The logo is navy and bronze, not black and gold. The system keeps that distinction and widens it. Registry Navy, drawn from the W, does the work black usually does: text, statement fields, primary actions. Bronze is reserved for the mark, for 1 px rules and for a few moments of emphasis; it never fills a button and never becomes metallic outside the logo itself.
Grounds are gallery neutrals, measured to sit just off white with almost no chroma, so photography and property data carry the color. The names come from the materials of New England civic buildings: granite, slate, limestone, plaster.
Every value is defined in OKLCH so lightness steps are perceptually even and contrast is predictable. Hex values are the fallback for older browsers and for vendors.