Frontend Slides

Frontend Slides

Create zero-dependency, animation-rich HTML presentations that run entirely in the browser.

Inspired by the visual exploration approach showcased in work by zarazhangrui (credit: @zarazhangrui).

When to Activate

• Creating a talk deck, pitch deck, workshop deck, or internal presentation
• Converting .ppt or .pptx slides into an HTML presentation
• Improving an existing HTML presentation's layout, motion, or typography
• Exploring presentation styles with a user who does not know their design preference yet

Non-Negotiables

1. Zero dependencies: default to one self-contained HTML file with inline CSS and JS. 2. Viewport fit is mandatory: every slide must fit inside one viewport with no internal scrolling. 3. Show, don't tell: use visual previews instead of abstract style questionnaires. 4. Distinctive design: avoid generic purple-gradient, Inter-on-white, template-looking decks. 5. Production quality: keep code commented, accessible, responsive, and performant.

Before generating, read STYLE_PRESETS.md for the viewport-safe CSS base, density limits, preset catalog, and CSS gotchas.

Workflow

1. Detect Mode

Choose one path:

• New presentation: user has a topic, notes, or full draft
• PPT conversion: user has .ppt or .pptx
• Enhancement: user already has HTML slides and wants improvements

2. Discover Content

Ask only the minimum needed:

• purpose: pitch, teaching, conference talk, internal update
• length: short (5-10), medium (10-20), long (20+)
• content state: finished copy, rough notes, topic only

If the user has content, ask them to paste it before styling.

3. Discover Style

Default to visual exploration.

If the user already knows the desired preset, skip previews and use it directly.

Otherwise: 1. Ask what feeling the deck should create: impressed, energized, focused, inspired. 2. Generate 3 single-slide preview files in .ecc-design/slide-previews/. 3. Each preview must be self-contained, show typography/color/motion clearly, and stay under roughly 100 lines of slide content. 4. Ask the user which preview to keep or what elements to mix.

Use the preset guide in STYLE_PRESETS.md when mapping mood to style.

4. Build the Presentation

Output either:

• presentation.html
• [presentation-name].html

Use an assets/ folder only when the deck contains extracted or user-supplied images.

Required structure:

• semantic slide sections
• a viewport-safe CSS base from STYLE_PRESETS.md
• CSS custom properties for theme values
• a presentation controller class for keyboard, wheel, and touch navigation
• Intersection Observer for reveal animations
• reduced-motion support

5. Enforce Viewport Fit

Treat this as a hard gate.

Rules:

• every .slide must use height: 100vh; height: 100dvh; overflow: hidden;
• all type and spacing must scale with clamp()
• when content does not fit, split into multiple slides
• never solve overflow by shrinking text below readable sizes
• never allow scrollbars inside a slide

Use the density limits and mandatory CSS block in STYLE_PRESETS.md.

6. Validate

Check the finished deck at these sizes:

• 1920x1080
• 1280x720
• 768x1024
• 375x667
• 667x375

If browser automation is available, use it to verify no slide overflows and that keyboard navigation works.

7. Deliver

At handoff:

• delete temporary preview files unless the user wants to keep them
• open the deck with the platform-appropriate opener when useful
• summarize file path, preset used, slide count, and easy theme customization points

Use the correct opener for the current OS:

• macOS: open file.html
• Linux: xdg-open file.html
• Windows: start "" file.html

PPT / PPTX Conversion

For PowerPoint conversion: 1. Prefer python3 with python-pptx to extract text, images, and notes. 2. If python-pptx is unavailable, ask whether to install it or fall back to a manual/export-based workflow. 3. Preserve slide order, speaker notes, and extracted assets. 4. After extraction, run the same style-selection workflow as a new presentation.

Keep conversion cross-platform. Do not rely on macOS-only tools when Python can do the job.

Implementation Requirements

HTML / CSS

• Use inline CSS and JS unless the user explicitly wants a multi-file project.
• Fonts may come from Google Fonts or Fontshare.
• Prefer atmospheric backgrounds, strong type hierarchy, and a clear visual direction.
• Use abstract shapes, gradients, grids, noise, and geometry rather than illustrations.

