Sumi palette
Breezy Square
From #90002f ink through #c33a54, #e3586e, #e97381 to #ff96a1 light, Breezy Square is a tetradic progression that holds together at any size. Use it for book covers that read at thumbnail size. The darkest and lightest stops clear AA as a text pair.
redsumifive-stophigh-contrast
#90002f
#c33a54
#e3586e
#e97381
#ff96a1
The generator opens with #90002f as the primary and the next two stops as secondary and accent — adjust, check contrast, and export tokens or CSS from there.