# منصّة لتجربة إعدادات العارض Folio

> نموذج يضم كل إعدادات config.folio يقود عارض postext-folio واحدًا عبر setAppearance: الورق والتجليد والغلافان والمكتب والإضاءة والميل تتغيّر في مكانها.

- نسخة HTML: https://postext.dev/ar/cookbook/folio-settings-bench
- وصفة رقم 103 · الإخراج والدمج · المستوى 2 (متوسط) · المخرجات: Canvas, عناصر تحكم حية
- الأنواع: الأدلة والمراجع
- تتطلب postext ≥ 1.13.4 · اختُبرت مع 1.13.4 بتاريخ 2026-10-04
- الصفحات: [1](https://postext.dev/cookbook/folio-settings-bench/en/p01.webp?v=4789c235), [2](https://postext.dev/cookbook/folio-settings-bench/en/p02.webp?v=4789c235), [3](https://postext.dev/cookbook/folio-settings-bench/en/p03.webp?v=4789c235), [4](https://postext.dev/cookbook/folio-settings-bench/en/p04.webp?v=4789c235), [5](https://postext.dev/cookbook/folio-settings-bench/en/p05.webp?v=4789c235), [6](https://postext.dev/cookbook/folio-settings-bench/en/p06.webp?v=4789c235), [7](https://postext.dev/cookbook/folio-settings-bench/en/p07.webp?v=4789c235), [8](https://postext.dev/cookbook/folio-settings-bench/en/p08.webp?v=4789c235), [9](https://postext.dev/cookbook/folio-settings-bench/en/p09.webp?v=4789c235), [10](https://postext.dev/cookbook/folio-settings-bench/en/p10.webp?v=4789c235)
- افتح في Sandbox: https://postext.dev/ar/sandbox#recipe=folio-settings-bench&lang=en (.postext: https://postext.dev/cookbook/folio-settings-bench/en/folio-settings-bench.postext)
- آخر تحديث: 2026-10-04
- لغات أخرى: [en](https://postext.dev/en/cookbook/folio-settings-bench.md), [es](https://postext.dev/es/cookbook/folio-settings-bench.md), [ca](https://postext.dev/ca/cookbook/folio-settings-bench.md), [zh](https://postext.dev/zh/cookbook/folio-settings-bench.md)

## باختصار

كتاب جيب صغير معروض بالأبعاد الثلاثة بجانب لوحة من أدوات التحكم. غيّر الورق أو التجليد أو المكتب أو الإضاءة فيتغيّر الكتاب فورًا، دون أن يُنضَّد من جديد.

## ما الذي ستنضده

*Six Knots* كتاب جيب من عشر صفحات بقياس قص 110 × 160 mm، مفتوح في Folio بجانب لوحة تضم كل إعدادات `config.folio`. اختر نوع ورق فتتغيّر الأوراق لونًا وسطحًا وصلابة؛ وبدّل التجليد من غلاف ورقي إلى غلاف مقوّى فتنمو علبة حول كتلة الصفحات؛ واختر العلبة بدل الغلافين المطبوعين، وخامة من القماش أو الجلد، ومكتبًا، وإضاءة، وميلًا. يُنضَّد الكتاب مرة واحدة. ويصل كل تغيير إلى العارض عبر `setAppearance`، فلا يتحرّك أي سطر ولا تُرسم أي صفحة من جديد، وتظهر الإعدادات تحت النموذج كودًا جاهزًا للصق في `config.folio`.

**تجيب هذه الوصفة عن:**

- كيف أعاين تجليد الكتاب وغلافه وورقه وإضاءته قبل أن يُطبع؟
- كيف أعرض مستندي كتابًا ثلاثي الأبعاد يقلّب القارئ صفحاته بيده؟

## الجواب المختصر

```js
// script.js, سطرًا 196–220
const book = createFolioFromDocument(document.getElementById('folio'), doc, {
  // The look starts from doc.config.folio; setAppearance replaces it on every change.
  appearance: { textureBaseUrl: 'https://postext.dev/folio/textures' },
  onChange: ({ pages }) => kitStatus(`${doc.pages.length} pages · open at `
    + pages.map((i) => i + 1).join('–')),
});
function update() {
  const folio = folioOf();
  // Only the appearance changes: the pages keep their paintings, nothing is laid out again.
  book.setAppearance({ folio });
  show('grammage-out', `${folio.paper.grammage} g/m²`);
  show('intensity-out', folio.lighting.intensity.toFixed(2));
  show('tilt-out', `${folio.tilt}°`);
  document.getElementById('folio-json').textContent = `folio: ${JSON.stringify(folio, null, 2)}`;
}
form.addEventListener('input', update);
// A stock sets its own weight: picking one moves the weight slider to the stock's.
const WEIGHTS = { uncoated: 90, bookWove: 80, coatedMatte: 115, coatedSilk: 115,
  coatedGloss: 115, bible: 40, newsprint: 48, cardStock: 250 };
form.elements['paper.type'].addEventListener('change', (event) => {
  form.elements['paper.grammage'].value = WEIGHTS[event.target.value];
  update();
});
document.getElementById('reset-view').addEventListener('click', () => book.resetView());
update();
```

## المكونات

**تعلّم**

- [الورق والتجليد والمكتب والإضاءة (Folio)](https://postext.dev/ar/docs/configuration.md#عارض-folio-الإعدادات): يحدّد config.folio كيف يُصنع الكتاب ثلاثي الأبعاد ويُضاء: نوع الورق ووزنه، والتجليد والأغلفة، والسطح الذي تحته، والإضاءة.
- [عارض الكتاب ثلاثي الأبعاد (Folio)](https://postext.dev/ar/docs/configuration.md#كتاب-ثلاثي-الأبعاد-postext-folio): يفتح postext-folio المستند المُخرَج كتابًا مطبوعًا على مكتب: صفحتان متقابلتان وفق قاعدة الصفحة الفردية، وأوراق يقلّبها القارئ بيده.

