论文后置部分：附录、术语表和索引

// ═══ Postext Cookbook · Nº 031 · Thesis back matter: appendix, glossary and index ═══
// https://postext.dev/en/cookbook/thesis-back-matter
// Code: MIT · Text: original (CC BY 4.0) · Pictures: none
// Fonts: Libertinus Serif, Serif Display and Sans (SIL OFL 1.1) · Needs postext ≥ 1.7.0
import {
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} from 'https://esm.sh/postext';
import { renderToPdf, decompressWoff2 } from 'https://esm.sh/postext-pdf';

const LANG = 'en'; // @lang: the language of the sample document ('en')
const RECIPE = 'thesis-back-matter';

// ─── 1 · Design ─────────────────────────────────────────────────────────────
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// ─── 2 · Content ────────────────────────────────────────────────────────────
const markdown = String.raw`---
Markdown样例 · 126行 · content.en.md
title: "Reading on Screens and Paper"
subtitle: "A Mixed-Methods Study of Comprehension, Confidence and Navigation"
author: "Ines Varley"
---

# Conclusion

This thesis set out to test whether it matters if a long text:index{term="texts, length of"} is read on paper or on a screen. Chapters 3 to 5 reported a within-subjects:index{term="within-subjects design"} experiment with forty-eight :index[undergraduates] and :index[interviews] with sixteen of them, combined in the :index[convergent design] described by Creswell:index{term="Creswell, John W."} and Plano Clark:index{term="Plano Clark, Vicki L."} (2018). This chapter brings the two strands together and sets out what they mean for :index[teaching] and for the :index[design of reading software].

## What the study found

:ref{id="findings" style="full"} summarises the results.:index{term="comprehension"} On :index[literal]{term="comprehension!literal"} questions, answerable from a single sentence, the medium made no difference. On :index[inferential]{term="comprehension!inferential"} questions, which required connecting ideas across paragraphs, paper readers scored higher. The difference points the same way as the :index[meta-analyses] of Delgado:index{term="Delgado, Pablo"} et al. (2018) and Clinton:index{term="Clinton, Virginia"} (2019), which found the :index[paper advantage] in :index[expository]{term="expository text"} rather than :index[narrative]{term="narrative text"} texts.

Calibration:index{term="calibration"} showed the larger difference. Screen readers:index{term="calibration!on screen"} predicted:index{term="confidence!judgements of"} higher scores than paper readers and obtained lower ones, so the gap between :index[confidence] and :index[accuracy]:index{term="calibration!bias in"} was nearly three times as wide. The result repeats the :index[overconfidence] that Ackerman:index{term="Ackerman, Rakefet"} and Goldsmith:index{term="Goldsmith, Morris"} (2011) found in students who read on screen and set their own study time.:index{term="self-regulated study"} Such readers stop once they judge a text understood, so overconfidence cuts their study short.

Paper readers also turned back:index{term="look-backs"} almost twice as often as screen readers scrolled back:index{term="scrolling"}, most often just before an inferential question.:index{term="comprehension!inferential"} In the interviews:index{term="interviews"}, eleven of the sixteen :index[participants] remembered:index{term="memory"} where on a page:index{term="spatial memory"} an idea had been (“top left, next to the diagram”), and three gave up looking for a passage on the :index[tablet] because “it could have been anywhere”. Liu:index{term="Liu, Ziming"} (2005) described a drift towards :index[browsing] and :index[keyword spotting] on screen; these readers went through the whole text but had fewer :index[landmarks] to return to.

## Implications for teaching and design

For short texts and factual questions, screens serve as well as paper.:index{term="teaching"} For long expository:index{term="expository text"} texts that students must understand:index{term="comprehension"} rather than search, paper remains the safer choice.:index{term="paper advantage"} Where it is not available, students should test their understanding instead of trusting their sense of it: in the :index[pilot sessions], a short :index[self-test] after reading halved the overconfidence:index{term="overconfidence"} on screen.:index{term="calibration!on screen"}

Readers also used the fixed position of text on a page as a map,:index{term="landmarks"} one of the uses of paper that Sellen:index{term="Sellen, Abigail J."} and Harper:index{term="Harper, Richard H. R."} (2002) observed in offices.:index{term="offices, paper in"} Reading applications:index{term="design of reading software"} that keep a stable page and show the reader’s place in the whole text may restore some of that map.

