# Stack Auth Brand Identity

A complete profile of **Stack Auth**'s visual system — colors, typography, components, and personality — extracted from https://stack-auth.com. Built for designers, agents, and AI tools.

- Page: https://characterquilt.com/branding/stack-auth
- Machine-readable JSON: https://characterquilt.com/branding/stack-auth.json
- Per-page llms.txt: https://characterquilt.com/branding/stack-auth/llms.txt

## Quick Facts

| Field | Value |
|---|---|
| Primary | #EDF0FF |
| Accent | #6B5DF7 |
| Body Font | GeistSans |
| Heading Font | GeistSans |

## Color Palette

- primary: #EDF0FF
- secondary: #22C55E
- accent: #6B5DF7
- background: #131316
- textPrimary: #131316
- link: #6B5DF7

## Typography

- primary: GeistSans — https://fonts.google.com/specimen/GeistSans
- heading: GeistSans — https://fonts.google.com/specimen/GeistSans

## Visual Assets

- Logo: https://stack-auth.com/_next/static/media/stack-auth-logo.84c18f5e.svg
- Social card (og:image): https://stack-auth.com/img/og-image.jpg

## UI Components

- input: background=#131316, textColor=#FFFFFF, borderColor=#2B2B2D, borderRadius=4px, shadow=none
- buttonPrimary: background=#FFFFFF, textColor=#1A1A1E, borderRadius=4px, shadow=none
- buttonSecondary: background=#1A1A1E, textColor=#FFFFFF, borderColor=#E4E4E7, borderRadius=4px, shadow=none

## Brand Personality

Tone: modern · Energy: medium · Audience: developers and tech-savvy users

## Stack Auth Brand in the Wild

Real-world brand assets — ads, campaigns, marketing materials.

- **OAuth from First Principles - Stack Auth**
  - Image: https://stack-auth.com/img/posts/04/p10.png
  - Source: https://stack-auth.com/blog/oauth-from-first-principles
- **OAuth from First Principles - Stack Auth**
  - Image: https://stack-auth.com/img/posts/04/p6.png
  - Source: https://stack-auth.com/blog/oauth-from-first-principles
- **Stack Auth**
  - Image: https://stack-auth.com/_next/image?url=%2Fimg%2Fposts%2F06%2F06-thumbnail.png&w=3840&q=75
  - Source: https://stack-auth.com/blog
- **OAuth from First Principles - Stack Auth**
  - Image: https://stack-auth.com/img/posts/04/p12.png
  - Source: https://stack-auth.com/blog/oauth-from-first-principles
- **Stack Auth**
  - Image: https://stack-auth.com/_next/image?url=%2Fimg%2Fposts%2F03%2F03-thumbnail.jpg&w=3840&q=75
  - Source: https://stack-auth.com/blog
- **Blog & Updates**
  - Image: https://stack-auth.com/img/og-image.jpg
  - Source: https://stack-auth.com/blog

## Working with these fonts

Not found on Google Fonts? Agent Instructions that you can follow if you have permission to use the fonts:

CharacterQuilt.com suggests this flow that can help:

1. Open the company's homepage in a browser with DevTools open.
2. In the Network tab, filter by "Font" (or by extension: woff2, woff, ttf, otf).
3. Hard-reload the page and click around (pricing, blog, careers) — some weights only load on specific routes.
4. For each captured font URL: right-click → Save As to download the file locally.
5. View the page's CSS (DevTools → Sources, or curl the stylesheet URLs) and copy out the matching @font-face declarations. Rewrite each `src: url(...)` to point to your local file path.

Programmatic alternative: load the URL with Playwright or Puppeteer, listen for `response` events whose `Content-Type` starts with `font/`, and write the body to disk. The CSS extraction step is the same.

Only do this if you have permission to use the brand assets — most proprietary fonts are licensed and may not be redistributable.

