A gulp script with which you can the Critical Css of a web page. The script needs the url of page and the css file of it and gulp will do all the work! You can set a gulp task based on these already there.
To run the script, first you need to create a package.json: npm init
.
Later, install gulp and all his DevDependencies: npm install -g gulp
and npm install --save-dev gulp
.
And type gulp name_of_task
.
That's all!