A monospace grid is the cheapest layout system in existence. Every glyph is the same width, so columns line up for free, ASCII diagrams stay square, and you can reason about a page the way you reason about a terminal.
+----------------+ +----------------+
| content/*.md | ----> | dist/*.html |
+----------------+ build +----------------+
You don't need a design system when the grid is the design. That's the whole bet this site makes.