main.scss in assets

Hi,

I've tried to build your so-simple-theme because I quite like it :)
but when pushing to github i keep getting this buiild failure:

The page build failed with the following error:

The file `so-simple-theme/assets/css/main.scss` contains syntax errors. For more information, see https://help.github.com/articles/page-build-failed-markdown-errors.

I have no idea what I'm doing wrong :(
any clues?

thanks,
theresa