In my app, I already have a sass structure/files created by an expert. I understand sass but don't have the expertise to solve this problem. I simply wanted to add flags to my app's CSS from here https://kfpun.com/flag-css/ where the author provides scss files. So I dropped the scss files to my directory next to other scss files and added the imports so that when I process my scss files, the necessary css would be included in the output. When I try to process them, I'm getting an error that looks like this: This is what it looks like in Visual Studio with the error when I hover over the line. What exactly is the problem and how do I fix it? Thanks.