Front-matter reference

Every key a deck’s front matter can carry. To learn how front matter works, and which settings most decks want, start with Deck settings.

This page is generated from the engine’s table of front-matter keys (lib/core/deck-settings.js), the same table the Studio editor completes from and lint:deck checks against. A key Lattice does not read draws an unknown-key warning, and a value outside a key’s list draws unknown-<key>, so finsh: halo or size: huge is caught instead of rendering the default. Marp’s own keys (marp:, headingDivider:, author: and the like) are accepted and ignored, and are not listed here. The groups match the sections under Settings → Deck in the Studio, in the same order.

For an editor outside the Studio, npm run build writes the same table as a JSON Schema, dist/schemas/front-matter.schema.json. Point your editor’s YAML support at it to complete keys and values as you type.

One slide can differ from the deck through the per-slide form a row names. Where it reads <value>, put the value there: the deck’s spectrum: off is spectrum-off on one slide. Not every value has a class (there is no spectrum-on, because on is what a slide gets with no class), and a key whose row names no per-slide form, such as theme: or size:, applies to the whole deck only.

The LFM specification defines a portable subset of these keys, for tools other than Lattice. This page is what Lattice itself reads.

Look

Theme, canvas, size and the overall hand of the deck.

Key	What it does	Values	Default
theme:	Deck theme (palette) — e.g. indaco, cuoio. Studio: Settings → Deck → Look → Theme.	a theme name, e.g. indaco, cuoio	indaco
size:	Slide size — hd (16:9), standard, square, 4k, or a portrait format. Studio: Settings → Deck → Look → Size.	hd · HD · 4K · 4k · standard · 16:9 · mobile-landscape · square · 1:1 · portrait · 4:5 · story · reel · 9:16 · mobile	hd
preset:	A named look that sets the backdrop, alignment and accent registers at once — an explicit key (finish:, rule:, …) overrides it. Studio: Settings → Deck → Look → Preset (also in Basic).	classic · editorial · brand · minimal	classic
color-mode:	The mode the deck opens in. Studio: Settings → Deck → Look → Color mode. One slide: _class: dark · color-light · color-system · print.	light · dark · system · inherited · print	the theme’s own
mode:	Rendering mode. Studio: Settings → Deck → Look → Mode. One slide: _class: sketch.	boardroom · sketch · sketch-clean	boardroom
finish:	Finish backdrop — e.g. atrium, halo, gallery. Studio: Settings → Deck → Look → Finish. One slide: _class: finish-<name>.	none · atrium · meridian · strata · halo · ledger · nimbus · loom · savile · gallery	none
finish-override:	Override the applied finish — a nested map (backdrop: { strength, clearance }, wash, …). Applies to: Studio only (written by Fabricate).	a nested map of finish layers	none
backdrop:	Restrain any finish — e.g. `backdrop: 40 clear`. Studio: Settings → Deck → Look → Backdrop strength · Backdrop mask. One slide: _class: backdrop-<value>.	20 · 40 · 60 · 80 · full · clear · open · spot-tl · spot-t · spot-tr · spot-l · spot-c · spot-r · spot-bl · spot-b · spot-br	the finish's own
tag:	Style every card tag — e.g. `tag: plain band center`. Studio: Settings → Deck → Look → Card tags (Tag color · size · placement · text). One slide: _class: tag-<value>.	color · plain · none · small · regular · large · corner · foot · notch · band · inline · start · center · end	the component's own
image-card:	Style the text card on every image slide that floats its words over the photo (spotlight, statement) — e.g. `image-card: top-right soft sm`, or `image-card: bottom band` for a full-width strip along the bottom edge. Applies to: image slides only. Studio: Settings → Deck → Image (Placement · Backing · Ink · Size · Density · Shape). One slide: _class: at-<corner> · card-<backing> · card-o<level> · ink-<value> · card-<size> · compact · card-regular · band · card-float.	bottom-left · bottom · bottom-right · center · top-left · top · top-right · solid · soft · sheer · clear · 5% · 10% · 15% · 20% · 25% · 30% · 35% · 40% · 45% · 50% · 60% · 65% · 70% · 75% · 85% · 90% · 95% · light · dark · md · sm · lg · regular · compact · float · band	bottom-left solid md regular
lift:	Card lift — the "Struck" shadow on card surfaces. Studio: Settings → Deck → Look → Card lift. One slide: _class: lifted · flat.	on · off	off
chart-finish:	How every chart spends its color. Applies to: every chart's marks and key. Studio: Settings → Deck → Look → Chart finish. One slide: _class: chart-finish-<value> · chart-finish-off.	off · pigment · etching · tone	off
venue:	Where the deck is seen — sets the type size for the back row. laptop (default) · huddle (4–6 people) · conference (10–30) · hall (50+). Applies to: type size, label size and lint budgets. Studio: Settings → Deck → Look → Venue. One slide: _class: venue-<value>.	laptop · huddle · conference · hall	laptop
cards:	Where a card row puts spare height — omit it and the component decides. Studio: Settings → Deck → Look → Frame and fit → Card rows. One slide: _class: cards-<value>.	center · stretch · top · spread	each component decides
corners:	Slide surface corners. Studio: Settings → Deck → Look → Frame and fit → Corners. One slide: _class: corners-<value>.	square · rounded	square
claim:	How much frame the content sits inside. Studio: Settings → Deck → Look → Frame and fit → Claim. One slide: _class: claim-<value>.	framed · quiet · hero · bleed	framed
fit:	What the engine may do to make a slide fit — replaces guards:. Studio: Settings → Deck → Look → Frame and fit → Fit. One slide: _class: fit-<value>.	report · heal · trim	heal
code:	Default options for every code block — e.g. numbers, wrap. A fence's own record wins. Applies to: every code fence.	code-record options, e.g. numbers, wrap	none
avatar:	The deck's default for inline avatars. One slide: _class: avatar-<value>.	circle · rounded · square · framed · bare	circle framed
callout:	The deck's default for inline callouts. One slide: _class: callout-<value>.	on · off	on
icon:	The deck's default for inline icons. One slide: _class: icon-<value>.	framed · bare · pigment · etching · tone · square · rounded	framed pigment square
spark:	The deck's default for inline sparks. One slide: _class: spark-<value>.	framed · bare · pigment · etching · tone · square · rounded	framed pigment square

