CSS Modules vs Stitches: What are the differences?

# Introduction
CSS Modules and Stitches are two popular styling solutions in the world of web development. While they both aim to provide better styling organization and scoping, they have key differences that set them apart.

1. **Global vs Local Scope**: CSS Modules generate unique class names at build time, ensuring styles are locally scoped to avoid naming collisions. In contrast, Stitches uses a single, global stylesheet with atomic styles that are applied dynamically at runtime, offering a more global styling approach.
  
2. **Runtime vs Build Time**: Stitches applies styles dynamically at runtime, allowing for more flexibility and faster updates without the need to rebuild the entire application. On the other hand, CSS Modules generate static CSS files at build time, which can improve performance but may require a rebuild for every style update.
  
3. **API vs Webpack Plugin**: Stitches provides an API for defining styles, breakpoints, and themes programmatically, offering more control and flexibility over the styling process. CSS Modules, on the other hand, require a separate Webpack plugin to handle the scoping and transforming of class names in the CSS files.

4. **Composition Capability**: Stitches excels in the composition of styles by allowing developers to combine style utilities easily, creating a more efficient and reusable styling system. CSS Modules, while offering modularity, may require more effort to achieve the same level of composition.

5. **Bundle Size**: Stitches generates highly optimized CSS outputs tailored to the specific components used in the application, potentially reducing the overall bundle size by eliminating unused styles. In comparison, CSS Modules create separate CSS files for each module, which may lead to larger bundle sizes depending on the number of modules and styles used.

6. **Community and Ecosystem**: CSS Modules have been around longer and have a more extensive community and ecosystem of tools and resources available for developers. Stitches, being a newer solution, is rapidly growing but may have a smaller community and fewer integrations compared to CSS Modules.

In Summary, CSS Modules and Stitches offer distinct approaches to styling in web development, with differences in scope isolation, styling application, API usage, composition capabilities, bundle size optimization, and community support and ecosystem size.