JavaScript

Include:

• keyboard navigation
• touch / swipe navigation
• mouse wheel navigation
• progress indicator or slide index
• reveal-on-enter animation triggers

Accessibility

• use semantic structure (main, section, nav)
• keep contrast readable
• support keyboard-only navigation
• respect prefers-reduced-motion

Content Density Limits

Use these maxima unless the user explicitly asks for denser slides and readability still holds:

Anti-Patterns

• generic startup gradients with no visual identity
• system-font decks unless intentionally editorial
• long bullet walls
• code blocks that need scrolling
• fixed-height content boxes that break on short screens
• invalid negated CSS functions like -clamp(...)

Related ECC Skills

• frontend-patterns for component and interaction patterns around the deck
• liquid-glass-design when a presentation intentionally borrows Apple glass aesthetics
• e2e-testing if you need automated browser verification for the final deck

Deliverable Checklist

• presentation runs from a local file in a browser
• every slide fits the viewport without scrolling
• style is distinctive and intentional
• animation is meaningful, not noisy
• reduced motion is respected
• file paths and customization points are explained at handoff

Animation Patterns Reference

Use this reference when generating presentations. Match animations to the intended feeling.

Effect-to-Feeling Guide

Entrance Animations

/* Fade + Slide Up (most versatile) */
.reveal {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s var(--ease-out-expo),
                transform 0.6s var(--ease-out-expo);
}
.visible .reveal {
    opacity: 1;
    transform: translateY(0);
}

/* Scale In */
.reveal-scale {
    opacity: 0;
    transform: scale(0.9);
    transition: opacity 0.6s, transform 0.6s var(--ease-out-expo);
}
.visible .reveal-scale {
    opacity: 1;
    transform: scale(1);
}

/* Slide from Left */
.reveal-left {
    opacity: 0;
    transform: translateX(-50px);
    transition: opacity 0.6s, transform 0.6s var(--ease-out-expo);
}
.visible .reveal-left {
    opacity: 1;
    transform: translateX(0);
}

/* Blur In */
.reveal-blur {
    opacity: 0;
    filter: blur(10px);
    transition: opacity 0.8s, filter 0.8s var(--ease-out-expo);
}
.visible .reveal-blur {
    opacity: 1;
    filter: blur(0);
}

Background Effects

/* Gradient Mesh — layered radial gradients for depth */
.gradient-bg {
    background:
        radial-gradient(ellipse at 20% 80%, rgba(120, 0, 255, 0.3) 0%, transparent 50%),
        radial-gradient(ellipse at 80% 20%, rgba(0, 255, 200, 0.2) 0%, transparent 50%),
        var(--bg-primary);
}

/* Noise Texture — inline SVG for grain */
.noise-bg {
    background-image: url("data:image/svg+xml,..."); /* Inline SVG noise */
}

/* Grid Pattern — subtle structural lines */
.grid-bg {
    background-image:
        linear-gradient(rgba(255,255,255,0.03) 1px, transparent 1px),
        linear-gradient(90deg, rgba(255,255,255,0.03) 1px, transparent 1px);
    background-size: 50px 50px;
}

Interactive Effects

/* 3D Tilt on Hover — adds depth to cards/panels */
class TiltEffect {
    constructor(element) {
        this.element = element;
        this.element.style.transformStyle = 'preserve-3d';
        this.element.style.perspective = '1000px';

        this.element.addEventListener('mousemove', (e) => {
            const rect = this.element.getBoundingClientRect();
            const x = (e.clientX - rect.left) / rect.width - 0.5;
            const y = (e.clientY - rect.top) / rect.height - 0.5;
            this.element.style.transform = `rotateY(${x * 10}deg) rotateX(${-y * 10}deg)`;
        });

        this.element.addEventListener('mouseleave', () => {
            this.element.style.transform = 'rotateY(0) rotateX(0)';
        });
    }
}

Troubleshooting

HTML Presentation Template

Reference architecture for generating slide presentations. Every presentation follows this structure.

