# Una scheda in dieci tradizioni scolastiche

> Gli stessi sette blocchi :::exercise in dieci lingue, ogni edizione stampata con uno stile di esercizio che segue i libri di scuola del suo paese.

- Versione HTML: https://postext.dev/it/cookbook/school-traditions-worksheet
- Ricetta Nº 169 · Libri di testo · Livello 2 (Intermedio) · Output: Canvas, PDF
- Generi: Quaderni ed eserciziari, Libri di testo
- Richiede postext ≥ 1.59.0, postext-pdf ≥ 1.59.0 · provata con 1.59.0, postext-pdf 1.59.0 il 2026-10-24
- Pagine: [1](https://postext.dev/cookbook/school-traditions-worksheet/it/p01.webp?v=60ce0ae6), [2](https://postext.dev/cookbook/school-traditions-worksheet/it/p02.webp?v=60ce0ae6)
- PDF: https://postext.dev/cookbook/school-traditions-worksheet/it/school-traditions-worksheet.pdf?v=60ce0ae6
- Apri nella Sandbox: https://postext.dev/it/sandbox#recipe=school-traditions-worksheet&lang=it (.postext: https://postext.dev/cookbook/school-traditions-worksheet/it/school-traditions-worksheet.postext)
- Ultimo aggiornamento: 2026-10-24
- Altre lingue: [en](https://postext.dev/en/cookbook/school-traditions-worksheet.md), [es](https://postext.dev/es/cookbook/school-traditions-worksheet.md), [ca](https://postext.dev/ca/cookbook/school-traditions-worksheet.md), [de](https://postext.dev/de/cookbook/school-traditions-worksheet.md), [fr](https://postext.dev/fr/cookbook/school-traditions-worksheet.md), [pt](https://postext.dev/pt/cookbook/school-traditions-worksheet.md), [zh](https://postext.dev/zh/cookbook/school-traditions-worksheet.md), [ja](https://postext.dev/ja/cookbook/school-traditions-worksheet.md), [ar](https://postext.dev/ar/cookbook/school-traditions-worksheet.md)

## In breve

Una scheda di scienze e matematica di due pagine sul ciclo dell’acqua, fatta dieci volte. Le domande sono le stesse; i numeri, le caselle, le righe e la divisione hanno l’aspetto dei libri di scuola di ogni paese.

## Che cosa comporrai

La scheda 7 di un corso di scienze e matematica di classe quarta, *Il viaggio dell’acqua*, in dieci edizioni. Le domande sono le stesse in tutte le lingue: scegliere una risposta, segnare vero o falso, completare con le parole di un elenco, collegare le parole al loro significato, cerchiare una parola, dividere l’acqua di una cisterna, spiegare perché va risparmiata. Ogni edizione le stampa come fanno le sue scuole. Le schede spagnola e catalana mettono il numero in un cerchio, fanno segnare V o F e dividono con il divisore in una L a destra del dividendo. La francese usa quadrati, *cases à cocher*, spazi a puntini e carta Seyès per la risposta. La tedesca scrive *R* e *F*, *Lückentext* e `864 : 4 =` su una riga, con il punto per la moltiplicazione. La brasiliana chiede V o F tra parentesi. L’inglese divide sotto la parentesi ⟌. La cinese numera le sezioni 一、二、, mette （　） dopo ogni consegna con A. B. C. in fila, chiede √ o × e finisce con 看拼音，写词语 nei quadretti 田字格. La giapponese propone ア イ ウ e ○ ×, l’araba va da destra a sinistra con أ ب ج e صح o خطأ.

**Questa ricetta risponde a:**

- Come compongo la stessa scheda come i libri di scuola di ogni paese compongono i loro esercizi?
- Come compongo la divisione in colonna come la scrivono le scuole di ogni paese?
- Come compongo domande d'esame cinesi: una parentesi （　） dopo la domanda e le opzioni A. B. C. D. in fila?

## La risposta breve

```js
// script.js, righe 36–69
// The Markdown of every edition has the same seven exercises. What changes is this table:
// how the number prints, how options are labelled and answered, how true/false reads, where
// a blank is written, the paper of the open answer and the layout of long division.
const disc = { shape: 'disc' };
const square = { shape: 'square' };
const bare = { shape: 'none', suffix: '.' };
const TRADITIONS = {
  es: { number: disc, options: { marker: 'none' }, trueFalse: { look: 'boxes' },
    blank: { look: 'line' }, area: { kind: 'lines' }, arithmetic: { division: 'potence' } },
  fr: { number: square, options: { marker: 'box' }, trueFalse: { look: 'boxes' },
    blank: { look: 'dots' }, area: { kind: 'seyes', spacing: mm(8) },
    arithmetic: { division: 'potence' } },
  de: { number: square, options: { marker: 'box' }, trueFalse: { look: 'boxes' },
    blank: { look: 'line' }, area: { kind: 'lines' }, arithmetic: { division: 'inline' } },
  it: { number: { shape: 'rounded' }, options: { marker: 'box' }, trueFalse: { look: 'boxes' },
    blank: { look: 'dots' }, area: { kind: 'lines' }, arithmetic: { division: 'potence' } },
  pt: { number: bare, options: { marker: 'none' }, trueFalse: { look: 'bracket' },
    blank: { look: 'line' }, area: { kind: 'lines' }, arithmetic: { division: 'potence' } },
  en: { number: bare, options: { marker: 'none' }, trueFalse: { look: 'boxes' },
    blank: { look: 'line' }, area: { kind: 'lines' }, arithmetic: { division: 'bracket' } },
  // 一、二、 sections; （　） after the stem and A. B. C. in a row; √ × in a bracket; 田字格.
  zh: { number: { shape: 'none', format: 'simp-chinese-informal', suffix: '、' },
    options: { labels: 'alpha-upper', suffix: '.', layout: 'row', bracket: true },
    trueFalse: { look: 'bracket' }, blank: { look: 'line' },
    area: { kind: 'tianzige', spacing: mm(13), lines: 1 }, arithmetic: { division: 'bracket' } },
  // ア イ ウ in a row with （　）, ○ × in a bracket, the number in a square.
  ja: { number: square, options: { labels: 'katakana', suffix: '', layout: 'row', bracket: true },
    trueFalse: { look: 'bracket' }, blank: { look: 'line' }, area: { kind: 'lines' },
    arithmetic: { division: 'bracket' } },
  ar: { number: disc, options: { marker: 'none', prefix: '(', suffix: ')' },
    trueFalse: { look: 'boxes' },
    blank: { look: 'dots' }, area: { kind: 'lines' }, arithmetic: { division: 'bracket' } },
};
TRADITIONS.ca = TRADITIONS.es; // Catalan schools set exercises as Spanish ones do
```

## Ingredienti

**Insegna**

- [Stili di esercizio](https://postext.dev/it/docs/exercises.md#stili-degli-esercizi): exerciseStyles: come si stampa una famiglia di esercizi: il numero (cerchio, quadrato, etichetta), la consegna, le lettere delle opzioni, gli spazi vuoti, le caselle V/F, i punti da collegare, la banca di parole, gli spazi di scrittura, le griglie, le icone di attività e la difficoltà.
- [Operazioni in colonna](https://postext.dev/it/docs/exercises.md#operazioni-in-colonna): Operazioni in colonna (+ − ×) con una casella per ogni cifra, e la divisione in colonna come la scrivono le scuole di ogni lingua: la parentesi ⟌ inglese, lo schema italiano a L o il 864 : 4 = tedesco in riga.
- [Scelta e vero o falso](https://postext.dev/it/docs/exercises.md#scelta-multipla-e-vero-o-falso): Scelta multipla da un elenco di attività (- [x] giusta, - [ ] sbagliata), con a) b) c), A. B. C., ア イ ウ o أ ب ج e una casella, un cerchio o una parentesi per rispondere; affermazioni vero o falso con le lettere della lingua.

