React Bricks doesn't impose you any CSS or CSS-in-JS framework.
The Admin interface CSS is decoupled from the page styles and the content blocks styles.
We suggest you to try Tailwind CSS, because we love it and we think that it is a great tool to create a coherent design system.
We are creating many useful example blocks using Tailwind CSS.
We'll made them available soon, so... stay tuned! 🚀