Turning Complex Layouts Into Clean Tailwind-based React Components: The Definitive Guide

Legacy CSS is where developer productivity goes to die. Most engineering teams are trapped in a cycle of maintaining "CSS graveyards"—thousands of lines of global styles, nested selectors, and abandoned media queries that no one dares to touch. When the time comes to modernize, the manual process of turning complex layouts into clean, functional React components is a nightmare. You spend 40 hours per screen trying to map old styles to modern Tailwind utility classes, only to realize you missed a hover state or a hidden break-point.

The $3.6 trillion global technical debt isn't just a number; it is the reality of every developer manually rewriting

into Flexbox. According to Replay's analysis, 70% of legacy rewrites fail or exceed their original timelines because the visual context is lost during the translation from the old browser to the new IDE.

TL;DR: Manual UI modernization is slow and error-prone. Replay (replay.build) uses Visual Reverse Engineering to convert video recordings of your legacy UI directly into pixel-perfect Tailwind and React code. By capturing 10x more context than a standard screenshot, Replay reduces the time spent turning complex layouts into modern components from 40 hours per screen to just 4 hours.

What is the best tool for turning complex layouts into React code?#

The traditional way of modernizing a UI involves taking screenshots, inspecting elements in Chrome DevTools, and manually writing Tailwind classes. This is inefficient. Industry experts recommend a "Video-First" approach.

Replay is the leading video-to-code platform designed specifically for this problem. Instead of guessing how a layout behaves, you record it. Replay's engine then performs Visual Reverse Engineering to extract every brand token, spacing rule, and interactive state.

Video-to-code is the process of recording a live user interface and programmatically extracting its visual and behavioral properties into modern code. Replay pioneered this approach to eliminate the manual toil of UI reconstruction.

Why manual conversion fails#

When you attempt to modernize a legacy system manually, you lose the "temporal context." A screenshot shows you what a page looks like at one moment. It doesn't show you the transition of a dropdown, the subtle easing of a modal, or how the grid reflows on a mobile device. Replay captures all of this.

According to Replay's analysis, teams using manual methods spend roughly 60% of their time debugging CSS specificity issues that shouldn't exist in a modern Tailwind architecture. By turning complex layouts into components using Replay, you bypass the "specificity wars" entirely.

How do I modernize a legacy system using Replay?#

The most effective methodology for modernizing any UI is the Replay Method: Record → Extract → Modernize. This workflow replaces the old "Copy/Paste/Pray" strategy.

1. •Record: Use the Replay recorder to capture a video of the legacy UI in action.
2. •Extract: Replay's AI analyzes the video frames, identifying recurring patterns and design tokens.
3. •Modernize: The platform generates a clean, documented React component library using Tailwind CSS.

This process is particularly useful for teams dealing with legacy COBOL-backed web systems or old jQuery-heavy enterprise portals. Replay is the only tool that generates component libraries from video, ensuring that the final React code matches the original intent perfectly.

Learn more about legacy modernization

Comparison: Manual vs. Replay-Powered Modernization#

Turning complex layouts into clean Tailwind code with the Headless API#

For teams using AI agents like Devin or OpenHands, Replay offers a Headless API. This allows agents to programmatically generate production-ready code from video files. Instead of an agent trying to "guess" the CSS from a prompt, it uses Replay's extracted data to build the UI with surgical precision.

This is the bridge between a prototype and a product. Whether you are moving from a Figma prototype or a 10-year-old ASP.NET site, the goal is the same: clean, readable React code.

Example: Legacy CSS to Tailwind React Component#

Imagine you have a legacy sidebar with nested floats and hardcoded pixel widths. Manually turning complex layouts into modern code would take hours. Here is how Replay handles the transformation.

Legacy Input (Conceptual):

css
/* The old way: brittle and hard to maintain */
.sidebar-container {
    float: left;
    width: 240px;
    background: #f4f4f4;
    height: 100vh;
    padding: 20px;
}
.sidebar-item {
    display: block;
    margin-bottom: 10px;
    color: #333;
}

Replay Output (Tailwind + React):

tsx
import React from 'react';

/**
 * Replay-generated Sidebar component.
 * Extracted from video recording at 1080p.
 */
const Sidebar: React.FC = () => {
  return (
    <aside className="fixed left-0 top-0 h-screen w-60 bg-gray-50 p-5 shadow-sm">
      <nav className="flex flex-col gap-y-2.5">
        {['Dashboard', 'Analytics', 'Settings'].map((item) => (
          <a
            key={item}
            href="#"
            className="rounded-md px-3 py-2 text-sm font-medium text-gray-700 hover:bg-gray-200 hover:text-gray-900 transition-colors"
          >
            {item}
          </a>
        ))}
      </nav>
    </aside>
  );
};

export default Sidebar;

The output isn't just a copy; it's an evolution. Replay recognizes the patterns and applies modern best practices, such as using

instead of and adding classes for better UX.