**Usa anche**

- [Esercizi](https://postext.dev/it/docs/exercises.md#esercizi)
- [Spazi vuoti e banche di parole](https://postext.dev/it/docs/exercises.md#completamento-e-riquadro-di-parole)
- [Collegare e classificare](https://postext.dev/it/docs/exercises.md#collegamento-e-classificazione)
- [Domande aperte e spazi di scrittura](https://postext.dev/it/docs/exercises.md#domande-aperte-e-spazi-per-scrivere)
- [Aperture progettate](https://postext.dev/it/docs/configuration-headings.md#estensione-e-grafica-avanzata)
- [Attributi dei titoli](https://postext.dev/it/docs/document-format.md#attributi-dei-titoli)
- [Tavolozza di colori semantica](https://postext.dev/it/docs/configuration-fonts-colors-viewers.md#tavolozza-dei-colori)
- [Font cinesi, giapponesi e coreani](https://postext.dev/it/docs/configuration-pdf-output.md#font-cinesi-giapponesi-e-coreani)
- [Font arabi](https://postext.dev/it/docs/arabic-layout.md#font)
- [Libri rilegati a destra](https://postext.dev/it/docs/configuration-page-layout.md#rilegatura)
- [Testo da destra a sinistra](https://postext.dev/it/docs/arabic-layout.md#direzione-e-algoritmo-bidirezionale)
- [Sillabazione e lingua del documento](https://postext.dev/it/docs/justification.md#lingue-supportate)
- [Pagine su un canvas](https://postext.dev/it/docs/configuration-programmatic-usage.md#rasterizzare-una-pagina)
- [Esportazione in PDF](https://postext.dev/it/docs/configuration-pdf-output.md#generare-pdf)
- [Soluzioni](https://postext.dev/it/docs/exercises.md#soluzioni)
- [Stili di paragrafo](https://postext.dev/it/docs/configuration-styles.md#stili-di-paragrafo)
- [Font incorporati nel PDF](https://postext.dev/it/docs/configuration-pdf-output.md#perché-un-provider-di-font)

**La configurazione in breve**

- [`bodyText`](https://postext.dev/it/docs/configuration-text.md#testo-corrente), [`colorPalette`](https://postext.dev/it/docs/configuration-fonts-colors-viewers.md#tavolozza-dei-colori), `exerciseStyles`, [`footer`](https://postext.dev/it/docs/configuration-headers-footers.md#intestazioni-e-piè-di-pagina), [`header`](https://postext.dev/it/docs/configuration-headers-footers.md#intestazioni-e-piè-di-pagina), [`headings`](https://postext.dev/it/docs/configuration-headings.md#titoli), [`layout`](https://postext.dev/it/docs/configuration-page-layout.md#impaginazione), [`locale`](https://postext.dev/it/docs/configuration-language.md#sillabazione), [`orderedLists`](https://postext.dev/it/docs/configuration-lists-math.md#elenchi-numerati), [`page`](https://postext.dev/it/docs/configuration-page-layout.md#pagina), [`paragraphStyles`](https://postext.dev/it/docs/configuration-styles.md#stili-di-paragrafo)

**API**

- [`buildDocument`](https://postext.dev/it/docs/configuration-programmatic-usage.md#costruire-un-documento), [`decompressWoff2`](https://postext.dev/it/docs/configuration-pdf-output.md#provider-di-font-per-il-browser-fontsource--woff2), [`renderPageToCanvas`](https://postext.dev/it/docs/configuration-programmatic-usage.md#rasterizzare-una-pagina), [`renderToPdf`](https://postext.dev/it/docs/configuration-pdf-output.md#generare-pdf), [`withLoadedFonts`](https://postext.dev/it/docs/configuration-programmatic-usage.md#caricare-i-font-prima-dellimpaginazione)

**Caratteri**

- Nunito (OFL-1.1), Baloo 2 (OFL-1.1), Noto Serif SC (OFL-1.1), Noto Sans SC (OFL-1.1), Klee One (OFL-1.1), Noto Sans JP (OFL-1.1), Noto Naskh Arabic (OFL-1.1), Baloo Bhaijaan 2 (OFL-1.1)

## Preparazione

### 1 · Metti ogni tradizione in una tabella

```js
// script.js, righe 36–69
// The Markdown of every edition has the same seven exercises. What changes is this table:
// how the number prints, how options are labelled and answered, how true/false reads, where
// a blank is written, the paper of the open answer and the layout of long division.
const disc = { shape: 'disc' };
const square = { shape: 'square' };
const bare = { shape: 'none', suffix: '.' };
const TRADITIONS = {
  es: { number: disc, options: { marker: 'none' }, trueFalse: { look: 'boxes' },
    blank: { look: 'line' }, area: { kind: 'lines' }, arithmetic: { division: 'potence' } },
  fr: { number: square, options: { marker: 'box' }, trueFalse: { look: 'boxes' },
    blank: { look: 'dots' }, area: { kind: 'seyes', spacing: mm(8) },
    arithmetic: { division: 'potence' } },
  de: { number: square, options: { marker: 'box' }, trueFalse: { look: 'boxes' },
    blank: { look: 'line' }, area: { kind: 'lines' }, arithmetic: { division: 'inline' } },
  it: { number: { shape: 'rounded' }, options: { marker: 'box' }, trueFalse: { look: 'boxes' },
    blank: { look: 'dots' }, area: { kind: 'lines' }, arithmetic: { division: 'potence' } },
  pt: { number: bare, options: { marker: 'none' }, trueFalse: { look: 'bracket' },
    blank: { look: 'line' }, area: { kind: 'lines' }, arithmetic: { division: 'potence' } },
  en: { number: bare, options: { marker: 'none' }, trueFalse: { look: 'boxes' },
    blank: { look: 'line' }, area: { kind: 'lines' }, arithmetic: { division: 'bracket' } },
  // 一、二、 sections; （　） after the stem and A. B. C. in a row; √ × in a bracket; 田字格.
  zh: { number: { shape: 'none', format: 'simp-chinese-informal', suffix: '、' },
    options: { labels: 'alpha-upper', suffix: '.', layout: 'row', bracket: true },
    trueFalse: { look: 'bracket' }, blank: { look: 'line' },
    area: { kind: 'tianzige', spacing: mm(13), lines: 1 }, arithmetic: { division: 'bracket' } },
  // ア イ ウ in a row with （　）, ○ × in a bracket, the number in a square.
  ja: { number: square, options: { labels: 'katakana', suffix: '', layout: 'row', bracket: true },
    trueFalse: { look: 'bracket' }, blank: { look: 'line' }, area: { kind: 'lines' },
    arithmetic: { division: 'bracket' } },
  ar: { number: disc, options: { marker: 'none', prefix: '(', suffix: ')' },
    trueFalse: { look: 'boxes' },
    blank: { look: 'dots' }, area: { kind: 'lines' }, arithmetic: { division: 'bracket' } },
};
TRADITIONS.ca = TRADITIONS.es; // Catalan schools set exercises as Spanish ones do
```

Tutte le edizioni hanno lo stesso Markdown: sette blocchi `:::exercise` con le risposte nel testo (`- [x]`, `[[vapore]]`, `- Evaporazione -> L'acqua diventa vapore`, `- 864 : 4`). Ciò che cambia da un paese all’altro è la forma, quindi sta in questa tabella e in nessun altro posto: la figura e le cifre del numero, le lettere delle opzioni e se l’alunno barra una casella o cerchia una lettera, l’aspetto del vero o falso, quello degli spazi da completare, l’area di scrittura e la disposizione della divisione in colonna. Il catalano prende la riga dello spagnolo così com’è.

### 2 · Stendi la tradizione sopra lo stile della casa

```js
// script.js, righe 73–87
const T = TRADITIONS[LANG];
const ficha = {
  id: 'ficha', ...T,
  number: { background: col('accent'), color: T.number.shape === 'none' ? col('accent')
    : col('paper'), fontFamily: LABEL, fontWeight: 700, ...T.number },
  // Chinese and Japanese sheets set the instructions in the gothic (黑体, ゴシック).
  instruction: { bold: true, color: col('ink'), ...(LANG === 'zh' || LANG === 'ja'
    ? { fontFamily: LABEL } : {}) },
  blank: { color: col('ink'), weight: pt(0.7), ...T.blank },
  match: { look: 'dots', gap: em(5), color: col('accent') },
  bank: { order: 'alpha' },
  area: { color: col('rule'), spacing: mm(9), weight: pt(0.6), ...T.area },
  grid: { cell: mm(8.5), fontFamily: TEXT, rule: col('rule'), color: col('ink') },
  marginTop: mm(7), marginBottom: mm(1), itemSpacing: em(0.4),
};
```

Un solo stile di esercizio, `ficha`, porta ciò che le dieci schede hanno in comune (il blu dei numeri, i filetti grigi, lo spazio tra gli esercizi), e la riga dell’edizione ci si stende sopra. Ciò che la riga non dice viene dalla lingua: T F, V F, R F, √ ×, ○ × e صح خطأ sono parole del motore stesso, come a) b) c), A. B. C., ア イ ウ e أ ب ج, perciò nessuna edizione le scrive.

