Hi guys, 

I need your help. 

We are planning to transit into Lightning from classic recently. We have a visualforce page always bugging this transit - in this page, jQuery $ is used to validate user's input on this page. 

It feels like Lightning deprecated DOM, which makes this method impossible. 

I read something called "LockerService" to help me continue with the process, but it's for Lighning components instead of pages -- maybe I'll have to re-write the whole page. Not feasible.

Any idea to smooth this transit?

Thank you a lot in advance.