Can the page be white?
No. The page is always sand — sand-100 where people read, sand-50 where they work — and white sections and cards sit on top of it.
The difference between the ground and what sits on it is what gives the page its hierarchy and lets it breathe.
What this answer rests on
constitutional/colour-is-the-aleris-palette.md§ 2. The non-negotiables Acceptedbaseline/BASELINE.md§ Hard rules Acceptedbaseline/BASELINE.md§ Surface temperature Acceptedprinciples/colour.md§ Hard rules Accepted