sub-nav</code> to disappear as soon as the user moves the mouse away.
  How would I integrate <code>setTimeout</code> into these?</p>