# Tumblr gradient

Gradients derived from Tumblr'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/tumblr-com
- Brand colors: https://brandsweets.com/colors/brands/tumblr-com · Brand page: https://brandsweets.com/b/tumblr-com
- Palette: primary #304058, secondary #36465d, accents #ff4930
- Source: https://tumblr.com (extracted 2026-09-02)

## Brand gradient

ΔE_OK 0.022 < 0.15 between #304058 and #36465d — a 2-stop would read as a flat fill, so this is a tonal ramp of #304058.

- CSS: `linear-gradient(135deg in oklch shorter hue, #61728d 0%, #304058 50%, #061328 100%)`
- Tailwind: `bg-linear-to-br/oklch from-[#61728d] via-[#304058] to-[#061328]`
- Contrast (worst point): white 4.88:1 AA · black 1.13:1 fail · banding high
- Maker: https://brandsweets.com/gradients/new/v1.61728d-304058-061328?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 (4.90:1) without adjusting L.

- CSS: `linear-gradient(135deg in oklch shorter hue, #6c717b 0%, #3a4048 50%, #0f141b 100%)`
- Tailwind: `bg-linear-to-br/oklch from-[#6c717b] via-[#3a4048] to-[#0f141b]`
- Contrast (worst point): white 4.90:1 AA · black 1.14:1 fail · banding high · ink #ffffff
- Maker: https://brandsweets.com/gradients/new/v1.6c717b-3a4048-0f141b?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 7.82:1).

- CSS: `linear-gradient(180deg in oklch shorter hue, #3a4b63 0%, #26364d 100%)`
- Tailwind: `bg-linear-to-b/oklch from-[#3a4b63] to-[#26364d]`
- Contrast (worst point): white 8.87:1 AA · black 1.72:1 fail · banding high · ink #ffffff
- Maker: https://brandsweets.com/gradients/new/v1.3a4b63-26364d?a=180&in=oklch&hue=shorter
- Hover: `linear-gradient(180deg in oklch shorter hue, #42536c 0%, #2d3d55 100%)`
- Active: `linear-gradient(180deg in oklch shorter hue, #33435b 0%, #1f2e45 100%)`

## Tonal ramp

- CSS: `linear-gradient(135deg in oklch shorter hue, #61728d 0%, #304058 50%, #061328 100%)`
- Tailwind: `bg-linear-to-br/oklch from-[#61728d] via-[#304058] to-[#061328]`
- Contrast (worst point): white 4.88:1 AA · black 1.13:1 fail · banding high
- Maker: https://brandsweets.com/gradients/new/v1.61728d-304058-061328?a=135&in=oklch&hue=shorter

## Analogous

Partner hue from the analogous rule at the source colour's lightness.

- CSS: `linear-gradient(135deg in oklab, #304058 0%, #32424a 100%)`
- Tailwind: `bg-linear-to-br/oklab from-[#304058] to-[#32424a]`
- Contrast (worst point): white 10.38:1 AA · black 1.99:1 fail · banding high
- Maker: https://brandsweets.com/gradients/new/v1.304058-32424a?a=135

## Complementary

Partner hue from the complementary rule at the source colour's lightness. ΔH 180° > 140° — interpolating in oklch (shorter hue) keeps the midpoint saturated.

- CSS: `linear-gradient(135deg in oklch shorter hue, #304058 0%, #473e30 100%)`
- Tailwind: `bg-linear-to-br/oklch from-[#304058] to-[#473e30]`
- Contrast (worst point): white 10.23:1 AA · black 1.99:1 fail · banding high
- Maker: https://brandsweets.com/gradients/new/v1.304058-473e30?a=135&in=oklch&hue=shorter

## Triadic

Partner hue from the triadic rule at the source colour's lightness.

- CSS: `linear-gradient(135deg in oklab, #304058 0%, #573435 100%)`
- Tailwind: `bg-linear-to-br/oklab from-[#304058] to-[#573435]`
- Contrast (worst point): white 10.46:1 AA · black 1.94:1 fail · banding high
- Maker: https://brandsweets.com/gradients/new/v1.304058-573435?a=135

## CSS custom properties (brand.css)

```css
:root {
  /* Brand gradient (derived) */
  /* worst-case contrast: white 4.88:1 AA, black 1.13:1 */
  --brand-gradient: linear-gradient(135deg in oklch shorter hue, #61728d 0%, #304058 50%, #061328 100%);
  /* hero — worst-case contrast: white 4.90:1 AA, black 1.14:1; ink passes AA at the worst point */
  --brand-gradient-hero: linear-gradient(135deg in oklch shorter hue, #6c717b 0%, #3a4048 50%, #0f141b 100%);
  --brand-gradient-hero-ink: #ffffff;
  /* button — worst-case contrast: white 8.87:1 AA, black 1.72:1 */
  --brand-gradient-button: linear-gradient(180deg in oklch shorter hue, #3a4b63 0%, #26364d 100%);
  --brand-gradient-button-hover: linear-gradient(180deg in oklch shorter hue, #42536c 0%, #2d3d55 100%);
  --brand-gradient-button-active: linear-gradient(180deg in oklch shorter hue, #33435b 0%, #1f2e45 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.