Chrome

The furniture on every slide: running header and footer, page numbers, logo.

Key	What it does	Values	Default
header:	Running header text on every slide. Studio: Settings → Deck → Chrome → Header. One slide: <!-- _header: … -->.	any text	none
footer:	Running footer text on every slide. Studio: Settings → Deck → Chrome → Footer. One slide: <!-- _footer: … -->.	any text	none
paginate:	Page numbers — on unless false (also no, off, 0). One slide opts out with the no-pagination class, back in with with-pagination. Studio: Settings → Deck → Chrome → Page numbers. One slide: _class: … no-pagination.	true · false	true
meta:	The masthead bay’s meta line — a date, a document number, a review stage. Studio: Settings → Deck → Chrome → Meta line.	any text; | starts a new line	none
logo:	Deck logo — a path beside the deck or a full URL, drawn into the masthead. Studio: Settings → Deck → Chrome → Logo.	a path beside the deck, a URL, or lattice	none
logo-finish:	Style the logo on one line, up to one word per axis: placement (top-left / top-center / top-right / bottom-left / bottom-center / bottom-right — e.g. `logo-finish: bottom-center accent-ink`. `_class: no-logo` hides it on one slide. Studio: Settings → Deck → Chrome → Logo.	top-right · top-left · top-center · bottom-left · bottom-center · bottom-right · auto · accent · ink · muted · canvas · inverse · brand · accent-ink · accent-canvas · ink-canvas · no-plate · plate · md · sm · lg · all · title	top-right auto md all

General

What the deck is called, what language it is in, and how its source is read.

