Builds the --mj-* custom-property map applied to the host element. Keys are normalised so a page may
pass either brand-primary or --mj-brand-primary; both land as --mj-brand-primary. Values are passed
through verbatim (colours, radii, spacing) — the widget never synthesises a colour, so light/dark parity
is preserved. Anything malformed is dropped, not guessed at.
Builds the
--mj-*custom-property map applied to the host element. Keys are normalised so a page may pass eitherbrand-primaryor--mj-brand-primary; both land as--mj-brand-primary. Values are passed through verbatim (colours, radii, spacing) — the widget never synthesises a colour, so light/dark parity is preserved. Anything malformed is dropped, not guessed at.