Best Practices Slide Design

---
name: best-practices-slide-design
description: >
  Slide design craft for /pitchdeck: assertion headlines, distance-legible
  chrome, multi-channel reinforcement, density limits, audience-parameterized
  arcs, responsive browser presentation, and house theme templates.
  Use when planning, drafting, critiquing, or restyling a deck; when slides look like "blue boxes"; when choosing layouts,
  fonts, or themes; or when converting a reference PPTX into a house style.
triggers:
  - design this slide
  - the slides look plain
  - make the deck look good
  - slide design best practices
  - pitch deck style
  - apply the house theme
  - analyze this pptx style
  - responsive slide design
provides:
  - slide-design-rules
  - theme-templates
  - style-reference-analysis
composes:
  - pitchdeck
  - agentic-evals
complies:
  - best-practices-skills
domains:
  - marketing
disciplines:
  - engineering-standards
  - content-creation
---

# Slide Design Best Practices

Craft rules for turning claim-honest deck drafts into persuasive slides.
House-style rules cite exemplar slides rendered from the human's REAL decks
(`references/exemplars.yaml`, images in `assets/`). Responsive browser rules
below are delivery constraints, not measurements from that fixed-slide corpus.
Design is ADVISORY; claims are LAW — nothing here overrides the pitchdeck
compiler's gates.

## The three principles (from the deck author, 2026-08-06)

1. **Distance legibility drives chrome.** The header band exists so header
   and body separate at 5–20 ft. If a slide's title zone is not
   distinguishable at thumbnail scale, it fails. (`cybersummit-04`)
2. **Animation is rhetorical.** Builds reveal in the order the argument
   unfolds; motion with no argumentative role is noise. Duplicated-slide
   runs that fake builds become `ContentReveal.STEP` fragments.
   (`cybersummit-42..45`, anti-exemplar)
3. **Multi-channel reinforcement.** Headline asserts it, chevrons state it,
   the diagram shows it, the metaphor badge sets the emotional register —
   the SAME idea on every channel. Text-only slides get a reinforcement
   proposal; text and visual making different points is a failure.
   (`cybersummit-18`)

## The archetype catalog

`references/DESIGN_SLIDES.md` classifies ALL 263 corpus slides into ten
archetypes (assertion+art 30%, section-divider 20%, bullets, art-rich,
dense-reference, mixed Q&A, art-only, close, toc, cover) with measured
geometry, exemplars, cross-archetype design laws, and the compiler mapping or
gap for each. Pick the archetype before composing; the machine-readable
assignment lives in outputs/house-slides/archetypes.json.

## Slide-level rules

| Rule | Statement | Exemplar |
|------|-----------|----------|
| headline-as-assertion | Titles are takeaways ("LLMs are Expensive"), never labels ("Cost Analysis") | cybersummit-49 |
| thesis-as-statement | Thesis = ONE hero-size assertion (64–112pt) + one icon; required qualifiers visible in footer, supporting detail in notes | reqml-12 |
| density-5x5 | ≤5 words/line, ≤5 lines, ≤4 takeaways before a visual; median ~16–33 words/slide | anti: cybersummit-21 (224 words) |
| one-big-diagram | Process/how slides earn ONE large diagram with labeled endpoints, not bullet paragraphs | cybersummit-12, cybersummit-18 |
| one-idea-per-slide | Channels must agree on a single idea; split slides that argue two things | cybersummit-18 |
| builds-are-fragments | Reveal order = narrative order, via fragments, never duplicated slides | anti: cybersummit-42..45 |
| cover-brand | Cover = wordmark + one-phrase tagline + brand glyph, ~5 words | cybersummit-01 |
| recap-device | Long decks restate the core assertion mid-deck ("What's the point, again?") | reqml-12 |

## Fonts and styling (house profile)

Measured across 6 real decks (2023–2026, all audiences) — see
`/mnt/storage12tb/skills/pitchdeck/outputs/style-references/` for per-deck
profiles and `house-style-synthesis.yaml` for the corpus synthesis.

- **Type**: Calibri (humanist sans) everywhere; Consolas for code; Roboto in
  diagrams. Scale: 64pt hero (112pt statement slides) / 36 section / 28 title
  / 24 lead / 20 body / 16 support / 12 caption.
- **Color**: petrol `#065E7C` primary (brand constant across every deck);
  ink `#292929` (never pure black in body); warm `#D39500`/gold `#D6A300`
  and green `#6F8E30` as inline emphasis; program-blue `#26558E` joins for
  DARPA/PI audiences; red sparingly (`#A14240`).
- **Chrome**: full-width teal header band with white title; circular
  line-icon metaphor badge top-right; footer = distribution statement +
  page number (+ sponsor strip on public decks).
- **Bullets**: teal chevron `>` level 1, small square level 2, em-dash
  level 3; key words emphasized inline via underline or warm color, and
  color-coded label prefixes (**Problems/Goal/Solution/Impact**).