Base HTML Structure

<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Presentation Title</title>

    <!-- Fonts: use Fontshare or Google Fonts — never system fonts -->
    <link rel="stylesheet" href="https://api.fontshare.com/v2/css?f[]=..." />

    <style>
      /* ===========================================
           CSS CUSTOM PROPERTIES (THEME)
           Change these to change the whole look
           =========================================== */
      :root {
        /* Colors — from chosen style preset */
        --bg-primary: #0a0f1c;
        --bg-secondary: #111827;
        --text-primary: #ffffff;
        --text-secondary: #9ca3af;
        --accent: #00ffcc;
        --accent-glow: rgba(0, 255, 204, 0.3);

        /* Typography — MUST use clamp() */
        --font-display: "Clash Display", sans-serif;
        --font-body: "Satoshi", sans-serif;
        --title-size: clamp(2rem, 6vw, 5rem);
        --subtitle-size: clamp(0.875rem, 2vw, 1.25rem);
        --body-size: clamp(0.75rem, 1.2vw, 1rem);

        /* Spacing — MUST use clamp() */
        --slide-padding: clamp(1.5rem, 4vw, 4rem);
        --content-gap: clamp(1rem, 2vw, 2rem);

        /* Animation */
        --ease-out-expo: cubic-bezier(0.16, 1, 0.3, 1);
        --duration-normal: 0.6s;
      }

      /* ===========================================
           BASE STYLES
           =========================================== */
      * {
        margin: 0;
        padding: 0;
        box-sizing: border-box;
      }

      /* --- PASTE viewport-base.css CONTENTS HERE --- */

      /* ===========================================
           ANIMATIONS
           Trigger via .visible class (added by JS on scroll)
           =========================================== */
      .reveal {
        opacity: 0;
        transform: translateY(30px);
        transition:
          opacity var(--duration-normal) var(--ease-out-expo),
          transform var(--duration-normal) var(--ease-out-expo);
      }

      .slide.visible .reveal {
        opacity: 1;
        transform: translateY(0);
      }

      /* Stagger children for sequential reveal */
      .reveal:nth-child(1) {
        transition-delay: 0.1s;
      }
      .reveal:nth-child(2) {
        transition-delay: 0.2s;
      }
      .reveal:nth-child(3) {
        transition-delay: 0.3s;
      }
      .reveal:nth-child(4) {
        transition-delay: 0.4s;
      }

      /* ... preset-specific styles ... */
    </style>
  </head>
  <body>
    <!-- Optional: Progress bar -->
    <div class="progress-bar"></div>

    <!-- Optional: Navigation dots -->
    <nav class="nav-dots"><!-- Generated by JS --></nav>

    <!-- Slides -->
    <section class="slide title-slide">
      <h1 class="reveal">Presentation Title</h1>
      <p class="reveal">Subtitle or author</p>
    </section>

    <section class="slide">
      <div class="slide-content">
        <h2 class="reveal">Slide Title</h2>
        <p class="reveal">Content...</p>
      </div>
    </section>

    <!-- More slides... -->

    <script>
      /* ===========================================
           SLIDE PRESENTATION CONTROLLER
           =========================================== */
      class SlidePresentation {
        constructor() {
          this.slides = document.querySelectorAll(".slide");
          this.currentSlide = 0;
          this.setupIntersectionObserver();
          this.setupKeyboardNav();
          this.setupTouchNav();
          this.setupProgressBar();
          this.setupNavDots();
        }

        setupIntersectionObserver() {
          // Add .visible class when slides enter viewport
          // Triggers CSS animations efficiently
        }

        setupKeyboardNav() {
          // Arrow keys, Space, Page Up/Down
        }

        setupTouchNav() {
          // Touch/swipe support for mobile
        }

        setupProgressBar() {
          // Update progress bar on scroll
        }

        setupNavDots() {
          // IMPORTANT: Always clear before building — if outerHTML was
          // captured while dots were rendered, re-opening the file would
          // append a duplicate set on top of the existing ones.
          this.navDotsContainer.innerHTML = "";
          // Generate and manage navigation dots
        }
      }

      new SlidePresentation();
    </script>
  </body>
</html>

Required JavaScript Features

Every presentation must include:

