2026-08-21 — Theme transition speed unify :: Website

Summary

Follow-up to theme toggle transition: document the shared --duration-theme / --ease-theme clock (~250ms ease-in-out) for site light/dark.

Theme token interpolation on html via @property remains the source of truth for surface colors.
A later pass (2026-09-13 — Theme transition surfaces unify) removes .dark gradient/shadow formula swaps that still snapped chrome and page glow off that clock.