# 写在原稿用紙上的小说，一格一字

> 《坊っちゃん》的开头写在400字的原稿用紙上：画出20 × 20的方格，每个字或符号占一格，不能居行首的、。悬挂在格下。

- HTML版本: https://postext.dev/zh/cookbook/genko-yoshi-manuscript
- 食谱 No. 120 · 页面与网格 · 难度 2 (中级) · 输出: Canvas, PDF
- 体裁: 单页与零散印品
- 需要 postext ≥ 1.16.1, postext-pdf ≥ 1.16.1 · 已用 1.16.1, postext-pdf 1.16.1 测试，日期 2026-10-05
- 页面: [1](https://postext.dev/cookbook/genko-yoshi-manuscript/en/p01.webp?v=a964e91c), [2](https://postext.dev/cookbook/genko-yoshi-manuscript/en/p02.webp?v=a964e91c), [3](https://postext.dev/cookbook/genko-yoshi-manuscript/en/p03.webp?v=a964e91c)
- PDF: https://postext.dev/cookbook/genko-yoshi-manuscript/en/genko-yoshi-manuscript.pdf?v=a964e91c
- 在沙盒中打开: https://postext.dev/zh/sandbox#recipe=genko-yoshi-manuscript&lang=en (.postext: https://postext.dev/cookbook/genko-yoshi-manuscript/en/genko-yoshi-manuscript.postext)
- 最后更新: 2026-10-05
- 其他语言: [en](https://postext.dev/en/cookbook/genko-yoshi-manuscript.md), [es](https://postext.dev/es/cookbook/genko-yoshi-manuscript.md), [ca](https://postext.dev/ca/cookbook/genko-yoshi-manuscript.md), [ja](https://postext.dev/ja/cookbook/genko-yoshi-manuscript.md), [ar](https://postext.dev/ar/cookbook/genko-yoshi-manuscript.md)

## 简单来说

日本的稿纸每个字都有一个方格。这一页把一部名作的开头几行抄在稿纸上，标题、作者名和每个标点都放在日本学校规定的位置。

## 成品一览

三张日文稿纸（原稿用紙，genkō yōshi），400格的那种，上面抄着夏目漱石《坊っちゃん》的头三段，就像作家或学生那样写：20行，每行20格，从右起自上而下读，用Klee One，一款以钢笔书写为基础的字体。标题在第一行，从第三格起；作者名在第二行，在底端上方一格结束；每段从一个空格之后开始。每个字、小写假名和符号都占一个自己的方格，本该落在行首的、或。写在上一行最后一格之下。红褐色的框、稿纸编号和纸上印的规格20×20构成这张纸。按字数计量的中文页面见[Nº 082](https://postext.dev/zh/cookbook/chinese-official-document.md)。

**这份食谱回答的问题:**

- 怎样把日文排在20格×20行的稿纸上，每格一个字？
- 为什么日文的小假名、ー和闭括号不能出现在行首？怎样选择规则的严格程度？

## 简短回答

```js
// script.js, 行 38–50
// The grid makes the type area 20 characters of 20 pt down and 20 lines of 27 pt across, and
// show draws its squares. The marks are set full width with nothing squeezed, so each
// character, mark or bracket fills its own square, as on manuscript paper (原稿用紙).
const cjk = {
  grid: { enabled: true, charsPerLine: N, linesPerPage: N, show: true },
  compressAdjacent: false, // 。」 take two squares, not one and a half
  trimLineStart: false, // a bracket at the head of a line keeps its square
  // The manuscript rule: a small kana or ー may head a line (each has its own square), but
  // never 、。 or a closing bracket: such a mark is written in the last square of the line
  // before, hanging below it here, and no line is squeezed to take it in.
  lineBreak: 'ja-loose',
  hangingPunctuation: 'force',
};
```

