Sidebar Menu Scroller

Sidebar Menu Scroller

I am trying to develop Sidebar scroller (Its an Audit application), at the sidebar i want to give form question link which will be opened on side page as form so user can fill the form. I have got more than 1000 questions, wile selecting the question the side bar menu scroller need to get some specified color from both side.
eg: if i am selecting question 1.1.1 it need to get some color as highlight on both side of the scroller, i dont want entire link to be colored. 

Any help please.
Thanks.