Cool palette generator

Generates palettes drawn from the cool arc — greens, blues and violets, roughly hue 160 through 280.

Cool palettes dominate software interfaces, and the reason is mostly about what they leave room for. Blue is the least emotionally loaded hue in most cultures, which makes it a safe default, and a cool ground makes any warm accent stand out sharply. The practical caution is that blues are where display calibration varies most, so a blue that looks right on your monitor can look noticeably different on a phone — worth checking on a second screen before committing. Cool colours also recede, which is useful for backgrounds and unhelpful for anything meant to be noticed.