# #21356e

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

## Values

- Hex: `#21356e`
- RGB: rgb(33, 53, 110)
- HSL: hsl(224, 54%, 28%)
- OKLCH: oklch(0.346 0.102 266.5)
- Relative luminance: 0.04
- Nearest named color: Atlantic Navy (#13336f, Δ 1.654) — https://brandsweets.com/colors/atlantic-navy
- Moods: cool, dark, luxury, bold, modern
- Page: https://brandsweets.com/colors/21356e

## Tints & shades

- Tints (toward white): #294389, #3150a5, #395dc0, #5273cb, #6e89d4, #899fdc, #a5b6e4, #c0ccec, #dce2f4, #f7f9fd
- Shades (toward black): #1e3266, #1b2c5a, #192852, #152247, #131f3f, #101b37, #0d152b, #0b1123, #070b18, #050810

## Harmonies

- Complementary: #6e5921
- Analogous: #215c6e, #33216e
- Triadic: #6e2135, #356e21
- Split-complementary: #6e3321, #5c6e21
- Tetradic: #6e215c, #6e5921, #216e33

## Colors that go with #21356e

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 #21356e's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces. Seen in: Plaid (https://brandsweets.com/colors/brands/plaid-com), Glacier (https://brandsweets.com/palettes/cool#glacier), 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] — 10 real palettes, including Alaska Airlines's brand system and CVS's brand system put Blue beside #21356e, as the accent. Seen in: Alaska Airlines (https://brandsweets.com/colors/brands/alaskaair-com), CVS (https://brandsweets.com/colors/brands/cvs-com), Procter & Gamble (https://brandsweets.com/colors/brands/pg-com), Jeep (https://brandsweets.com/colors/brands/jeep-com). — https://brandsweets.com/colors/blue
- **Cadet Blue** #5f9ea0 [pool] — Designers have shipped Cadet Blue with #21356e: 5 real palettes, including Open House and Coastal, as the supporting colour. Seen in: Open House (https://brandsweets.com/palettes/clean#open-house), Coastal (https://brandsweets.com/palettes/cool#coastal), SoFi (https://brandsweets.com/colors/brands/sofi-com), Dusk (https://brandsweets.com/palettes/cool#dusk). — https://brandsweets.com/colors/cadetblue
- **Cobalt Blue** #0047ab [pool] — Designers have shipped Cobalt Blue with #21356e: 4 real palettes, including Purina Pro Plan's brand system and Blue Mono, as the accent. Seen in: Purina Pro Plan (https://brandsweets.com/colors/brands/chewy-com), Blue Mono (https://brandsweets.com/palettes/cool#blue-mono), Unilever (https://brandsweets.com/colors/brands/unilever-com), MLB (https://brandsweets.com/colors/brands/mlb-com). — https://brandsweets.com/colors/cobalt
- **Crimson** #dc143c [pool] — Crimson is paired with #21356e in 9 real palettes, including Casper Sleep's brand system and Marvel's brand system, as the lead colour. Seen in: Casper Sleep (https://brandsweets.com/colors/brands/casper-com), Marvel (https://brandsweets.com/colors/brands/marvel-com), Nintendo (https://brandsweets.com/colors/brands/nintendo-com), Frost & Ember (https://brandsweets.com/palettes/bold#frost-and-ember). — https://brandsweets.com/colors/crimson
- **Deep Sky Blue** #00bfff [pool] — Designers have shipped Deep Sky Blue with #21356e: 4 real palettes, including Lamborghini's brand system and Kraken's brand system, as the supporting colour. Seen in: Lamborghini (https://brandsweets.com/colors/brands/lamborghini-com), Kraken (https://brandsweets.com/colors/brands/kraken-com), Vimeo (https://brandsweets.com/colors/brands/vimeo-com), Astro (https://brandsweets.com/colors/brands/astro-build). — https://brandsweets.com/colors/deepskyblue
- **Denim** #1560bd [pool] — Designers have shipped Denim with #21356e: 20 real palettes, including Hasbro's brand system and Panasonic's brand system, as the supporting colour. Seen in: Hasbro (https://brandsweets.com/colors/brands/hasbro-com), Panasonic (https://brandsweets.com/colors/brands/panasonic-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 #21356e: 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): 11.67:1 — AA pass, AA-large pass, AAA pass
- On black (#000000): 1.8:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #5273cb (4.67:1); AA: background → #a1a1a1 (4.52:1); AAA: text → #7d96d8 (7.23:1); AAA: background → #c9c9c9 (7.05:1)

## Brands using this color

- **Casper Sleep** — accent #1e306e (Δ 1.539) — https://brandsweets.com/colors/brands/casper-com
- **Marvel** — secondary #223364 (Δ 1.762) — https://brandsweets.com/colors/brands/marvel-com

## Fonts for this mood

- luxury: https://brandsweets.com/fonts/mood/luxury
- bold: https://brandsweets.com/fonts/mood/bold
- 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/21356e-9ca2c4-df724e-221f2d-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: "#21356e" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.