Question about the lesson

Theme: http://drupal.org/project/wilderness

How to change the design of content in regions?

I have been searching for how to do this in page.tpl.php without success. How do the "artmenu" styles work for the "menu" region, but when I try to apply the same in the page.tpl.php file for another list, for example through <div>, it does not work correctly, specifically the menu items disappear? And what is this anomaly where if you remove the <div> tag and simply output  <?php echo $navigation; ?>, the items still remain, albeit with incomplete layout styles?

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