Bug Report: Nested CSS selectors with a& group produce broken output

Bug Report: Nested CSS selectors with a& group produce broken output: a task in LegoFlow-SWE (Harbor dataset). Description: When using Emotion 11’s css or styled APIs with nested selectors, selectors that place & at the end (e.g., a& ) are incorrectly transformed if they appear in a selector group…

The task

**Description:** When using Emotion 11’s `css` or `styled` APIs with nested selectors, selectors that place `&` at the end (e.g., `a&`) are incorrectly transformed if they appear in a selector group alongside pseudoclasses. This leads to malformed CSS output.

Part of Lego-X/LegoFlow-SWE.