1. SlidePresentation Class — Main controller with:

• Keyboard navigation (arrows, space, page up/down)
• Touch/swipe support
• Mouse wheel navigation
• Progress bar updates
• Navigation dots

2. Intersection Observer — For scroll-triggered animations:

• Add .visible class when slides enter viewport
• Trigger CSS transitions efficiently

3. Optional Enhancements (match to chosen style):

• Custom cursor with trail
• Particle system background (canvas)
• Parallax effects
• 3D tilt on hover
• Magnetic buttons
• Counter animations

4. Inline Editing (only if user opted in during Phase 1 — skip entirely if they said No):

• Edit toggle button (hidden by default, revealed via hover hotzone or E key)
• Auto-save to localStorage
• Export/save file functionality
• See "Inline Editing Implementation" section below

Inline Editing Implementation (Opt-In Only)

If the user chose "No" for inline editing in Phase 1, do NOT generate any edit-related HTML, CSS, or JS.

Do NOT use CSS `~` sibling selector for hover-based show/hide. The CSS-only approach (edit-hotzone:hover ~ .edit-toggle) fails because pointer-events: none on the toggle button breaks the hover chain: user hovers hotzone -> button becomes visible -> mouse moves toward button -> leaves hotzone -> button disappears before click.

Required approach: JS-based hover with 400ms delay timeout.

HTML:

<div class="edit-hotzone"></div>
<button class="edit-toggle" id="editToggle" title="Edit mode (E)">Edit</button>

CSS (visibility controlled by JS classes only):

/* Do NOT use CSS ~ sibling selector for this!
   pointer-events: none breaks the hover chain.
   Must use JS with delay timeout. */
.edit-hotzone {
  position: fixed;
  top: 0;
  left: 0;
  width: 80px;
  height: 80px;
  z-index: 10000;
  cursor: pointer;
}
.edit-toggle {
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.3s ease;
  z-index: 10001;
}
.edit-toggle.show,
.edit-toggle.active {
  opacity: 1;
  pointer-events: auto;
}

JS (three interaction methods):

// 1. Click handler on the toggle button
document.getElementById("editToggle").addEventListener("click", () => {
  editor.toggleEditMode();
});

// 2. Hotzone hover with 400ms grace period
const hotzone = document.querySelector(".edit-hotzone");
const editToggle = document.getElementById("editToggle");
let hideTimeout = null;

hotzone.addEventListener("mouseenter", () => {
  clearTimeout(hideTimeout);
  editToggle.classList.add("show");
});
hotzone.addEventListener("mouseleave", () => {
  hideTimeout = setTimeout(() => {
    if (!editor.isActive) editToggle.classList.remove("show");
  }, 400);
});
editToggle.addEventListener("mouseenter", () => {
  clearTimeout(hideTimeout);
});
editToggle.addEventListener("mouseleave", () => {
  hideTimeout = setTimeout(() => {
    if (!editor.isActive) editToggle.classList.remove("show");
  }, 400);
});

// 3. Hotzone direct click
hotzone.addEventListener("click", () => {
  editor.toggleEditMode();
});

// 4. Keyboard shortcut (E key, skip when editing text)
document.addEventListener("keydown", (e) => {
  if (
    (e.key === "e" || e.key === "E") &&
    !e.target.getAttribute("contenteditable")
  ) {
    editor.toggleEditMode();
  }
});

CRITICAL: `exportFile()` must strip edit state before capturing outerHTML.

When the user presses Ctrl+S in edit mode, document.documentElement.outerHTML captures the live DOM — including body.edit-active, contenteditable="true" on every text element, and .active/.show classes on the toggle button and banner. Anyone opening the saved file sees dashed outlines, a checkmark button, and an edit banner, as if permanently stuck in edit mode.