**تستخدم أيضًا**

- [أنماط العناوين](https://postext.dev/ar/docs/configuration.md#أنماط-العناوين)
- [صفحات افتتاح مصمَّمة](https://postext.dev/ar/docs/configuration.md#الامتداد-والتصميم-المتقدم)
- [سمات العنوان](https://postext.dev/ar/docs/document-format.md#سمات-العناوين)
- [أنماط الفقرات](https://postext.dev/ar/docs/configuration.md#أنماط-الفقرات)
- [الترويسات بحسب دور الصفحة](https://postext.dev/ar/docs/configuration.md#عناصر-النص)
- [لوحة ألوان دلالية](https://postext.dev/ar/docs/configuration.md#لوحة-الألوان)
- [هوامش متناظرة](https://postext.dev/ar/docs/configuration.md#الهوامش-المتناظرة)
- [صفحات على اللوحة (Canvas)](https://postext.dev/ar/docs/configuration.md#رسم-صفحة-في-صورة-نقطية)
- [هندسة القسم](https://postext.dev/ar/docs/configuration.md#أنماط-العناوين)
- [ترويسات لكل قسم](https://postext.dev/ar/docs/configuration.md#أنماط-العناوين)
- [فصول بلا أرقام](https://postext.dev/ar/docs/configuration.md#أنماط-العناوين)

**الإعدادات في لمحة**

- [`bodyText`](https://postext.dev/ar/docs/configuration.md#نص-المتن), [`colorPalette`](https://postext.dev/ar/docs/configuration.md#لوحة-الألوان), `folio`, [`footer`](https://postext.dev/ar/docs/configuration.md#رؤوس-الصفحات-وتذييلاتها), [`header`](https://postext.dev/ar/docs/configuration.md#رؤوس-الصفحات-وتذييلاتها), [`headingStyles`](https://postext.dev/ar/docs/configuration.md#أنماط-العناوين), [`headings`](https://postext.dev/ar/docs/configuration.md#العناوين), [`layout`](https://postext.dev/ar/docs/configuration.md#التخطيط), [`locale`](https://postext.dev/ar/docs/configuration.md#تقسيم-الكلمات-بالواصلة), [`page`](https://postext.dev/ar/docs/configuration.md#الصفحة), [`paragraphStyles`](https://postext.dev/ar/docs/configuration.md#أنماط-الفقرات)

**واجهات API**

- [`buildDocument`](https://postext.dev/ar/docs/configuration.md#بناء-مستند), [`clearMeasurementCache`](https://postext.dev/ar/docs/configuration.md#ذاكرة-القياس-المؤقتة), [`createFolioFromDocument`](https://postext.dev/ar/docs/configuration.md#كتاب-ثلاثي-الأبعاد-postext-folio), [`renderPageToCanvas`](https://postext.dev/ar/docs/configuration.md#رسم-صفحة-في-صورة-نقطية)

**الخطوط**

- Source Serif 4 (OFL-1.1), Outfit (OFL-1.1)

## طريقة التحضير

### 1 · سمِّ الحقول بأسماء الإعدادات

```js
// script.js, سطرًا 72–86
const form = document.getElementById('controls');
const hex = (value) => ({ hex: value, model: 'hex' });
function folioOf() { // 'paper.grammage' → { paper: { grammage } }, typed by the input
  const folio = {};
  for (const el of form.elements) {
    if (!el.name || el.type === 'button' || el.tagName === 'OUTPUT') continue;
    const value = el.type === 'checkbox' ? el.checked : el.type === 'range' ? Number(el.value)
      : el.type === 'color' ? hex(el.value) : el.value;
    const [group, key] = el.name.split('.');
    if (key) (folio[group] ??= {})[key] = value;
    else folio[group] = value;
  }
  return folio;
}
const show = (name, value) => { form.elements[name].value = value; };
```

يحمل كل حقل في النموذج اسم مساره في `config.folio` (`paper.grammage` و`binding.cover` و`lighting.environment`)، فتحوّل حلقة واحدة النموذج إلى الكائن الذي يأخذه العارض: أرقام من المنزلقات، وقيم منطقية من مربعات الاختيار، ولون `{ hex, model }` من أداة اختيار اللون. والكائن نفسه هو `config.folio` الخاص بالمستند حين يبنيه المثال، فيفتح Sandbox الكتاب كما يبدأ النموذج.

