update readme on diff code blocks

README.md

@@ -4,11 +4,11 @@
 
 [rehype] plugin to highlight code blocks in HTML with [Prism] (via [refractor]) with additional line highlighting and line numbers functionalities.
 
-Inspired by and uses a compatible API as [@mapbox/rehype-prism](https://github.com/mapbox/rehype-prism) with additional support for line-highlighting and line numbers.
+Inspired by and uses a compatible API as [@mapbox/rehype-prism](https://github.com/mapbox/rehype-prism) with additional support for line-highlighting, line numbers and diff code blocks.
 
 Tested to work with [xdm] and mdx v2 libraries such as [mdx-bundler]. If you are using mdx v1 libraries such as [next-mdx-remote], you will need to patch it with the `fixMetaPlugin` discussed in this [issue](https://github.com/timlrx/rehype-prism-plus/issues/20), before `rehype-prism-plus`.
 
-An [appropriate stylesheet](#styling) should be loaded to style the language tokens, format line numbers and highlight lines.
+An [appropriate stylesheet](#styling) should be loaded to style the language tokens, format line numbers and highlight lines. You can specify language for diff code blocks by using diff-[language] to enable syntax highlighting in diffs.
 
 ## Installation