Erebine Hibiscadelphus
Erebine Hibiscadelphus (#81021B) is a deep red 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 (348°, 97%, 26%) 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 teal. For something softer, pull in its analogous neighbors on either side of the wheel.
Etymology
Greek Erebine, of Erebus — adjectival form of Erebus, the primordial deity of darkness in Hesiod's Theogony. As a color modifier, erebine implies the deepest primordial-darkness of pre-cosmic chaos, with literary-cosmological register. Sits at the deepest-and-coolest end of the grid, parallel to Stygian and Cimmerian.
A genus of Hawaiian endemic hibiscus relatives — H. distans and H. giffardianus — whose deep red flowers are pollinated by Hawaiian honeycreepers. Most species are now extinct or critically endangered. The color refers to the petal of a fresh H. distans bloom: a saturated, slightly cool deep red with the satin finish of mallow-family flower.
Closest matches
The nearest named color in three reference sources, ranked by perceptual distance (ΔE76 in CIELAB). ΔE < 1 is imperceptible to most viewers; ΔE > 10 is clearly different. When two sources point to the same hex they’re merged into one tile; click any to open that color’s page.
Variations
Click any swatch to exploreHarmonies
Accessibility
How this color appears to viewers with the four major color-vision-deficiency types. Computed via the Machado (2009) physiologically-based model. If a tile matches the original, the color reads the same to that viewer.
The color used as foreground text against pure white and pure black, with the contrast ratio and WCAG 2.1 grade. Aim for AA (4.5:1) for body text and AA Large (3:1) for 18 pt+ headlines; AAA (7:1) is the gold standard for long-form reading surfaces.