### 2 · غلافان يقلّبهما العارض لوحين

```js
// script.js, سطرًا 40–61
const field = { kind: 'box', id: 'field', style: { backgroundColor: col('brick') },
  placement: { ...at('bleed', 'top-left'), size: { width: 'fill', height: mm(TRIM_H) } } };
const flush = { numbered: false, span: 'page', footer: { elements: [] },
  margins: { top: mm(0), bottom: mm(0), left: mm(0), right: mm(0) } };
const cover = (id, title, extra = {}) => ({ id, ...flush, ...extra, advancedDesign: {
  enabled: true, minHeight: mm(TRIM_H), slot: { elements: [field, ...title] } } });
const headingStyles = [
  cover('cover', [
    text('title', '{titleText}', { fontFamily: SANS, fontWeight: 700, fontSize: pt(40),
      lineHeight: 0.92, color: col('cream') },
    { ...at('page', 'top-left', INNER, 30), size: { width: mm(80) } }),
    text('strap', '{attr.strap}', { fontFamily: 'Source Serif 4', italic: true,
      fontSize: pt(11), lineHeight: 1.3, color: col('cream') },
    { ...at('#title', 'below', 0, 6), size: { width: mm(72) } }),
    text('author', '{author}', caps(7, col('cream')), at('page', 'bottom-left', INNER, -16)),
  ]),
  cover('back', [
    text('strap', '{attr.strap}', { fontFamily: 'Source Serif 4', italic: true,
      fontSize: pt(11), lineHeight: 1.3, color: col('cream'), align: 'center' },
    { ...at('page', 'center', 0, 0), size: { width: mm(76) } }),
  ], { breakBefore: { enabled: true, parity: 'even' } }), // the back: always a verso
];
```

مع `binding.cover: 'pages'` تكون الصفحة الأولى اللوح الأمامي والأخيرة اللوح الخلفي، إذا وقعت على صفحة زوجية. يبدأ أسلوب عنوان الغلاف الخلفي على صفحة زوجية، فينتهي الكتاب دائمًا على صفحة زوجية ويُقلَّب الغلافان كلاهما. وإذا بدّلت النموذج إلى *A case round the pages* (علبة حول الصفحات) قُلِّبت الصفحتان نفساهما ورقتين عاديتين داخل علبة من القماش.

### 3 · أعِد تنسيق الكتاب في مكانه

الكود هو [الجواب المختصر](#الجواب-المختصر) أعلاه. تستبدل `setAppearance({ folio })` إعدادات المستند وتعيد رسم المشهد: سماكة الورق وصلابته، والعلبة، وخرائط المكتب، والإضاءة. تحتفظ الصفحات برسومها، فيظهر التغيير في الإطار التالي. لكل نوع ورق وزنه الخاص، ولهذا يحرّك اختيار نوع منزلقَ الوزن؛ وتعيد `resetView()` الكاميرا إلى مكانها بعد أن يدير القارئ الكتاب بالسحب بالزر الأيمن.

## الوصفة كاملة

تُركَّب الملفات أدناه من مجلد الوصفة، ومعها نص المثال وأدوات دليل الوصفات المشتركة مضمّنة. لتشغيلها صفحةً واحدة، ضع HTML داخل `<body>`، وCSS داخل عنصر `<style>`، والسكربت داخل `<script type="module">`؛ أو الصق كلًّا منها في اللوحة المقابلة من مثال CodePen جديد (مع ضبط JS وحدةً). يستورد السكربت postext من esm.sh، فلا حاجة إلى تثبيت أو بناء.

- مجلد الوصفة: https://github.com/drnachio/postext/tree/main/cookbook/folio-settings-bench

### index.html

```html
<section id="bench">
  <div id="folio" role="region" aria-label="The book in 3D"></div>
  <form id="controls" aria-label="Folio settings">
    <fieldset>
      <legend>Paper</legend>
      <label>Stock <select name="paper.type">
        <option value="uncoated">Uncoated</option><option value="bookWove" selected>Book wove</option>
        <option value="coatedMatte">Coated matte</option><option value="coatedSilk">Coated silk</option>
        <option value="coatedGloss">Coated gloss</option><option value="bible">Bible</option>
        <option value="newsprint">Newsprint</option><option value="cardStock">Card</option>
      </select></label>
      <label>Weight <output name="grammage-out">80 g/m²</output>
        <input type="range" name="paper.grammage" min="30" max="300" step="5" value="80"></label>
      <label>Texture <select name="paper.texture">
        <option value="auto" selected>The stock’s</option><option value="smooth">Smooth</option>
        <option value="vellum">Vellum</option><option value="wove">Wove</option>
        <option value="laid">Laid</option><option value="linen">Linen</option>
        <option value="felt">Felt</option>
      </select></label>
      <label class="check"><input type="checkbox" name="paper.showThrough" checked> Show-through</label>
    </fieldset>
    <fieldset>
      <legend>Binding</legend>
      <label>Type <select name="binding.type">
        <option value="hardcover">Hardcover</option><option value="paperback" selected>Paperback</option>
        <option value="sewn">Sewn softcover</option><option value="layflat">Lay-flat</option>
        <option value="saddleStitch">Saddle stitch</option>
      </select></label>
      <label>Covers <select name="binding.cover">
        <option value="pages" selected>The first and last pages</option>
        <option value="case">A case round the pages</option>
      </select></label>
      <label>Material <select name="binding.coverMaterial">
        <option value="auto" selected>The binding’s</option><option value="cloth">Cloth</option>
        <option value="paper">Paper</option><option value="leather">Leather</option>
      </select></label>
      <label>Colour <input type="color" name="binding.coverColor" value="#9a3b2e"></label>
    </fieldset>
    <fieldset>
      <legend>Desk and light</legend>
      <label>Surface <select name="surface.type">
        <option value="oak" selected>Oak</option><option value="walnut">Walnut</option>
        <option value="linen">Linen</option><option value="felt">Felt</option>
        <option value="leather">Leather</option><option value="marble">Marble</option>
        <option value="plain">Plain</option><option value="none">None</option>
      </select></label>
      <label>Light <select name="lighting.environment">
        <option value="studio">Studio</option><option value="daylight" selected>Daylight</option>
        <option value="lamp">Lamp</option><option value="overcast">Overcast</option>
        <option value="night">Night</option>
      </select></label>
      <label>Intensity <output name="intensity-out">1.0</output>
        <input type="range" name="lighting.intensity" min="0.25" max="2" step="0.05" value="1"></label>
      <label class="check"><input type="checkbox" name="lighting.shadows" checked> Shadows</label>
      <label>Tilt <output name="tilt-out">22°</output>
        <input type="range" name="tilt" min="0" max="40" step="1" value="22"></label>
      <button type="button" id="reset-view">Reset view</button>
    </fieldset>
    <pre id="folio-json" aria-label="The folio settings as code"></pre>
  </form>
</section>
<main id="pages"></main>
```

### style.css

```css
/* The bench: the book on the left, the settings on the right, the flat pages below. */
#bench {
  display: grid; grid-template-columns: minmax(0, 1fr) 300px; gap: 16px;
  max-width: 1320px; margin: 0 auto; padding: 16px; box-sizing: border-box;
  color: #c9ccd3; font: 13px/1.4 system-ui, sans-serif;
}
#folio { height: min(80vh, 760px); min-height: 420px; }
#controls { display: grid; gap: 12px; align-content: start; }
#controls fieldset {
  display: grid; gap: 8px; margin: 0; padding: 10px 12px 12px;
  border: 1px solid #2a2e36; border-radius: 6px;
}
#controls legend {
  padding: 0 4px; color: #f0b35a; font-weight: 600; font-size: 11px;
  letter-spacing: .12em; text-transform: uppercase;
}
#controls label { display: grid; grid-template-columns: 1fr auto; gap: 4px 8px; align-items: center; }
#controls label > select, #controls label > input[type="range"] { grid-column: 1 / -1; }
#controls label.check { display: flex; gap: 8px; }
#controls select, #controls button {
  min-height: 32px; padding: 4px 8px; border: 1px solid #3a3f49; border-radius: 4px;
  background: #1a1d23; color: #eceef2; font: inherit;
}
#controls input[type="color"] {
  width: 44px; height: 32px; padding: 0; border: 1px solid #3a3f49; border-radius: 4px;
  background: none;
}
#controls input[type="range"] { accent-color: #f0b35a; }
#controls output { color: #8d9199; font-variant-numeric: tabular-nums; }
#controls button { cursor: pointer; }
#controls button:hover, #controls button:focus-visible { border-color: #f0b35a; }
#folio-json {
  margin: 0; padding: 10px 12px; max-height: 220px; overflow: auto; border-radius: 6px;
  background: #15171c; color: #aeb3bd; font: 11.5px/1.45 ui-monospace, Menlo, monospace;
}
@media (max-width: 860px) {
  #bench { grid-template-columns: minmax(0, 1fr); }
  #folio { height: 70vh; }
}
```

