components-v0.1.4

Improve baseline CSS and package.json SEO

- Add site-only CSS variables for mono font, font sizes, spacing
- Apply monospace font to code elements
- Add demo area visual boundary (dashed border)
- Increase page-level margins and fix font sizes
- Add responsive layout for mobile (sidebar hidden, header wraps)
- Fix undefined --so-font-size-xs references
- Update package description and keywords for npm discoverability