# Colour

There is no brand colour. The printing is ink, measured for contrast in aluminium and graphite, and colour appears only where it means something.

Foundation · Free · https://tactileui.dev/docs/foundations/colour

## Colour is information

Every colour in the kit is a token, and the only hues among them are the lamps and the lit displays, each with one meaning. [Lamps and aurora](https://tactileui.dev/docs/foundations/lamps) says what each one means; [Finishes and themes](https://tactileui.dev/docs/foundations/finishes) lists the tokens that change with the finish.

## Contrast, measured

Output of `node kit/brain/tools/verify.mjs --contrast` on the current kit. Body text is `--tui-ink` or `--tui-ink-2`; `--tui-ink-3` is for scales and hints only.

| Ink | Ground | Aluminium | Graphite | Needs |
| - | - | - | - | - |
| ink | desk · face · well | 11.83 · 13.63 · 11.45 | 15.38 · 13.67 · 14.90 | 4.5 |
| ink-2 | desk · face · well | 5.88 · 6.77 · 5.69 | 7.97 · 7.08 · 7.72 | 4.5 |
| ink-3 | desk · face · well | 3.54 · 4.08 · 3.43 | 4.58 · 4.07 · 4.44 | 3 |

## What the kit refuses

An accent colour. A “brand” hue. Purple or blue-violet gradients. Terracotta or signal orange as a theme. Coloured text for emphasis: emphasis is weight, size or the contrast key. And colour as the only carrier of meaning: a lamp always sits next to words. The brain’s verify tool flags purple and orange literals by hue.

## The full law

This page is a summary in plain words. The brain holds the law itself, in `colour-and-lamps.md`, written for an agent to follow. It ships with the Kit.