# Spectrum gradient

Gradients derived from Spectrum's published colour tokens (nominative use; no brand assets). Deterministic: the same values are served as `--brand-gradient*` in the brand's brand.css.

- Page: https://brandsweets.com/gradients/brands/spectrum-com
- Brand colors: https://brandsweets.com/colors/brands/spectrum-com · Brand page: https://brandsweets.com/b/spectrum-com
- Palette: primary #1a1a1a, secondary #00194a, accents #005eff
- Source: https://spectrum.com (extracted 2026-09-05)

## Brand gradient

ΔE_OK 0.098 < 0.15 between #1a1a1a and #00194a — a 2-stop would read as a flat fill, so this is a tonal ramp of #1a1a1a.

- CSS: `linear-gradient(135deg in oklch shorter hue, #474747 0%, #1a1a1a 50%, #000000 100%)`
- Tailwind: `bg-linear-to-br/oklch from-[#474747] via-[#1a1a1a] to-[#000000]`
- Contrast (worst point): white 9.29:1 AA · black 1.00:1 fail · banding medium
- Maker: https://brandsweets.com/gradients/new/v1.474747-1a1a1a-000000?a=135&in=oklch&hue=shorter

## Hero background

Chroma ×0.35 so it can carry text; ink white (inkFor at the midpoint). Passes AA for that ink at the worst point (9.29:1) without adjusting L.

- CSS: `linear-gradient(135deg in oklch shorter hue, #474747 0%, #1a1a1a 50%, #000000 100%)`
- Tailwind: `bg-linear-to-br/oklch from-[#474747] via-[#1a1a1a] to-[#000000]`
- Contrast (worst point): white 9.29:1 AA · black 1.00:1 fail · banding medium · ink #ffffff
- Maker: https://brandsweets.com/gradients/new/v1.474747-1a1a1a-000000?a=135&in=oklch&hue=shorter

## Button / CTA

ΔL 0.08 top→bottom in the primary's hue (a lit surface, not a rainbow); hover L +0.03, active L −0.03. White ink passes AA on the surface and both states (worst 14.16:1).

- CSS: `linear-gradient(180deg in oklch shorter hue, #232323 0%, #111111 100%)`
- Tailwind: `bg-linear-to-b/oklch from-[#232323] to-[#111111]`
- Contrast (worst point): white 15.72:1 AA · black 1.11:1 fail · banding high · ink #ffffff
- Maker: https://brandsweets.com/gradients/new/v1.232323-111111?a=180&in=oklch&hue=shorter
- Hover: `linear-gradient(180deg in oklch shorter hue, #2b2b2b 0%, #181818 100%)`
- Active: `linear-gradient(180deg in oklch shorter hue, #1c1c1c 0%, #0b0b0b 100%)`

## Tonal ramp

- CSS: `linear-gradient(135deg in oklch shorter hue, #474747 0%, #1a1a1a 50%, #000000 100%)`
- Tailwind: `bg-linear-to-br/oklch from-[#474747] via-[#1a1a1a] to-[#000000]`
- Contrast (worst point): white 9.29:1 AA · black 1.00:1 fail · banding medium
- Maker: https://brandsweets.com/gradients/new/v1.474747-1a1a1a-000000?a=135&in=oklch&hue=shorter

## Analogous

Primary #1a1a1a is achromatic — harmony rotates #00194a instead. Partner hue from the analogous rule at the source colour's lightness.

- CSS: `linear-gradient(135deg in oklab, #00194a 0%, #00212f 100%)`
- Tailwind: `bg-linear-to-br/oklab from-[#00194a] to-[#00212f]`
- Contrast (worst point): white 16.62:1 AA · black 1.24:1 fail · banding high
- Maker: https://brandsweets.com/gradients/new/v1.00194a-00212f?a=135

## Complementary

Primary #1a1a1a is achromatic — harmony rotates #00194a instead. Partner hue from the complementary rule at the source colour's lightness. ΔH 179° > 140° — interpolating in oklch (shorter hue) keeps the midpoint saturated.

- CSS: `linear-gradient(135deg in oklch shorter hue, #00194a 0%, #291b00 100%)`
- Tailwind: `bg-linear-to-br/oklch from-[#00194a] to-[#291b00]`
- Contrast (worst point): white 16.03:1 AA · black 1.24:1 fail · banding high
- Maker: https://brandsweets.com/gradients/new/v1.00194a-291b00?a=135&in=oklch&hue=shorter

## Triadic

Primary #1a1a1a is achromatic — harmony rotates #00194a instead. Partner hue from the triadic rule at the source colour's lightness.

- CSS: `linear-gradient(135deg in oklab, #00194a 0%, #3f0009 100%)`
- Tailwind: `bg-linear-to-br/oklab from-[#00194a] to-[#3f0009]`
- Contrast (worst point): white 16.89:1 AA · black 1.21:1 fail · banding high
- Maker: https://brandsweets.com/gradients/new/v1.00194a-3f0009?a=135

## CSS custom properties (brand.css)

```css
:root {
  /* Brand gradient (derived) */
  /* worst-case contrast: white 9.29:1 AA, black 1.00:1 */
  --brand-gradient: linear-gradient(135deg in oklch shorter hue, #474747 0%, #1a1a1a 50%, #000000 100%);
  /* hero — worst-case contrast: white 9.29:1 AA, black 1.00:1; ink passes AA at the worst point */
  --brand-gradient-hero: linear-gradient(135deg in oklch shorter hue, #474747 0%, #1a1a1a 50%, #000000 100%);
  --brand-gradient-hero-ink: #ffffff;
  /* button — worst-case contrast: white 15.72:1 AA, black 1.11:1 */
  --brand-gradient-button: linear-gradient(180deg in oklch shorter hue, #232323 0%, #111111 100%);
  --brand-gradient-button-hover: linear-gradient(180deg in oklch shorter hue, #2b2b2b 0%, #181818 100%);
  --brand-gradient-button-active: linear-gradient(180deg in oklch shorter hue, #1c1c1c 0%, #0b0b0b 100%);
  --brand-gradient-button-ink: #ffffff;
}
```

## Gradient maker

Every maker URL is the gradient's state: `/gradients/new/v1.<hex>-<hex>[_pos]?a=135&in=oklch&hue=shorter&e=soft&g=8`. Hand one to a human, let them refine, and read the link they return.

## Connect an agent

Point any MCP client at the BrandSweets gradients endpoint for the same engine and corpus:

- Endpoint: https://mcp.brandsweets.com/gradients/mcp
- Tools: `make_gradient` (2–5 colours → CSS with the interpolation space, Tailwind v4, SVG, PNG URL, DTCG token + the contrast/banding/gamut report), `brand_gradients` (brand slug or palette → brand gradient, hero, button, variants).
- Resource: `gradients://corpus` — the whole bundled corpus as JSON.