# #3f5488

A color — cool, modern. Deterministic analysis from BrandSweets (no inference).

## Values

- Hex: `#3f5488`
- RGB: rgb(63, 84, 136)
- HSL: hsl(223, 37%, 39%)
- OKLCH: oklch(0.454 0.089 266.3)
- Relative luminance: 0.0917
- Nearest named color: Dusk (#4e5481, Δ 2.319) — https://brandsweets.com/colors/dusk
- Moods: cool, modern
- Page: https://brandsweets.com/colors/3f5488

## Tints & shades

- Tints (toward white): #48609d, #546eb0, #6980ba, #7e92c4, #93a3cd, #a4b2d5, #b9c4df, #ced6e9, #e3e7f2, #f8f9fc
- Shades (toward black): #3a4d7e, #334570, #2f3e65, #283657, #232f4d, #1d273f, #182034, #121826, #0d111c, #06090e

## Harmonies

- Complementary: #88733f
- Analogous: #3f7888, #4f3f88
- Triadic: #883f54, #54883f
- Split-complementary: #884f3f, #78883f
- Tetradic: #883f78, #88733f, #3f884f

## Colors that go with #3f5488

Named partners (harmony on the OKLCH wheel, co-occurrence in curated palettes and brand systems, and the neutrals that carry it), best first:

- **Sea Green** #2e8b57 [harmony, pool: triadic] — Sea Green completes a triad with #3f5488 — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash. Seen in: Jack Daniel's (https://brandsweets.com/colors/brands/jackdaniels-com), Netflix (https://brandsweets.com/colors/brands/netflix), Paramount+ (https://brandsweets.com/colors/brands/paramountplus-com), Subaru (https://brandsweets.com/colors/brands/subaru-com). — https://brandsweets.com/colors/seagreen
- **Steel Blue** #4682b4 [harmony, pool: analogous] — Steel Blue is #3f5488's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces. Seen in: Capital One (https://brandsweets.com/colors/brands/capitalone-com), American Express (https://brandsweets.com/colors/brands/americanexpress-com), Auth0 (https://brandsweets.com/colors/brands/auth0-com), Glacier (https://brandsweets.com/palettes/cool#glacier). — https://brandsweets.com/colors/steelblue
- **Amber** #ffbf00 [pool] — Amber is paired with #3f5488 in 4 real palettes, including McDonald's's brand system and Warner Bros.'s brand system, as the lead colour. Seen in: McDonald's (https://brandsweets.com/colors/brands/mcdonalds-com), Warner Bros. (https://brandsweets.com/colors/brands/warnerbros-com), Lemon Squeezy (https://brandsweets.com/colors/brands/lemonsqueezy-com), Wikipedia (https://brandsweets.com/colors/brands/wikipedia-org). — https://brandsweets.com/colors/amber
- **Blue** #0000ff [pool] — 6 real palettes, including Tesco's brand system and CVS's brand system put Blue beside #3f5488, as the supporting colour. Seen in: Tesco (https://brandsweets.com/colors/brands/tesco-com), CVS (https://brandsweets.com/colors/brands/cvs-com), Activision (https://brandsweets.com/colors/brands/activision-com), Pixar (https://brandsweets.com/colors/brands/pixar-com). — https://brandsweets.com/colors/blue
- **Crimson** #dc143c [pool] — Crimson is paired with #3f5488 in 14 real palettes, including Walgreens's brand system and Wells Fargo's brand system, as the lead colour. Seen in: Walgreens (https://brandsweets.com/colors/brands/walgreens-com), Wells Fargo (https://brandsweets.com/colors/brands/wellsfargo-com), Costco (https://brandsweets.com/colors/brands/costco-com), Codecademy (https://brandsweets.com/colors/brands/codecademy-com). — https://brandsweets.com/colors/crimson
- **Firebrick** #b22222 [pool] — Designers have shipped Firebrick with #3f5488: 8 real palettes, including Campbell's's brand system and AT&T's brand system, as the supporting colour. Seen in: Campbell's (https://brandsweets.com/colors/brands/campbells-com), AT&T (https://brandsweets.com/colors/brands/att-com), Wendy's (https://brandsweets.com/colors/brands/wendys-com), Fireside (https://brandsweets.com/palettes/dark#fireside). — https://brandsweets.com/colors/firebrick
- **Goldenrod** #daa520 [pool] — Goldenrod shows up next to #3f5488 in 5 real palettes, including Open House and Sapphire & Gold, as the accent. Seen in: Open House (https://brandsweets.com/palettes/clean#open-house), Sapphire & Gold (https://brandsweets.com/palettes/luxury#sapphire-and-gold), Mid-Century (https://brandsweets.com/palettes/warm#mid-century), Fireside (https://brandsweets.com/palettes/dark#fireside). — https://brandsweets.com/colors/goldenrod
- **White Smoke** #f5f5f5 [role] — White Smoke is the surface for #3f5488: a clean near-white with no warm cast, so the cool hue stays clear instead of drifting muddy. — https://brandsweets.com/colors/whitesmoke

## Contrast (WCAG 2.x, as text)

- On white (#ffffff): 7.41:1 — AA pass, AA-large pass, AAA pass
- On black (#000000): 2.83:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #5b74b3 (4.59:1); AA: background → #cccccc (4.61:1); AAA: text → #8597c7 (7.25:1); AAA: background → #fafafa (7.1:1)

## Fonts for this mood

- modern: https://brandsweets.com/fonts/mood/modern

## Palette tool

Open this color locked as the lead with four explored companions: https://brandsweets.com/palettes/new/3f5488-9ca3c4-df704e-211f2d-e9eff1?lock=0&style=vibrant
(Humans lock/regenerate in the tool; the URL is the state — read `lock=` back to see what they kept.)

## Connect an agent

Point any MCP client at the BrandSweets colors endpoint for the same engine:

- Endpoint: https://mcp.brandsweets.com/colors/mcp
- Tools: `analyze_color` (e.g. `analyze_color({ color: "#3f5488" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.