I have a strange problem which I originally thought may be an overflow:hidden on the container, but turned out not to be. When a category is active (clicking on it and being in that category), its sub-menu will appear on-hover over the menu link. When it’s not, it won’t show.
For example go to the injuries page and try to hover over resources, the sub-menu doesn’t show! If you hover over injuries, the injuries sub-menu does. Vice versa happens when on the resource page.