Buttoned Sheet Denim
Buttoned Sheet Denim (#3A558C) is a true azure 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 (220°, 41%, 39%) 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 amber. For something softer, pull in its analogous neighbors on either side of the wheel.
Etymology
Old French bouton, button — past-participle of button. As a color modifier, buttoned implies a clear-and-fastened-and-formal quality, the crisp color of Edwardian-period formal-attire fully-fastened-and-formally-dressed gentleman's-attire. Sits at the crisp-and-finished end of the grid, parallel to trim and pressed in usage.
Old English scēate, rope-attached-to-sail. As a color modifier, sheet implies a rope-attached-to-sail-corner quality, the visual register of Tall-Ship-and-yacht-sheet hand-tied rope-attached-to-sail-corner mainsheet-and-jibsheet maritime-rigging surfaces under tall-ship-sheet-and-mainsheet maritime-rigging light. Sits at the modifier-and-nautical end of the grid, parallel to knot and sail in usage.
The diagonal-twill cotton fabric originally woven in Nîmes, France — serge de Nîmes, contracted to denim — and dyed with indigo since at least the eighteenth century. The color refers to a worn but un-faded pair of raw denim jeans: a saturated, slightly muted blue with the matte finish of cotton fiber that has absorbed dye through generations of weft and warp. Cooler than royal, warmer than navy.
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.
Moderately saturated colors gain a small bump in P3 — the difference is usually visible side-by-side on wide-gamut hardware but won't change the character of the color.