Unlinked TOC items sidemenu styling help

[Lan_OZ]

Hi
In my TOC i am using unlinked items to act as menu dividers for my top nav menu so that a user can click on the item to open further grouped TOC items. This is working well for the nav menu however i have discovered that this means if another item in the menu is opened, i now have no way of accessing the other grouped items (see image which might help it make more sense.)
Does anyone have any suggestion on what CSS i can add to my stylesheet to make the items open either on hover or clicking aside from making them as actual topics, which i would rather not do. I have tried a few things but am still new to CSS so so far have had no success
Thank you
L