Child Category Not Showing In Main Menu

Currently working on a new site and my Main Menu is not showing any dropdown effects or child categories - nothing!

Looking at the source, all the elements are present, including those for the child dropdown categories , gk-menu.js is being included , but the menu is simply not dropping down and showing the child content!

I have tried disabling modules under the menu incase it is a layering issue, but this doesn't seem to be the case.

Everything seems to be set in admin for the menu to show - tried responsive both on and off.

Installed template override css which was suggested on another thread.

Going a lil' nuts here trying to figure this one out - has anyone else had a menu problem like this??

aaaarrrgh! Got it - and of course it was all down to me !

While working on the site design, I'd set

section#gkPageTop { overflow:hidden; }

changed it to visible and of course the child items became visible.

I am such a silly billy