Always implement exportFile() like this:

exportFile() {
    // Temporarily strip edit state so the saved file opens cleanly
    const editableEls = Array.from(document.querySelectorAll('[contenteditable]'));
    editableEls.forEach(el => el.removeAttribute('contenteditable'));
    document.body.classList.remove('edit-active');

    // Also strip UI classes from toggle button and banner
    const editToggle = document.getElementById('editToggle');
    const editBanner = document.querySelector('.edit-banner');
    editToggle?.classList.remove('active', 'show');
    editBanner?.classList.remove('active', 'show');

    const html = '<!DOCTYPE html>\n' + document.documentElement.outerHTML;

    // Restore edit state so the user can keep editing
    document.body.classList.add('edit-active');
    editableEls.forEach(el => el.setAttribute('contenteditable', 'true'));
    editToggle?.classList.add('active');
    editBanner?.classList.add('active');

    const blob = new Blob([html], { type: 'text/html' });
    const a = document.createElement('a');
    a.href = URL.createObjectURL(blob);
    a.download = 'presentation.html';
    a.click();
    URL.revokeObjectURL(a.href);
}

Image Pipeline (Skip If No Images)

If user chose "No images" in Phase 1, skip this entirely. If images were provided, process them before generating HTML.

Dependency: pip install Pillow

Image Processing

from PIL import Image, ImageDraw

# Circular crop (for logos on modern/clean styles)
def crop_circle(input_path, output_path):
    img = Image.open(input_path).convert('RGBA')
    w, h = img.size
    size = min(w, h)
    left, top = (w - size) // 2, (h - size) // 2
    img = img.crop((left, top, left + size, top + size))
    mask = Image.new('L', (size, size), 0)
    ImageDraw.Draw(mask).ellipse([0, 0, size, size], fill=255)
    img.putalpha(mask)
    img.save(output_path, 'PNG')

# Resize (for oversized images that inflate HTML)
def resize_max(input_path, output_path, max_dim=1200):
    img = Image.open(input_path)
    img.thumbnail((max_dim, max_dim), Image.LANCZOS)
    img.save(output_path, quality=85)

Save processed images with _processed suffix. Never overwrite originals.

Image Placement

Use direct file paths (not base64) — presentations are viewed locally:

<img src="assets/logo_round.png" alt="Logo" class="slide-image logo" />
<img
  src="assets/screenshot.png"
  alt="Screenshot"
  class="slide-image screenshot"
/>

.slide-image {
  max-width: 100%;
  max-height: min(50vh, 400px);
  object-fit: contain;
  border-radius: 8px;
}
.slide-image.screenshot {
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: 12px;
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
}
.slide-image.logo {
  max-height: min(30vh, 200px);
}

Adapt border/shadow colors to match the chosen style's accent. Never repeat the same image on multiple slides (except logos on title + closing).

Placement patterns: Logo centered on title slide. Screenshots in two-column layouts with text. Full-bleed images as slide backgrounds with text overlay (use sparingly).

---

Code Quality

Comments: Every section needs clear comments explaining what it does and how to modify it.

Accessibility:

• Semantic HTML (<section>, <nav>, <main>)
• Keyboard navigation works fully
• ARIA labels where needed
• prefers-reduced-motion support (included in viewport-base.css)

File Structure

Single presentations:

presentation.html    # Self-contained, all CSS/JS inline
assets/              # Images only, if any

Multiple presentations in one project:

[name].html
[name]-assets/

Style Presets Reference

Curated visual styles for frontend-slides.

Use this file for:

• the mandatory viewport-fitting CSS base
• preset selection and mood mapping
• CSS gotchas and validation rules

Abstract shapes only. Avoid illustrations unless the user explicitly asks for them.

Viewport Fit Is Non-Negotiable

Every slide must fully fit in one viewport.

Golden Rule

Each slide = exactly one viewport height.
Too much content = split into more slides.
Never scroll inside a slide.

Density Limits

Mandatory Base CSS

Copy this block into every generated presentation and then theme on top of it.