### 3 · Dai a ogni scrittura i suoi font

```js
// script.js, righe 27–32
const FACES = {
  zh: { text: 'Noto Serif SC', label: 'Noto Sans SC' },
  ja: { text: 'Klee One', label: 'Noto Sans JP' },
  ar: { text: 'Noto Naskh Arabic', label: 'Baloo Bhaijaan 2' },
}[LANG] ?? { text: 'Nunito', label: 'Baloo 2' };
const [TEXT, LABEL] = [FACES.text, FACES.label];
```

Le edizioni in alfabeto latino condividono Nunito e Baloo 2. La scheda cinese compone il testo in Song e le consegne in Hei; quella giapponese il testo in Klee One, un carattere da libro di testo, e le consegne in un bastoni giapponese (gothic); quella araba usa Noto Naskh Arabic. Il peso più nero di Klee One è il 600, quindi l’edizione giapponese mette il suo grassetto a 600 (`boldFontWeight`): un 700 lo disegnerebbe il browser e la cattura fallirebbe.

### 4 · Apri la scheda con le righe per il nome

```js
// script.js, righe 91–110
const at = (to, edge, x = 0, y = 0, size) => ({ anchor: { to, edge },
  offset: { x: mm(x), y: mm(y) }, ...(size && { size }) });
const field = (id, attr, x, width) => [
  { kind: 'text', id, content: `{attr.${attr}}`, fontFamily: LABEL, fontSize: pt(10),
    fontWeight: 700, color: col('muted'), align: 'left', placement: at('container', 'top-left',
      x, 28) },
  { kind: 'rule', id: `${id}-line`, direction: 'horizontal', thickness: pt(0.75),
    color: col('rule'), placement: at('container', 'top-left', x + 16, 33, { width: mm(width) }) },
];
const head = { enabled: true, minHeight: mm(38), slot: { elements: [
  { kind: 'box', id: 'band', style: { backgroundColor: col('accent'), borderRadius: mm(3) },
    placement: at('container', 'top-left', 0, 0, { width: 'fill', height: mm(21) }) },
  { kind: 'text', id: 'kicker', content: '{title} · {subtitle}', fontFamily: LABEL,
    fontSize: pt(8.5), fontWeight: 700, color: col('tint'), align: 'left',
    placement: at('container', 'top-left', 6, 3.5) },
  { kind: 'text', id: 'title', content: '{titleText}', fontFamily: LABEL, fontSize: pt(22),
    fontWeight: 700, color: col('paper'), align: 'left', lineHeight: 1.1,
    placement: at('container', 'top-left', 6, 9.5) },
  ...field('name', 'nombre', 0, 96), ...field('date', 'fecha', 120, 40),
] } };
```

Il titolo di livello 1 disegna la fascia, il corso preso dal frontmatter e il titolo, più due campi con una riga le cui parole vengono dagli attributi del titolo (`nombre="Nome" fecha="Data"`). Così la scheda tedesca dice *Datum* e quella giapponese 名前 senza una stringa nel codice.

## La ricetta completa

Un unico file, composto a partire dalla cartella della ricetta con il testo di esempio e il kit comune del Ricettario già inclusi; costruisce la propria pagina. Per eseguirlo, mettilo in uno `<script type="module">` di una pagina vuota, oppure incollalo nel pannello JS di un nuovo pen di CodePen (come modulo). Importa postext da esm.sh: non c’è niente da installare né da compilare.

- Cartella della ricetta: https://github.com/drnachio/postext/tree/main/cookbook/school-traditions-worksheet

