Sumi palette
Topaz Prairie
Five sumi stops with room to breathe — #9b002a grounds, #b5233c and #007477 do the talking, #d54455 softens, #009195 lifts. The monochromatic bones keep it coherent across book covers that read at thumbnail size.
redsumifive-stop
#9b002a
#b5233c
#007477
#d54455
#009195
The generator opens with #9b002a as the primary and the next two stops as secondary and accent — adjust, check contrast, and export tokens or CSS from there.