### script.js

```js
// ═══ Postext Cookbook · Nº 103 · A bench for the Folio viewer's settings ═══════════════
// https://postext.dev/en/cookbook/folio-settings-bench
// Code: MIT · Text: original (CC BY 4.0) · Pictures: none
// Fonts: Source Serif 4, Outfit (SIL OFL 1.1) · Needs postext ≥ 1.13.4
//
// A pocket book of knots, laid out once and opened in postext-folio next to a form of every
// folio setting: paper, binding, covers, desk, light and tilt. Each change goes to the viewer
// with setAppearance, so the book is redrawn in place and no page is laid out or painted
// again. The settings as code sit under the form, ready to paste into config.folio.
import { buildDocument, renderPageToCanvas, clearMeasurementCache } from 'https://esm.sh/postext';
import { createFolioFromDocument } from 'https://esm.sh/postext-folio';

const LANG = 'en'; // @lang: the language of the sample document ('en' | 'es')
const RECIPE = 'folio-settings-bench';

// ─── 1 · Design ─────────────────────────────────────────────────────────────
// #region palette: brick red for the covers and the knot numbers, a warm ink for the text
const palette = {
  ink: '#24211f',
  brick: '#9a3b2e', // the cover field, kickers and folios
  cream: '#f6efe2', // type on the covers
  muted: '#6f6860',
};
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.brick, model: 'hex' } },
];
// #endregion
const [TRIM_W, TRIM_H, TOP, BOTTOM, INNER, OUTER] = [110, 160, 15, 17, 14, 12]; // mm: a pocket
const LEAD = 12.4; // pt
const SANS = 'Outfit';
const at = (to, edge, x = 0, y = 0) => ({ anchor: { to, edge }, offset: { x: mm(x), y: mm(y) } });
const text = (id, content, look, placement) => ({ kind: 'text', id, content, overflow: 'wrap',
  align: 'left', placement, ...look });
const caps = (size, color) => ({ fontFamily: SANS, fontSize: pt(size), fontWeight: 600,
  letterSpacing: pt(size * 0.16), textTransform: 'uppercase', color });

// #region covers: a full-page colour field on page 1 and on the last page
const field = { kind: 'box', id: 'field', style: { backgroundColor: col('brick') },
  placement: { ...at('bleed', 'top-left'), size: { width: 'fill', height: mm(TRIM_H) } } };
const flush = { numbered: false, span: 'page', footer: { elements: [] },
  margins: { top: mm(0), bottom: mm(0), left: mm(0), right: mm(0) } };
const cover = (id, title, extra = {}) => ({ id, ...flush, ...extra, advancedDesign: {
  enabled: true, minHeight: mm(TRIM_H), slot: { elements: [field, ...title] } } });
const headingStyles = [
  cover('cover', [
    text('title', '{titleText}', { fontFamily: SANS, fontWeight: 700, fontSize: pt(40),
      lineHeight: 0.92, color: col('cream') },
    { ...at('page', 'top-left', INNER, 30), size: { width: mm(80) } }),
    text('strap', '{attr.strap}', { fontFamily: 'Source Serif 4', italic: true,
      fontSize: pt(11), lineHeight: 1.3, color: col('cream') },
    { ...at('#title', 'below', 0, 6), size: { width: mm(72) } }),
    text('author', '{author}', caps(7, col('cream')), at('page', 'bottom-left', INNER, -16)),
  ]),
  cover('back', [
    text('strap', '{attr.strap}', { fontFamily: 'Source Serif 4', italic: true,
      fontSize: pt(11), lineHeight: 1.3, color: col('cream'), align: 'center' },
    { ...at('page', 'center', 0, 0), size: { width: mm(76) } }),
  ], { breakBefore: { enabled: true, parity: 'even' } }), // the back: always a verso
];
// #endregion

const opener = { enabled: true, minHeight: mm(22), slot: { elements: [
  text('kicker', '{attr.kicker}', caps(6.8, col('brick')), at('container', 'top-left', 0, 1)),
  text('title', '{titleText}', { fontFamily: SANS, fontWeight: 600, fontSize: pt(19),
    lineHeight: 1, color: col('ink') },
  { ...at('#kicker', 'below', 0, 2), size: { width: 'fill' } }),
] } };

// #region form: the form's fields (index.html) are named by their path in config.folio
const form = document.getElementById('controls');
const hex = (value) => ({ hex: value, model: 'hex' });
function folioOf() { // 'paper.grammage' → { paper: { grammage } }, typed by the input
  const folio = {};
  for (const el of form.elements) {
    if (!el.name || el.type === 'button' || el.tagName === 'OUTPUT') continue;
    const value = el.type === 'checkbox' ? el.checked : el.type === 'range' ? Number(el.value)
      : el.type === 'color' ? hex(el.value) : el.value;
    const [group, key] = el.name.split('.');
    if (key) (folio[group] ??= {})[key] = value;
    else folio[group] = value;
  }
  return folio;
}
const show = (name, value) => { form.elements[name].value = value; };
// #endregion

const config = () => ({ // a factory: the engine caches resolved configs per object
  locale: 'en-us',
  colorPalette,
  page: { sizePreset: 'custom', width: mm(TRIM_W), height: mm(TRIM_H), dpi: 150,
    margins: { top: mm(TOP), bottom: mm(BOTTOM), left: mm(INNER), right: mm(OUTER),
      mirror: true } },
  layout: { layoutType: 'single' },
  bodyText: { fontFamily: 'Source Serif 4', fontSize: pt(9.3), lineHeight: pt(LEAD),
    color: col('ink'), boldColor: col('ink'), italicColor: col('ink'),
    referenceColor: col('ink'), textAlign: 'justify', firstLineIndent: mm(3.5),
    indentAfterHeading: false, hyphenation: { enabled: true }, optimalLineBreaking: true,
    avoidWidows: true, avoidOrphans: true, avoidRunts: true },
  headings: { fontFamily: SANS, color: col('ink'), fontWeight: 600, levels: [
    // Restated: any headings object drops the H1 break (gotcha: headings-drop-h1-break).
    { level: 1, fontSize: pt(19), breakBefore: { enabled: true, parity: 'any' },
      marginBottom: pt(LEAD / 2), advancedDesign: opener },
  ] },
  headingStyles,
  paragraphStyles: [{ id: 'colophon', fontFamily: SANS, fontSize: pt(6.5), lineHeight: pt(9),
    color: col('muted'), textAlign: 'left', firstLineIndent: pt(0), marginTop: pt(LEAD) }],
  header: { elements: [] },
  folio: folioOf(), // the form's starting settings: the document's own look in the Sandbox
  footer: { elements: [text('folio', '{pageNumber}', { ...caps(6.5, col('brick')),
    align: 'center' }, at('page', 'bottom', 0, -9))] },
});

// ─── 2 · Content ────────────────────────────────────────────────────────────
const markdown = String.raw`---
title: "Six Knots"
subtitle: "A pocket book for the boat and the garden"
author: "Ellen Marsh"
---