### script.js

```js
// ═══ Postext Cookbook · Nº 169 · One worksheet in ten school traditions ═════════
// https://postext.dev/en/cookbook/school-traditions-worksheet
// Code: MIT · Text: original (CC BY 4.0) · Pictures: none
// Fonts: Nunito, Baloo 2, Klee One, Noto Naskh Arabic and others (SIL OFL) · Needs postext ≥ 1.59.0
import {
  buildDocument, withLoadedFonts, renderPageToCanvas,
} from 'https://esm.sh/postext';
import { renderToPdf, decompressWoff2 } from 'https://esm.sh/postext-pdf';

const LANG = 'it'; // @lang: the language of the worksheet (en es ca fr de it pt zh ja ar)
const RECIPE = 'school-traditions-worksheet';

// ─── 1 · Design ─────────────────────────────────────────────────────────────
// #region palette: a blue-black ink, one blue accent, a pale tint, grey rules
const palette = {
  ink: '#1d2633', accent: '#2a5d9f', tint: '#e8f0fa', rule: '#a9b6c6', muted: '#5d6878',
  paper: '#ffffff',
};
const col = (id) => ({ hex: palette[id], model: 'hex', paletteId: id });
const colorPalette = [
  ...Object.entries(palette).map(([id, hex]) => ({ id, name: id, value: { hex, model: 'hex' } })),
  { id: 'main-color', name: 'accent (defaults)', value: { hex: palette.accent, model: 'hex' } },
];
// #endregion

// #region faces: Latin editions share two faces; Chinese, Japanese and Arabic their own
const FACES = {
  zh: { text: 'Noto Serif SC', label: 'Noto Sans SC' },
  ja: { text: 'Klee One', label: 'Noto Sans JP' },
  ar: { text: 'Noto Naskh Arabic', label: 'Baloo Bhaijaan 2' },
}[LANG] ?? { text: 'Nunito', label: 'Baloo 2' };
const [TEXT, LABEL] = [FACES.text, FACES.label];
// #endregion

// #region answer: the form of the exercises, as each country's school books set them
// The Markdown of every edition has the same seven exercises. What changes is this table:
// how the number prints, how options are labelled and answered, how true/false reads, where
// a blank is written, the paper of the open answer and the layout of long division.
const disc = { shape: 'disc' };
const square = { shape: 'square' };
const bare = { shape: 'none', suffix: '.' };
const TRADITIONS = {
  es: { number: disc, options: { marker: 'none' }, trueFalse: { look: 'boxes' },
    blank: { look: 'line' }, area: { kind: 'lines' }, arithmetic: { division: 'potence' } },
  fr: { number: square, options: { marker: 'box' }, trueFalse: { look: 'boxes' },
    blank: { look: 'dots' }, area: { kind: 'seyes', spacing: mm(8) },
    arithmetic: { division: 'potence' } },
  de: { number: square, options: { marker: 'box' }, trueFalse: { look: 'boxes' },
    blank: { look: 'line' }, area: { kind: 'lines' }, arithmetic: { division: 'inline' } },
  it: { number: { shape: 'rounded' }, options: { marker: 'box' }, trueFalse: { look: 'boxes' },
    blank: { look: 'dots' }, area: { kind: 'lines' }, arithmetic: { division: 'potence' } },
  pt: { number: bare, options: { marker: 'none' }, trueFalse: { look: 'bracket' },
    blank: { look: 'line' }, area: { kind: 'lines' }, arithmetic: { division: 'potence' } },
  en: { number: bare, options: { marker: 'none' }, trueFalse: { look: 'boxes' },
    blank: { look: 'line' }, area: { kind: 'lines' }, arithmetic: { division: 'bracket' } },
  // 一、二、 sections; （　） after the stem and A. B. C. in a row; √ × in a bracket; 田字格.
  zh: { number: { shape: 'none', format: 'simp-chinese-informal', suffix: '、' },
    options: { labels: 'alpha-upper', suffix: '.', layout: 'row', bracket: true },
    trueFalse: { look: 'bracket' }, blank: { look: 'line' },
    area: { kind: 'tianzige', spacing: mm(13), lines: 1 }, arithmetic: { division: 'bracket' } },
  // ア イ ウ in a row with （　）, ○ × in a bracket, the number in a square.
  ja: { number: square, options: { labels: 'katakana', suffix: '', layout: 'row', bracket: true },
    trueFalse: { look: 'bracket' }, blank: { look: 'line' }, area: { kind: 'lines' },
    arithmetic: { division: 'bracket' } },
  ar: { number: disc, options: { marker: 'none', prefix: '(', suffix: ')' },
    trueFalse: { look: 'boxes' },
    blank: { look: 'dots' }, area: { kind: 'lines' }, arithmetic: { division: 'bracket' } },
};
TRADITIONS.ca = TRADITIONS.es; // Catalan schools set exercises as Spanish ones do
// #endregion

// #region style: the one exercise style, the edition's tradition over the house look
const T = TRADITIONS[LANG];
const ficha = {
  id: 'ficha', ...T,
  number: { background: col('accent'), color: T.number.shape === 'none' ? col('accent')
    : col('paper'), fontFamily: LABEL, fontWeight: 700, ...T.number },
  // Chinese and Japanese sheets set the instructions in the gothic (黑体, ゴシック).
  instruction: { bold: true, color: col('ink'), ...(LANG === 'zh' || LANG === 'ja'
    ? { fontFamily: LABEL } : {}) },
  blank: { color: col('ink'), weight: pt(0.7), ...T.blank },
  match: { look: 'dots', gap: em(5), color: col('accent') },
  bank: { order: 'alpha' },
  area: { color: col('rule'), spacing: mm(9), weight: pt(0.6), ...T.area },
  grid: { cell: mm(8.5), fontFamily: TEXT, rule: col('rule'), color: col('ink') },
  marginTop: mm(7), marginBottom: mm(1), itemSpacing: em(0.4),
};
// #endregion

// #region head: the worksheet's head, its title on a tinted band and the lines for a name
const at = (to, edge, x = 0, y = 0, size) => ({ anchor: { to, edge },
  offset: { x: mm(x), y: mm(y) }, ...(size && { size }) });
const field = (id, attr, x, width) => [
  { kind: 'text', id, content: `{attr.${attr}}`, fontFamily: LABEL, fontSize: pt(10),
    fontWeight: 700, color: col('muted'), align: 'left', placement: at('container', 'top-left',
      x, 28) },
  { kind: 'rule', id: `${id}-line`, direction: 'horizontal', thickness: pt(0.75),
    color: col('rule'), placement: at('container', 'top-left', x + 16, 33, { width: mm(width) }) },
];
const head = { enabled: true, minHeight: mm(38), slot: { elements: [
  { kind: 'box', id: 'band', style: { backgroundColor: col('accent'), borderRadius: mm(3) },
    placement: at('container', 'top-left', 0, 0, { width: 'fill', height: mm(21) }) },
  { kind: 'text', id: 'kicker', content: '{title} · {subtitle}', fontFamily: LABEL,
    fontSize: pt(8.5), fontWeight: 700, color: col('tint'), align: 'left',
    placement: at('container', 'top-left', 6, 3.5) },
  { kind: 'text', id: 'title', content: '{titleText}', fontFamily: LABEL, fontSize: pt(22),
    fontWeight: 700, color: col('paper'), align: 'left', lineHeight: 1.1,
    placement: at('container', 'top-left', 6, 9.5) },
  ...field('name', 'nombre', 0, 96), ...field('date', 'fecha', 120, 40),
] } };
// #endregion

const config = {
  locale: t({ en: 'en-gb', es: 'es', ca: 'ca', fr: 'fr', de: 'de', it: 'it', pt: 'pt-BR',
    zh: 'zh-Hans', ja: 'ja', ar: 'ar' }),
  colorPalette,
  page: { sizePreset: 'custom', width: mm(210), height: mm(297), dpi: 150,
    margins: { top: mm(18), bottom: mm(20), left: mm(18), right: mm(18), mirror: true } },
  layout: { layoutType: 'single' },
  bodyText: {
    fontFamily: TEXT, fontSize: pt(LANG === 'ar' ? 13.5 : 12), lineHeight: pt(LANG === 'ar'
      ? 22 : 18), color: col('ink'), boldColor: col('ink'), italicColor: col('ink'),
    referenceColor: col('ink'), textAlign: 'left', firstLineIndent: pt(0),
    boldFontWeight: LANG === 'ja' ? 600 : 700, // Klee One's heaviest cut is 600
    paragraphSpacing: false, hyphenation: { enabled: false }, optimalLineBreaking: true,
    avoidWidows: true, avoidOrphans: true, avoidRunts: true,
  },
  headings: { fontFamily: LABEL, color: col('ink'), fontWeight: 700, levels: [
    { level: 1, fontSize: pt(20), breakBefore: { parity: 'any' }, marginTop: pt(0),
      marginBottom: mm(1), advancedDesign: head },
  ] },
  exerciseStyles: [ficha],
  orderedLists: { fontFamily: LABEL, color: col('accent'), fontWeight: 700, marginTop: pt(0),
    marginBottom: pt(0) },
  paragraphStyles: [{ id: 'colophon', fontFamily: TEXT, fontSize: pt(7.5), lineHeight: pt(10),
    color: col('muted'), firstLineIndent: pt(0), marginTop: mm(6) }],
  header: { elements: [] },
  footer: { elements: [{ kind: 'text', id: 'folio', content: '{pageNumber}', fontFamily: LABEL,
    fontSize: pt(9), fontWeight: 700, color: col('accent'), align: 'center',
    placement: at('page', 'bottom', 0, -11) }] },
};

// ─── 2 · Content ────────────────────────────────────────────────────────────
const markdown = String.raw`---
title: "Scienze e matematica · Classe quarta"
subtitle: "Scheda 7"
---

# Il viaggio dell'acqua {nombre="Nome" fecha="Data"}

L'acqua sulla Terra è sempre in movimento. Il sole scalda il mare, l'acqua sale nel cielo e torna giù come pioggia o neve. Questo viaggio si chiama ciclo dell'acqua.

:::exercise
Segna con una crocetta la risposta giusta.

1. L'acqua che cade dalle nuvole si chiama
   - [ ] vapore
   - [x] pioggia
   - [ ] nebbia
2. Quando il sole scalda il mare, l'acqua
   - [x] evapora
   - [ ] gela
   - [ ] va a fondo
:::

:::exercise{type="truefalse"}
Vero o falso? Segna con una crocetta.

- [x] Le nuvole sono fatte di minuscole goccioline d'acqua.
- [ ] Il ghiaccio si scioglie quando fa più freddo.
- [x] I fiumi riportano l'acqua al mare.
- [ ] La pioggia è salata perché viene dal mare.
:::

:::exercise{bank}
Completa con le parole del riquadro.

::bank[ghiaccio | vento]

Il sole scalda il [[mare]]. L'acqua diventa [[vapore]] e sale. In alto si raffredda e forma le [[nuvole]]. Poi ricade come [[pioggia]] o neve.
:::

:::exercise
Collega ogni parola al suo significato.

- Evaporazione -> L'acqua diventa vapore
- Condensazione -> Il vapore diventa gocce
- Precipitazione -> L'acqua cade dalle nuvole
- Infiltrazione -> L'acqua entra nel terreno
:::

:::exercise
Cerchia la parola giusta.

1. La neve è acqua allo stato [[liquido | (solido)]].
2. Le pozzanghere si asciugano prima nei giorni [[(di sole) | nuvolosi]].
3. Quasi tutta l'acqua della Terra è [[dolce | (salata)]].
:::

:::exercise{type="arithmetic"}
La cisterna della scuola contiene 864 litri d'acqua. Quattro classi se li dividono in parti uguali. Quanti litri spettano a ogni classe? Esegui la divisione in colonna e fai la prova.

- 864 : 4
- 216 × 4
:::

:::exercise{type="open" lines="5"}
Perché dobbiamo risparmiare l'acqua? Scrivi due motivi.

:::solution
L'acqua dolce è poca, e per pulirla e portarla nelle nostre case serve energia.
:::
:::

:::paragraphs{style="colophon"}
Composto in Nunito e Baloo 2 (SIL OFL) · Testo originale (CC BY 4.0)
:::
`; // content.<lang>.md, inlined by the Cookbook

