styles.css seems to not have correct header

[crakjie]

styles.css which look like to show in browser send a file size of 0 byte.
That not realy a problem because it's still copiable but it's unallow the link to be used in balise.

[abadi199]

@crakjie Thanks for reporting this. I believe that's how intentional because GitHub doesn't want people to link the CSS directly from their site since they're not CDN. So the right way to use the styles.css is by downloading the file and then link it from your own server.