# Six Knots {style="cover" strap="A pocket book for the boat and the garden"}

# Before you tie {kicker="Introduction"}

A knot is a way of making a rope hold onto something: another rope, a post, a ring, itself. There are thousands of them, and most of us need six. The six in this book will moor a boat, hang a hammock, tie down a load, join two lines and make a loop that will not slip, and every one of them can be untied again, which is half the point of a good knot.

Learn them with a piece of soft rope about an arm's length long, and tie each one ten times before you move on. Then tie it with your eyes shut. A knot you have to think about will fail you on a cold, wet evening, when the boat is moving and the rope is stiff.

Each knot has a standing part, the long end that takes the load, and a working end, the short end you tie with. When the instructions say *over* and *under*, they mean the working end passing over or under the standing part.

# The reef knot {kicker="Knot 1 · Joining"}

The reef knot joins two ends of the same rope around a bundle: a parcel, a sail rolled on its boom, a bandage. Left over right and under, then right over left and under. If the two ends lie on the same side of the knot, you have tied it correctly; if they lie on opposite sides, you have a granny knot, which jams or slips.

Never use a reef knot to join two different ropes that will take a load. It is a binding knot, not a bend, and under strain it can capsize into two loops that slide apart.

# The bowline {kicker="Knot 2 · Loops"}

The bowline makes a loop at the end of a rope that will neither slip nor jam. Make a small loop in the standing part, with the working end on top. Bring the end up through the loop, round behind the standing part, and back down through the loop. The old way to remember it: the rabbit comes out of the hole, goes round the tree, and goes back down the hole.

A bowline holds a mooring line on a post, a rope round a person's chest in a rescue, and the corner of a tarpaulin in a gale. However hard it has been pulled, you can break it open again by pushing the collar forward.

# The clove hitch {kicker="Knot 3 · Hitches"}

The clove hitch ties a rope to a post or a rail in a moment. Take two turns round the post, crossing the second over the first, and tuck the end under the second turn. It is quick to tie and quick to adjust, which makes it the knot for fenders on a boat and for the first turn of a lashing.

It can work loose when the pull comes and goes, so on anything that matters add two half hitches round the standing part, or use a round turn instead.

# The figure-eight {kicker="Knot 4 · Stoppers"}

The figure-eight is a stopper: it sits at the end of a rope and stops it running out through a block, a cleat or a hole. Make a loop, pass the end round behind the standing part and down through the loop, and pull it snug. It looks like the number it is named after.

Climbers tie it doubled, as a loop, and every sailor ties it in the ends of the sheets. Unlike a simple overhand knot, it can always be untied, even after a long day under strain.

# The sheet bend {kicker="Knot 5 · Joining"}

The sheet bend joins two ropes, even ropes of different thickness. Make a bight in the thicker rope. Pass the thinner end up through the bight, round behind both its parts, and under itself. For a wet or slippery line, take the end round twice: that is a double sheet bend, and it will not shake loose.

It is the knot for lengthening a line that turned out too short, and for mending a net, where it is tied thousands of times.

# The round turn {kicker="Knot 6 · Hitches"}

A round turn and two half hitches will hold almost anything to a ring or a post, and it can be untied while the rope is under load. Take the working end twice round the post, then make two half hitches round the standing part, each one the same way.

The round turn takes the strain, and the hitches only keep it in place. That is why it is the safest knot for tying a boat to a ring on the quay at the end of the day, and the last one in this book.

# Looking after rope {kicker="Afterword"}

Rope lasts for years if you treat it well. Rinse salt out of it in fresh water after a season on the boat, and dry it loosely coiled in the shade, never in a tight hank in the sun. Sunlight weakens synthetic fibre faster than any load.

Seal the ends before they fray: whip them with waxed twine, or melt a synthetic end in a flame and roll it smooth between wet fingers. A rope that has been crushed, cut or burned along its length belongs in the garden, tying up beans, and no longer on the boat.

Coil it the same way every time, and it will come off the coil without kinks when you need it in a hurry.

:::paragraphs{style="colophon"}
Set in Source Serif 4 and Outfit (SIL Open Font License) · Text: original, CC BY 4.0.
:::

# Six Knots {style="back" strap="Tie them ten times each, then once more in the dark."}
`; // content.<lang>.md, inlined by the Cookbook

// ─── 3 · Fonts ──────────────────────────────────────────────────────────────
const FONTS = { 'Source Serif 4': ['400', '400i', '700'], Outfit: ['400', '600', '700'] };

// ─── 4 · Build & show ───────────────────────────────────────────────────────
await loadFonts(FONTS, markdown);
const doc = await buildWithFonts(() => buildDocument({ markdown }, config()), markdown);
showPages(doc, { title: 'Six Knots · the Folio settings bench' });
// cover: 'pages' needs an even count (gotcha: folio-cover-pages-even); the back's break
// gives it one.
if (doc.pages.length % 2) console.warn(`${doc.pages.length} pages: the back cover is missing`);


// #region answer: one viewer, restyled in place by setAppearance on every change
const book = createFolioFromDocument(document.getElementById('folio'), doc, {
  // The look starts from doc.config.folio; setAppearance replaces it on every change.
  appearance: { textureBaseUrl: 'https://postext.dev/folio/textures' },
  onChange: ({ pages }) => kitStatus(`${doc.pages.length} pages · open at `
    + pages.map((i) => i + 1).join('–')),
});
function update() {
  const folio = folioOf();
  // Only the appearance changes: the pages keep their paintings, nothing is laid out again.
  book.setAppearance({ folio });
  show('grammage-out', `${folio.paper.grammage} g/m²`);
  show('intensity-out', folio.lighting.intensity.toFixed(2));
  show('tilt-out', `${folio.tilt}°`);
  document.getElementById('folio-json').textContent = `folio: ${JSON.stringify(folio, null, 2)}`;
}
