I have been given the task of validating that we do not have any http:// URLs in our CSS or HTML documents. I've created a selenium IDE test that looks at src & href attributes as well as script tags for http: but I'm not sure how to test a style sheet.
As I'm not trying to test specific selectors, it could be in any attribute in the document. For instance, a random div tags background:
I've thought about putting this in java and attempting to pull resources and parse them, but that seems a bit over the top.