## 用料

**讲解**

- [字符网格](https://postext.dev/zh/docs/configuration.md#字格): 按中文习惯指定版心，即每行字数乘以每页行数（cjk.grid）：行长是整数个em，页边距相应加大，使版心居中，网格还可以在屏幕上显示出来。
- [日文禁则处理](https://postext.dev/zh/docs/japanese-layout.md#断行禁则): 日文可以在任意两个字之间断行，JLReq禁止的位置除外：行首不能是闭括号、、。、小假名（ぁ ッ ャ）、ー、叠字符（々 ゝ）或〜，行末不能是开括号，――和……不能拆开。标记为ja的文档采用最严格的一级；允许小假名和ー出现在行首的书，可以用cjk.lineBreak选'ja-strict'或'ja-loose'。
- [日文标点间距（約物）](https://postext.dev/zh/docs/japanese-layout.md#约物标点间距): 日文标点按全角排，并按JLReq的规则挤压：相邻的两个标点共用、。「」的半个字空白，行末的标点最先让出空白，・：；两侧各留四分之一字，段落中的？！后面空一个字，段首的开括号缩进半个字。cjk.spaceAfterQuestion和cjk.paragraphStartBracket可以改变后两条；行末悬挂、。（ぶら下げ）由cjk.hangingPunctuation控制。

**还用到**

- [竖排](https://postext.dev/zh/docs/configuration.md#竖排)
- [右翻书](https://postext.dev/zh/docs/configuration.md#装订)
- [占行标题（行取り）](https://postext.dev/zh/docs/japanese-layout.md#标题与文字块)
- [假名、汉字与罗马字](https://postext.dev/zh/docs/japanese-layout.md#汉字假名与罗马字)
- [中日韩字体](https://postext.dev/zh/docs/configuration.md#中文日文和韩文字体)
- [导入青空文库文本](https://postext.dev/zh/docs/japanese-layout.md#青空文库源文本)
- [段落样式](https://postext.dev/zh/docs/configuration.md#段落样式)
- [页面设计中的文字、线条和框](https://postext.dev/zh/docs/configuration.md#页眉与页脚)
- [书眉与页码](https://postext.dev/zh/docs/configuration.md#页眉与页脚)
- [纸张颜色](https://postext.dev/zh/docs/configuration.md#页面)
- [语义调色板](https://postext.dev/zh/docs/configuration.md#调色板)
- [导出PDF](https://postext.dev/zh/docs/configuration.md#生成pdf)
- [中文断行](https://postext.dev/zh/docs/configuration.md#东亚排版)
- [中文标点宽度](https://postext.dev/zh/docs/configuration.md#标点宽度)
- [各栏齐底](https://postext.dev/zh/docs/configuration.md#各栏齐底)
- [标题属性](https://postext.dev/zh/docs/document-format.md#标题属性)
- [按页面角色显示书眉](https://postext.dev/zh/docs/configuration.md#文本元素)
- [嵌入PDF的字体](https://postext.dev/zh/docs/configuration.md#为什么需要字体提供函数)

**配置一览**

- [`bodyText`](https://postext.dev/zh/docs/configuration.md#正文), [`cjk`](https://postext.dev/zh/docs/configuration.md#东亚排版), [`colorPalette`](https://postext.dev/zh/docs/configuration.md#调色板), [`footer`](https://postext.dev/zh/docs/configuration.md#页眉与页脚), [`header`](https://postext.dev/zh/docs/configuration.md#页眉与页脚), [`headings`](https://postext.dev/zh/docs/configuration.md#标题), [`layout`](https://postext.dev/zh/docs/configuration.md#版式), [`locale`](https://postext.dev/zh/docs/configuration.md#断词), [`page`](https://postext.dev/zh/docs/configuration.md#页面), [`paragraphStyles`](https://postext.dev/zh/docs/configuration.md#段落样式)

**API**

- [`buildDocument`](https://postext.dev/zh/docs/configuration.md#构建文档), [`clearMeasurementCache`](https://postext.dev/zh/docs/configuration.md#测量缓存), [`decompressWoff2`](https://postext.dev/zh/docs/configuration.md#浏览器字体提供函数fontsource--woff2), `loadVerticalAlternates`, [`renderPageToCanvas`](https://postext.dev/zh/docs/configuration.md#把页面渲染为位图), [`renderToPdf`](https://postext.dev/zh/docs/configuration.md#生成pdf)

**字体**

- Klee One (OFL-1.1), Noto Sans JP (OFL-1.1)