form.addEventListener('input', update);
// A stock sets its own weight: picking one moves the weight slider to the stock's.
const WEIGHTS = { uncoated: 90, bookWove: 80, coatedMatte: 115, coatedSilk: 115,
  coatedGloss: 115, bible: 40, newsprint: 48, cardStock: 250 };
form.elements['paper.type'].addEventListener('change', (event) => {
  form.elements['paper.grammage'].value = WEIGHTS[event.target.value];
  update();
});
document.getElementById('reset-view').addEventListener('click', () => book.resetView());
update();
// #endregion

// ─── 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 v1 ── the same in every recipe · postext.dev/cookbook ────────
// Postext measures text with the faces the browser has loaded, and caches the
// widths, so every face must be ready before the first build. Faces come from
// Fontsource: the same static files the PDF embeds, so screen and PDF agree.

/** faces = { 'Family Name': ['400', '400i', '700'] }. `text` is the sample:
 *  letters beyond Latin-1 (č, ł, ő…) also load the latin-ext files. With
 *  `optional`, a face Fontsource does not ship is skipped instead of failing.
 *  Resolves to the number of faces added. */
async function loadFonts(faces, text = '', { optional = false } = {}) {
  kitStatus('Loading fonts…');
  const ranges = {
    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',
  };
  const subsets = /[Ā-˿Ḁ-ỿ]/.test(text) ? ['latin', 'latin-ext'] : ['latin'];
  const jobs = [];
  let added = 0;
  for (const [family, specs] of Object.entries(faces)) {
    const id = fontsourceId(family);
    const meta = optional ? await fontsourceMeta(family) : null;
    for (const spec of new Set(specs)) {
      const weight = parseInt(spec, 10);
      const style = spec.endsWith('i') ? 'italic' : 'normal';
      if (hasFace(family, weight, style)) continue;
      if (optional && !(meta?.weights.includes(weight) && meta.styles.includes(style))) continue;
      for (const subset of subsets) {
        const url = `https://cdn.jsdelivr.net/npm/@fontsource/${id}@5/files/${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().then((ready) => { document.fonts.add(ready); added++; }, () => {
          if (subset === 'latin' && !optional) throw new Error(`Fontsource has no ${family} ${weight} ${style}`);
        }));
      }
    }
  }
  await Promise.all(jobs).catch((error) => { kitFail(error); throw error; });
  return added;
}

/** Runs `build` (a buildDocument or buildBundle call) and checks the faces
 *  the pages use. A regular face missing from FONTS is loaded with a warning;
 *  bold and italic variants are loaded when the family ships them. Then the
 *  measurement caches are cleared and the build runs again. */
async function buildWithFonts(build, text = '') {
  const tried = new Set();
  for (let round = 0; round < 3; round++) {
    kitStatus('Laying out…');
    await new Promise(requestAnimationFrame);          // let the status paint first
    const result = await Promise.resolve().then(build).catch((error) => { kitFail(error); throw error; });
    const wanted = { base: {}, variants: {} };
    for (const { font, base } of [result].flat().flatMap(fontStringsOf)) {
      const { family, weight, style } = parseFont(font);
      const key = `${family}|${weight}|${style}`;
      if (tried.has(key) || hasFace(family, weight, style)) continue;
      tried.add(key);
      (wanted[base ? 'base' : 'variants'][family] ??= []).push(`${weight}${style === 'italic' ? 'i' : ''}`);
    }
    if (Object.keys(wanted.base).length) {
      console.warn(`[cookbook] FONTS does not list ${JSON.stringify(wanted.base)}: loading them.`);
    }
    const added = await loadFonts(wanted.base, text) + await loadFonts(wanted.variants, text, { optional: true });
    if (added === 0) return result;
    clearMeasurementCache();
  }
  throw new Error('The fonts did not settle after three builds.');
}

/** Every font string of the layout. `base` marks a block's own face; its
 *  bold, italic and bold-italic variants are listed whether or not used. */
function fontStringsOf(doc) {
  const found = new Map();
  const walk = (node) => {
    if (!node || typeof node !== 'object') return;
    if (Array.isArray(node)) { node.forEach(walk); return; }
    for (const [key, value] of Object.entries(node)) {
      if (typeof value === 'string' && /fontString$/i.test(key)) {
        found.set(value, found.get(value) || key === 'fontString');
      } else if (value && typeof value === 'object') walk(value);
    }
  };
  walk(doc.pages);
  walk(doc.blocks);
  return [...found].map(([font, base]) => ({ font, base }));
}

/** '700 37.5px Open Sans' / 'italic 400 13px "Source Serif 4"' → { family, weight, style }.
 *  A string with no weight ('95.8px Young Serif', from a design text) is 400. */
function parseFont(font) {
  const m = /^(?:(italic|oblique)\s+)?(?:small-caps\s+)?(?:(\d+|bold|normal)\s+)?[\d.]+px\s+(.+)$/.exec(font.trim());
  if (!m) throw new Error(`Unexpected font string: ${font}`);
  const weight = m[2] === 'bold' ? 700 : !m[2] || m[2] === 'normal' ? 400 : Number(m[2]);
  return { family: m[3].replace(/^["']|["']$/g, ''), weight, style: m[1] ? 'italic' : 'normal' };
}

/** True when a loaded FontFace covers exactly this family, weight and style
 *  (document.fonts.check() is also true for families nobody declared). */
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;
}

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

/** The weights and styles a family ships ({ weights: [400, 700], styles: ['normal', 'italic'] }), or null. */
function fontsourceMeta(family) {
  fontsourceMeta.cache ??= new Map();
  const id = fontsourceId(family);
  if (!fontsourceMeta.cache.has(id)) {
    fontsourceMeta.cache.set(id, fetch(`https://api.fontsource.org/v1/fonts/${id}`)
      .then((res) => (res.ok ? res.json() : null), () => null));
  }
  return fontsourceMeta.cache.get(id);
}

// ─── Kit · viewer v1 ── the same in every recipe · postext.dev/cookbook ───────
/** Shows the pages as facing spreads on a dark desk: the first page is a
 *  recto on its own, then verso | recto pairs, as in a bound book. Pages
 *  are painted when they scroll near the screen. */
function showPages(docs, { title, width = 460 } = {}) {
  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, { 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 ───────────────────────────────────────────────────────────────────────
```

