I use 1.3 and React, many React packages on NPM have their own CSS files. Usually they will be somewhere in the node_modules directory (for example package/dist/css/). It’s not the biggest problem, you can just copy them to a directory outside node_modules and Meteor will be able to detect them.
It will straight forward crash Meteor. I have asked the author of the package and I’ve got this response:
But if you use webpack or browserify to build your app. There are css loader plugins to handle this special kind of require. (…) I never use Meteor before. I think maybe there’s some css require plugin in Meteor too.
and in the meantime, suggested solution is symlinking to that file from somewhere else in your app that is outside the node_modules directory so that Meteor can pick it up.
As @serkandurusoy mentions symlinking works fine and is what we are using right now. Also, this PostCSS package looks to be a nice solution available right now.
In Meteor 1.3 you can require css files in JS, they will be attached to the <head> for now, but I gues this will not work in this case and I wonder if this will work when you want to require from node_modules at all. We need to wait for Meteor 1.3.1 (I hope).