// ─── 3 · Fonts ──────────────────────────────────────────────────────────────
const FONTS = {
  Nunito: ['400', '700'], 'Baloo 2': ['700'], // the Latin editions
  'Noto Serif SC': ['400', '700'], 'Noto Sans SC': ['700'], // 宋 for the text, 黑 for heads
  'Klee One': ['400', '600'], 'Noto Sans JP': ['600', '700'], // 教科書体 and a gothic
  'Noto Naskh Arabic': ['400', '700'], 'Baloo Bhaijaan 2': ['700'],
};

// ─── 4 · Build & show ───────────────────────────────────────────────────────
// The edition loads its own faces only.
for (const family of Object.keys(FONTS)) if (![TEXT, LABEL].includes(family)) delete FONTS[family];
await loadFonts(FONTS, markdown);
await loadCjkFonts(FONTS, markdown);
await loadArabicFonts(FONTS, markdown);
const doc = await withLoadedFonts(() => buildDocument({ markdown }, config),
  { ...kitFonts(FONTS), text: markdown });
showBook(doc, { title: t({ en: 'Worksheet', es: 'Ficha', ca: 'Fitxa', fr: 'Fiche',
  de: 'Arbeitsblatt', it: 'Scheda', pt: 'Ficha', zh: '练习单', ja: 'プリント', ar: 'ورقة عمل' }) });
offerPdf(() => renderToPdf(doc, { fontProvider: { zh: cjkPdfProvider, ja: cjkPdfProvider,
  ar: arabicPdfProvider }[LANG] ?? fontsourceProvider }), `${RECIPE}-${LANG}.pdf`);

// ─── Kit ── helpers shared by every Cookbook recipe · postext.dev/cookbook ─────

// ─── Kit · core v1 ── the same in every recipe · postext.dev/cookbook
function mm(value) { return { value, unit: 'mm' }; }
function pt(value) { return { value, unit: 'pt' }; }
function em(value) { return { value, unit: 'em' }; }
/** The sample language's string: t({ en: 'Figure', es: 'Figura' }). */
function t(strings) { return strings[LANG] ?? Object.values(strings)[0]; }
/** A file in this recipe's assets folder, served from the Postext repo by jsDelivr. */
function asset(file) { return `https://cdn.jsdelivr.net/gh/drnachio/postext@main/cookbook/${RECIPE}/assets/${file}`; }

// ─── Kit · fonts v3 ── the same in every recipe · postext.dev/cookbook
// Postext loads the faces a config asks for before layout and asks the kit
// for Fontsource's files, the ones the PDF embeds too.

/** buildDocumentWithFonts' options: the resolver, and FONTS' faces loaded
 *  with the config's. FONTS = { 'Family Name': ['400', '400i', '700'] }. */
function kitFonts(FONTS = {}) {
  const faces = Object.entries(FONTS).flatMap(([family, specs]) => specs.map((spec) =>
    ({ family, weight: parseInt(spec, 10), style: spec.endsWith('i') ? 'italic' : 'normal' })));
  return { resolve: fontsourceResolver, faces };
}

/** A face's files with their ranges: latin, then latin-ext and greek when
 *  `text` needs them (kitSubsetsFor). Null for a face Fontsource lacks. */
async function fontsourceResolver(family, weight, style, { text = '' } = {}) {
  const id = fontsourceId(family);
  const meta = await fontsourceMeta(family);
  if (meta && !(await fontsourceWeights(family, style)).includes(weight)) return null;
  kitStatus('Loading fonts…');
  const at = await fontsourceAt(id);
  return ['latin', ...kitSubsetsFor(text, meta)].map((subset) => ({
    source: `${at}files/${id}-${subset}-${weight}-${style}.woff2`,
    unicodeRange: kitRanges()[subset],
  }));
}

/** Each file's unicode-range (a function: the kit runs after the pen's code). */
function kitRanges() {
  return {
    latin: 'U+0000-00FF,U+0131,U+0152-0153,U+02BB-02BC,U+02C6,U+02DA,U+02DC,U+0304,U+0308,U+0329,'
      + 'U+2000-206F,U+20AC,U+2122,U+2191,U+2193,U+2212,U+2215,U+FEFF,U+FFFD',
    'latin-ext': 'U+0100-02BA,U+02BD-02C5,U+02C7-02CC,U+02CE-02D7,U+02DD-02FF,U+0304,U+0308,U+0329,'
      + 'U+1D00-1DBF,U+1E00-1E9F,U+1EF2-1EFF,U+2020,U+20A0-20AB,U+20AD-20C0,U+2113,U+2C60-2C7F,U+A720-A7FF',
    greek: 'U+0370-03FF',
  };
}

/** For the cjk, arabic and comics blocks: loads `faces` (as FONTS) for the
 *  sample `text`; `optional` skips a face Fontsource lacks. Files are added in
 *  the order asked, the last winning a shared character. Resolves to the count. */
async function loadFonts(faces, text = '', { optional = false } = {}) {
  kitStatus('Loading fonts…');
  const ranges = kitRanges();
  const jobs = [];
  for (const [family, specs] of Object.entries(faces)) {
    const id = fontsourceId(family);
    const todo = [...new Set(specs)].map((spec) => [parseInt(spec, 10), spec.endsWith('i') ? 'italic' : 'normal'])
      .filter(([weight, style]) => !hasFace(family, weight, style)); // before any await
    const at = fontsourceAt(id);
    const meta = optional || /[^\0-ÿ]/u.test(text) ? await fontsourceMeta(family) : null;
    const subsets = ['latin', ...kitSubsetsFor(text, meta)];
    for (const [weight, style] of todo) {
      if (optional && !(meta && (await fontsourceWeights(family, style)).includes(weight))) continue;
      for (const subset of subsets) {
        const url = `${await at}files/${id}-${subset}-${weight}-${style}.woff2`;
        const face = new FontFace(family, `url(${url}) format('woff2')`,
          { weight: String(weight), style, unicodeRange: ranges[subset] });
        jobs.push(face.load().catch(() => {
          if (subset === 'latin' && !optional) throw new Error(`Fontsource has no ${family} ${weight} ${style}`);
        }));
      }
    }
  }
  const ready = await Promise.all(jobs).catch((error) => { kitFail(error); throw error; });
  return ready.filter((face) => face && document.fonts.add(face)).length;
}

/** A loaded FontFace covers this face (fonts.check() says yes to any family). */
function hasFace(family, weight, style) {
  for (const face of document.fonts) {
    if (face.status !== 'loaded' || face.style !== style) continue;
    if (face.family.replace(/^["']|["']$/g, '') !== family) continue;
    const [low, high = low] = face.weight.split(' ').map(Number);
    if (weight >= low && weight <= high) return true;
  }
  return false;
}

/** The files beyond latin `text` needs that `meta`'s family ships. */
function kitSubsetsFor(text, meta) {
  return [[/[Ā-˿ᴀ-ᶿḀ-ỿ†ℓⱠ-Ɀ꜠-ꟿ]/u, 'latin-ext'], [/[Ͱ-Ͽ]/u, 'greek']]
    .filter(([re, x]) => re.test(text) && meta?.subsets?.includes(x)).map(([, x]) => x);
}

/** Fontsource's id for a family: 'Source Serif 4' → 'source-serif-4'. */
function fontsourceId(family) { return family.toLowerCase().replace(/\s+/g, '-'); }

/** A package's folder at the one version @5 names now (#766). */
function fontsourceAt(id, u = `https://cdn.jsdelivr.net/npm/@fontsource/${id}@`) {
  return (fontsourceAt.c ??= {})[id] ??= fetch(u + '5/package.json').then((r) => r.json())
    .then((p) => p.version || 5, () => 5).then((v) => `${u}${v}/`);
}

/** The family's Fontsource metadata (weights, styles, subsets), or null. */
function fontsourceMeta(family, id = fontsourceId(family)) {
  return (fontsourceMeta.c ??= {})[id] ??= fetch(`https://api.fontsource.org/v1/fonts/${id}`)
    .then((res) => (res.ok ? res.json() : null), () => null);
}

/** The weights the package ships in `style`: the API pairs none (no Libre
 *  Caslon 700 italic file), so italics are read from latin-italic.css. */
function fontsourceWeights(family, style, id = fontsourceId(family)) {
  return (fontsourceWeights.c ??= {})[id + style] ??= fontsourceMeta(family).then(async (m) => {
    if (!m?.styles.includes(style)) return m ? [] : [400, 700];
    const css = style === 'italic' ? await fetch(`${await fontsourceAt(id)}latin-italic.css`).then((r) => (r.ok ? r.text() : ''), () => '') : '';
    const w = [...css.matchAll(/weight: (\d+)/g)].map((x) => +x[1]);
    return w.length ? w : m.weights;
  });
}

// ─── Kit · viewer v2 ── the same in every recipe · postext.dev/cookbook
/** The pages as spreads on a dark desk, page 1 alone, then verso | recto,
 *  each painted when it scrolls near. Other options go to renderPageToCanvas. */
function showPages(docs, { title, width = 460, ...render } = {}) {
  const root = viewer(title);
  const pages = [docs].flat().flatMap((doc) =>
    doc.pages.map((page) => ({ doc, page, n: (doc.pageIndexOffset ?? 0) + page.index })));
  const spreads = [];
  let verso = null;
  for (const p of pages) {
    if (p.n % 2 === 1) { if (verso) spreads.push([verso, null]); verso = p; }
    else { spreads.push([verso, p]); verso = null; }
  }
  if (verso) spreads.push([verso, null]);
  const density = Math.min(window.devicePixelRatio || 1, 2);
  showPages.painter?.disconnect();
  const painter = new IntersectionObserver((entries) => {
    for (const { isIntersecting, target } of entries) {
      if (!isIntersecting) continue;
      painter.unobserve(target);
      const { doc, page } = target.postext;
      renderPageToCanvas(page, doc, target, { ...render, scale: (width * density) / page.width });
    }
  }, { rootMargin: '800px' });
  showPages.painter = painter;
  root.replaceChildren(...spreads.map((pair) => {
    const spread = document.createElement('div');
    spread.className = 'pt-spread';
    for (const p of pair) {
      const figure = document.createElement('figure');
      if (p) {
        const label = p.page.pageLabel || String(p.n + 1);
        const canvas = document.createElement('canvas');
        canvas.postext = p;
        canvas.style.aspectRatio = `${p.page.width} / ${p.page.height}`;
        canvas.setAttribute('role', 'img');
        canvas.setAttribute('aria-label', `Page ${label}`);
        const folio = document.createElement('figcaption');
        folio.textContent = label;
        figure.append(canvas, folio);
        painter.observe(canvas);
      } else figure.className = 'pt-blank';
      spread.append(figure);
    }
    return spread;
  }));
  kitStatus(`${pages.length} ${pages.length === 1 ? 'page' : 'pages'}`);
  document.documentElement.dataset.postext = 'ready';
  return pages.length;
}

/** The desk, the bar and the error reporting, created once. */
function viewer(title) {
  if (!document.getElementById('pt-kit')) {
    document.head.insertAdjacentHTML('beforeend', `<style id="pt-kit">
      :root { color-scheme: dark; }
      body { margin: 0; background: #0e1014; color: #b9bcc4; font: 13px/1.45 system-ui, sans-serif; }
      #pt-bar { position: sticky; top: 0; z-index: 1; display: flex; flex-wrap: wrap; align-items: center;
        gap: 6px 16px; padding: 10px 16px; background: rgb(14 16 20 / .92); backdrop-filter: blur(6px);
        border-bottom: 1px solid #23262d; }
      #pt-bar strong { color: #f4f1ea; font-weight: 600; }
      #pt-actions { display: flex; gap: 12px; margin-left: auto; }
      #pt-actions a, #pt-actions button { color: #d8a21a; font: inherit; background: none; border: 0; padding: 0; cursor: pointer; }
      #pages { display: grid; justify-items: center; gap: 48px; padding: 32px 16px 72px; }
      .pt-spread { display: flex; }
      .pt-spread figure { margin: 0; width: min(460px, 44vw); }
      .pt-spread canvas { display: block; width: 100%; background: #fff;
        box-shadow: 0 1px 2px rgb(0 0 0 / .5), 0 22px 44px -16px rgb(0 0 0 / .8); }
      .pt-spread figure:first-child canvas { box-shadow: inset -14px 0 14px -14px rgb(0 0 0 / .18), 0 1px 2px rgb(0 0 0 / .5), 0 22px 44px -16px rgb(0 0 0 / .8); }
      .pt-spread figcaption { margin-top: 10px; text-align: center; font: 600 10px/1 system-ui, sans-serif;
        letter-spacing: .18em; text-transform: uppercase; color: #6c7079; }
      .pt-blank { visibility: hidden; }
      @media (max-width: 760px) {
        .pt-spread { flex-direction: column; gap: 32px; }
        .pt-spread figure { width: min(460px, 92vw); }
        .pt-blank { display: none; }
      }
    </style>`);
    document.body.insertAdjacentHTML('afterbegin',
      '<header id="pt-bar"><strong id="pt-title"></strong><span id="pt-status" role="status"></span><span id="pt-actions"></span></header>');
    document.getElementById('pt-title').textContent = document.title || 'Postext';
    addEventListener('error', (event) => kitFail(event.error ?? event.message));
    addEventListener('unhandledrejection', (event) => kitFail(event.reason));
  }
  if (title) document.getElementById('pt-title').textContent = title;
  return document.getElementById('pages')
    ?? document.body.appendChild(Object.assign(document.createElement('main'), { id: 'pages' }));
}

function kitStatus(text) {
  viewer();
  document.getElementById('pt-status').textContent = text;
}

function kitFail(error) {
  document.documentElement.dataset.postext = 'error';
  kitStatus(`Error: ${error?.message ?? error}`);
}

// ─── Kit · pdf v3 ── the same in every recipe that exports a PDF
/** The Fontsource files the screen used, as TrueType, with their range and
 *  place: the nearest weight the family ships in that style, upright with no italic;
 *  latin, then what its letters need (kitSubsetsFor). */
async function fontsourceProvider(family, weight, style, request) {
  const id = fontsourceId(family);
  const meta = await fontsourceMeta(family);
  const s = style === 'italic' && meta && !meta.styles.includes('italic') ? 'normal' : style;
  const shipped = meta ? await fontsourceWeights(family, s) : [];
  const weights = shipped.length ? shipped : [400, 700];
  const w = weights.reduce((a, b) => (Math.abs(b - weight) < Math.abs(a - weight) ? b : a));
  const text = String.fromCodePoint(...(request?.codePoints ?? []));
  const files = await Promise.all(['latin', ...kitSubsetsFor(text, meta)].map(async (subset, order) => {
    const res = await fetch(`${await fontsourceAt(id)}files/${id}-${subset}-${w}-${s}.woff2`);
    if (!res.ok) throw new Error(`Fontsource has no ${family} ${w} ${s} ${subset}`);
    return Object.assign(await decompressWoff2(new Uint8Array(await res.arrayBuffer())),
      { unicodeRange: kitRanges()[subset], order });
  }));
  return files.length === 1 ? files[0] : files;
}

/** A "Build the PDF" button; then "Open the PDF" (a new tab: CodePen's frame
 *  shows no PDFs) and a download link. */
function offerPdf(makePdf, filename) {
  viewer();
  const button = Object.assign(document.createElement('button'), { type: 'button', textContent: 'Build the PDF' });
  button.dataset.postextPdf = filename;
  button.addEventListener('click', async () => {
    button.disabled = true;
    button.textContent = 'Building the PDF…';
    try {
      const bytes = await makePdf();
      const url = URL.createObjectURL(new Blob([bytes], { type: 'application/pdf' }));
      const size = `${Math.max(1, Math.round(bytes.length / 1024))} KB`;
      button.replaceWith(
        Object.assign(document.createElement('a'), { href: url, target: '_blank', rel: 'noopener', textContent: 'Open the PDF ↗' }),
        Object.assign(document.createElement('a'), { href: url, download: filename, textContent: `Download ${filename} · ${size}` }));
    } catch (error) {
      button.disabled = false;
      button.textContent = 'Build the PDF';
      kitFail(error);
    }
  });
  document.getElementById('pt-actions').append(button);
}

// ─── Kit · cjk v2 ── Chinese, Japanese and Korean books · postext.dev/cookbook
// Fontsource ships a CJK family as about a hundred files per weight, each
// declared in its stylesheet with the unicode-range it covers. The screen
// loads the files the sample touches; the PDF gets the same files for the
// characters its pages set in each face, and embeds each as a subset.
// A book bound on the right (vertical text) is shown with its spreads
// mirrored: page 1 alone on the left of the spine, then [3 | 2].

/** The files of a Fontsource face, read from its stylesheet: { url, range,
 *  ranges }, the last declared first (the order the browser tries them in). */
function cjkSlices(family, weight, style) {
  cjkSlices.cache ??= new Map();
  const id = fontsourceId(family);
  const css = `${id}/${weight}${style === 'italic' ? '-italic' : ''}.css`;
  if (!cjkSlices.cache.has(css)) {
    let at;
    cjkSlices.cache.set(css, fontsourceAt(id).then((a) => fetch(at = a + css.slice(id.length + 1)))
      .then((res) => {
        if (!res.ok) throw new Error(`Fontsource has no ${family} ${weight} ${style} (${res.status})`);
        return res.text();
      })
      .then((text) => [...text.matchAll(/@font-face\s*{([^}]*)}/g)].map(([, rule]) => {
        const range = /unicode-range:\s*([^;]+);/.exec(rule)?.[1].trim() ?? 'U+0-10FFFF';
        const ranges = range.split(',').map((part) => {
          const [lo, hi = lo] = part.trim().slice(2).split('-');
          return [parseInt(lo, 16), parseInt(hi, 16)];
        });
        return { url: new URL(/url\(([^)]+?\.woff2)\)/.exec(rule)[1], at).href, range, ranges };
      }).reverse()));
  }
  return cjkSlices.cache.get(css);
}

/** The file of `slices` the screen sets code point `cp` in, if any: the
 *  last one loadCjkFonts adds whose range holds it. A numbered file that
 *  repeats a letter of latin is added after latin, and wins it. */
function cjkSliceFor(slices, cp) {
  const holds = (slice) => slice.ranges.some(([lo, hi]) => cp >= lo && cp <= hi);
  return slices.reduce((last, slice) => (holds(slice) ? slice : last), undefined);
}

/** Whether Fontsource serves `family` as a Chinese, Japanese or Korean
 *  family (its subsets name the script). Fails when the API does not
 *  answer: a CJK face taken for a Latin one would paint in a system face. */
async function isCjkFamily(family) {
  const meta = await fontsourceMeta(family);
  if (!meta) throw new Error(`api.fontsource.org did not describe ${family}: reload to try again`);
  return !!meta.subsets?.some((subset) => /^(chinese|japanese|korean)/.test(subset));
}

/** faces = { 'Noto Serif TC': ['400', '700'] }, as for loadFonts: the
 *  whole FONTS object may be passed, its other families are left to
 *  loadFonts. Adds one FontFace per file of each CJK face with its
 *  unicodeRange, then loads the files `text` touches. `text` is what the
 *  faces set: the sample for the text face; a book in several voices calls
 *  it once per voice (loadCjkFonts({ 'LXGW WenKai TC': ['400'] }, quotes)),
 *  so the heading and quotation faces fetch and check only their own
 *  characters. Fails when a character of `text` is in no file of a face.
 *  List every weight the pages use: a weight left to the engine's later round
 *  gets the latin file only. With { vertical: true } it also loads each
 *  family's vertical forms (brackets, quotes, pause marks) for the canvas,
 *  which needs loadVerticalAlternates imported from postext. Resolves to
 *  the number of files loaded. */
async function loadCjkFonts(faces, text, { vertical = false } = {}) {
  kitStatus('Loading fonts…');
  let loaded = 0;
  try {
    if (vertical && typeof loadVerticalAlternates !== 'function') {
      throw new Error('loadCjkFonts(…, { vertical: true }) needs loadVerticalAlternates imported from postext');
    }
    for (const [family, specs] of Object.entries(faces)) {
      if (!(await isCjkFamily(family))) continue;
      const twin = [];
      for (const spec of new Set(specs)) {
        const weight = parseInt(spec, 10);
        const style = spec.endsWith('i') ? 'italic' : 'normal';
        const slices = await cjkSlices(family, weight, style);
        const missing = [...new Set(text)].filter((ch) => /\S/.test(ch) && !cjkSliceFor(slices, ch.codePointAt(0)));
        if (missing.length) {
          throw new Error(`${family} ${spec} has no file for ${missing.slice(0, 12).join(' ')}: `
            + `give each face the text it sets (loadCjkFonts({ '${family}': ['${spec}'] }, text))`);
        }
        for (const slice of slices) {
          document.fonts.add(new FontFace(family, `url(${slice.url}) format('woff2')`,
            { weight: String(weight), style, unicodeRange: slice.range }));
          twin.push({ source: slice.url, weight: String(weight), style, unicodeRange: slice.range });
        }
        const font = `${style === 'italic' ? 'italic ' : ''}${weight} 16px "${family}"`;
        loaded += (await document.fonts.load(font, text)).length;
        if (!document.fonts.check(font, text)) throw new Error(`${family} ${spec} did not load for the sample`);
      }
      // The same files under a twin name with the `vert` feature on: the
      // canvas paints the punctuation of vertical lines with it.
      if (vertical && twin.length) await loadVerticalAlternates(family, twin);
    }
  } catch (error) {
    kitFail(error);
    throw error;
  }
  return loaded;
}

/** The PDF font provider for recipes with CJK faces: a family whose
 *  Fontsource subsets are Chinese, Japanese or Korean gets the files the
 *  screen set its pages' characters in (`request.codePoints`), each marked
 *  with its unicode-range and its place in the order loadCjkFonts added
 *  them: postext-pdf sets a character two files hold in the one added
 *  last, as the browser does. Any other family gets the latin file
 *  fontsourceProvider fetches (the "pdf" block) and, when the face sets
 *  letters only latin-ext has, that file too. */
