# #3d517b

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

## Values

- Hex: `#3d517b`
- RGB: rgb(61, 81, 123)
- HSL: hsl(221, 34%, 36%)
- OKLCH: oklch(0.438 0.074 264.2)
- Relative luminance: 0.0831
- Nearest named color: Assassin (#2d4f83, Δ 2.466) — https://brandsweets.com/colors/assassin
- Moods: cool, muted
- Page: https://brandsweets.com/colors/3d517b

## Tints & shades

- Tints (toward white): #475e90, #516ba4, #657eb3, #7a8fbd, #8ea0c7, #a3b2d2, #b7c3dc, #cfd7e7, #e4e8f2, #f8f9fc
- Shades (toward black): #384a71, #324367, #2c3a59, #27334f, #222d44, #1d263a, #181f30, #111622, #0c1018, #07090e

## Harmonies

- Complementary: #7b673d
- Analogous: #3d707b, #483d7b
- Triadic: #7b3d50, #507b3d
- Split-complementary: #7b483d, #707b3d
- Tetradic: #7b3d70, #7b673d, #3d7b48

## Colors that go with #3d517b

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 #3d517b — 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), Subaru (https://brandsweets.com/colors/brands/subaru-com), Netflix (https://brandsweets.com/colors/brands/netflix), Paramount+ (https://brandsweets.com/colors/brands/paramountplus-com). — https://brandsweets.com/colors/seagreen
- **Steel Blue** #4682b4 [harmony, pool: analogous] — Steel Blue is #3d517b'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), Auth0 (https://brandsweets.com/colors/brands/auth0-com), Glacier (https://brandsweets.com/palettes/cool#glacier), American Express (https://brandsweets.com/colors/brands/americanexpress-com). — https://brandsweets.com/colors/steelblue
- **Blue** #0000ff [pool] — 7 real palettes, including CVS's brand system and Tesco's brand system put Blue beside #3d517b, as the supporting colour. Seen in: CVS (https://brandsweets.com/colors/brands/cvs-com), Tesco (https://brandsweets.com/colors/brands/tesco-com), Alaska Airlines (https://brandsweets.com/colors/brands/alaskaair-com), Activision (https://brandsweets.com/colors/brands/activision-com). — https://brandsweets.com/colors/blue
- **Cadet Blue** #5f9ea0 [pool] — Designers have shipped Cadet Blue with #3d517b: 4 real palettes, including Dusk and Open House, as the supporting colour. Seen in: Dusk (https://brandsweets.com/palettes/cool#dusk), Open House (https://brandsweets.com/palettes/clean#open-house), Alpine (https://brandsweets.com/palettes/cool#alpine), Paper & Pine (https://brandsweets.com/palettes/minimal#paper-and-pine). — https://brandsweets.com/colors/cadetblue
- **Cornflower Blue** #6495ed [pool] — Designers have shipped Cornflower Blue with #3d517b: 4 real palettes, including Blizzard's brand system and Blue Mono, as the lead colour. Seen in: Blizzard (https://brandsweets.com/colors/brands/blizzard-com), Blue Mono (https://brandsweets.com/palettes/cool#blue-mono), Coca-Cola (https://brandsweets.com/colors/brands/coca-cola-com), Gopro (https://brandsweets.com/colors/brands/gopro-com). — https://brandsweets.com/colors/cornflowerblue
- **Crimson** #dc143c [pool] — Crimson is paired with #3d517b in 13 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), Costco (https://brandsweets.com/colors/brands/costco-com). — https://brandsweets.com/colors/crimson
- **Denim** #1560bd [pool] — Designers have shipped Denim with #3d517b: 16 real palettes, including HP's brand system and Dutch Bros's brand system, as the accent. Seen in: HP (https://brandsweets.com/colors/brands/hp-com), Dutch Bros (https://brandsweets.com/colors/brands/dutchbros-com), Hinge (https://brandsweets.com/colors/brands/hinge-co), Jack Daniel's (https://brandsweets.com/colors/brands/jackdaniels-com). — https://brandsweets.com/colors/denim
- **White Smoke** #f5f5f5 [role] — White Smoke is the surface for #3d517b: 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): 7.89:1 — AA pass, AA-large pass, AAA pass
- On black (#000000): 2.66:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #5b75ae (4.6:1); AA: background → #c4c4c4 (4.52:1); AAA: text → #8195c1 (7:1); AAA: background → #f2f2f2 (7.05:1)

## Palette tool

Open this color locked as the lead with four explored companions: https://brandsweets.com/palettes/new/3d517b-9ca4c4-df6b4e-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: "#3d517b" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.