## 做法

### 1 · 画出方格，每个符号占一整格

代码见上文的[简短回答](#简短回答)。[字符网格](/zh/docs/configuration#字格)把版心设为竖向20个20 pt（7.1 mm）的字、横向20行、行距27 pt（9.5 mm），`show: true`用它自己的浅灰色把方格画出来：屏幕上总会画，PDF里只有在`renderToPdf`收到`characterGrid: true`时才画（在书里网格是校样用的辅助线，所以PDF默认不画）；两行之间2.5 mm的窄条，是写作者添读音、改字的地方。日文的标点一半是字形，一半是半个em的空白；印刷的书在两个标点相遇或括号位于行首时会吃掉这些空白。稿纸上每个符号保住自己的格子，所以`compressAdjacent: false`把。」排在两格里，`trimLineStart: false`让行首的括号占一整格（[东亚排版](/zh/docs/configuration#东亚排版)）。

### 2 · 遵守稿纸的行规

稿纸有自己的禁则。小写假名和ー可以放在行首，各占一格，`ja-loose`允许这样做。本该落在行首的、或。写在上一行的最后一格里，与那里的字挤在一起，或者写在它的正下方；`hangingPunctuation: 'force'`把它悬挂在第二十格之下，任何一行都不挤压。如果用日文的默认值`'allow'`，引擎会先把行内的一个、挤到半格，把这个符号收进本行，印刷的书这样做，稿纸从不这样做：那一行其余的字会往上错半格，与网格线错开。

### 3 · 把标题和姓名写在规定的位置

```js
// script.js, 行 54–61
// The title on the first line, two squares down; the writer's name on the second, ending a
// square above the foot (地から一字上げ), a blank square between family and given names.
// lineSpan: 1 keeps the title on one line of the grid, in the text's own size and face.
const title = { level: 1, fontFamily: PEN, fontSize: pt(CELL), fontWeight: 400, lineSpan: 1,
  indent: em(2), breakBefore: { enabled: true, parity: 'any' } }; // gotcha: headings-drop-h1-break
const paragraphStyles = [
  { id: 'name', textAlign: 'end', endIndent: em(1), firstLineIndent: em(0) },
];
```

标题是一个与正文字号、字体相同的标题，所以它像其他行一样填格子：`lineSpan: 1`让它保持在网格的一行里，`indent: em(2)`在它上方留两个空格（[按级别覆盖](/zh/docs/configuration#按级别覆盖)）。姓名是一个段落，设`textAlign: 'end'`和`endIndent: em(1)`，让它在底端上方一格结束；姓与名之间的空格在Markdown里写作全角空格：`夏目　漱石`。正文从第三行开始，`firstLineIndent: em(1)`让每段空一格开始。

### 4 · 在方格周围印出稿纸

```js
// script.js, 行 65–89
// The header is drawn on the sheet itself, not in the turned frame of the text: x runs right
// from the left edge, y down from the top. The frame stands 1.5 mm off the squares and 8 mm
// below them, where a 、 or 。 that cannot head a line is written outside the last square.
const box = (id, inset, foot, thickness) => ({ kind: 'box', id, pages: 'all',
  placement: { anchor: { to: 'page', edge: 'top-left' },
    offset: { x: mm(MARGIN.side - inset), y: mm(MARGIN.top - inset) },
    size: { width: mm(GRID.across + 2 * inset), height: mm(GRID.down + inset + foot) } },
  style: { borderColor: col('ruling'), borderWidth: pt(thickness) } });
const FOOT = MARGIN.top + GRID.down + 8; // mm: the frame's foot
const below = (id, content, x, extra) => ({ kind: 'text', id, content, pages: 'all',
  placement: { anchor: { to: 'page', edge: 'top-left' }, offset: { x: mm(x), y: mm(FOOT + 3) } },
  ...extra });
const header = { elements: [
  box('outer', 2.6, 9.1, 1.2), box('inner', 1.5, 8, 0.4),
  // The sheet number, as a writer numbers the sheets; the paper's printed label.
  below('sheet', '（{pageNumber}）', MARGIN.side, { fontFamily: PEN, fontSize: pt(9),
    color: col('muted') }),
  below('label', '20×20', MARGIN.side + GRID.across - 12, { fontFamily: 'Noto Sans JP',
    fontSize: pt(7), letterSpacing: pt(0.5), color: col('ruling') }),
] };
const footer = { elements: [{ kind: 'text', id: 'colophon', content: '{attr.colophon}',
  pages: 'opener', fontFamily: 'Noto Sans JP', fontSize: pt(6), lineHeight: 1.4,
  color: col('muted'), overflow: 'wrap', align: 'center',
  placement: { anchor: { to: 'page', edge: 'bottom' }, offset: { y: mm(-5) },
    size: { width: mm(120) } } }] };
```