## تنويعات

### ابدأ من غلاف مقوّى في علبة من القماش

غيّر القيم الافتراضية للنموذج في `index.html`؛ ويتبعها المستند وSandbox.

```diff
-        <option value="hardcover">Hardcover</option><option value="paperback" selected>Paperback</option>
+        <option value="hardcover" selected>Hardcover</option><option value="paperback">Paperback</option>
```

### كتاب واحد، ومظهره في الإعدادات

تكتب وصفة [كتاب على المكتب](https://postext.dev/ar/cookbook/folio-book-on-a-desk.md) الإعدادات نفسها مرة واحدة في `config.folio`، بلا نموذج، وتضع [كرّاسة عيّنات الورق](https://postext.dev/ar/cookbook/paper-swatch-book.md) ورقًا مختلفًا على كل ورقة.

## أخطاء شائعة

- **يأخذ عارض Folio مقاس حاويته.** يضع createFolioFromDocument الكتاب داخل العنصر الذي تعطيه إياه، مع الأزرار وعدد الصفحات في هوامشه. والعنصر الذي لا ارتفاع له (div فارغ في التدفق العادي) لا يعرض شيئًا: أعطه ارتفاعًا في CSS.
- **Cover: 'pages' يحتاج إلى عدد زوجي من الصفحات للغلاف الخلفي.** حين يُضبط binding.cover على 'pages' تنقلب الصفحة الأولى غلافًا أماميًا، ولا تنقلب الصفحة الأخيرة غلافًا خلفيًا إلا إذا وقعت في صفحة زوجية. فالعدد الفردي من الصفحات يترك الكتاب بغلاف أمامي بلا غلاف خلفي: أكمله إلى عدد زوجي أو احتفظ بالغلاف الصلب.
- **حمّل كل أوجه الخط قبل الإخراج.** يقيس الإخراج النص بأوجه الخط التي حمّلها المتصفح ويخزّن العروض مؤقتًا، فالوجه الذي يصل بعد البناء الأول يترك فواصل أسطر خاطئة وملف PDF لم يعد يطابق الشاشة. حمّل كل وزن وكل نمط أولًا، واستدعِ clearMeasurementCache() قبل إعادة البناء إذا تأخر وصول أحدها.
- **يُخزَّن الإعداد مؤقتًا بحسب هويته: ابنِ كائنًا جديدًا.** يخزّن المحرّك الإعدادات المحسوبة مؤقتًا بحسب هوية الكائن، فتعديل الإعداد في مكانه ثم البناء مجددًا يعيد استخدام النتيجة القديمة. ابنِ كائنًا جديدًا في كل بناء، ولهذا يكون إعداد الوصفة دالة مصنِّعة: config().
- **أي كائن headings يُلغي فاصل الصفحة قبل H1.** ينتقل H1 افتراضيًا إلى صفحة فردية (always-odd)، لكن تمرير أي كائن headings يعيد ضبط هذا الافتراض، فتتوالى الفصول دون فاصل ولا يفعل span: 'page' شيئًا. أعد كتابة headings.levels[0].breakBefore: { enabled: true, parity } في كل إعداد.

## الحقوق

- الوصفة: Ignacio Ferro ([@drnachio](https://github.com/drnachio))
- الخطوط: Source Serif 4 (OFL-1.1), Outfit (OFL-1.1)
- الشيفرة: MIT · محتوى المثال: CC-BY-4.0

## وصفات ذات صلة

- [رقم 100 · كتاب مُخرَج على المكتب، بالأبعاد الثلاثة](https://postext.dev/ar/cookbook/folio-book-on-a-desk.md): تفتح الدالة createFolioFromDocument من الحزمة postext-folio فصلًا مُخرَجًا ككتاب مجلَّد بالقماش على مكتب من خشب الجوز، بمظهر يحدده config.folio. · المستوى 2 (متوسط) · الأدب القصصي والمسرح والنثر الأدبي
- [رقم 101 · كتاب عيّنات، كل ورقة فيه على ورقها الخاص](https://postext.dev/ar/cookbook/paper-swatch-book.md): كل ورقة من كتاب عيّنات لتاجر ورق تقع داخل سياج :::paper، ويرسمها postext-folio بلون ذلك الورق ووزنه وسطحه وصلابته. · المستوى 2 (متوسط) · الكتالوجات
- [رقم 040 · خطوط العلامة في الإخراج وملف PDF والحزمة](https://postext.dev/ar/cookbook/brand-fonts-identity-manual.md): دليل هوية لمترو متخيَّل منضَّد بملفات خطوط العلامة نفسها، تُنزَّل مرة واحدة ويعيد استخدامها الإخراج ومزوّد خطوط PDF وحزمة .postext. · المستوى 3 (متقدم) · الأدلة والمراجع
