Add css for other media such as print

[kinow]

Refs:

• https://iangmcdowell.com/blog/posts/laying-out-a-book-with-css/
• https://github.com/BafS/Gutenberg
• https://pagedjs.org/documentation/
• https://www.print-css.rocks/
• https://doc.courtbouillon.org/weasyprint/stable/

Note: keep it accessible (a11y).