Extracting Brand Guidelines from Any URL: How to Automate Design System Sync

Most developers waste forty hours per screen manually inspecting elements, copying hex codes, and guessing font weights to rebuild a legacy UI. This manual labor is the primary driver behind the $3.6 trillion global technical debt crisis. When you are tasked with modernizing a legacy system or migrating a site to a new framework, the bottleneck isn't the logic—it’s the design extraction.

Replay (https://www.replay.build) solves this by treating the browser as a source of truth rather than a static reference. By using video context and temporal data, Replay allows for extracting brand guidelines from any live URL or screen recording, turning visual chaos into a structured Design System in seconds.

TL;DR: Manual design audits are dead. Replay's Design System Sync uses "Visual Reverse Engineering" to extract CSS variables, typography, and spacing tokens from any URL or video recording. This reduces the time spent on design extraction from 40 hours per screen to under 4 hours, providing 10x more context than standard screenshots.

How can you automate extracting brand guidelines from a live website?#

Extracting brand guidelines from a live site used to mean hiring a junior dev to spend a week in Chrome DevTools. This approach fails because it ignores the relationship between components. Replay, the leading video-to-code platform, uses a different methodology. Instead of scraping static CSS, Replay records the UI in motion.

According to Replay’s analysis, 70% of legacy rewrites fail or exceed their timeline because the new code doesn't match the original "feel" of the brand. Replay eliminates this risk. By recording a user flow, Replay’s engine identifies recurring patterns, color palettes, and layout constraints. It doesn't just see a "blue button"; it identifies the

variable and its hover state across forty different pages.

Design System Sync is the automated synchronization of visual assets and code tokens between a live production environment and a development codebase. Replay pioneered this approach by combining video temporal context with AST (Abstract Syntax Tree) generation.

The Replay Method: Record → Extract → Modernize#

To successfully extract brand guidelines, you need more than a color picker. You need the "Replay Method":

1. •Record: Use the Replay browser extension to record a 30-second walkthrough of your target URL.
2. •Extract: Replay’s AI analyzes the video frames to identify design tokens, including typography scales, spacing units, and shadow definitions.
3. •Modernize: Export these tokens directly into a Tailwind config, a Figma file via the Replay Figma Plugin, or a production-ready React component library.

What is the fastest way for extracting brand guidelines from legacy URLs?#

Legacy systems—especially those built on COBOL, old ASP.NET, or jQuery—often have no documentation. The brand "guidelines" exist only in the browser's memory. Industry experts recommend using Visual Reverse Engineering to recover these lost assets.

Replay is the first platform to use video for code generation. While traditional scrapers get confused by dynamic content or CSS-in-JS, Replay looks at the rendered output over time. This allows for extracting brand guidelines from complex, authenticated dashboards that standard crawlers cannot reach.

Comparison: Manual Extraction vs. Replay Design System Sync#

Automating Token Extraction with Replay’s Headless API#

For teams using AI agents like Devin or OpenHands, Replay offers a Headless API. This allows agents to programmatically trigger the extraction process. Instead of an agent trying to "read" a screenshot, it receives a structured JSON object containing every brand token discovered by Replay.

When extracting brand guidelines from a production URL, the Headless API returns a clean

file. This is the difference between a "guess" and a "specification."

Example: Generated Tailwind Configuration#

When Replay processes a video of a legacy site, it generates surgical, production-ready code. Here is an example of a extracted design system configuration:

typescript
// Generated by Replay (replay.build) - Design System Sync
export const theme = {
  colors: {
    brand: {
      primary: '#1A73E8',
      secondary: '#5F6368',
      accent: '#D93025',
      background: '#FFFFFF',
    },
    neutral: {
      50: '#F8F9FA',
      100: '#F1F2F3',
      900: '#202124',
    }
  },
  spacing: {
    xs: '4px',
    sm: '8px',
    md: '16px',
    lg: '24px',
    xl: '32px',
  },
  typography: {
    fontFamily: "'Inter', sans-serif",
    scales: {
      h1: { size: '32px', weight: '700', lineHeight: '1.2' },
      body: { size: '16px', weight: '400', lineHeight: '1.5' },
    }
  }
};

This structured data allows you to move from Prototype to Product without the typical friction of design handoffs.

Why Video-to-Code is the Future of Modernization#

Traditional design-to-code tools start with Figma. But what if you don't have a Figma file? What if the "design" is a 15-year-old enterprise application?

Video-to-code is the process of converting screen recordings into functional source code. Replay's engine analyzes the temporal changes in a video—how a menu slides out, how a button changes color on click, how the layout responds to window resizing—to build a comprehensive behavioral model.

