# #210308

A color — warm, vivid, dark, playful, bold, luxury. Deterministic analysis from BrandSweets (no inference).

## Values

- Hex: `#210308`
- RGB: rgb(33, 3, 8)
- HSL: hsl(350, 83%, 7%)
- OKLCH: oklch(0.166 0.055 12.6)
- Relative luminance: 0.0041
- Nearest named color: Belladonna (#220011, Δ 2.519) — https://brandsweets.com/colors/belladonna
- Moods: warm, vivid, dark, playful, bold, luxury
- Page: https://brandsweets.com/colors/210308

## Tints & shades

- Tints (toward white): #4b0712, #750b1c, #9f0f27, #c91331, #eb2445, #ef4e68, #f2788c, #f6a2b0, #faccd3, #fef6f7
- Shades (toward black): #210308, #1c0307, #1c0307, #1c0307, #1c0307, #170206, #170206, #170206, #130205, #130205

## Harmonies

- Complementary: #03211c
- Analogous: #210317, #210d03
- Triadic: #082103, #030821
- Split-complementary: #03210d, #031721
- Tetradic: #172103, #03211c, #0d0321

## Colors that go with #210308

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

- **Charcoal** #36454f [role, pool] — Charcoal is the body-text near-black for #210308: its slight blue cast keeps type crisp beside a warm colour where pure #000 looks heavy. Seen in: Asana (https://brandsweets.com/colors/brands/asana-com), Bloomberg (https://brandsweets.com/colors/brands/bloomberg-com), Codecademy (https://brandsweets.com/colors/brands/codecademy-com), dbt Labs (https://brandsweets.com/colors/brands/getdbt-com). — https://brandsweets.com/colors/charcoal
- **Denim** #1560bd [harmony, pool: triadic] — Denim completes a triad with #210308 — three hues spaced evenly round the wheel, the classic way to get energy into a palette without a clash. Seen in: American Express (https://brandsweets.com/colors/brands/americanexpress-com), Apple (https://brandsweets.com/colors/brands/apple-com), Coursera (https://brandsweets.com/colors/brands/coursera-org), Dell (https://brandsweets.com/colors/brands/dell-com). — https://brandsweets.com/colors/denim
- **Sea Green** #2e8b57 [harmony, pool: split] — Sea Green is a split-complement of #210308: nearly opposite, so it still pops against it, without the vibrating edge of a true complement. Seen in: Asana (https://brandsweets.com/colors/brands/asana-com), Lemon Squeezy (https://brandsweets.com/colors/brands/lemonsqueezy-com), Coinbase (https://brandsweets.com/colors/brands/coinbase), Next.js (https://brandsweets.com/colors/brands/nextjs-org). — https://brandsweets.com/colors/seagreen
- **Sienna** #a0522d [harmony, pool: analogous] — Sienna is #210308's neighbour on the wheel, so the two read as one family — use it for hover states, gradients and secondary surfaces. Seen in: Oatly (https://brandsweets.com/colors/brands/oatly-com), Coffee Bar (https://brandsweets.com/palettes/dark#coffee-bar), Woodsmoke (https://brandsweets.com/palettes/dark#woodsmoke), BrandSweets (https://brandsweets.com/colors/brands/brandsweets). — https://brandsweets.com/colors/sienna
- **Teal** #008080 [harmony, pool: complementary] — Teal sits directly opposite #210308 on the wheel — the strongest contrast one hue can give another, so use it small: a button, a link colour, one highlight. Seen in: Redfin (https://brandsweets.com/colors/brands/redfin-com), Gemstone (https://brandsweets.com/palettes/vivid#gemstone), Magazine Ochre (https://brandsweets.com/palettes/editorial#magazine-ochre), Gusto (https://brandsweets.com/colors/brands/gusto-com). — https://brandsweets.com/colors/teal
- **Amber** #ffbf00 [pool] — Amber is paired with #210308 in 16 real palettes, including Ember and Heatwave, as the accent. Seen in: Ember (https://brandsweets.com/palettes/bold#ember), Heatwave (https://brandsweets.com/palettes/warm#heatwave), Ahrefs (https://brandsweets.com/colors/brands/ahrefs-com), Mastodon hosted on mastodon.social (https://brandsweets.com/colors/brands/mastodon-social). — https://brandsweets.com/colors/amber
- **Blue** #0000ff [pool] — 19 real palettes, including Robinhood's brand system and native Cybersecurity's brand system put Blue beside #210308, as the supporting colour. Seen in: Robinhood (https://brandsweets.com/colors/brands/robinhood-com), native Cybersecurity (https://brandsweets.com/colors/brands/crowdstrike-com), EA (https://brandsweets.com/colors/brands/ea-com), Penpot (https://brandsweets.com/colors/brands/penpot-app). — https://brandsweets.com/colors/blue
- **Blue Violet** #8a2be2 [pool] — Blue Violet is paired with #210308 in 10 real palettes, including Twitch's brand system and Neobank, as the lead colour. Seen in: Twitch (https://brandsweets.com/colors/brands/twitch-tv), Neobank (https://brandsweets.com/palettes/vivid#neobank), Render (https://brandsweets.com/colors/brands/render-com), Prepare your taste buds... (https://brandsweets.com/colors/brands/grubhub-com). — https://brandsweets.com/colors/blueviolet

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

- On white (#ffffff): 19.42:1 — AA pass, AA-large pass, AAA pass
- On black (#000000): 1.08:1 — AA fail, AA-large fail, AAA fail. Fix: AA: text → #e91639 (4.64:1); AA: background → #7a7a7a (4.52:1); AAA: text → #f16a80 (7.11:1); AAA: background → #9c9c9c (7.07:1)

## Fonts for this mood

- warm: https://brandsweets.com/fonts/mood/warm
- playful: https://brandsweets.com/fonts/mood/playful
- bold: https://brandsweets.com/fonts/mood/bold
- luxury: https://brandsweets.com/fonts/mood/luxury

## Palette tool

Open this color locked as the lead with four explored companions: https://brandsweets.com/palettes/new/210308-c49c9e-62cb87-2d231f-f1e9ee?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: "#210308" })`), `check_contrast` (with fixes), `generate_palette` (explore around locks), `suggest_palette` (mood/industry → curated-first), `list_palettes`.