skills/athina-ai/goose-skills/visual-brand-extractor

visual-brand-extractor

SKILL.md

Visual Brand Extractor

Extract a client's visual identity from their website and generate reusable style presets for slides and content assets. This is an agent-executed skill — the AI reads pages via WebFetch and performs the analysis directly.

Quick Start

Extract visual branding from https://vapi.ai for the Vapi client.

Inputs

Input Required Description
Website URL Yes Client's homepage or landing page URL
Client name Yes For naming the output files
Additional pages No Product page, docs page, etc. for richer extraction

Output

Two files saved to clients/<client-name>/brand/visual-identity.md:

  1. Slide preset — CSS custom properties, typography, and signature elements matching the format in skills/create-html-slides/STYLE_PRESETS.md
  2. Brand config JSON — Simple color/font config matching skills/content-asset-creator format

Process

Phase 1: Fetch Target Pages

Fetch 2-3 pages to get a representative sample of the brand:

  1. Homepage (mandatory) — the primary brand expression
  2. Product/feature page (if available) — deeper color and layout usage
  3. Blog or about page (optional) — secondary design context

Use WebFetch on each URL with a prompt like:

"Extract the full content of this page. I need: all color values (hex, rgb, hsl), font family names, CSS class names (especially Tailwind utility classes), any CSS custom properties/variables, meta tags, and the general structure of the page layout. Preserve exact color codes and font names."

Phase 2: Extract Color Palette

Analyze the fetched content to identify the color palette. Look for these sources in priority order:

2.1 CSS Custom Properties

Look for :root, html, or body blocks containing color variables:

--color-primary, --primary, --brand, --accent
--bg-*, --background-*
--text-*, --foreground-*

2.2 Meta Tags

Check for:

  • <meta name="theme-color" content="#..."> — often the primary brand color
  • <meta name="msapplication-TileColor" content="#...">

2.3 Explicit CSS Color Declarations

Search for color values in these properties:

  • background-color, background (including gradients)
  • color (text colors)
  • border-color, border
  • box-shadow (accent/glow colors)
  • fill, stroke (SVG logo colors)

2.4 Tailwind Utility Classes

If the site uses Tailwind CSS, map utility classes to hex values using the reference table below.

2.5 Classify Colors into Roles

Role How to Identify
bg-primary background-color on body, html, or outermost container. The most common background.
bg-secondary Background on cards, sections, or secondary containers. Slightly different from primary.
text-primary color on body or the most common text color.
text-secondary Muted text variant — used on subtitles, descriptions, .text-gray-* elements.
accent Most prominent non-bg, non-text color. Found on buttons, links, CTAs, highlights. Also check <meta name="theme-color">.
accent-secondary Second accent color, or gradient partner. Found on secondary buttons, hover states.
card-bg Background of cards, modals, or elevated surfaces (if different from bg-primary).

2.6 Determine Theme Type

Check the luminance of bg-primary:

  • Dark theme: Dark background (black, navy, charcoal) with light text
  • Light theme: White or cream background with dark text
  • Mixed: Note if the site uses both (e.g., dark hero + light content sections)

Phase 3: Extract Typography

3.1 Find Font Sources

Look for font loading in this order:

  1. Google Fonts <link> tags — Font name is in the URL:

    fonts.googleapis.com/css2?family=Inter:wght@400;700
    

    → Font: Inter, weights: 400, 700

  2. Fontshare <link> tags — Similar URL pattern:

    api.fontshare.com/v2/css?f[]=clash-display@400,700
    

    → Font: Clash Display

  3. @font-face declarations — Extract the font-family value

  4. font-family CSS properties — Direct declarations on elements

3.2 Classify into Display vs Body

Role How to Identify
Display font Font on h1, h2, .title, .heading, .hero-title, or the largest/boldest text.
Body font Font on body, p, or general content elements.

If both use the same font family, it's a single-family pairing (like "Manrope + Manrope"). Note the different weights used for display (700-900) vs body (400-500).

3.3 Handle Proprietary Fonts

If the site uses a font NOT available on Google Fonts or Fontshare, map it to the closest available equivalent using the Font Fallback Table below.


