$ sudo npm install grunt-contrib-cssmin
$ sudo npm install -g grunt-contrib-cssmin

If want to update the grunt-contrib-cssmin package execute the command as below,

$ sudo npm update grunt-contrib-cssmin

Update package globally,

$ npm install -g grunt-contrib-cssmin

Git clone:

$ sudo  git clone https://github.com/rektide/grunt-contrib-cssmin.git

$ sudo  npm install -g ./grunt-contrib-cssmin

grunt-contrib-cssmin@2.2.1 /usr/lib/node_modules/grunt-contrib-cssmin

How to remove grunt-contrib-cssmin package :

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

$ sudo npm uninstall grunt-contrib-cssmin

Basic Information of grunt-contrib-cssmin NPM Package: