Hello. Im using the MDB-Gulp-Free_4.19.1 version of MDB and I've got the problem with using @extend in scss. Please help me to properly use it.

Expected behavior Trying to apply bootstrap class styles to my class in _custom-styles.scss (code example below)

Actual behavior Terminal outputs: "failed to @extend ".w-100". The selector ".w-100" was not found."

Resources (screenshots, code snippets etc.) .class {@extend .w-100;@extend .d-sm-none;}