docs: Update reference to Stylo (#691)

README.md

@@ -9,7 +9,7 @@ An extremely fast CSS parser, transformer, and minifier written in Rust. Use it
 
 - **Extremely fast** – Parsing and minifying large files is completed in milliseconds, often with significantly smaller output than other tools. See [benchmarks](#benchmarks) below.
 - **Typed property values** – many other CSS parsers treat property values as an untyped series of tokens. This means that each transformer that wants to do something with these values must interpret them itself, leading to duplicate work and inconsistencies. Lightning CSS parses all values using the grammar from the CSS specification, and exposes a specific value type for each property.
-- **Browser-grade parser** – Lightning CSS is built on the [cssparser](https://github.com/servo/rust-cssparser) and [selectors](https://github.com/servo/servo/tree/master/components/selectors) crates created by Mozilla and used by Firefox and Servo. These provide a solid general purpose CSS-parsing foundation on top of which Lightning CSS implements support for all specific CSS rules and properties.
+- **Browser-grade parser** – Lightning CSS is built on the [cssparser](https://github.com/servo/rust-cssparser) and [selectors](https://github.com/servo/stylo/tree/main/selectors) crates created by Mozilla and used by Firefox and Servo. These provide a solid general purpose CSS-parsing foundation on top of which Lightning CSS implements support for all specific CSS rules and properties.
 - **Minification** – One of the main purposes of Lightning CSS is to minify CSS to make it smaller. This includes many optimizations including:
   - Combining longhand properties into shorthands where possible.
   - Merging adjacent rules with the same selectors or declarations when it is safe to do so.