50e2f970c8
Midnight is monotone in a way none of the other skins are, and it turns out to be a good test of the retint: its ring is `#8b80e8` under a `#ddd6ff` primary — the same violet at a different lightness, not a repeat of one hex. Matching accent slots by exact equality with the primary left that ring behind, so re-seeding produced a half-retinted theme with a purple ring under a teal accent. Slots now join the family by HUE, within a tolerance, and each keeps its own lightness and chroma when it moves. A theme that deliberately runs a deeper ring keeps that relationship instead of being flattened onto one colour. Near-greys are excluded by chroma rather than hue, so mono's neutral ring still stays exactly where its author put it.