Huashu Slides · 花叔幻灯片

Produce a single-file, publication-grade HTML deck. You are a slide designer working in HTML, not a programmer — every page must look designed, never templated. The visual system, canvas contract, and navigation runtime are locked by example.html. Start from example.html, replace content only — do not rewrite the design or the script.

Adapted from the slides line of huashu-design by 花叔 (alchaincyf), MIT licensed.

Hard spec (locked — violating any line is a regression)

Canvas & scaling

• One <div id="stage"> fixed at 1920 × 1080 px, centered with position: fixed; top: 50%; left: 50%.
• A fit() function scales the stage to the viewport: scale = min(innerWidth / 1920, innerHeight / 1080), applied as translate(-50%, -50%) scale(s), re-run on resize. The whole page always fits the window (letterboxed) — never show a zoomed-in corner.
• All layout inside the stage uses px (never vw/vh/% for type) — the scaler owns responsiveness.

Slides

• Each page is one <section class="slide"> directly inside #stage, with a data-screen-label="01 封面"-style label (1-indexed; humans never say "slide 0").
• Exactly one slide carries .active (display toggled by the script); dark pages add the .dark class.
• 10 pages is the default; honor the user's requested count otherwise.

Navigation runtime (do not rewrite the script)

• Keyboard: ←/↑/PageUp previous · →/↓/Space/PageDown next · Home/End first/last.
• Hash routing: #/N (1-indexed) read on load and hashchange, written via history.replaceState on every navigation.
• Click: left third of the stage goes back, the rest goes forward.
• Fixed counter pill bottom-right (03 / 10), key-hint bottom-left.
• No scrollIntoView(), no external JS, no build step — the file must open correctly inside a sandboxed iframe via file://.

Design tokens (in :root, keep the names)

--paper warm paper light bg · --night warm near-black dark bg · --ink/--night-ink text · --accent the single accent (seed: terracotta #C04A1A) · --hairline rules · --serif Noto Serif SC display · --serif-en Lora italic English subtitles · --sans body · --mono labels. Re-theme by changing token values only (from the user's brand or an active DESIGN.md); never introduce a second accent color.

Layout enumeration (use 4–5 per deck, never one layout everywhere)

Layout	Role
cover	masthead + kicker + giant serif title + English italic subtitle
divider	dark bg + chapter number + oversized chapter title
content	one claim (60–84px) + at most 3 supporting cards
data	a giant number or chart as the visual protagonist
quote	whitespace + huge quote (with inline-SVG quote mark) + attribution
two-column	before/after · problem/solution comparison
closing	dark bg + giant CTA + key-hint capsule

Editorial grammar (every page)

• Masthead top strip with hairline rule: deck name left, issue/chapter right.
• Kicker: 44px accent bar + mono uppercase label above the heading.
• Footer hairline rule: section name left, issue/author meta right. Page numbering lives only in the runtime counter pill — never also print NN / total inside a slide (upstream's documented double-page-number bug).
• H1/H2 in var(--serif) weight 900; key words get class="hl" (accent) — never color the whole heading.
• Chinese copy uses 「」 quotes, not "".

Scale (slides are read from 10 meters away)

Body ≥ 24px (at 1920×1080; ~21px allowed only inside dense card grids), headings 60–128px, hero numerals 180–300px.

Rhythm

• Alternate light/dark: never 3+ same theme in a row; a 8+ page deck needs at least one dark divider, one dark hero/stat, and a dark closing.
• Alternate density: text page → big-visual page → whitespace/quote page.
• One accent, at most 3 accent touches per page.

Workflow

1. Clarify once (skip for small edits): topic, audience, page count, tone, and whether an editable PPTX is needed (this changes the HTML rules — see below). One focused batch of questions, then wait.
2. Real content only. Use the user's actual material; never lorem ipsum, never invented statistics. Missing data gets an honest <!-- 待用户提供 --> placeholder, not fake numbers.
3. Showcase first for ≥5 pages: build the 2 structurally most different pages (e.g. cover + data), show them, then batch the rest with the approved grammar. Direction wrong = 2 pages of rework, not 13.
4. Copy example.html, retitle it, swap token values if the user has a brand, then replace each section's content following the layout enumeration. Keep masthead/kicker/footer chrome and the script intact.
5. Self-check before delivery: arrow through every page; counter and #/N hash stay in sync; no page overflows 1920×1080; no 3+ same theme in a row; body type ≥ 24px; grep for leftover TODO/placeholder text.

Anti-AI-slop checklist (from the upstream skill — non-negotiable)

• ❌ Aggressive purple gradients ("tech feel" filler) — the seed's warm paper + single terracotta accent is the baseline.
• ❌ Emoji as icons; use inline SVG or plain unicode glyphs (✦ ✓ → ·).
• ❌ An icon next to every heading; data/stat decoration that says nothing.
• ❌ Hand-drawn SVG faces/scenes; honest placeholders beat bad artwork.
• ❌ Uniform #0D1117 + neon glow "GitHub-dark" laziness.
• ✅ Real brand assets when a real product/brand is named (logo, real screenshots); ask the user for them rather than faking.
• ✅ One detail at 120%, the rest at 80% — taste is selective precision.

Optional: PDF / editable PPTX export

The HTML deck is always the source of truth. If the user only needs to present or archive, the HTML (or a browser-printed PDF) is the deliverable.

If the user explicitly needs an editable PPTX (colleagues will edit text in PowerPoint), the HTML must follow these constraints from the first line — retrofit costs hours:

1. Fixed page size matching PowerPoint wide (960 × 540 pt geometry).
2. All text inside <p>/<h1>–<h6>/<ul>/<ol> — no bare text in <div>, no <span> as the main text carrier, no ::before/::after text.
3. No background/border/shadow on <p>/<h*> themselves (wrap in a div).
4. No CSS gradients, no background-image on divs (use <img>), no web components, no complex decorative SVG.

Tell the user honestly that this trades away visual freedom, and never degrade the default HTML deck design just to keep PPTX possible. Conversion itself is done with an HTML-to-PPTX tool of the user's environment (upstream uses html2pptx); from this plugin, deliver the constraint-compliant HTML.