Colorbox is interfering with mobile menu style. NEED HELP ASAP PLEASE!!! My current cart I am replacing went out of business so I can't make changes.

I have narrowed it down to the Colorbox. I can turn it off in admin and I don't have this issue. when using the mobile version as soon as I get to the product info page, my menu looses the css style and just shows a bunch of links.

I have 1.5.5f and 2.1.2 colorbox installed. I also have mega menu installed and use this code below to hide it in responsive.css and responsive_mobile.css so it blocks mega menu in mobile. Should I use this elsewhere or something different?

@media (min-width:0px) and (max-width:480px){ #mega-wrapper { display:none;visibility:hidden; }

Here is my site:
https://www.uesakausa.com

Here is where the colorbox is blocking the style.

https://www.uesakausa.com/index.php?...19ga23f74m0t01

I can not figure out what is happening on this page and why colorbox is blocking the styles. Need to get this Zen Cart up and running so I can move it to the main server and replace the site before it crashes. Thanking you in advance!