页眉的元素画在纸面上：在竖排页面上，`x`从左上角向右、`y`向下，这与标题的设计不同，后者在文字的旋转坐标系中排。双线框在三边离方格1.5 mm，在下方离方格8 mm，悬挂的符号就落在那里。`GRID`和`MARGIN`用页边距所依据的同一组数字来放置它；交给页面的页边距要小半毫米，因为网格把它们当作最小值，正好相等时可能取整成19行。

### 5 · 用钢笔字体来排

```js
// script.js, 行 142–147
// Klee One draws the strokes of a pen, with the Japanese forms of the kanji; its vertical
// forms put 、。 in the upper right of their square and turn ー and the brackets.
const colophon = markdown.match(/colophon="([^"]*)"/)[1];
await loadFonts(FONTS, markdown); // the Latin files: the colophon
await loadCjkFonts({ [PEN]: ['400'] }, `${markdown}（）一二三四五六七八九十`, { vertical: true });
await loadCjkFonts({ 'Noto Sans JP': ['400'] }, `20×20${colophon}`);
```

Klee One以钢笔书写为基础，汉字保留日本的字形，所以稿纸读起来像手写的，又没有扫描件的那种参差。它的竖排字形把、。放在格子的右上方，并把ー和括号转过来，写作者也正是把它们写在那里。和Fontsource上的所有日文字体一样，它拆成大约120个文件，`loadCjkFonts`只取文本用到的那些（[中文、日文和韩文字体](/zh/docs/configuration#中文日文和韩文字体)）。

## 完整食谱

一个文件，由食谱文件夹合成，示例文本和排版食谱的公共工具包都已内联；它自己排出页面。要运行它，把它放进空白页面的`<script type="module">`，或粘贴到新建CodePen的JS面板里（设为模块）。它从esm.sh导入postext，不需要安装或构建。

- 食谱文件夹: https://github.com/drnachio/postext/tree/main/cookbook/genko-yoshi-manuscript

