2.15. Standards-compliant XHTML and CSS

Improves search engine visibility, reduce page weight, makes content accessible from all web browsers, regardless of capability.

Plone was the first 100% XHTML and CSS standards-compliant CMS in the world, and is based on open standards.

Plone degrades gracefully, and works on any device that supports HTML — including old browsers, cell phones and text-based browsers like Lynx — as well as screen readers used by the blind.