Key	What it does	Values	Default
title:	Deck name — used in the switcher, in Share, and as the export filename. Defaults to the cover heading. Applies to: HTML title, Studio switcher, export filename. Studio: Settings → Deck → General → Deck name.	any text	the first heading
lang:	Document language — overrides the workspace default (e.g. en-US). Drives <html lang> + read-aloud. Applies to: page language and read-aloud voice. Studio: Settings → Deck → General → Language.	a language tag, e.g. en-US	en
ai-lang:	AI-output language — what the AI writes in, if it should differ from the document language. Defaults to lang. Applies to: Studio only. Studio: Settings → Deck → General → AI writes in.	a language tag	follows lang
split:	How the body divides into slides — headings (default) or rule (--- only). Studio: Settings → Deck → General → New slide on.	rule · headings	headings
inline-code:	Inline code pills and marks. Studio: Settings → Deck → General → Inline pills and marks. One slide: _class: inline-code-literal.	rich · literal	rich
glossary:	Auto-glossary — append a reference slide built from the acronyms: definitions. Studio: Settings → Deck → General → Auto-glossary.	auto · off	off
class:	Default _class applied to every slide (a modifier — a component name is ignored). Studio: Settings → Deck → General → Default slide class. One slide: _class:.	modifier classes, space-separated	none
plugins:	Plugins the deck needs loaded — a list of plugin names. It only adds: a renderer that loads more by default still does.	anima · avatars · callout · chart-family · code · function-plot · icons · legend · math · mermaid · meta · pills · sparks	the built-in set

Accent

The small decorations: brand bar, heading rule, kicker mark, stamps.

Key	What it does	Values	Default
spectrum:	Brand bar. Studio: Settings → Deck → Accent → Brand bar. One slide: _class: spectrum-<value>.	on · solid · duo · mono · off	on
spectrum-edge:	Which edge the brand bar sits on. Studio: Settings → Deck → Accent → Bar placement. One slide: _class: spectrum-edge-<value>.	top · left · right · bottom · off	top
spectrum-card:	Card rail style. Studio: Settings → Deck → Accent → Card rail. One slide: _class: spectrum-card (auto) · spectrum-card-<value>.	off · auto · solid · duo · mono · rainbow	off
spectrum-card-edge:	Card rail placement. Studio: Settings → Deck → Accent → Card rail placement. One slide: _class: spectrum-card-edge-<value>.	left · top · right · bottom	left
spectrum-trim:	Flow the spectrum onto structural accents (table rails, code strips, hr). Studio: Settings → Deck → Accent → Structural trim. One slide: _class: spectrum-trim · spectrum-trim-restrained.	off · restrained · on	off
rule:	Heading underline. Studio: Settings → Deck → Accent → Heading rule. One slide: _class: rule-<value>.	auto · full · short · accent · none	auto
eyebrow:	The mark on the mono-caps kicker. Studio: Settings → Deck → Accent → Eyebrow. One slide: _class: eyebrow-<value>.	plain · dot · bar · arrow · underline	plain
headline:	Framing-text alignment. Studio: Settings → Deck → Accent → Headline alignment. One slide: _class: head-<value>.	auto · left · center · right	auto
stamp:	Deck-wide state-badge shape — e.g. tab, notch, seal, pill. Studio: Settings → Deck → Accent → Badges → Stamp shape. One slide: _class: stamp-<value>.	tab · notch · bracket · seal · pill · ribbon · flag · underline · dot · mark · veil · bar · pin	tab
tone:	Deck-wide review-tone shape. Studio: Settings → Deck → Accent → Badges → Tone shape. One slide: _class: tone-<value>.	rail · edge · glow	rail

Motion

How charts move on live surfaces. A PDF is always still.

Key	What it does	Values	Default
motion:	Chart motion on the live surfaces — reaches the preview, Present and the exported player (see player-motion); the PDF stays still. Applies to: preview, Present and the exported player. Studio: Settings → Deck → Motion → Play. One slide: _class: motion-on · motion-off.	on · off	off
motion-style:	How a chart moves. Studio: Settings → Deck → Motion → Style. One slide: _class: motion-<value>.	build · together · rise	build
motion-speed:	How fast the build runs. Studio: Settings → Deck → Motion → Speed. One slide: _class: motion-<value>.	auto · slow · normal · fast	auto
player-motion:	off ships still charts in the exported offline player while motion stays on for presenting. Omit it to follow motion. Applies to: exported player only. Studio: Settings → Deck → Motion → In the exported player.	off	follows motion

Speech

How the deck is read aloud.

