You can install this plugin via the Packages manager in Atom itself or manually through the terminal
$ apm install csslint
CSSLint is by default validating on save (this can be changed in the package settings), you can also execute it by hitting
If you like you can even set it to validate while typing in the package settings.
fold modeby default (toggle in settings)
MIT © tcarlsen
Good catch. Let us know what about this package looks wrong to you, and we'll investigate right away.