Javascript Menu is Stretched

hi,
I made a customize page and put a JavaScript Menu in it, but the menu is Stretched, link below:
http://huamaple.ca/ca1/blog3/?page_id=19

but the menu shows OK when I put it in a separate .PHP page on the root, http://huamaple.ca/ca1/blog3/menu.php

it also shows OK in another PHPBB forum folder,
http://huamaple.ca/tor/torviewforum.php

Anybody knows how to fix this “Menu Stretched” problem?

Is it in style.css problem ? or anything else?

thank you for your help.
Andy