using a [babel plugin](https://gist.github.com/pengx17/49e24ae8a5a609bdaff122ee8c679d1c) to transform all var(--affine-xxx) to cssVar
Some issues:
- tried ast-grep but it seems to be not easy to add imports conditionally
- current work does not work well with ts with types because babel will strip them out
Add color-scheme to html so that the web will use system scheme when scripts has not being loaded;
Use `(prefers-color-scheme: dark)` so that the css vars do not defer load based on `data-theme`, which is set by next-themes (which is deferred).
forehalo