Blue Hour palette
Cobalt Crater
Cobalt Crater runs #750d0a through #a14036, #bf5b4f, #c77165 to #e68c80 in five measured steps, the tetradic structure keeping every neighbor honest. Reach for it for book covers that read at thumbnail size. The darkest and lightest stops clear AA as a text pair.
redbluehourfive-stophigh-contrast
#750d0a
#a14036
#bf5b4f
#c77165
#e68c80
The generator opens with #750d0a as the primary and the next two stops as secondary and accent — adjust, check contrast, and export tokens or CSS from there.