In my career, responsive web design and dynamic user interfaces have evolved to be the norm, and CSS has kept up with demands.

Modern CSS features, such as Flexbox and Grid, have simplified complex layouts, allowing for responsive designs with less code. CSS variables have enabled better maintainability and reusability of styles.

Preprocessors like Sass and Less, emerged to extend CSS, though a lot of their features are now part of the CSS spec. PostCSS and its plugins further enhance CSS by allowing me to use future CSS syntax early.

CSS-in-JS libraries, such as styled-components and Emotion, allow managing styles in React applications, providing scoped styles, dynamic theming, and co-location of styles, though I have found some performance issues with this approach at times.

CSS Modules is currently my preferred approach when working with CSS in React, and in frameworks like Next.