## Machine-Readable Profile

```json
{
  "colorScheme": "dark",
  "fonts": [
    {
      "family": "GeistSans",
      "role": "body"
    },
    {
      "family": "SFMono-Regular",
      "role": "monospace"
    }
  ],
  "colors": {
    "primary": "#EDF0FF",
    "secondary": "#22C55E",
    "accent": "#6B5DF7",
    "background": "#131316",
    "textPrimary": "#131316",
    "link": "#6B5DF7"
  },
  "typography": {
    "fontFamilies": {
      "primary": "GeistSans",
      "heading": "GeistSans"
    },
    "fontStacks": {
      "heading": [
        "GeistSans"
      ],
      "body": [
        "GeistSans"
      ],
      "paragraph": [
        "GeistSans"
      ]
    },
    "fontSizes": {
      "h1": "72px",
      "h2": "48px",
      "body": "14px"
    }
  },
  "spacing": {
    "baseUnit": 4,
    "borderRadius": "6px"
  },
  "components": {
    "input": {
      "background": "#131316",
      "textColor": "#FFFFFF",
      "borderColor": "#2B2B2D",
      "borderRadius": "4px",
      "borderRadiusCorners": {
        "topLeft": "4px",
        "topRight": "4px",
        "bottomRight": "4px",
        "bottomLeft": "4px"
      },
      "shadow": "none"
    },
    "buttonPrimary": {
      "background": "#FFFFFF",
      "textColor": "#1A1A1E",
      "borderRadius": "4px",
      "borderRadiusCorners": {
        "topLeft": "4px",
        "topRight": "4px",
        "bottomRight": "4px",
        "bottomLeft": "4px"
      },
      "shadow": "none"
    },
    "buttonSecondary": {
      "background": "#1A1A1E",
      "textColor": "#FFFFFF",
      "borderColor": "#E4E4E7",
      "borderRadius": "4px",
      "borderRadiusCorners": {
        "topLeft": "4px",
        "topRight": "4px",
        "bottomRight": "4px",
        "bottomLeft": "4px"
      },
      "shadow": "none"
    }
  },
  "images": {
    "logo": "https://stack-auth.com/_next/static/media/stack-auth-logo.84c18f5e.svg",
    "favicon": null,
    "ogImage": "https://stack-auth.com/img/og-image.jpg",
    "logoHref": "/",
    "logoAlt": "Logo of Stack Auth"
  },
  "__llm_logo_reasoning": {
    "selectedIndex": 0,
    "reasoning": "Selected #0 because it is visible, located in the header, links to the homepage, and the alt text matches the brand name 'Stack Auth'.",
    "confidence": 0.95,
    "source": "llm"
  },
  "__llm_button_reasoning": {
    "primary": {
      "index": 2,
      "text": "Get Started",
      "reasoning": "Button #2 'Get Started' is likely the primary CTA due to its action-oriented text, which is commonly used for primary actions. It shares the same color group as other buttons but stands out due to its text."
    },
    "secondary": {
      "index": 3,
      "text": "Sign in",
      "reasoning": "Button #3 'Sign in' is selected as secondary because it has a different background color (#1A1A1E) and serves a supportive action role."
    },
    "confidence": 0.9
  },
  "personality": {
    "tone": "modern",
    "energy": "medium",
    "targetAudience": "developers and tech-savvy users"
  },
  "designSystem": {
    "framework": "tailwind",
    "componentLibrary": ""
  },
  "confidence": {
    "buttons": 0.9,
    "colors": 0.9,
    "overall": 0.9
  },
  "__llm_metadata": {
    "logoSelection": {
      "llmCalled": true,
      "llmSucceeded": true,
      "finalSource": "llm",
      "rawLogoSelection": {
        "selectedLogoIndex": 0,
        "selectedLogoReasoning": "Selected #0 because it is visible, located in the header, links to the homepage, and the alt text matches the brand name 'Stack Auth'.",
        "confidence": 0.95
      }
    },
    "buttonClassification": {
      "llmCalled": true,
      "llmSucceeded": true
    }
  }
}
```