/* ===========================================
   VIEWPORT FITTING: MANDATORY BASE STYLES
   =========================================== */

html, body {
    height: 100%;
    overflow-x: hidden;
}

html {
    scroll-snap-type: y mandatory;
    scroll-behavior: smooth;
}

.slide {
    width: 100vw;
    height: 100vh;
    height: 100dvh;
    overflow: hidden;
    scroll-snap-align: start;
    display: flex;
    flex-direction: column;
    position: relative;
}

.slide-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    justify-content: center;
    max-height: 100%;
    overflow: hidden;
    padding: var(--slide-padding);
}

:root {
    --title-size: clamp(1.5rem, 5vw, 4rem);
    --h2-size: clamp(1.25rem, 3.5vw, 2.5rem);
    --h3-size: clamp(1rem, 2.5vw, 1.75rem);
    --body-size: clamp(0.75rem, 1.5vw, 1.125rem);
    --small-size: clamp(0.65rem, 1vw, 0.875rem);

    --slide-padding: clamp(1rem, 4vw, 4rem);
    --content-gap: clamp(0.5rem, 2vw, 2rem);
    --element-gap: clamp(0.25rem, 1vw, 1rem);
}

.card, .container, .content-box {
    max-width: min(90vw, 1000px);
    max-height: min(80vh, 700px);
}

.feature-list, .bullet-list {
    gap: clamp(0.4rem, 1vh, 1rem);
}

.feature-list li, .bullet-list li {
    font-size: var(--body-size);
    line-height: 1.4;
}

.grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(min(100%, 250px), 1fr));
    gap: clamp(0.5rem, 1.5vw, 1rem);
}

img, .image-container {
    max-width: 100%;
    max-height: min(50vh, 400px);
    object-fit: contain;
}

@media (max-height: 700px) {
    :root {
        --slide-padding: clamp(0.75rem, 3vw, 2rem);
        --content-gap: clamp(0.4rem, 1.5vw, 1rem);
        --title-size: clamp(1.25rem, 4.5vw, 2.5rem);
        --h2-size: clamp(1rem, 3vw, 1.75rem);
    }
}

@media (max-height: 600px) {
    :root {
        --slide-padding: clamp(0.5rem, 2.5vw, 1.5rem);
        --content-gap: clamp(0.3rem, 1vw, 0.75rem);
        --title-size: clamp(1.1rem, 4vw, 2rem);
        --body-size: clamp(0.7rem, 1.2vw, 0.95rem);
    }

    .nav-dots, .keyboard-hint, .decorative {
        display: none;
    }
}

@media (max-height: 500px) {
    :root {
        --slide-padding: clamp(0.4rem, 2vw, 1rem);
        --title-size: clamp(1rem, 3.5vw, 1.5rem);
        --h2-size: clamp(0.9rem, 2.5vw, 1.25rem);
        --body-size: clamp(0.65rem, 1vw, 0.85rem);
    }
}

@media (max-width: 600px) {
    :root {
        --title-size: clamp(1.25rem, 7vw, 2.5rem);
    }

    .grid {
        grid-template-columns: 1fr;
    }
}

@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after {
        animation-duration: 0.01ms !important;
        transition-duration: 0.2s !important;
    }

    html {
        scroll-behavior: auto;
    }
}

Viewport Checklist

• every .slide has height: 100vh, height: 100dvh, and overflow: hidden
• all typography uses clamp()
• all spacing uses clamp() or viewport units
• images have max-height constraints
• grids adapt with auto-fit + minmax()
• short-height breakpoints exist at 700px, 600px, and 500px
• if anything feels cramped, split the slide

Mood to Preset Mapping

Preset Catalog

1. Bold Signal

• Vibe: confident, high-impact, keynote-ready
• Best for: pitch decks, launches, statements
• Fonts: Archivo Black + Space Grotesk
• Palette: charcoal base, hot orange focal card, crisp white text
• Signature: oversized section numbers, high-contrast card on dark field

