Refine CSS

- Denormalise sub and sup.
- Tweak header spacing
- Enhance list styles
- Remove redundant nav
- Fix style violations (one rule per line)
- Simplify headers
- Simplify responsiveness.
Update metadata

- fix viewpoint
- add charset data
Remove redundant navigation
Add category sections to introduction section.
Merge pull request #2 from JamieKnight/live-changes

Merge changes from live jkg3.com website.