Subframe. Graphite blueprint on warm vellum.

Subframe is a monochrome designer's workbench: warm off-white canvas, graphite-black ink, and zero chromatic accent. The entire interface reads as a single material — paper, pencil, and shadow — with one bold typographic gesture: a refined serif display (Instrument Serif) against a systematic sans (Inter) to give editorial gravity to the headlines. Surfaces are flat and bordered, not elevated; depth comes from hairline dividers in #e5e7eb and inset highlights on dark controls rather than drop shadows. Density is generous: wide vertical rhythm (48–64px section gaps), centered max-width layouts, and large breathing room around type. The only color is the contrast between near-white and near-black — making the dark filled button the single loudest element on every page, and the logo strip of grayscale partner brands the only decorative visual rhythm.