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What are some of your tips for organizing huge CSS projects?
I'll plug my Sass framework Eyeglass here. It allows you to distribute Sass files and related assets as npm modules. At my work we use this to distribute re-usable parts of our style like our theming system to many applications.
Lots of people like to have a
variables file and
partials directories. I'm really not a fan of this approach. Keep related code together and minimize bouncing around from file to file.
To that end, within an application, I suggest organization by product and feature with cross cutting theme or design language shared by all of those.