How do you change the format of the header of a ctools modal window in Drupal?

I have a a standard ctools modal window. I开发者_开发问答 am able to style the header section title text, and customize that text, but I want to change the right side of the header which has "Close window" and an X icon.

Specifically, I want to use a different X icon and remove the text "Close window". How do I do this?

You can alter the settings in hook_preprocess_html function

drupal_add_js(array(
  'CToolsModal' => array(
    'closeImage' => theme('image', array(
      'path' => drupal_get_path('theme', 'mytheme') . ('/img/modal_close.png'),
      'title' => t('Close window'),
      'alt' => t('Close window'),
    )),
)), 'setting');

I created a new x icon and then went in to the ctools image folder and replaced the icon-close-window.png (the old x) with my new x.