Sumi palette
Crimson Deck
Five sumi stops with room to breathe — #8a1d00 grounds, #c83813 and #e85736 do the talking, #ee7356 softens, #ff9a81 lifts. The monochromatic bones keep it coherent across book covers that read at thumbnail size. The darkest and lightest stops clear AA as a text pair.
redsumifive-stophigh-contrast
#8a1d00
#c83813
#e85736
#ee7356
#ff9a81
The generator opens with #8a1d00 as the primary and the next two stops as secondary and accent — adjust, check contrast, and export tokens or CSS from there.