### script.js

```js
// ═══ Postext Cookbook · Nº 120 · A story on genkō yōshi, one character to a square ═══
// https://postext.dev/en/cookbook/genko-yoshi-manuscript
// Code: MIT · Text: 夏目漱石『坊っちゃん』, Aozora Bunko 752 (public domain) · Pictures: none
// Fonts: Klee One, Noto Sans JP (SIL OFL 1.1) · Needs postext ≥ 1.16.1
import {
  buildDocument, renderPageToCanvas, clearMeasurementCache, loadVerticalAlternates,
} from 'https://esm.sh/postext';
import { renderToPdf, decompressWoff2 } from 'https://esm.sh/postext-pdf';

const LANG = 'en'; // @lang: the language of the colophon; the manuscript is Japanese in both
const RECIPE = 'genko-yoshi-manuscript';

// ─── 1 · Design ─────────────────────────────────────────────────────────────
// #region palette: blue-black ink on a sheet ruled in red-brown
const palette = {
  ink: '#1f2a44', // the pen: a blue-black
  ruling: '#b0573f', // the sheet's printed frame, its label
  muted: '#7b6f66', // the sheet number
  paper: '#fdfaf3',
};
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: 'defaults', value: { hex: palette.ruling, model: 'hex' } },
];
// #endregion
const PEN = 'Klee One'; // a pen-written kaisho with Japanese forms
const [CELL, PITCH, N] = [20, 27, 20]; // pt: a 7 mm square, a 2.5 mm strip beside each line
const PT = 25.4 / 72; // mm in a point
const SHEET = { w: 230, h: 200 }; // mm
const GRID = { down: N * CELL * PT, across: N * PITCH * PT }; // 141.1 × 190.5 mm
const MARGIN = { top: 32, side: (SHEET.w - GRID.across) / 2 }; // mm
// The margins handed to the page are a hair smaller: the grid takes them as minimums and
// grows them back, where an exact fit could round to 19 lines.
const SLACK = 0.5; // mm

// #region answer: 20 squares down 20 lines, the squares drawn, every character in one
// The grid makes the type area 20 characters of 20 pt down and 20 lines of 27 pt across, and
// show draws its squares. The marks are set full width with nothing squeezed, so each
// character, mark or bracket fills its own square, as on manuscript paper (原稿用紙).
const cjk = {
  grid: { enabled: true, charsPerLine: N, linesPerPage: N, show: true },
  compressAdjacent: false, // 。」 take two squares, not one and a half
  trimLineStart: false, // a bracket at the head of a line keeps its square
  // The manuscript rule: a small kana or ー may head a line (each has its own square), but
  // never 、。 or a closing bracket: such a mark is written in the last square of the line
  // before, hanging below it here, and no line is squeezed to take it in.
  lineBreak: 'ja-loose',
  hangingPunctuation: 'force',
};
// #endregion

// #region heading: the title two squares down, the name a square above the foot
// The title on the first line, two squares down; the writer's name on the second, ending a
// square above the foot (地から一字上げ), a blank square between family and given names.
// lineSpan: 1 keeps the title on one line of the grid, in the text's own size and face.
const title = { level: 1, fontFamily: PEN, fontSize: pt(CELL), fontWeight: 400, lineSpan: 1,
  indent: em(2), breakBefore: { enabled: true, parity: 'any' } }; // gotcha: headings-drop-h1-break
const paragraphStyles = [
  { id: 'name', textAlign: 'end', endIndent: em(1), firstLineIndent: em(0) },
];
// #endregion

// #region sheet: the printed frame round the squares, the sheet number and the paper's label
// The header is drawn on the sheet itself, not in the turned frame of the text: x runs right
// from the left edge, y down from the top. The frame stands 1.5 mm off the squares and 8 mm
// below them, where a 、 or 。 that cannot head a line is written outside the last square.
const box = (id, inset, foot, thickness) => ({ kind: 'box', id, pages: 'all',
  placement: { anchor: { to: 'page', edge: 'top-left' },
    offset: { x: mm(MARGIN.side - inset), y: mm(MARGIN.top - inset) },
