What does it do?
The holmes.css file will display either an error (red outline), a warning (yellow outline), or a deprecated style (dark grey outline) for flags such as:
- Missing required attributes on tags, such as name attributes on inputs (lots of these)
- Potentially improvable markup, such as links with href="#"
- Deprecated and Non-W3C Elements – see W3C.org’s article on obselete tags
- Non-W3C Attributes – as above, just the most important ones since there are MANY
