When I try to install node-sass using npm, I get the following error message:
Cannot download \"https://github.com/sass/node-sass/releases/download/v3
You have an error on your command:
$ npm install node-sass --save-dev-
^^^
Should be
$ npm install node-sass --save-dev
(without the last - on dev)
Also, it is giving you a WARNING because it wants to be installed globally.
See the official node-sass documentation.
And also, could be interesting for you to know the differences between --save and --save-dev.