Suggestion needed: Content Heavy Template?

Currently building an internal page with hundreds of PDF’s. It behoves me, but my end users are technological agnostic.

– Category
— SubCategory
---- Listing Page

I want this to look good, or user adoption will be 0. Managing the current system is a nightmare. Whereas, one must upload a document several time. horrrrrible!

Any suggestions to a good bootstrap/material design template that you may know about?

Thank you!