Primer's CSS Guidelines suggests using // for comments

[RobLoach]

https://github.com/primer/primer/blob/master/docs/guidelines.md#formatting

Use // for comment blocks (instead of /* */).

Without a preprocessor, C-style // comments are invalid.

body {
  background-color: red;
}
// This is an invalid comment.

/* This is a valid comment. */

[jonrohan]

Thanks for the note, our "css" guidelines are meant to refer to scss files. I'm updating the section title to make it more clear #89

[RobLoach]

Thanks @jonrohan, I assumed as such. Just seemed strange to suggest that CSS use //. 👍