    size: { width: mm(GRID.across + 2 * inset), height: mm(GRID.down + inset + foot) } },
  style: { borderColor: col('ruling'), borderWidth: pt(thickness) } });
const FOOT = MARGIN.top + GRID.down + 8; // mm: the frame's foot
const below = (id, content, x, extra) => ({ kind: 'text', id, content, pages: 'all',
  placement: { anchor: { to: 'page', edge: 'top-left' }, offset: { x: mm(x), y: mm(FOOT + 3) } },
  ...extra });
const header = { elements: [
  box('outer', 2.6, 9.1, 1.2), box('inner', 1.5, 8, 0.4),
  // The sheet number, as a writer numbers the sheets; the paper's printed label.
  below('sheet', '（{pageNumber}）', MARGIN.side, { fontFamily: PEN, fontSize: pt(9),
    color: col('muted') }),
  below('label', '20×20', MARGIN.side + GRID.across - 12, { fontFamily: 'Noto Sans JP',
    fontSize: pt(7), letterSpacing: pt(0.5), color: col('ruling') }),
] };
const footer = { elements: [{ kind: 'text', id: 'colophon', content: '{attr.colophon}',
  pages: 'opener', fontFamily: 'Noto Sans JP', fontSize: pt(6), lineHeight: 1.4,
  color: col('muted'), overflow: 'wrap', align: 'center',
  placement: { anchor: { to: 'page', edge: 'bottom' }, offset: { y: mm(-5) },
    size: { width: mm(120) } } }] };
// #endregion

const config = () => ({ // a factory: the engine caches resolved configs per object
  locale: 'ja', // written out, never LANG (gotcha: ja-locale-tag)
  colorPalette,
  page: {
    sizePreset: 'custom', width: mm(SHEET.w), height: mm(SHEET.h), dpi: 150,
    backgroundColor: col('paper'),
    margins: { top: mm(MARGIN.top - SLACK), bottom: mm(SHEET.h - MARGIN.top - GRID.down - SLACK),
      left: mm(MARGIN.side - SLACK), right: mm(MARGIN.side - SLACK) },
  },
  layout: { layoutType: 'single', writingMode: 'vertical-rl' },
  cjk,
  bodyText: {
    fontFamily: PEN, fontSize: pt(CELL), lineHeight: pt(PITCH), color: col('ink'),
    boldColor: col('ink'), italicColor: col('ink'), referenceColor: col('ink'),
    textAlign: 'left', firstLineIndent: em(1), indentAfterHeading: true, // a blank square
  },
  headings: { fontFamily: PEN, color: col('ink'), levels: [title],
    balancing: { enabled: false } }, // gotcha: cjk-grid-balancing
  paragraphStyles,
  header,
  footer,
});

// ─── 2 · Content ────────────────────────────────────────────────────────────
const markdown = String.raw`---
title: "坊っちゃん"
author: "夏目漱石"
---

# 坊っちゃん {colophon="Natsume Sōseki, 坊っちゃん (Botchan, 1906), its first three paragraphs, copied out on 400-character manuscript paper. Text: Aozora Bunko 752, public domain. Set in Klee One and Noto Sans JP (SIL OFL)."}

:::paragraphs{style="name"}
夏目　漱石
:::

親譲りの無鉄砲で小供の時から損ばかりしている。小学校に居る時分学校の二階から飛び降りて一週間ほど腰を抜かした事がある。なぜそんな無闇をしたと聞く人があるかも知れぬ。別段深い理由でもない。新築の二階から首を出していたら、同級生の一人が冗談に、いくら威張っても、そこから飛び降りる事は出来まい。弱虫やーい。と囃したからである。小使に負ぶさって帰って来た時、おやじが大きな眼をして二階ぐらいから飛び降りて腰を抜かす奴があるかと云ったから、この次は抜かさずに飛んで見せますと答えた。

親類のものから西洋製のナイフを貰って奇麗な刃を日に翳して、友達に見せていたら、一人が光る事は光るが切れそうもないと云った。切れぬ事があるか、何でも切ってみせると受け合った。そんなら君の指を切ってみろと注文したから、何だ指ぐらいこの通りだと右の手の親指の甲をはすに切り込んだ。幸ナイフが小さいのと、親指の骨が堅かったので、今だに親指は手に付いている。しかし創痕は死ぬまで消えぬ。

庭を東へ二十歩に行き尽すと、南上がりにいささかばかりの菜園があって、真中に栗の木が一本立っている。これは命より大事な栗だ。実の熟する時分は起き抜けに背戸を出て落ちた奴を拾ってきて、学校で食う。菜園の西側が山城屋という質屋の庭続きで、この質屋に勘太郎という十三四の倅が居た。勘太郎は無論弱虫である。弱虫の癖に四つ目垣を乗りこえて、栗を盗みにくる。ある日の夕方折戸の蔭に隠れて、とうとう勘太郎を捕まえてやった。その時勘太郎は逃げ路を失って、一生懸命に飛びかかってきた。向うは二つばかり年上である。弱虫だが力は強い。鉢の開いた頭を、こっちの胸へ宛ててぐいぐい押した拍子に、勘太郎の頭がすべって、おれの袷の袖の中にはいった。邪魔になって手が使えぬから、無暗に手を振ったら、袖の中にある勘太郎の頭が、右左へぐらぐら靡いた。しまいに苦しがって袖の中から、おれの二の腕へ食い付いた。痛かったから勘太郎を垣根へ押しつけておいて、足搦をかけて向うへ倒してやった。山城屋の地面は菜園より六尺がた低い。勘太郎は四つ目垣を半分崩して、自分の領分へ真逆様に落ちて、ぐうと云った。勘太郎が落ちるときに、おれの袷の片袖がもげて、急に手が自由になった。その晩母が山城屋に詫びに行ったついでに袷の片袖も取り返して来た。
`; // content.<lang>.md: the same Japanese text in both

// ─── 3 · Fonts ──────────────────────────────────────────────────────────────
const FONTS = {
  'Klee One': ['400'], // the manuscript
