Foundational Nimbus
Foundational Nimbus (#708484) is a true cyan with an earthy character. It leans grounded and natural, the kind of color that plays well with wood, clay, linen, and warm neutrals. Its HSL profile (180°, 8%, 48%) places it in the muted 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 red. For something softer, pull in its analogous neighbors on either side of the wheel.
Etymology
Latin fundātiō, foundation — adjectival suffix -al. As a color modifier, foundational implies a neutral-and-base-and-supporting quality where the hue carries the visual register of Bauhaus-and-Mondrian-De-Stijl foundational-and-base-supporting-color theoretical-color-system. Sits at the neutral-and-foundational end of the grid, parallel to primary and essential in usage.
The Latin meteorological term for rain cloud — particularly the dense, dark nimbostratus layer that brings sustained precipitation rather than convective bursts. The color refers to a fully developed nimbostratus deck: a soft, slightly muted dark gray with the optical density of a cloud already releasing rain. Cooler than smoke, warmer than slate, with the meteorological weight of a sky color that defines an entire weather pattern.
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 sits well within the sRGB cube. P3 and sRGB share the gray axis and most desaturated tones, so a P3 display renders this identically to an sRGB display.