# House style

The package ships these defaults; this file explains what you must still decide and what
you must not undo.

## Canvas

White background, natural `standalone` crop. No forced 16:9. No title by default. The top
holds at most two compact formula lines: the primary chain and, only if essential, one
companion definition.

Each stage is one horizontal algebraic row with a shared visual baseline. Use the fewest
stages that preserve the primary path. No unrelated branches, no dashboard panels.

## Type hierarchy

| element | size | macro / style |
|---|---|---|
| formula | `\large` | `\stformula` |
| stage label | `\small\bfseries`, muted | `st stage` |
| operator | `\Large` | `st op` |
| symbol | `\small` | `\stcaption` arg 2 |
| shape | `\scriptsize`, muted | `\stcaption` arg 3 |
| bottom prose | `\small` | `\stmeaningbox` |
| signature | `\scriptsize`, low contrast | `\stsignature` |

Never shrink below this to make something fit — see `layout.md`.

## Faces

Separate tiles with a small white gutter and 0.5–1 pt corner rounding (`\st@tile` does
this). Thin neutral brackets, `black!55`–`black!70` outer borders. No saturated
tensor-colored outlines, no continuous spreadsheet grid.

**Encode support before magnitude.** Every known zero stays white/unfilled; every shown
nonzero gets color. A diagonal matrix must read instantly as colored diagonal cells on a
white field. `pattern=diag/band/lower/upper/causal/data` fill exactly the structural
support.

## Color

Palette (already defined): `stTeal #4F8FA5`, `stOrange #EE995B`, `stCoral #C95B5B`,
`stViolet #8A74B5`, `stGray #85898F`. Muted, mid-chroma, paper-like. Do not add saturated
primaries.

- One semantic color per tensor role, held across every stage: `\stsetrole{q}{stTeal}`.
  Macros take a **role**, never a color.
- At most four active hue families per algebraic row, plus neutral gray. Vary lightness or
  reuse the related input/output family before spending a new hue.
- If sign matters: hue for sign, intensity for magnitude.
- Contrast comes from **lightness separation, not saturation**. Levels are `role!30`,
  `role!55`, `role!80` (`\stlevelpct`); white is reserved for zero/absence. Do not render
  a whole tensor in `role!5`–`role!15` pastel.
- Illustrative dense tensors use two or three **non-periodic** levels. `pattern=dense`
  composes coprime moduli to avoid this; a polynomial hash mod 3 makes rows 1, 2, 4, 5
  identical and the eye reads that stripe as structure in the data. No checkerboards, no
  regular stripes, no symmetric motifs unless they encode real structure.

## Bottom box

One full-width, low-contrast box, one reading column, three fixed-label rows:

- **Axes** — what each dimension means.
- **Objects** — semantic kind / domain / range (see `semantics.md`).
- **Mechanism** — at most two essential mappings, contractions, broadcasts or boundaries.

Narrow bold label rail, left-aligned ragged-right `\small` content, 8–10 pt inner padding,
0.4–0.6 em row gaps. Rail labels localize with the package option (`zh` default, `en`).
Keep each row compact: prefer symbol semantics over numeric configuration. When it is too
long, **remove content** — never add cards, columns or smaller type. Pass `{}` to omit a row.

## Signature

One centered line below the box, outside it, low-contrast gray, `\scriptsize` or smaller:
`\stsignature{<subject>}{<fit node>}` renders `<subject>@五道口纳什`. The subject must name
what this figure actually visualizes. Keep it on one line, with a small but visible gap.

## Never

Charts or metric insets not present in the primary formula. Decorative pills, banners,
shadows, repeated separators, explanatory cards.

## Reference image

`assets/kimi-matrix-style-reference.png` — inspect it with an image viewer before drawing
when entry-level matrix blocks are central or Kimi-like styling is requested. Use it only
to calibrate tile spacing, rounding, neutral brackets, restrained hue, lightness separation
and structural whitespace. Do not copy its content, and do not embed it in the output.

## Language

Chinese figures use concise Chinese labels with standard English terms where helpful
(`softmax`, `All-Reduce`, `gather` stay in English). Switch the whole figure at once —
`\usepackage[en]{supertensor}` plus English stage headings and box text — never mix.