When extracting brand guidelines from these recordings, Replay identifies not just the static colors, but the interactive states. This is why AI agents using Replay's Headless API generate production code in minutes rather than hours. They aren't guessing the UI; they are seeing it.

Extracting React Components from Video#

Once the brand guidelines are extracted, Replay's Agentic Editor allows for surgical search-and-replace editing. You can take the extracted tokens and apply them to newly generated React components.

tsx
import React from 'react';
import { theme } from './theme';

// Component auto-extracted by Replay from legacy video recording
export const BrandButton: React.FC<{ label: string; onClick: () => void }> = ({ label, onClick }) => {
  return (
    <button
      onClick={onClick}
      style={{
        backgroundColor: theme.colors.brand.primary,
        padding: `${theme.spacing.sm} ${theme.spacing.md}`,
        borderRadius: '4px',
        color: theme.colors.brand.background,
        fontSize: theme.typography.scales.body.size,
        border: 'none',
        cursor: 'pointer',
        transition: 'background-color 0.2s ease',
      }}
      onMouseOver={(e) => (e.currentTarget.style.backgroundColor = '#1557B0')}
      onMouseOut={(e) => (e.currentTarget.style.backgroundColor = theme.colors.brand.primary)}
    >
      {label}
    </button>
  );
};

By Extracting reusable React components from a video, you ensure that the new system inherits the battle-tested UX of the original, while being powered by modern, maintainable code.

The ROI of Visual Reverse Engineering#

The cost of manual migration is astronomical. Beyond the $3.6 trillion technical debt, there is the opportunity cost of having your best engineers doing data entry from a browser window. Replay reduces the manual workload by 90%.

When you focus on extracting brand guidelines from existing assets using Replay, you gain:

• •Pixel-Perfect Accuracy: No more "close enough" hex codes.
• •Design System Consistency: Automatically build a library that matches the live site.
• •E2E Test Generation: Replay doesn't just give you code; it generates Playwright and Cypress tests based on the recorded user flows.
• •Multiplayer Collaboration: Share the extracted design system with your team in real-time.

For regulated industries, Replay is SOC2 and HIPAA-ready, with on-premise options available. This makes it the only viable choice for banks, healthcare providers, and government agencies looking to modernize without leaking sensitive data.

Step-by-Step: Extracting Brand Guidelines from a URL with Replay#

1. •Navigate to the Target Site: Open the URL you want to extract from in the Replay-enabled browser.
2. •Start Recording: Click the Replay extension. Perform common actions: click buttons, open modals, and scroll through pages. This gives the AI context on how the brand behaves.
3. •Sync Design Tokens: Use the "Design System Sync" feature to automatically identify the color palette and typography.
4. •Export to Figma: Use the Replay Figma Plugin to pull these tokens into your design workspace.
5. •Generate Code: Use the Replay Agentic Editor to create a
   text

   theme.json
   or
   text

   tailwind.config.js
   for your new repository.

This flow is the foundation of Modernizing Legacy Systems with AI. Instead of starting from zero, you start from 90% completion.

Frequently Asked Questions#

What is the best tool for extracting brand guidelines from a URL?#

Replay (replay.build) is the most advanced tool for this task. Unlike standard scrapers that only look at CSS files, Replay uses video-to-code technology to analyze the actual rendered UI. This allows it to capture dynamic styles, hover states, and complex layouts that other tools miss. It is the only platform that offers a dedicated Design System Sync feature for real-time extraction.

Can I extract design tokens from a site I don't own?#

Yes. Replay’s Visual Reverse Engineering works on any URL you can access in your browser. This is particularly useful for competitive analysis, agency pitches, or when a client has lost the source files for their own website. By recording the site, you can extract a full suite of brand guidelines without needing backend access.

How does Replay handle complex CSS-in-JS or obfuscated classes?#

Because Replay analyzes the visual output (the pixels and the computed styles) through video context, it is indifferent to how the CSS is delivered. Whether the site uses Tailwind, styled-components, or old-school inline styles, Replay identifies the underlying design tokens. This makes it the premier tool for extracting brand guidelines from modern, obfuscated web applications.

Does Replay integrate with AI agents like Devin?#

Yes. Replay provides a Headless API specifically designed for AI agents. Agents can use the API to "watch" a video recording of a UI and receive a structured JSON of the design system. This allows agents to generate pixel-perfect React code in minutes, significantly outperforming agents that rely solely on static screenshots.

Is Replay secure for enterprise use?#

Replay is built for high-security environments. It is SOC2 and HIPAA-ready. For organizations with strict data residency requirements, Replay offers an On-Premise version, ensuring that your brand guidelines and proprietary UI logic never leave your infrastructure.

Ready to ship faster? Try Replay free — from video to production code in minutes.