Phase 4: Analyze Visual Patterns

Examine the CSS and page structure for these aesthetic signals:

Signal What to Look For Aesthetic Implication
Border radius border-radius values — large (12px+, 9999px) vs small (2-4px) vs none Rounded = friendly/modern. Sharp = corporate/bold.
Gradients linear-gradient, radial-gradient in backgrounds Gradient-forward = modern SaaS aesthetic
Shadows box-shadow frequency and intensity Heavy shadows = depth/elevation. None = flat/minimal.
Spacing Padding/margin sizes — generous (4rem+) vs tight (1rem) Airy = premium/minimal. Dense = information-rich.
Animations @keyframes, transition, transform presence Motion-forward = energetic. Minimal = calm/professional.
Grid patterns Background grid/dot patterns, decorative overlays Technical/developer aesthetic
Gradient orbs radial-gradient on positioned pseudo-elements Modern, atmospheric aesthetic
Borders as accents Colored border-left or border-top on sections Editorial, organized aesthetic

Synthesize the Vibe

Based on the signals above, compose:

  1. Vibe: 2-4 adjectives (e.g., "Clean, technical, developer-focused, modern")
  2. Layout description: 1 sentence (e.g., "Full-width dark sections with centered content and generous whitespace")
  3. Signature elements: 3-4 reproducible CSS patterns from the site

Phase 5: Generate Output

Create the file clients/<client-name>/brand/visual-identity.md with both output formats.

Output Template

# Visual Brand Identity: [Company Name]

**Extracted from:** [URL(s)]
**Date:** [YYYY-MM-DD]

---

## Slide Preset

**Vibe:** [2-4 adjectives]

**Layout:** [1 sentence describing dominant layout pattern]

**Typography:**
- Display: `[Font Name]` ([weight, e.g., 700/800])
- Body: `[Font Name]` ([weight, e.g., 400/500])

**Colors:**
```css
:root {
    --bg-primary: [hex];
    --bg-secondary: [hex];
    --text-primary: [hex];
    --text-secondary: [hex];
    --accent: [hex];
    --accent-secondary: [hex];
}
```

**Signature Elements:**
- [Element 1, e.g., "Subtle gradient orbs as background decoration"]
- [Element 2, e.g., "Rounded cards with 12px border-radius and light shadow"]
- [Element 3, e.g., "Accent-colored left border on feature blocks"]
- [Element 4, e.g., "Grid dot pattern overlay on hero sections"]

**Font Loading:**
```html
<link href="https://fonts.googleapis.com/css2?family=[Font1]:wght@[weights]&family=[Font2]:wght@[weights]&display=swap" rel="stylesheet">
```

---

## Brand Config (JSON)

For use with `content-asset-creator` and other skills:

```json
{
  "name": "[Company]",
  "primary_color": "[accent hex]",
  "secondary_color": "[accent-secondary hex]",
  "accent_color": "[accent hex]",
  "background": "[bg-primary hex]",
  "text_color": "[text-primary hex]",
  "font_heading": "[Display Font]",
  "font_body": "[Body Font]",
  "logo_url": "[if discovered, otherwise omit]"
}
```

---

## Extraction Notes

[Any notes about the extraction — proprietary fonts that were mapped, multiple themes detected, sparse CSS from JS-rendered sites, etc.]

Font Fallback Table

When a site uses a proprietary font not available on Google Fonts or Fontshare, use this mapping to find the closest available alternative:

Font Category Proprietary Examples Google Fonts Alternative Fontshare Alternative
Geometric sans Circular, Roobert, Graphik, Product Sans Plus Jakarta Sans, Outfit, Manrope General Sans, Satoshi
Humanist sans Proxima Nova, Calibri, Gill Sans Source Sans 3, DM Sans, Work Sans
Neo-grotesque Akkurat, Aktiv Grotesk, Suisse Int'l Space Grotesk, Archivo, Albert Sans Switzer
Modern serif Tiempos, Canela, GT Sectra Fraunces, Cormorant, Playfair Display Zodiak, Sentient
Slab serif Sentinel, Clarendon, Rockwell Zilla Slab, Roboto Slab
Classic serif Mercury, Chronicle, Minion Source Serif 4, Lora, Libre Baskerville Bespoke Serif
Monospace SF Mono, Berkeley Mono, Dank Mono JetBrains Mono, Fira Code, Space Mono Jet Brains Mono
Display / decorative GT Walsheim, Recoleta, Campton Syne, Archivo Black, Bricolage Grotesque Clash Display, Cabinet Grotesk

Decision heuristic: If unsure which category a font falls into, look at its characteristics:

  • Round dots and geometric 'o' → Geometric sans
  • Varies stroke widths, warm feel → Humanist sans
  • Uniform strokes, neutral → Neo-grotesque
  • Serifs with high contrast → Modern serif

Tailwind CSS Color Reference

If the site uses Tailwind utility classes, map them to hex values:

Grays

Class Hex Class Hex
gray-50 #F9FAFB gray-500 #6B7280
gray-100 #F3F4F6 gray-600 #4B5563
gray-200 #E5E7EB gray-700 #374151
gray-300 #D1D5DB gray-800 #1F2937
gray-400 #9CA3AF gray-900 #111827
gray-950 #030712

