How to add npm .css file to Grunt?

Question

I am using Grunt to compile my SASS files. Now I need to add animate.css from npm, so I added it with:

$ npm install animate.css --save

But how do I add it to Grunt? I thought, that changing the "sass" configuration by adding "node_modules/animate.css/animate.css" to the array would be enough:

sass: {
            dist: {
                options: {
                    style: "compressed",
                    compass: false
                },
                files: {
                    "dist/main.css": ["scss/main.scss", "node_modules/animate.css/animate.css"]
                }
            }
        },

Unfortunately, this doesn't work.

My main.scss file, is just a file sitting next to node_modules directory, so what I could do, is to rename node_modules/animate.css/animate.css into _animate.scss and then @import it in my main.scss, but this seems to be not the proper way of adding styles. This would mean, that every time I need some external styles, I would have to rename them to .scss

This seems to be such a basic thing to do, to import styles from npm, yet I cannot find information about it.