Blue Hour palette
Sloe Canyon
Dark anchor, working middle, light release: #a73f0b, #0066b6, #726600, #c65b2f, #2d82d4 form a tetradic blue hour set with somewhere to stand at every lightness. Made for book covers that read at thumbnail size.
orangebluehourfive-stop
#a73f0b
#0066b6
#726600
#c65b2f
#2d82d4
The generator opens with #a73f0b as the primary and the next two stops as secondary and accent — adjust, check contrast, and export tokens or CSS from there.