Contents refinement

[ffoodd]

Several ways to improve documentation:

• new page / extend the home for usage: Sass, CSS, CDN, Sass modules, as a npm dep, etc.
• metadatas to filter tests: WCAG, RGAA, Opquast… Using some Nunjucks macro, could be handsome to add links automatically (to populate the references section, for example).
  • At least stop using URLs as links accesible names…
• improve layout to be more compact and appealing, e.g. maybe group Sass and CSS code blocks in tabs?

Anything else?