Having some issues with top navigation when I include a script tag

Hey Guys,

I am having some issues with my wordpress top navigation bar. Whenever I add a javascript script tag either in the post or in the header file, my top nagivation bar messes up. For example, here is my site: https://seowebly.com/digital/, the top navigation bar is fine, but in the Adverisers tab, I have included a javascript lightbox script in the wordpress page but then the top navigation messes up. If I add the same script in the header.php file then the navigation of the entire site messes up. I have no clue as to why this happens. All I am trying to do is add these three lightbox js files:

<script type="text/javascript" src="js/prototype.js"></script>
<script type="text/javascript" src="js/scriptaculous.js?load=effects,builder"></script>
<script type="text/javascript" src="js/lightbox.js"></script>

Could someone please point me in the right direction.

Thanks,
Ket