2. Electric Studio

• Vibe: clean, bold, agency-polished
• Best for: client presentations, strategic reviews
• Fonts: Manrope only
• Palette: black, white, saturated cobalt accent
• Signature: two-panel split and sharp editorial alignment

3. Creative Voltage

• Vibe: energetic, retro-modern, playful confidence
• Best for: creative studios, brand work, product storytelling
• Fonts: Syne + Space Mono
• Palette: electric blue, neon yellow, deep navy
• Signature: halftone textures, badges, punchy contrast

4. Dark Botanical

• Vibe: elegant, premium, atmospheric
• Best for: luxury brands, thoughtful narratives, premium product decks
• Fonts: Cormorant + IBM Plex Sans
• Palette: near-black, warm ivory, blush, gold, terracotta
• Signature: blurred abstract circles, fine rules, restrained motion

5. Notebook Tabs

• Vibe: editorial, organized, tactile
• Best for: reports, reviews, structured storytelling
• Fonts: Bodoni Moda + DM Sans
• Palette: cream paper on charcoal with pastel tabs
• Signature: paper sheet, colored side tabs, binder details

6. Pastel Geometry

• Vibe: approachable, modern, friendly
• Best for: product overviews, onboarding, lighter brand decks
• Fonts: Plus Jakarta Sans only
• Palette: pale blue field, cream card, soft pink/mint/lavender accents
• Signature: vertical pills, rounded cards, soft shadows

7. Split Pastel

• Vibe: playful, modern, creative
• Best for: agency intros, workshops, portfolios
• Fonts: Outfit only
• Palette: peach + lavender split with mint badges
• Signature: split backdrop, rounded tags, light grid overlays

8. Vintage Editorial

• Vibe: witty, personality-driven, magazine-inspired
• Best for: personal brands, opinionated talks, storytelling
• Fonts: Fraunces + Work Sans
• Palette: cream, charcoal, dusty warm accents
• Signature: geometric accents, bordered callouts, punchy serif headlines

9. Neon Cyber

• Vibe: futuristic, techy, kinetic
• Best for: AI, infra, dev tools, future-of-X talks
• Fonts: Clash Display + Satoshi
• Palette: midnight navy, cyan, magenta
• Signature: glow, particles, grids, data-radar energy

10. Terminal Green

• Vibe: developer-focused, hacker-clean
• Best for: APIs, CLI tools, engineering demos
• Fonts: JetBrains Mono only
• Palette: GitHub dark + terminal green
• Signature: scan lines, command-line framing, precise monospace rhythm

11. Swiss Modern

• Vibe: minimal, precise, data-forward
• Best for: corporate, product strategy, analytics
• Fonts: Archivo + Nunito
• Palette: white, black, signal red
• Signature: visible grids, asymmetry, geometric discipline

12. Paper & Ink

• Vibe: literary, thoughtful, story-driven
• Best for: essays, keynote narratives, manifesto decks
• Fonts: Cormorant Garamond + Source Serif 4
• Palette: warm cream, charcoal, crimson accent
• Signature: pull quotes, drop caps, elegant rules

Direct Selection Prompts

If the user already knows the style they want, let them pick directly from the preset names above instead of forcing preview generation.

Animation Feel Mapping

CSS Gotcha: Negating Functions

Never write these:

right: -clamp(28px, 3.5vw, 44px);
margin-left: -min(10vw, 100px);

Browsers ignore them silently.

Always write this instead:

right: calc(-1 * clamp(28px, 3.5vw, 44px));
margin-left: calc(-1 * min(10vw, 100px));

Validation Sizes

Test at minimum:

• Desktop: 1920x1080, 1440x900, 1280x720
• Tablet: 1024x768, 768x1024
• Mobile: 375x667, 414x896
• Landscape phone: 667x375, 896x414

Anti-Patterns

Do not use:

• purple-on-white startup templates
• Inter / Roboto / Arial as the visual voice unless the user explicitly wants utilitarian neutrality
• bullet walls, tiny type, or code blocks that require scrolling
• decorative illustrations when abstract geometry would do the job better