<===> input.scss .code.ruby > { &.ruby { color: green; } } <===> error Error: Invalid parent selector for "&.ruby": ".code.ruby >" on line 2 of input.scss Use --trace for backtrace. <===> error-dart-sass Error: Parent ".code.ruby >" is incompatible with this selector. , 2 | &.ruby { | ^^^^^^^ ' input.scss 2:5 root stylesheet