colors
Back to gallery

Bastioned Plectranthus

#3b81d8
Notes

Bastioned Plectranthus (#3B81D8) is a true azure with a vibrant character. It holds its own as a focal accent, carrying visual weight without tipping into neon territory. Its HSL profile (213°, 67%, 54%) 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 orange. For something softer, pull in its analogous neighbors on either side of the wheel.

HEX
#3b81d8
RGB
rgb(59, 129, 216)
HSL
hsl(213, 67%, 54%)
HWB
hwb(213 23% 15%)
OKLCH
oklch(60.2% 0.150 255.4)
HSV
hsv(213, 73%, 85%)
LAB
lab(53.58% 7.27 -50.94)
LCH
lch(53.58% 51.46 278.12)
CMYK
cmyk(73%, 40%, 0%, 15%)

Etymology

Bastioned
adjective

Italian bastionato, fortified-with-bastions — past-participle of bastion, derived from bastia (fortified-tower). As a color modifier, bastioned implies a saturated-and-fortified-and-projecting quality, the deep-rich color of Vauban-period military-fortress star-fort projecting-bastion stone-architecture. Sits at the bold-and-fortified end of the grid, parallel to fortified and buttressed.

Plectranthus
noun

The genus Plectranthus — particularly P. ecklonii, the South African blue spur flower whose fall-blooming blue flower spikes attract sunbirds. The color refers to a fresh P. ecklonii at peak autumn bloom: a saturated, slightly cool deep blue-violet with the matte finish of small clustered mint-family flowers.

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 explore

Harmonies

Accessibility

Color-vision simulation

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.

#3b81d8
Original
#5888db
Protanopia
#3e79d6
Deuteranopia
#0095a2
Tritanopia
#787878
Achromatopsia
WCAG contrast

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.

The quick brown foxSample body text at normal size. The wcag minimum for body contrast is 4.5:1 (AA) or 7:1 (AAA).
AA Largeon White
3.95:1
The quick brown foxSample body text at normal size. The wcag minimum for body contrast is 4.5:1 (AA) or 7:1 (AAA).
AAon Black
5.32:1

Related Colors

Canvas