# #313f77

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

## Values

- Hex: `#313f77`
- RGB: rgb(49, 63, 119)
- HSL: hsl(228, 42%, 33%)
- OKLCH: oklch(0.386 0.097 270.7)
- Relative luminance: 0.0554
- Nearest named color: Evening Magic (#363e7d, Δ 1.308) — https://brandsweets.com/colors/evening-magic
- Moods: cool, modern
- Page: https://brandsweets.com/colors/313f77

## Tints & shades

- Tints (toward white): #3b4c91, #4458a7, #5569b9, #6b7cc2, #8492cd, #9aa6d6, #b3bce0, #c9cfe9, #e2e5f3, #f8f9fc
- Shades (toward black): #2c396d, #283362, #232e57, #1f284c, #1c2445, #181f3a, #13192f, #0f1324, #0a0d19, #06080e

## Harmonies

- Complementary: #776931
- Analogous: #316277, #463177
- Triadic: #77313f, #3f7731
- Split-complementary: #774631, #627731
- Tetradic: #773162, #776931, #317746

## Colors that go with #313f77

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 #313f77's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces. Seen in: Glacier (https://brandsweets.com/palettes/cool#glacier), Plaid (https://brandsweets.com/colors/brands/plaid-com), Fintech Trust (https://brandsweets.com/palettes/cool#fintech-trust), Auth0 (https://brandsweets.com/colors/brands/auth0-com). — https://brandsweets.com/colors/steelblue
- **Blue** #0000ff [pool] — 5 real palettes, including Alaska Airlines's brand system and CVS's brand system put Blue beside #313f77, 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), Procter & Gamble (https://brandsweets.com/colors/brands/pg-com). — https://brandsweets.com/colors/blue
- **Crimson** #dc143c [pool] — Crimson is paired with #313f77 in 8 real palettes, including Marvel's brand system and Casper Sleep's brand system, as the accent. Seen in: Marvel (https://brandsweets.com/colors/brands/marvel-com), Casper Sleep (https://brandsweets.com/colors/brands/casper-com), Walgreens (https://brandsweets.com/colors/brands/walgreens-com), Frost & Ember (https://brandsweets.com/palettes/bold#frost-and-ember). — https://brandsweets.com/colors/crimson
- **Denim** #1560bd [pool] — Designers have shipped Denim with #313f77: 18 real palettes, including Hasbro's brand system and Hinge's brand system, as the supporting colour. Seen in: Hasbro (https://brandsweets.com/colors/brands/hasbro-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
- **Midnight Blue** #191970 [pool] — 15 real palettes, including Microsoft's brand system and First Snow put Midnight Blue beside #313f77, as the accent. Seen in: Microsoft (https://brandsweets.com/colors/brands/microsoft-com), First Snow (https://brandsweets.com/palettes/cool#first-snow), Plaid (https://brandsweets.com/colors/brands/plaid-com), Fintech Trust (https://brandsweets.com/palettes/cool#fintech-trust). — https://brandsweets.com/colors/midnightblue
- **Orange Red** #ff4500 [pool] — Orange Red is paired with #313f77 in 5 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
- **Powder Blue** #b0e0e6 [pool] — Designers have shipped Powder Blue with #313f77: 6 real palettes, including First Snow and Glacier, as the accent. Seen in: First Snow (https://brandsweets.com/palettes/cool#first-snow), Glacier (https://brandsweets.com/palettes/cool#glacier), Frost & Ember (https://brandsweets.com/palettes/bold#frost-and-ember), Macaron (https://brandsweets.com/palettes/light#macaron). — https://brandsweets.com/colors/powderblue
- **White Smoke** #f5f5f5 [role] — White Smoke is the surface for #313f77: 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): 9.96:1 — AA pass, AA-large pass, AAA pass
- On black (#000000): 2.11:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #6073be (4.69:1); AA: background → #b0b0b0 (4.59:1); AAA: text → #8896ce (7.3:1); AAA: background → #d9d9d9 (7.06:1)

## 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/313f77-9c9fc4-df7c4e-231f2d-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: "#313f77" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.