Rich Cobalt Marble

#121aab

Notes

Rich Cobalt Marble (#121AAB) is a true blue with a jewel character. It carries the deep, saturated richness of a gemstone. Authoritative and slightly formal, it works well for type and heavy UI elements. Its HSL profile (237°, 81%, 37%) places it in the highly saturated band at a mid lightness. Best used in small doses, like logos, CTAs, focus rings, or highlight text, where its saturation becomes a feature rather than noise. For a confident two-color system, pair it with its complementary yellow. For something softer, pull in its analogous neighbors on either side of the wheel.

HEX

#121aab

RGB

rgb(18, 26, 171)

HSL

hsl(237, 81%, 37%)