Hey, thanks for the report. This is a known limitation of the CSS TextMate grammar that Cursor inherits from VS Code, and you can reproduce it there the same way. It’s not Cursor-specific, so we won’t ship a fix on our side. We’re waiting for an upstream fix.
Main tracking issue in VS Code: https://github.com/microsoft/vscode-css/issues/9. VS Code is currently experimenting with a tree-sitter CSS tokenizer that should fix this, and there’s also a community PR to update the grammar.