# #3f4978

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

## Values

- Hex: `#3f4978`
- RGB: rgb(63, 73, 120)
- HSL: hsl(229, 31%, 36%)
- OKLCH: oklch(0.419 0.079 273.4)
- Relative luminance: 0.0718
- Nearest named color: Assassin (#2d4f83, Δ 2.908) — https://brandsweets.com/colors/assassin
- Moods: cool, muted
- Page: https://brandsweets.com/colors/3f4978

## Tints & shades

- Tints (toward white): #4a568c, #5462a0, #6976b0, #7d88ba, #919ac5, #a5adcf, #b9bfda, #d0d4e6, #e4e7f1, #f8f9fb
- Shades (toward black): #3a446e, #353d64, #2e3557, #282f4d, #232943, #1e2339, #191d2f, #121421, #0c0e17, #07080d

## Harmonies

- Complementary: #786e3f
- Analogous: #3f6678, #513f78
- Triadic: #783f4a, #4a783f
- Split-complementary: #78513f, #66783f
- Tetradic: #783f66, #786e3f, #3f7851

## Colors that go with #3f4978

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

- **Steel Blue** #4682b4 [harmony, pool: analogous] — Steel Blue is #3f4978's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces. Seen in: Auth0 (https://brandsweets.com/colors/brands/auth0-com), Capital One (https://brandsweets.com/colors/brands/capitalone-com), Glacier (https://brandsweets.com/palettes/cool#glacier), Fintech Trust (https://brandsweets.com/palettes/cool#fintech-trust). — https://brandsweets.com/colors/steelblue
- **Blue** #0000ff [pool] — 6 real palettes, including Alaska Airlines's brand system and CVS's brand system put Blue beside #3f4978, as the accent. Seen in: Alaska Airlines (https://brandsweets.com/colors/brands/alaskaair-com), CVS (https://brandsweets.com/colors/brands/cvs-com), Tesco (https://brandsweets.com/colors/brands/tesco-com), Jeep (https://brandsweets.com/colors/brands/jeep-com). — https://brandsweets.com/colors/blue
- **Crimson** #dc143c [pool] — Crimson is paired with #3f4978 in 11 real palettes, including Codecademy's brand system and Walgreens's brand system, as the accent. Seen in: Codecademy (https://brandsweets.com/colors/brands/codecademy-com), Walgreens (https://brandsweets.com/colors/brands/walgreens-com), Wells Fargo (https://brandsweets.com/colors/brands/wellsfargo-com), Marvel (https://brandsweets.com/colors/brands/marvel-com). — https://brandsweets.com/colors/crimson
- **Denim** #1560bd [pool] — Designers have shipped Denim with #3f4978: 14 real palettes, including HP's brand system and Hinge's brand system, as the accent. Seen in: HP (https://brandsweets.com/colors/brands/hp-com), Hinge (https://brandsweets.com/colors/brands/hinge-co), Jack Daniel's (https://brandsweets.com/colors/brands/jackdaniels-com), Starlink (https://brandsweets.com/colors/brands/starlink-com). — https://brandsweets.com/colors/denim
- **Goldenrod** #daa520 [pool] — Goldenrod shows up next to #3f4978 in 5 real palettes, including Sapphire & Gold and Open House, as the supporting colour. Seen in: Sapphire & Gold (https://brandsweets.com/palettes/luxury#sapphire-and-gold), Open House (https://brandsweets.com/palettes/clean#open-house), Disney (https://brandsweets.com/colors/brands/disney-com), Fireside (https://brandsweets.com/palettes/dark#fireside). — https://brandsweets.com/colors/goldenrod
- **Midnight Blue** #191970 [pool] — 15 real palettes, including First Snow and Microsoft's brand system put Midnight Blue beside #3f4978, as that palette's text colour. Seen in: First Snow (https://brandsweets.com/palettes/cool#first-snow), Microsoft (https://brandsweets.com/colors/brands/microsoft-com), FIFA (https://brandsweets.com/colors/brands/fifa-com), Fintech Trust (https://brandsweets.com/palettes/cool#fintech-trust). — https://brandsweets.com/colors/midnightblue
- **Orange Red** #ff4500 [pool] — Orange Red is paired with #3f4978 in 6 real palettes, including Tumblr's brand system and NASA's brand system, as the accent. Seen in: Tumblr (https://brandsweets.com/colors/brands/tumblr-com), NASA (https://brandsweets.com/colors/brands/nasa-gov), Tide (https://brandsweets.com/colors/brands/tide-com), HubSpot (https://brandsweets.com/colors/brands/hubspot-com). — https://brandsweets.com/colors/orangered
- **White Smoke** #f5f5f5 [role] — White Smoke is the surface for #3f4978: 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): 8.62:1 — AA pass, AA-large pass, AAA pass
- On black (#000000): 2.44:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #6573ae (4.62:1); AA: background → #bdbdbd (4.59:1); AAA: text → #8a94c1 (7.09:1); AAA: background → #e8e8e8 (7.04:1)

## Palette tool

Open this color locked as the lead with four explored companions: https://brandsweets.com/palettes/new/3f4978-9c9fc4-df7e4e-231f2d-e9eef1?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: "#3f4978" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.