## Limitations and further work

The participants:index{term="participants"} were students at one university:index{term="university, single"} who read English fluently,:index{term="limitations"} and the medium matters more for some readers, texts and tasks than it does for others (Singer:index{term="Singer, Lauren M."} & Alexander:index{term="Alexander, Patricia A."}, 2017). The texts were expository and about 1,800 words long,:index{term="texts, length of"} and the screen condition used a single tablet.:index{term="tablet"} A :index[replication] with a larger sample, several devices and the eye-movement:index{term="eye movements"} recording reviewed by Rayner:index{term="Rayner, Keith"} (1998) would show where on the page the two media part company.

Huey:index{term="Huey, Edmund Burke"} (1908) thought that a complete analysis of what we do when we read would be almost the acme of a psychologist’s achievements. The experiments reported here add a small part to that analysis; the replication proposed above could measure how far readers rely on the position of a passage on the page when they look back.

# Interview guide {style="appendix" letter="A"}

The interviews:index{term="interviews"} took place within a week of each participant’s:index{term="participants"} second session. They were audio-recorded,:index{term="interviews!recording of"} transcribed:index{term="transcription"} in full and analysed thematically:index{term="thematic analysis"} following Braun:index{term="Braun, Virginia"} and Clarke:index{term="Clarke, Victoria"} (2006); :ref{id="session-plan" style="full"} gives their timing:index{term="interviews!timing of"}: a free recall:index{term="recall"} of the two study texts, the questions below and a short debriefing.:index{term="debriefing"} The questions were asked in this order,:index{term="interviews!questions asked"} and a prompt:index{term="interviews!prompts in"} only when the participant had not already covered its point.

1. Tell me about the last long text:index{term="texts, length of"} you read for a course.:index{term="courses, reading for"}
   - Where did you read it, and on paper or on a screen?
2. Which of the texts in this study do you remember:index{term="memory"} best, and why?
3. When you wanted to check an earlier passage, what did you do?:index{term="look-backs"}
   - How did you know where to look?
4. How sure were you of your answers?:index{term="confidence"} What made you more or less sure?
5. Did reading on the tablet:index{term="tablet"} feel different from reading on paper?
6. Some students say they read more carefully on paper. Do you?
7. What would the ideal way to read a long text for study be like?:index{term="design of reading software"}

# Glossary {style="glossary" note="Words in italics are defined under entries of their own."}

:::paragraphs{style="term"}
**calibration**:index{term="calibration" main} The agreement between a reader’s confidence in having understood a text and the accuracy of that understanding, measured here as the difference between predicted and actual scores.

**comprehension, inferential**:index{term="comprehension!inferential" main} Understanding that requires the reader to connect information from different parts of a text or to add knowledge the text does not state.

**comprehension, literal**:index{term="comprehension!literal" main} Understanding of what a single sentence or passage states directly.

**confidence judgement**:index{term="confidence!judgements of" main} A reader’s estimate, made after reading and before seeing the questions, of how many answers will be correct.

**convergent design**:index{term="convergent design" main} A mixed-methods design in which quantitative and qualitative data are collected in the same period, analysed separately and then compared.

**expository text**:index{term="expository text" main} A text written to explain or inform, such as a textbook chapter or a report, as opposed to a narrative text.

**fixation**:index{term="fixation" main} A pause of the eyes, typically about a quarter of a second, during which the reader takes in text; fixations alternate with *saccades*.

**look-back**:index{term="look-backs" main} Any return to an earlier part of a text during reading: turning back a page, scrolling up or following a link to a previous section.

**metacomprehension**:index{term="metacomprehension" main} A reader’s knowledge and monitoring of their own understanding of a text; *calibration* is one of its measures.

**navigation**:index{term="navigation" main} The movements a reader makes through a text as a whole, as distinct from the movements of the eyes along a line.

**overconfidence**:index{term="overconfidence" main} Positive *calibration* bias: predicting a higher score than the one actually obtained.

**saccade**:index{term="saccade" main} A rapid movement of the eyes from one *fixation* to the next, during which little or no text is taken in.

**screen inferiority effect**:index{term="screen inferiority effect" main} The finding that comprehension of the same text is lower on screen than on paper, most consistently for *expository texts* read under time pressure.

**self-regulated study**:index{term="self-regulated study" main} Reading in which the reader, not the experimenter, decides how long to spend on a text.

**spatial memory for text**:index{term="spatial memory" main} Memory of where on a page or in a document a piece of information appeared, used as a cue for *look-backs*.

**thematic analysis**:index{term="thematic analysis" main} A method for identifying, analysing and reporting patterns of meaning across qualitative data such as interview transcripts.

**within-subjects design**:index{term="within-subjects design" main} An experimental design in which every participant takes part in every condition, here reading on both paper and screen.
:::

# References {style="references" note="Every work cited in the thesis, set in APA style (7th edition)."}

:::paragraphs{style="reference"}
Ackerman, R., & Goldsmith, M. (2011). Metacognitive regulation of text learning: On screen versus on paper. *Journal of Experimental Psychology: Applied, 17*(1), 18–32.

Baron, N. S. (2015). *Words onscreen: The fate of reading in a digital world.* Oxford University Press.

Braun, V., & Clarke, V. (2006). Using thematic analysis in psychology. *Qualitative Research in Psychology, 3*(2), 77–101.

Clinton, V. (2019). Reading from paper compared to screens: A systematic review and meta-analysis. *Journal of Research in Reading, 42*(2), 288–325.

Creswell, J. W., & Plano Clark, V. L. (2018). *Designing and conducting mixed methods research* (3rd ed.). SAGE.

Delgado, P., Vargas, C., Ackerman, R., & Salmerón, L. (2018). Don’t throw away your printed books: A meta-analysis on the effects of reading media on reading comprehension. *Educational Research Review, 25*, 23–38.

Dillon, A. (1992). Reading from paper versus screens: A critical review of the empirical literature. *Ergonomics, 35*(10), 1297–1326.

Huey, E. B. (1908). *The psychology and pedagogy of reading.* Macmillan.

Liu, Z. (2005). Reading behavior in the digital environment: Changes in reading behavior over the past ten years. *Journal of Documentation, 61*(6), 700–712.

Mangen, A., Walgermo, B. R., & Brønnick, K. (2013). Reading linear texts on paper versus computer screen: Effects on reading comprehension. *International Journal of Educational Research, 58*, 61–68.

Noyes, J. M., & Garland, K. J. (2008). Computer- vs. paper-based tasks: Are they equivalent? *Ergonomics, 51*(9), 1352–1375.

Paterson, D. G., & Tinker, M. A. (1940). *How to make type readable.* Harper & Brothers.

Rayner, K. (1998). Eye movements in reading and information processing: 20 years of research. *Psychological Bulletin, 124*(3), 372–422.

Sellen, A. J., & Harper, R. H. R. (2002). *The myth of the paperless office.* MIT Press.

Singer, L. M., & Alexander, P. A. (2017). Reading on paper and digitally: What the past decades of empirical research reveal. *Review of Educational Research, 87*(6), 1007–1041.

Tinker, M. A. (1963). *Legibility of print.* Iowa State University Press.

Wolf, M. (2018). *Reader, come home: The reading brain in a digital world.* Harper.
:::

# Index {style="index" note="Bold numbers refer to the definitions in the glossary."}

:::index

:::callout{type="colophon"}
Set in Libertinus Serif, Libertinus Serif Display and Libertinus Sans (SIL Open Font License). Text: original, CC BY 4.0. The thesis, its author, its participants and its results are fictional; the works in the references are real.
:::
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// ─── 4 · Build & show ───────────────────────────────────────────────────────
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工具包 · core, fonts, viewer, pdf：每道食谱都相同 · 275行
// ─── Kit ── helpers shared by every Cookbook recipe · postext.dev/cookbook ─────

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// 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 ───────────────────────────────────────────────────────────────────────