Dark Convolvulus
Dark Convolvulus (#18256F) is a deep 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 (231°, 64%, 26%) places it in the balanced band at a dark lightness. It works well as a headline, icon, or deep background in an otherwise light layout, pairing cleanly with cream, bone, and warm neutrals. For a confident two-color system, pair it with its complementary amber. For something softer, pull in its analogous neighbors on either side of the wheel.
Etymology
Old English deorc, dark, gloomy — cognate with the German dunkel and the Latin terra, earth, both pointing to a base meaning of covered or obscured. As a color modifier, dark sits on the lightness axis only: it says nothing about hue or saturation, only that the value is low. Used across every adjective bucket the engine routes to when L < 0.40.
The genus Convolvulus — bindweed — including the saturated blue-flowered Mediterranean C. sabatius (ground morning-glory) of southern European rock gardens. The color refers to a fresh C. sabatius at peak summer bloom: a saturated, slightly cool deep blue with the satin finish of trumpet-shaped 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.