$ sudo npm install postcss-modules
$ sudo npm install -g postcss-modules

If want to update the postcss-modules package execute the command as below,

$ sudo npm update postcss-modules

Update package globally,

$ npm install -g postcss-modules

Git clone:

$ sudo  git clone https://github.com/rektide/postcss-modules.git

$ sudo  npm install -g ./postcss-modules

postcss-modules@1.1.0 /usr/lib/node_modules/postcss-modules

How to remove postcss-modules package :

You can uninstall or remove this package from your node_modules run the command as below,

$ sudo npm uninstall postcss-modules

Basic Information of postcss-modules NPM Package: