Types and checks for every property are generated from mdn-data and @webref/css by packages/css-grammar (bun run extract), not written by hand, so a new property or function needs no change here. 536 members: 525 properties (every standard and experimental one, except the three shorthands above) and the 11 short names.
Browser support comes from @mdn/browser-compat-data against browserslist, as build warnings (see above). There is no per-property table in the types.
Not in 0.1: pseudo-elements, :has(), derived tokens, slot variants, a typed runtime token setter, icons (the plugin API they are written on is above; frame() is in cssints/frame, surface() in cssints/surface), polyfills of its own for missing browser features. The map and the reasons are in wayfinder.md.