Cool Mustard Stream

#403e08

Notes

Cool Mustard Stream (#403E08) is a deep yellow 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 (58°, 78%, 14%) places it in the highly saturated band at a dark 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 blue. For something softer, pull in its analogous neighbors on either side of the wheel.

HEX

#403e08

RGB

rgb(64, 62, 8)

HSL

hsl(58, 78%, 14%)