Permitted use of source code

I bought the Fancy Forms book and would like to use a lightly edited version of the CSS source code provided with the book on my own sites. I don’t see any statement about usage or any license, so can you tell me if it is permitted to

  1. Use the source code on a free site?
  2. Use the source code on a commercial site?
  3. Include the source code in my public GitHub repository?

And do you require attribution? Any specific format?