async function cjkPdfProvider(family, weight, style, request) {
  if (!(await isCjkFamily(family))) return cjkLatinPdfFiles(family, weight, style, request);
  const meta = await fontsourceMeta(family);
  const weights = meta.weights?.length ? meta.weights : [400, 700];
  const w = weights.reduce((a, b) => (Math.abs(b - weight) < Math.abs(a - weight) ? b : a));
  const s = style === 'italic' && !meta.styles.includes('italic') ? 'normal' : style;
  const slices = await cjkSlices(family, w, s);
  const picked = new Set();
  for (const cp of request?.codePoints ?? []) {
    const slice = cjkSliceFor(slices, cp);
    if (slice) picked.add(slice);
  }
  if (!picked.size) picked.add(slices[0]);
  return Promise.all(slices.map(async (slice, order) => {
    if (!picked.has(slice)) return null;
    const res = await fetch(slice.url);
    if (!res.ok) throw new Error(`Fontsource file ${slice.url} (${res.status})`);
    const bytes = await decompressWoff2(new Uint8Array(await res.arrayBuffer()));
    return Object.assign(bytes, { unicodeRange: slice.range, order });
  })).then((files) => files.filter(Boolean));
}

/** A Latin family set next to the CJK faces: its latin file, then its
 *  latin-ext file when the face sets letters only latin-ext has (ō ū in
 *  Hepburn rōmaji, ǎ in pinyin), the file loadFonts adds on screen for
 *  them, each marked with its unicode-range and its place in that order:
 *  the PDF sets a character in the file the browser took it from. A face
 *  Fontsource ships without latin-ext, or whose file does not come, gets
 *  latin alone, and the PDF names the letters it lacks. */
async function cjkLatinPdfFiles(family, weight, style, request) {
  const meta = await fontsourceMeta(family);
  const beyond = [...(request?.codePoints ?? [])].some(cjkLatinExtOnly);
  if (!beyond || !meta?.subsets?.includes('latin-ext')) return fontsourceProvider(family, weight, style);
  const weights = meta.weights?.length ? meta.weights : [400, 700];
  const w = weights.reduce((a, b) => (Math.abs(b - weight) < Math.abs(a - weight) ? b : a));
  const s = style === 'italic' && !meta.styles.includes('italic') ? 'normal' : style;
  const id = fontsourceId(family);
  const url = `${await fontsourceAt(id)}files/${id}-latin-ext-${w}-${s}.woff2`;
  const [latin, ext] = await Promise.all([fontsourceProvider(family, weight, style), fetch(url)
    .then(async (res) => (res.ok ? decompressWoff2(new Uint8Array(await res.arrayBuffer())) : null), () => null)]);
  const ranges = kitRanges();
  return ext ? [Object.assign(latin, { unicodeRange: ranges.latin, order: 0 }),
    Object.assign(ext, { unicodeRange: ranges['latin-ext'], order: 1 })] : latin;
}

/** Whether code point `cp` is in Fontsource's latin-ext file and not in
 *  its latin file: Latin Extended-A and -B, IPA, the spacing modifiers and
 *  Latin Extended Additional (loadFonts's test for latin-ext), less the
 *  few latin holds too (ı Œ œ ʻ ʼ ˆ ˚ ˜). */
function cjkLatinExtOnly(cp) {
  if (!((cp >= 0x100 && cp <= 0x2ff) || (cp >= 0x1e00 && cp <= 0x1eff))) return false;
  return ![0x131, 0x152, 0x153, 0x2bb, 0x2bc, 0x2c6, 0x2da, 0x2dc].includes(cp);
}

/** showPages for a book bound on either edge. A right-bound book (the
 *  document says so: doc.binding is 'right' for page.binding 'right' and
 *  for vertical text) lies on the desk as it opens: page 1 alone on the
 *  left of the spine, then [3 | 2], the spine shade on each page's inner
 *  edge. `binding` ('left' | 'right') overrides the document's. */
function showBook(docs, { binding, ...options } = {}) {
  const count = showPages(docs, options);
  const right = (binding ?? [docs].flat()[0]?.binding) === 'right';
  if (!document.getElementById('pt-kit-cjk')) {
    // The pages keep direction ltr: a canvas draws text in the direction its
    // element inherits, and under rtl each run would end where the engine
    // starts it, its brackets mirrored.
    document.head.insertAdjacentHTML('beforeend', `<style id="pt-kit-cjk">
      .pt-spread[dir="rtl"] canvas { direction: ltr; }
      .pt-spread[dir="rtl"] figure:first-child canvas { box-shadow: inset 14px 0 14px -14px rgb(0 0 0 / .18),
        0 1px 2px rgb(0 0 0 / .5), 0 22px 44px -16px rgb(0 0 0 / .8); }
    </style>`);
  }
  // Each pair stays [verso, recto] in the page; right to left, the verso
  // sits on the right. Phones stack the pages in reading order either way.
  for (const spread of document.querySelectorAll('#pages > .pt-spread')) spread.dir = right ? 'rtl' : 'ltr';
  document.getElementById('pages').dataset.binding = right ? 'right' : 'left';
  return count;
}

// ─── Kit · arabic v2 ── Arabic-script faces · postext.dev/cookbook
// Fontsource ships an Arabic family as one file per subset and weight: the
// `arabic` file holds the letters, the harakat, the Arabic-Indic digits, the
// Arabic punctuation and the presentation forms; `latin` and `latin-ext`
// hold the rest. loadFonts loads the latin files; this block adds the arabic
// file of every Arabic family, for the canvas and for the PDF, which shapes
// the letters with HarfBuzz from the same bytes.

/** The code points of Fontsource's `arabic` subset, as its stylesheets
 *  declare them (the same unicode-range the browser picks the file by). A
 *  function, not a const: the kit is inlined after the recipe's top-level
 *  awaits, and a const read before its line throws, where a function
 *  declaration is hoisted. */
function arabicRange() {
  return 'U+0600-06FF,U+0750-077F,U+0870-088E,U+0890-0891,U+0897-08E1,U+08E3-08FF,'
    + 'U+200C-200E,U+2010-2011,U+204F,U+2E41,U+FB50-FDFF,U+FE70-FE74,U+FE76-FEFC,U+102E0-102FB,'
    + 'U+10E60-10E7E,U+10EC2-10EC4,U+10EFC-10EFF,U+1EE00-1EEFF';
}

/** Whether code point `cp` is in the arabic file. */
function inArabicRange(cp) {
  inArabicRange.ranges ??= arabicRange().split(',').map((part) => {
    const [lo, hi = lo] = part.slice(2).split('-');
    return [parseInt(lo, 16), parseInt(hi, 16)];
  });
  return inArabicRange.ranges.some(([lo, hi]) => cp >= lo && cp <= hi);
}

/** Whether Fontsource serves `family` with an `arabic` subset. Fails when
 *  the API does not answer: an Arabic face taken for a Latin one would set
 *  its letters in a system face. */
async function isArabicFamily(family) {
  const meta = await fontsourceMeta(family);
  if (!meta) throw new Error(`api.fontsource.org did not describe ${family}: reload to try again`);
  return !!meta.subsets?.includes('arabic');
}

/** The arabic file of a face. */
async function arabicFileUrl(family, weight, style) {
  const id = fontsourceId(family);
  return `${await fontsourceAt(id)}files/${id}-arabic-${weight}-${style}.woff2`;
}

/** faces = { Amiri: ['400', '700'] }, as for loadFonts, after it: the whole
 *  FONTS object may be passed, its families without an arabic subset are
 *  left alone. Adds the arabic file of every listed weight of each Arabic
 *  family (the latin files come from loadFonts) and loads it. `text` is
 *  the sample: fails when it holds an Arabic-script character the arabic
 *  file does not cover. List every weight the pages set in Arabic: a weight
 *  left to the engine's later round gets the latin file only, and its Arabic letters
 *  fall back to a system face. Resolves to the number of files loaded. */
async function loadArabicFonts(faces, text = '') {
  kitStatus('Loading fonts…');
  let loaded = 0;
  try {
    const outside = [...new Set(text)].filter((ch) => /\p{Script=Arabic}/u.test(ch) && !inArabicRange(ch.codePointAt(0)));
    if (outside.length) throw new Error(`Fontsource's arabic files have no ${outside.slice(0, 12).join(' ')}`);
    for (const [family, specs] of Object.entries(faces)) {
      if (!(await isArabicFamily(family))) continue;
      for (const spec of new Set(specs)) {
        const weight = parseInt(spec, 10);
        const style = spec.endsWith('i') ? 'italic' : 'normal';
        const face = new FontFace(family, `url(${await arabicFileUrl(family, weight, style)}) format('woff2')`,
          { weight: String(weight), style, unicodeRange: arabicRange() });
        document.fonts.add(await face.load().catch(() => {
          throw new Error(`Fontsource has no arabic file for ${family} ${weight} ${style}`);
        }));
        loaded++;
      }
    }
  } catch (error) {
    kitFail(error);
    throw error;
  }
  return loaded;
}

/** The PDF font provider for recipes with Arabic faces: a family with an
 *  arabic subset gets its arabic file when its pages set Arabic letters
 *  (`request.codePoints`), then its latin file, and its latin-ext file for
 *  the letters beyond latin (transliteration: ā ḥ ʿ), each marked with its
 *  unicode-range and its place in the order the screen added them (latin
 *  and latin-ext by loadFonts, then arabic): the arabic file also has a
 *  space and brackets, which the browser takes from latin, the file whose
 *  range holds them, and postext-pdf follows it. Any other family goes to
 *  fontsourceProvider (the "pdf" block). */
async function arabicPdfProvider(family, weight, style, request) {
  if (!(await isArabicFamily(family))) return fontsourceProvider(family, weight, style, request);
  const meta = await fontsourceMeta(family);
  const weights = meta.weights?.length ? meta.weights : [400, 700];
  const w = weights.reduce((a, b) => (Math.abs(b - weight) < Math.abs(a - weight) ? b : a));
  const s = style === 'italic' && !meta.styles.includes('italic') ? 'normal' : style;
  const wanted = [...(request?.codePoints ?? [])];
  const id = fontsourceId(family);
  const subsets = !wanted.length || wanted.some(inArabicRange) ? ['arabic', 'latin'] : ['latin'];
  if (meta.subsets.includes('latin-ext') && wanted.some((cp) => /[Ā-˿Ḁ-ỿ]/u.test(String.fromCodePoint(cp)))) {
    subsets.push('latin-ext');
  }
  const at = await fontsourceAt(id);
  return Promise.all(subsets.map(async (subset) => {
    const url = `${at}files/${id}-${subset}-${w}-${s}.woff2`;
    const res = await fetch(url);
    if (!res.ok) throw new Error(`Fontsource file ${url} (${res.status})`);
    const bytes = await decompressWoff2(new Uint8Array(await res.arrayBuffer()));
    return Object.assign(bytes, { unicodeRange: subset === 'arabic' ? arabicRange() : kitRanges()[subset],
      order: ['latin', 'latin-ext', 'greek', 'arabic'].indexOf(subset) });
  }));
}

// ─── /Kit ───────────────────────────────────────────────────────────────────────
```

