`--accent` as the primary Button/active/focus source; legacy numbered
`primary-50` through `primary-950` tokens are intentionally not introduced.
- Hover and pressed primary states remain HeroUI-derived shades of `#DA241A`;
they never switch to a framework blue or purple.
- Charts use the shared 16-token Xinyuan palette (`--xinyuan-chart-1` through
`--xinyuan-chart-16`) and the `--rc-chart-*` aliases. The sequence is a
restrained brand-red, warm-neutral and slate-blue family with no green or
fluorescent colors. A single series always resolves to `#DA241A` and small
series sets use the first four brand-red steps.
- Light identity: `xy-logo-red.png`.
- Dark identity: `xy-logo-white.png`.
- Root theme: the application shell is explicitly `.light`; the content canvas stays light while the Sidebar consumes the fixed dark split-shell tokens.