  'Noto Sans JP': ['400'], // the sheet's printed label and the colophon
};

// ─── 4 · Build & show ───────────────────────────────────────────────────────
// #region pen: a pen-written face, loaded with the characters the sheets set
// Klee One draws the strokes of a pen, with the Japanese forms of the kanji; its vertical
// forms put 、。 in the upper right of their square and turn ー and the brackets.
const colophon = markdown.match(/colophon="([^"]*)"/)[1];
await loadFonts(FONTS, markdown); // the Latin files: the colophon
await loadCjkFonts({ [PEN]: ['400'] }, `${markdown}（）一二三四五六七八九十`, { vertical: true });
await loadCjkFonts({ 'Noto Sans JP': ['400'] }, `20×20${colophon}`);
// #endregion
const doc = await buildWithFonts(() => buildDocument({ markdown }, config()), markdown);
showBook(doc, { title: t({ en: 'A story on genkō yōshi, one character to a square',
  es: 'Un relato en genkō yōshi, un carácter por casilla' }) });
// The PDF draws the squares only when asked: a grid is a screen aid in a book, the page here.
offerPdf(() => renderToPdf(doc, { fontProvider: cjkPdfProvider, characterGrid: true }),
  `${RECIPE}.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 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 · pdf v1 ── the same in every recipe that exports a PDF ──────────────
/** postext-pdf embeds TrueType bytes. Fetch the Fontsource file the screen
 *  used, snapping to a weight the family ships and falling back to upright
 *  when it has no italic: the PDF asks for every face a block could use. */
async function fontsourceProvider(family, weight, style) {
  const id = fontsourceId(family);
  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 && !meta.styles.includes('italic') ? 'normal' : style;
  const res = await fetch(`https://cdn.jsdelivr.net/npm/@fontsource/${id}@5/files/${id}-latin-${w}-${s}.woff2`);
  if (!res.ok) throw new Error(`Fontsource has no ${family} ${w} ${s} (${res.status})`);
  return decompressWoff2(new Uint8Array(await res.arrayBuffer()));
}

/** A "Build the PDF" button in the bar. Once built: "Open the PDF" (a new
 *  tab, since CodePen's preview frame cannot show 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 v1 ── 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 = `https://cdn.jsdelivr.net/npm/@fontsource/${id}@5/${weight}${style === 'italic' ? '-italic' : ''}.css`;
  if (!cjkSlices.cache.has(css)) {
    cjkSlices.cache.set(css, fetch(css)
      .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], css).href, range, ranges };
      }).reverse()));
  }
  return cjkSlices.cache.get(css);
}

/** The file of `slices` that holds code point `cp`, if any. */
function cjkSliceFor(slices, cp) {
  return slices.find((slice) => slice.ranges.some(([lo, hi]) => cp >= lo && cp <= hi));
}

/** 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 buildWithFonts 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 that
 *  hold the characters its pages set (`request.codePoints`); 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.filter((slice) => picked.has(slice)).map(async (slice) => {
    const res = await fetch(slice.url);
    if (!res.ok) throw new Error(`Fontsource file ${slice.url} (${res.status})`);
    return decompressWoff2(new Uint8Array(await res.arrayBuffer()));
  }));
}

/** 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. Latin comes first: postext-pdf draws a character from the first
 *  file that has it, as the browser takes a character both files hold from
 *  latin. 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 = `https://cdn.jsdelivr.net/npm/@fontsource/${id}@5/files/${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)]);
  return ext ? [latin, ext] : 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 ───────────────────────────────────────────────────────────────────────
```