## Varianti

### Stampa la copia dell’insegnante

Ogni risposta va al suo posto in magenta: le parentesi, le caselle, gli spazi e il quoziente.

```diff
   exerciseStyles: [ficha],
+  exercises: { edition: 'teacher' },
```

### Raccogli le soluzioni in fondo alla scheda

`placement: 'after'` mette la chiave di ogni esercizio sotto di esso; `'inverted'` la capovolge, come nelle pagine di enigmistica.

```diff
+  exercises: { solutions: { placement: 'inverted', layout: 'key' } },
```

## Errori frequenti

- Un font senza peso 700 rende sintetico il grassetto dei numeri delle consegne. Dai a quel font di testo un `boldFontWeight` con un peso che possiede.
- Il ○ delle consegne giapponesi e il √ di quelle cinesi esistono solo nei font CJK: mettili in una frase del testo CJK, non in un’etichetta latina.

## Crediti

- Ricetta: Ignacio Ferro ([@drnachio](https://github.com/drnachio))
- Caratteri: Nunito (OFL-1.1), Baloo 2 (OFL-1.1), Noto Serif SC (OFL-1.1), Noto Sans SC (OFL-1.1), Klee One (OFL-1.1), Noto Sans JP (OFL-1.1), Noto Naskh Arabic (OFL-1.1), Baloo Bhaijaan 2 (OFL-1.1)
- Codice: MIT · Contenuto di esempio: CC-BY-4.0

## Ricette correlate

- [Nº 171 · Un quaderno di esercizi cinese, per alunno e insegnante](https://postext.dev/it/cookbook/chinese-exercise-book.md): Un 练习册 di cinese e matematica: sezioni 一、二、, parentesi （　）, 田字格 e operazioni in colonna, composto due volte da un solo testo, per l’alunno e l’insegnante. · Livello 2 (Intermedio) · Quaderni ed eserciziari, Libri di testo
- [Nº 172 · Esercizi giapponesi con le soluzioni capovolte](https://postext.dev/it/cookbook/japanese-drill-upside-down-answers.md): Due pagine di una serie di quaderni di esercizi giapponesi, l’aritmetica in orizzontale e i kanji in colonna, con le soluzioni capovolte sotto ogni esercizio. · Livello 2 (Intermedio) · Quaderni ed eserciziari, Libri di testo
- [Nº 173 · Un quaderno di esercizi arabo, da destra a sinistra](https://postext.dev/it/cookbook/arabic-workbook-rtl.md): Un quaderno arabo per la primaria da destra a sinistra: opzioni أ ب ج, colonne da collegare, riquadro di parole, صح o خطأ, crucipuzzle e cifre arabo-indiane. · Livello 2 (Intermedio) · Quaderni ed eserciziari, Libri di testo