Revealjs Slides

reveal.js Slide Generator

Workflow

1. Copy template from assets/template.html to the user's target path (default: slides.html in cwd)
2. Replace {{TITLE}}, {{SUBTITLE}}, {{AUTHOR}}, {{DATE}} placeholders
3. Generate <section> elements for each slide between the TITLE SLIDE and closing comments
4. Serve and open the presentation (see Running below)

Running

After generating the HTML file, always serve and open it for the user.

npx live-server --port=8765 --open=slides.html

Keyboard shortcuts in the presentation:

• Arrow keys / Space — navigate slides
• S — open speaker notes view
• O — overview / slide grid
• F — fullscreen
• Esc — exit overview or fullscreen
• B / . — pause (black screen)

Template Location

assets/template.html — CDN-based (no npm install needed), uses Inter font, custom theme, includes Markdown, Highlight, Notes, Math, and Mermaid plugins.

Default Theme: Custom-Style

The template ships with a custom theme built in. Key characteristics:

• Inter font (Google Fonts) with Segoe UI / Calibri fallbacks
• Left-aligned content slides with top-aligned text (center: false)
• Title/closing slides use class="title-slide" for centered, vertically-centered layout
• h2 slide titles have a subtle bottom border separator
• Bold text renders in the heading accent color (#1a3c6e)
• Tables have a dark navy header row with alternating striped rows
• Blockquotes have a left blue accent bar with light background
• Code blocks are flat with a subtle border (no drop shadow)
• Slide dimensions: 1280x720 (16:9), matching typical presentation aspect ratio
• Slide padding: 48px top/bottom, 56px sides

Title / closing slide (vertically centered)

<section class="title-slide">
  <h1>Presentation Title</h1>
  <p>Subtitle text here</p>
  <p class="small">Author &mdash; Date</p>
</section>

Two-column layout (using .columns helper)

<section>
  <h2>Comparison</h2>
  <div class="columns">
    <div><h3>Left</h3><p>Content</p></div>
    <div><h3>Right</h3><p>Content</p></div>
  </div>
</section>

Base Theme Override

The custom theme overrides white.css. To change the base, replace white in the CSS link: black, league, beige, night, serif, simple, solarized, moon, dracula, sky, blood. Note: for dark base themes, also update the CSS variable --r-heading-color and other colors.

Slide Patterns

Basic slide

<section>
  <h2>Title</h2>
  <p>Content here</p>
</section>

Bullet list with fragments (reveal one at a time)

<section>
  <h2>Key Points</h2>
  <ul>
    <li class="fragment">First point</li>
    <li class="fragment">Second point</li>
    <li class="fragment">Third point</li>
  </ul>
</section>

Code with syntax highlighting

<section>
  <h2>Code</h2>
  <pre><code class="language-python" data-trim data-line-numbers>
def hello():
    print("Hello, world!")
  </code></pre>
</section>

Use data-line-numbers="1-2|3-4" to step through line highlights.

Image slide

<section>
  <h2>Architecture</h2>
  <img src="diagram.png" alt="Architecture" style="max-height: 500px;">
</section>

Speaker notes

<section>
  <h2>Topic</h2>
  <p>Audience content</p>
  <aside class="notes">Speaker-only notes here. Press 's' to open speaker view.</aside>
</section>

Background color/image

<section data-background-color="#4d7e65">
  <h2>Green Background</h2>
</section>
<section data-background-image="photo.jpg" data-background-size="cover">
  <h2>Photo Background</h2>
</section>

Blockquote

<section>
  <blockquote>"Quote text here." &mdash; Author</blockquote>
</section>

Two-column layout

<section>
  <h2>Comparison</h2>
  <div style="display: flex; gap: 2em;">
    <div style="flex: 1;"><h3>Left</h3><p>Content</p></div>
    <div style="flex: 1;"><h3>Right</h3><p>Content</p></div>
  </div>
</section>

Math (KaTeX)

<section>
  <h2>Equation</h2>
  <p>\[ E = mc^2 \]</p>
</section>

Markdown slide

<section data-markdown>
  <script type="text/template">
    ## Markdown Title
    - Point **one**
    - Point *two*

    Notes:
    Speaker notes in markdown.
  </script>
</section>

Diagram Patterns (Mermaid.js)

The template includes the Mermaid plugin. Use <div class="mermaid"> blocks inside slides to render diagrams. Mermaid renders to SVG automatically — no images needed.

