The CSS Working Group has published a Proposed Recommendation of CSS Writing Modes Level 3. This document defines CSS support for various writing modes and their combinations, including left-to-right and right-to-left text ordering as well as horizontal and vertical orientations. Comments are welcome through 22 November 2019.

CSS is a language for describing the rendering of structured documents (such as HTML and XML) on screen, on paper, etc.

Original source: https://www.w3.org/blog/news/archives/8010