## Responsive browser presentation

A browser deck is a reading surface, not just a scaled PowerPoint canvas.
The measured archetypes and point sizes above guide fixed exports and desktop
composition; they are not rigid geometry or font-size rules for narrow windows.

- **Reflow, do not shrink:** adapt to the available slide pane, including a
  half-screen window beside VS Code. Stack columns/cards and wrap text while
  preserving headline/body hierarchy. Use readable CSS type sizes; do not meet
  density budgets by shrinking, clipping, or deleting content.
- **Preserve the argument:** retain slide order, reading order, claims, source
  bindings, and rhetorical build order. Required visible qualifiers and
  distribution statements remain visible content, never notes-only, tooltips,
  or collapsed controls. Reflow must not summarize or strengthen a claim.
- **Preserve visual meaning:** keep diagram labels, directed relationships,
  legends, and captions readable. An explicit labeled relationship view is
  acceptable; stacking nodes alone must not imply a different graph. Complex
  diagrams may scroll locally, with a keyboard-accessible region, rather than
  shrinking labels indefinitely.
- **Contain imagery:** preserve aspect ratios and evidence-bearing regions.
  Do not crop away labels or evidence to fit a narrow pane.
- **Keep controls usable:** allow vertical reading scroll without viewport-wide
  horizontal overflow. Keep previous/next controls available; vertical keys
  scroll a focused reading region, while Left/Right navigate slides. Preserve
  focus visibility, interactive-control key handling, and reduced motion.
- **Keep exports separate:** responsive reading never writes back canonical
  element coordinates. Design editing, PPTX, and PDF retain fixed geometry;
  browser reflow is not proof of graphical parity with exported slides.
- **Verify the actual page:** inspect live Surf captures at desktop, half-screen,
  and phone widths, including below-the-fold qualifiers and diagram labels.
  Retained evals must check content retention, readable type, overflow,
  navigation, unchanged export geometry, and rejection of whole-slide scaling.

Use `$best-practices-react` for implementation/accessibility details. Breakpoints
belong to `$pitchdeck`, not to a universal house-style law. Its current behavior
and retained live gate are documented in
[`../pitchdeck/docs/RESPONSIVE_BROWSER.md`](../pitchdeck/docs/RESPONSIVE_BROWSER.md)
and [`../pitchdeck/fixtures/responsive_browser.json`](../pitchdeck/fixtures/responsive_browser.json).
Those cases cover their tested decks, not every arbitrary slide composition.

## Theme templates (`themes/*.json`, `pitchdeck.theme_template.v1`)

Drop-in themes for /pitchdeck. `theme_tokens` maps directly onto today's
`ThemeTokens` (accent, heading_font, body_font); the full palette, type
scale, chrome, and density budgets are staged for the extended tokens
(#1262). Audience is a PARAMETER, not a new design:

| Template | Audience | What changes |
|----------|----------|--------------|
| sparta-house-conference | conference talks | humor devices, metaphor badges, big icon diagrams |
| sparta-house-sbir | SBIR / investors | value prop before ToC, gold up-weighted, humor down |
| sparta-house-program-review | DARPA / PI meetings | program-blue, early pipeline-position slide, accomplishments section, notice slide, recap devices |

## Deck arc

Decks are ASSEMBLED from reusable modules, not drafted from scratch: the
ACERT mini-arc (Origin → Problem-Solution → How → Journey) appears nearly
verbatim in four decks. Standard arc: cover → ToC → value prop →
problem/solution → vision → product mini-arcs → roadmap → discussion,
with a Boneyard appendix absorbing overflow. Audience templates reorder
this arc (`arc_overrides`), never invent a new one.

## How to apply

- **Planning**: pick the audience template; draft the narrative arc first;
  slot claim-bound modules into it; every slide gets an assertion headline
  bound to spans (NUMERIC_UNBOUND keeps "70% faster" honest).
- **Critique**: score each slide against the rules table; emit advisory
  `DESIGN_*` findings with the violated rule + exemplar; propose fixes as
  simulate-validated EditProposals (layout changes stay governance-gated).
- **New style reference**: analyze a PPTX with python-pptx (fonts, colors,
  sizes, words/slide, shape census) + render representative slides; write a
  `pitchdeck.style_reference.v1` YAML next to the existing profiles.