clear content of the div tag by javascript

How to clear the contents of the div tag through javascript when click the close button?.

This is the full code in header.

<script type="text/javascript">
    jQuery(document).ready(function($) {
      $('a[rel*=facebox]').facebox({
        loading_image : 'loading.gif',
        close_image   : 'closelabel.gif'
      }) 
    })
  </script>

Code (markup):

Contents:

<a href="#mobile" rel="facebox">
<img src="mobile.png">
</a>
<div id="mobile" style="display:none;">
Dynamic content by php code.
</div>

Code (markup):

 

find the class that goes on the image and set up a click listener then $("#mobile").html("");

 

Iam not expert in javascript. I have added like below

<script type="text/javascript">
    jQuery(document).ready(function($) {
      $('a[rel*=facebox]').facebox({
        loading_image : 'loading.gif',
        close_image   : 'closelabel.gif'
$("#mobile").html(""); 
      }) 
    })
  </script>

Code (markup):

Is it right?

 

nope..

it should be...

<script type="text/javascript">
    jQuery(document).ready(function($) {
      $('a[rel*=facebox]').facebox({
        loading_image : 'loading.gif',
        close_image   : 'closelabel.gif' 
      });
      $("#mobile").html("");
    })
  </script>

Code (markup):

 

Iam getting blank display box with close image button.