In the website that i am currently working on i have a pretty huge main menu, one of the items (products & services) has a sub menu with 6 columns which supposed to be rendered horizontally. but unfortunately some times it goes crazy, please see the attached photo below.

I think it because some of the CSS files are not loading properly some times, and i believe you can help me to fix this issue easily. this happens in all the web browsers i tested the site with, such as Safari, Firefox, Chorome and Opera.
Looking forward for your assistance,
Thank you and Best Regards,