## 变化

### 用同样的方格检查一本书的网格

`show: true`适用于任何字符网格：在[Nº 117](https://postext.dev/zh/cookbook/bunko-novel-furigana.md)的文库本上，它在正文上画出38 × 15的方格，可以很快查看每一行是否守在网格上，每个标题是否占满三行。

```diff
-  grid: { enabled: true, charsPerLine: CHARS, linesPerPage: LINES },
+  grid: { enabled: true, charsPerLine: CHARS, linesPerPage: LINES, show: true },
```

### 像印刷页那样挤压符号

用日文的默认值，稿纸读起来就像在方格纸上打字排出的一本书：本该落在行首的、靠挤压另一个、收进行内，那一行其余的字偏离网格半格。

```diff
-  hangingPunctuation: 'force',
+  hangingPunctuation: 'allow',
```

## 常见问题

- **日文文本标记为'ja'，不要用zh-Hans或LANG.** 食谱的版本是en和es，但日文示例在两个版本里都是日文：`locale: LANG`会把它标记为英文或西班牙文，中文标记则会按中文规则排它（开明式标点、小假名可以出现在行首、图代替図、PDF中用中文字形）。写'ja'：它选用日本地区（JLReq断行和标点、芝麻着重号、振假名的分布、図和表标签），并关闭断词。lint会让带假名却标记为zh或ko的文本失败。
- **传入任何headings对象都会关掉H1换页.** 默认情况下，H1换页到右页（always-odd），但只要传入headings对象，这个默认值就会被重置，于是各章接排，span: 'page'也不起作用。在每份配置中重新写明headings.levels[0].breakBefore: { enabled: true, parity }。
- **中文字体通过cjk块分片加载.** Fontsource把一个中文、日文或韩文字体家族按每个字重约一百个文件提供，每个文件覆盖一段字符范围。loadFonts只获取latin文件，所以屏幕上的汉字来自系统字体，测量不准；fontsourceProvider交给PDF的也是这个latin文件，汉字印出来是空框。列出kit中的cjk块，在loadFonts之后调用loadCjkFonts(FONTS, markdown)（书中用到几种CJK字体时，每种字体调用一次，并传入它所排的文字），并给renderToPdf传fontProvider: cjkPdfProvider：两者都会取用包含文中字符的那些文件。
- **在字格网格上关闭各栏齐底.** 页面提前结束时（例如标题要与正文同栏，在页底留下空行），各栏齐底会在标题上方增加网格行，或把一个段落排松一行，把页面填满。中文行排松后字会散开（在GB/T 9704页面上为0.13 em，远超balancing.maxTracking），于是字离开网格的列，标题也离开它们所在的行。以格计量的页面应当让它提前结束：设置headings.balancing: { enabled: false }。
- **竖排页面有两套坐标：转过来的正文和纸面.** vertical-rl文档把正文当作一张顺时针转了九十度的横排页面来排，标题的设计（advancedDesign.slot中的元素）也放在这个转过的坐标系里：x沿页面向下，y从右边缘向左横跨页面，元素的宽度沿页面向下量。页眉和页脚的元素仍在纸面上：x从左边缘向右，y从顶端向下。所以页眉里画的框和标题设计里放的书名，偏移量是在不同的轴上量的。竖排扉页上的元素要锚定到`page`，从页面边缘量起：锚定到`container`时，页脚的元素会偏离版心中线几毫米（约5 mm）。

## 致谢

- 食谱: Ignacio Ferro ([@drnachio](https://github.com/drnachio))
- 文字: 夏目漱石『坊っちゃん』 (Botchan, 1906), the first three paragraphs, without the readings; Aozora Bunko card 752, from 「ちくま日本文学全集　夏目漱石」 (Chikuma Shobō, 1992), input 真先芳秋, proofreading 柳沢成雄, converted with aozora.py: Natsume Sōseki; Aozora Bunko volunteers ([来源](https://www.aozora.gr.jp/cards/000148/card752.html)), 公有领域
- 字体: Klee One (OFL-1.1), Noto Sans JP (OFL-1.1)
- 代码: MIT · 示例内容: CC-BY-4.0

## 相关食谱

- [No. 082 · 按GB/T 9704排一份党政机关公文](https://postext.dev/zh/cookbook/chinese-official-document.md): 一份按国家标准排在A4纸上的四页通知：三号字28 × 22字的版心、红色版头、一、（一）1.（1）四级标题、附件，以及“— 1 —”式页码。 · 难度 2 (中级) · 报告
- [No. 117 · 竖排并标振假名的日文文库本小说](https://postext.dev/zh/cookbook/bunko-novel-furigana.md): 漱石《夢十夜》排在A6文库本页面上：每行38字、共15行，从右向左读，生僻汉字旁标读音，每夜的标题占三行。 · 难度 2 (中级) · 小说、戏剧与文学散文
- [No. 085 · 刻本书叶：四周双边、界行与版心](https://postext.dev/zh/cookbook/woodblock-leaf.md): 照刻本的样子排朱熹《论语集注》：一叶占一个跨页，四周双边，行间有界行，折缝处是版心。 · 难度 2 (中级) · 教科书