Fullstack dev server Hot reloading HTML & static sites Standalone HTML CSS Loaders Single-file executable Plugins Macros Bytecode Caching Minifier esbuild

CSS

Bun's bundler has built-in support for CSS with modern features

Standalone HTML

Bundle a single-page app into a single self-contained .html file with no external dependencies

Loaders

Built-in loaders for the Bun bundler and runtime

On this page

Transpiling Browser Compatibility Syntax Lowering Nesting Color mix Relative colors LAB colors Color function HWB colors Color notation light-dark() color function Logical properties :dir() selector :lang() selector :is() selector :not() selector Math functions Media query ranges Shorthands Double position gradients system-ui font CSS Modules Getting started Composition Composing from a separate CSS module file