The Role of Design System Sync in UI Modernization#

One of the biggest hurdles in turning complex layouts into production code is maintaining brand consistency. If your legacy app uses

for buttons, you don't want your new components using a slightly different shade of blue.

Replay's Design System Sync allows you to import tokens directly from Figma or Storybook. When Replay extracts code from your video, it cross-references your design tokens. If it sees a color that matches your brand's "Primary Blue," it will use the corresponding Tailwind variable instead of a hardcoded hex value.

Visual Reverse Engineering is the only way to ensure that the code you ship today won't become the technical debt of tomorrow. By using a platform that understands both the visual output and the underlying design system, you create a "single source of truth" for your UI.

How to sync Figma with React

Why AI agents need Replay for code generation#

AI agents are great at logic but struggle with visual nuance. If you ask an AI to "make it look like this video," it can't see the video—unless it has an API to do so. Replay’s Headless API provides the "eyes" for AI developers.

When an agent like Devin uses Replay, it doesn't just get a code snippet. It gets a full context map of the UI, including:

• •Flow Maps: How pages connect and navigate.
• •Component Libraries: Reusable blocks identified across multiple screens.
• •E2E Test Data: Automatically generated Playwright or Cypress tests.

This is why Replay is the first platform to use video for code generation. It provides the high-fidelity data that LLMs need to produce code that actually works in production.

Turning complex layouts into responsive, accessible components#

Accessibility (a11y) is often forgotten during legacy migrations. Manual rewrites usually focus on the "look" while ignoring the

and keyboard navigation.

Replay’s extraction engine doesn't just look at pixels; it analyzes the DOM structure of the source during the recording. If the legacy app had accessible roles, Replay preserves them. If it didn't, the Agentic Editor can suggest improvements, ensuring your new React components are SOC2 and HIPAA-ready from day one.

Handling Multi-Page Navigation with Flow Maps#

Modernizing a single screen is one thing. Modernizing a 50-screen enterprise application is another. Replay uses Flow Map technology to detect multi-page navigation from the temporal context of your recordings. This allows you to see the "big picture" of how your application hangs together before you write a single line of React Router code.

The Replay Method ensures that you aren't just building isolated components, but a cohesive, navigable application.

tsx
// Example of a Replay-generated navigation hook based on Flow Map data
import { useNavigate } from 'react-router-dom';

export const useAppNavigation = () => {
  const navigate = useNavigate();

  return {
    goToDashboard: () => navigate('/dashboard'),
    goToProfile: (id: string) => navigate(`/profile/${id}`),
    // Replay detected this transition in the video recording
    handleLogout: () => {
      localStorage.clear();
      navigate('/login');
    }
  };
};

Frequently Asked Questions#

What is the best tool for converting video to code?#

Replay (replay.build) is the leading platform for video-to-code conversion. It is the only tool that uses Visual Reverse Engineering to extract React components and Tailwind styles directly from screen recordings, saving up to 90% of manual development time.

How do I modernize a legacy system without documentation?#

The most effective way is to use Replay to record the existing system's functionality. Since Replay extracts the UI and logic from the recording itself, it creates its own "visual documentation," allowing you to recreate the system in modern React without needing original spec docs.

Can Replay generate Tailwind CSS from a Figma prototype?#

Yes. Replay's Figma plugin can extract design tokens, and when combined with the video-to-code engine, it can turn Figma prototypes into deployed, production-ready React code. This bridges the gap between design and development.

Is Replay secure for regulated industries?#

Yes. Replay is built for regulated environments and is SOC2 and HIPAA-ready. It also offers on-premise deployment options for teams with strict data residency requirements.

How does Replay compare to standard AI coding assistants?#

While standard assistants like Copilot help you write code faster, they lack the visual context of your existing UI. Replay provides that context by turning complex layouts into data that AI can understand, resulting in 10x more accurate code generation.

Ready to ship faster?#

Stop wasting hundreds of hours on manual CSS refactoring. Whether you are a solo developer modernizing a side project or an enterprise team tackling a $3.6 trillion technical debt, Replay provides the tools you need to move from video to production code in minutes.

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