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Senatorial Blueprint

#3678ea
Notes

Senatorial Blueprint (#3678EA) 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 (218°, 81%, 56%) places it in the highly saturated band at a mid lightness. Best used in small doses, like logos, CTAs, focus rings, or highlight text, where its saturation becomes a feature rather than noise. 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.

HEX
#3678ea
RGB
rgb(54, 120, 234)
HSL
hsl(218, 81%, 56%)
HWB
hwb(218 21% 8%)
OKLCH
oklch(59.2% 0.185 260.5)
HSV
hsv(218, 77%, 92%)
LAB
lab(52.01% 18.80 -63.58)
LCH
lch(52.01% 66.30 286.47)
CMYK
cmyk(77%, 49%, 0%, 8%)

Etymology

Senatorial
adjective

Latin senātōrius, of the senator — adjectival suffix. As a color modifier, senatorial implies a saturated-and-aristocratic-and-Roman-Republic quality, the deep-rich color of Roman-Senate toga praetexta purple-bordered ceremonial-citizen-class livery. Sits at the bold-and-aristocratic end of the grid, parallel to patrician and imperial.

Blueprint
noun

The cyanotype reproduction process — invented by John Herschel in 1842 — used for architectural and engineering drawings until digital reproduction replaced it in the late twentieth century. Blueprint color refers to a fresh cyanotype print: a saturated, slightly cool deep blue with the matte finish of iron-cyanide-on-paper.

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.

#3678ea
Original
#3485ee
Protanopia
#0074e8
Deuteranopia
#0093a6
Tritanopia
#727272
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
4.17:1
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
5.03:1

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