Key	What it does	Values	Default
pace:	Presentation rhythm. Applies to: self-presenting playback. Studio: Settings → Deck → Speech → Pace.	brisk · natural · deliberate	natural
delivery:	How much the narrated Guide gestures. Applies to: the Present Guide while narration plays.	restrained · expressive · somber	restrained
lexicon:	Read-aloud pronunciations — a nested map of token → spoken text. Applies to: read-aloud. Studio: Settings → Deck → Speech → Lexicon.	a nested map: word → how to say it	none
acronyms:	Acronym registry — term → spoken expansion (and an optional glossary definition). Applies to: read-aloud, and glossary: auto. Studio: Settings → Deck → Speech → Acronyms.	a nested map: term → expansion, optional definition	none
say:	Read-aloud text per slide — a nested map of slide number → what that slide says. A slide’s own <!-- say: --> wins over it. Applies to: read-aloud. One slide: <!-- say: … -->.	a nested map: slide number → what that slide says	none
greeting:	What a narrated deck says first — your own words, true for the stock greeting, or off. Applies to: narrated playback.	true · off	none
closing:	What a narrated deck says last — your own words, true for the stock closing, or off. Applies to: narrated playback.	true · off	none

Export targets

What the command-line render produces. The Studio decides these in Share instead.

Key	What it does	Values	Default
present:	Open the exported PDF in presentation mode. CLI and front matter only — the Studio sets it at export. Applies to: command-line export only; yes/on and no/off also work.	true · false	false
read:	Emit the .html as the reading article — prose instead of the slide stack. CLI and front matter only — the Studio sets it at export. Applies to: command-line export only; yes/on and no/off also work.	true · false	false
fluid:	Emit the .html as the responsive fluid-box viewer — each slide fills the viewport and reflows to portrait on a phone. PDF/PPTX/PNG are unchanged. Applies to: command-line export only; yes/on and no/off also work.	true · false	false
player:	Emit the .html as the self-contained offline player (Present · Read Slides · Read Article). Supersedes fluid. Applies to: command-line export only; yes/on and no/off also work.	true · false	false

Raw styling

Marp-compatible CSS escape hatches. They bypass the theme, so reach for them last.

Key	What it does	Values	Default
style:	Raw CSS for this deck (a YAML block scalar). Applies to: command-line render only; the Studio preview and its exports ignore it.	CSS, as a YAML block (style: |)	none
color:	Text color on every slide — any CSS color. Quote a hex value: "#1a1a1a". One slide: <!-- _color: … -->.	a CSS color, quoted: "#1a1a1a"	the theme’s
backgroundColor:	Slide background color — any CSS color. Quote a hex value: "#ffffff". One slide: <!-- _backgroundColor: … -->.	a CSS color, quoted	the theme’s
backgroundImage:	Slide background image — a CSS value, e.g. url(./bg.png). One slide: <!-- _backgroundImage: … -->.	a CSS value, e.g. url(./bg.png)	none
backgroundPosition:	Where the background image sits — a CSS value, e.g. center. One slide: <!-- _backgroundPosition: … -->.	a CSS value	center
backgroundRepeat:	Whether the background image tiles — a CSS value, e.g. no-repeat. One slide: <!-- _backgroundRepeat: … -->.	a CSS value	no-repeat
backgroundSize:	Background image size — a CSS value, e.g. cover. One slide: <!-- _backgroundSize: … -->.	a CSS value	cover

Developer

Tools for building and checking a deck. None of them changes an export.

Key	What it does	Values	Default
profile:	Genre the Coach judges STYLE against — general (default), teaching, or mission. Never affects the Craft score. Applies to: Coach only; never the render. Studio: Settings → Deck → Coach → Style judged as.	general · teaching · mission	general
validate:	Inline validation in the editor — travels with the deck. Applies to: Studio editor only.	on · off	on
debug:	Layout debug overlay — preview-only, stripped from every export. Applies to: previews only; stripped from every export. Studio: Settings → Deck → General → Developer → Debug overlay. One slide: <!-- _debug: … -->.	off · on-hover · on-always, plus verbose	off