Slate (common for dark themes)

Class Hex Class Hex
slate-50 #F8FAFC slate-500 #64748B
slate-100 #F1F5F9 slate-600 #475569
slate-200 #E2E8F0 slate-700 #334155
slate-300 #CBD5E1 slate-800 #1E293B
slate-400 #94A3B8 slate-900 #0F172A
slate-950 #020617

Blues

Class Hex Class Hex
blue-400 #60A5FA blue-700 #1D4ED8
blue-500 #3B82F6 blue-800 #1E40AF
blue-600 #2563EB blue-900 #1E3A8A

Greens

Class Hex Class Hex
green-400 #4ADE80 green-600 #16A34A
green-500 #22C55E green-700 #15803D

Common Accent Colors

Class Hex Class Hex
indigo-500 #6366F1 purple-500 #A855F7
indigo-600 #4F46E5 violet-500 #8B5CF6
emerald-500 #10B981 amber-500 #F59E0B
teal-500 #14B8A6 rose-500 #F43F5E
cyan-500 #06B6D4 orange-500 #F97316

Note: Tailwind classes appear as bg-blue-600, text-gray-900, border-indigo-500, etc. Strip the property prefix (bg-, text-, border-) to get the color token, then look up the hex value above.

For custom Tailwind themes (e.g., bg-brand, text-brand-light), check the page's <script> tags for a tailwind.config object that defines custom colors.


Edge Cases

JS-Rendered Sites (Sparse CSS)

Many modern sites (Next.js, React) inject styles via JavaScript. WebFetch may return minimal inline CSS. In this case:

  • Focus on Tailwind utility classes in class attributes
  • Check <script> tags for embedded config objects
  • Look for <style> tags that contain CSS-in-JS output
  • If still sparse, ask the user: "The site appears to use dynamic styling. Could you share a screenshot or provide their brand guidelines directly?"

Multiple Color Schemes (Light/Dark Mode)

Some sites define both light and dark themes via prefers-color-scheme. Extract the default (non-media-query) theme. If a dark mode variant is detected, note it in the Extraction Notes section.

Too Many Colors

Enterprise sites may use dozens of colors. Focus on:

  • The hero/above-the-fold section for the primary palette
  • Button/CTA colors for accent identification
  • Frequency analysis — top 5-7 unique colors define the brand

No Usable Font Information

If font detection fails completely:

  1. Check if the site mentions font names in its CSS comments or config
  2. Look at the overall aesthetic and pick a matching pairing from the existing slide presets
  3. Default to a safe, distinctive pairing based on vibe: serif display + sans body for premium; geometric sans for modern tech

Example

Running this skill on https://vapi.ai might produce:

# Visual Brand Identity: Vapi

**Extracted from:** https://vapi.ai, https://docs.vapi.ai
**Date:** 2026-02-26

---

## Slide Preset

**Vibe:** Technical, developer-focused, clean, modern

**Layout:** Dark full-width sections with centered content, card-based feature grids, generous spacing

**Typography:**
- Display: `Inter` (700/800)
- Body: `Inter` (400/500)

**Colors:**
\```css
:root {
    --bg-primary: #0F172A;
    --bg-secondary: #1E293B;
    --text-primary: #F8FAFC;
    --text-secondary: #94A3B8;
    --accent: #22C55E;
    --accent-secondary: #3B82F6;
}
\```

**Signature Elements:**
- Subtle gradient orbs in background (green-to-blue radial gradients)
- Rounded cards with slate-800 background and subtle border
- Code-style monospace accents for technical terms
- Green accent on CTAs and interactive elements

**Font Loading:**
\```html
<link href="https://fonts.googleapis.com/css2?family=Inter:wght@400;500;700;800&display=swap" rel="stylesheet">
\```

(This is an illustrative example — actual extraction results will vary based on the live site.)


Tips

  • Homepage is usually enough. If the homepage has clear branding, you don't need additional pages. Fetch a second page only if the homepage is sparse or uses a different aesthetic from the rest of the site.
  • Buttons reveal the accent color. The most reliable way to identify the primary accent is to find the button/CTA background color.
  • Check the favicon/logo. SVG logos often contain the exact brand colors as fill values.
  • Don't over-extract. The goal is 5-7 colors, 1-2 fonts, and 3-4 signature elements. More than that creates noise, not signal.
  • When in doubt, simplify. A 3-color palette (bg + text + accent) with one font family at two weights makes a clean, usable preset.

Dependencies

  • Web fetch capability (for reading website pages)
  • No API keys or paid tools required
Weekly Installs
9
GitHub Stars
340
First Seen
Mar 14, 2026
Installed on
opencode8
gemini-cli8
antigravity8
github-copilot8
codex8
amp8