Flowchart

<section>
  <h2>User Flow</h2>
  <div class="mermaid">
    flowchart LR
      A[Visit Site] --> B{Logged in?}
      B -- Yes --> C[Dashboard]
      B -- No --> D[Login Page]
      D --> E[Enter Credentials]
      E --> C
  </div>
</section>

Sequence diagram

<section>
  <h2>API Request Flow</h2>
  <div class="mermaid">
    sequenceDiagram
      participant Client
      participant API
      participant DB
      Client->>API: POST /users
      API->>DB: INSERT user
      DB-->>API: user record
      API-->>Client: 201 Created
  </div>
</section>

Class diagram

<section>
  <h2>Domain Model</h2>
  <div class="mermaid">
    classDiagram
      class Animal {
        +String name
        +int age
        +makeSound()
      }
      class Dog {
        +fetch()
      }
      class Cat {
        +purr()
      }
      Animal <|-- Dog
      Animal <|-- Cat
  </div>
</section>

Entity-Relationship diagram

<section>
  <h2>Database Schema</h2>
  <div class="mermaid">
    erDiagram
      USER ||--o{ ORDER : places
      ORDER ||--|{ LINE_ITEM : contains
      PRODUCT ||--o{ LINE_ITEM : "ordered in"
  </div>
</section>

State diagram

<section>
  <h2>Order Lifecycle</h2>
  <div class="mermaid">
    stateDiagram-v2
      [*] --> Pending
      Pending --> Processing : payment received
      Processing --> Shipped : packed
      Shipped --> Delivered : arrived
      Delivered --> [*]
      Processing --> Cancelled : refund
  </div>
</section>

Mindmap

<section>
  <h2>Project Overview</h2>
  <div class="mermaid">
    mindmap
      root((Project))
        Frontend
          React
          Tailwind
        Backend
          Node.js
          PostgreSQL
        DevOps
          Docker
          CI/CD
  </div>
</section>

Timeline

<section>
  <h2>Project Milestones</h2>
  <div class="mermaid">
    timeline
      title Release Timeline
      Q1 2025 : Alpha release
                : Core features
      Q2 2025 : Beta release
                : API launch
      Q3 2025 : GA release
  </div>
</section>

Gantt chart

<section>
  <h2>Sprint Plan</h2>
  <div class="mermaid">
    gantt
      title Sprint 12
      dateFormat YYYY-MM-DD
      section Backend
        API endpoints :a1, 2025-01-06, 5d
        Database migration :a2, after a1, 3d
      section Frontend
        UI components :b1, 2025-01-06, 7d
        Integration :b2, after b1, 3d
  </div>
</section>

Pie chart

<section>
  <h2>Traffic Sources</h2>
  <div class="mermaid">
    pie title Traffic Sources
      "Organic Search" : 45
      "Direct" : 25
      "Social Media" : 20
      "Referral" : 10
  </div>
</section>

Git graph

<section>
  <h2>Branching Strategy</h2>
  <div class="mermaid">
    gitGraph
      commit
      branch feature
      checkout feature
      commit
      commit
      checkout main
      merge feature
      commit
  </div>
</section>

Diagram with custom theme (dark presentations)

For dark themes (black, night, dracula, league), add a theme directive:

<div class="mermaid">
  %%{init: {'theme': 'dark'}}%%
  flowchart LR
    A --> B --> C
</div>

Available Mermaid themes: default, dark, forest, neutral, base.

Diagram with title and description alongside

<section>
  <h2>Architecture</h2>
  <div class="columns">
    <div>
      <div class="mermaid">
        flowchart TD
          LB[Load Balancer] --> S1[Server 1]
          LB --> S2[Server 2]
          S1 --> DB[(Database)]
          S2 --> DB
      </div>
    </div>
    <div>
      <ul>
        <li>Horizontally scalable</li>
        <li>Single database with replicas</li>
        <li>Health-check based routing</li>
      </ul>
    </div>
  </div>
</section>

Diagram Design Guidelines

• One diagram per slide — keep diagrams readable; don't crowd
• Keep under 15-20 nodes — split complex systems across multiple slides
• Use meaningful labels — User, Database, not A, B, C
• Match the theme — use %%{init: {'theme': 'dark'}}%% for dark presentation themes
• Flowchart direction — use LR (left-to-right) for wide slides, TD (top-down) for tall diagrams
• Pair with text — use two-column layout to add context beside a diagram
• Prefer flowchart for: processes, decision trees, architecture
• Prefer sequence for: API flows, request/response, protocol interactions
• Prefer class/ER for: data models, database schemas, OOP hierarchies
• Prefer mindmap for: brainstorming, topic overviews, project structure
• Prefer timeline/gantt for: roadmaps, project plans, sprint schedules

Slide Design Guidelines

• Title slide: always first, use class="title-slide" with h1, subtitle, and author
• Closing slide: use class="title-slide" for centered "Questions?" or "Thank You" slides
• Content slides: use h2 for the slide title (gets a bottom border separator automatically)
• ~1 idea per slide: keep content focused
• Prefer fragments for bullet lists so content reveals progressively
• Code blocks: use data-trim to strip whitespace, set language-* class
• Limit text: prefer visuals, short phrases, and keywords over paragraphs
• Bold for emphasis: <strong> text renders in the navy accent color automatically
• Use .columns helper: for side-by-side layouts instead of inline flex styles
• Never use vertical slides: do not nest <section> inside <section>. All slides must be flat/horizontal only

Config Customization

Modify the Reveal.initialize({...}) block at the bottom of the HTML:

PDF Export

Append ?print-pdf to the URL and use browser print (Cmd/Ctrl+P) to save as PDF.