Blue Hour palette
Polar Harbor
From #006487 ink through #0090c0, #38acde, #62bbe5 to #87d7ff light, Polar Harbor is a complementary progression that holds together at any size. Use it for book covers that read at thumbnail size. The darkest and lightest stops clear AA for large text.
cyanbluehourfive-stop
#006487
#0090c0
#38acde
#62bbe5
#87d7ff
The generator opens with #006487 as the primary and the next two stops as secondary and accent — adjust, check contrast, and export tokens or CSS from there.