Unyielding Hibiscadelphus
Unyielding Hibiscadelphus (#D5435C) is a true red with a warm character. It leans warm, pulling light toward red, orange, and yellow. Naturally inviting, it suits editorial and hospitality contexts. Its HSL profile (350°, 63%, 55%) places it in the balanced band at a mid lightness. It works across type, buttons, and borders, saturated enough to feel deliberate but balanced enough to not fight the rest of the palette. 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
Old English un- (negation) plus gildan (to give-up). As a color modifier, unyielding implies a saturated-and-uncompromising quality where the hue refuses to fade-or-shift under any visual pressure. Sits at the bold-and-resilient end of the grid, parallel to indomitable and adamant in usage.
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.
Wide gamut
The CSS Color 4 wide-gamut form of this color. Both swatches render the same color on every display — the P3 form only diverges from sRGB when a designer pushes channels outside sRGB's reach.
This color is chromatic enough that authoring it as P3 native (instead of clamping to sRGB) gives a perceptibly more saturated render on wide-gamut displays — modern Macs, iPhones, iPads, and most recent OLED laptops.