E-book TOC and Bookmark Creation

I need a clickable Table of Contents for my ebook and epub.

Requirements:
- Minimalist style, simple and clean design.
- PDF should have a bookmarks panel (floating sidebar) that mimics the TOC.
- Epub should have a floating TOC.
- Two levels of headings (Chapters and sub-chapters).

Ideal skills:
- Experience with ebook formatting.
- Proficiency in creating interactive PDFs.
- Strong design skills for minimalist layouts.

This is the last step for my finished ebook. Looking forward to your bids!