Css file is missing

[amygrimaldi]

After cloning the repository and installing all dependencies according to the instructions, /css/ionic.app.css was missing.
I took the file from the demo, but maybe there was some other way to have this file in the project.
In case it matters, the installation did not go smoothly because i got the following error:

There is an error in your gulpfile:
Error: libsass bindings not found. Try reinstalling node-sass?

I solved it by uninstalling and reinstalling gulp-sass.