
The point is that although HTML and CSS have quite different escape mechanisms,
you can escape a character in both languages and have it interpreted the same way. You
can also escape a character in one of the languages and use it as such in the other.
If your CSS code is embedded inside an HTML document, it is better to use CSS escapes
rather than HTML escapes. One reason for this is that the latter are not always recog-
nized:
• In a style attribute, as in <p style="font-family: Lübeck">, HTML escapes are
recognized. You could write Lübeck or Lübeck there, but the CSS escaped
form L\fc beck works, too.
• In a style element, as in <style type="text/css">p { font-family: Lübeck }</
style>, HTML escapes are not recognized according to HTML specifications up
to and including HTML 4.01. The CSS escapes work, of course. (In XHTML, the
processing of the content of style elements has been defined differently, so that
HTML escapes are recognized.)
Identifiers in CSS
The HTML specifications do not prescribe the syntax of class names. It is left to style-
sheet languages, and CSS is rather permissive. You don’t often see non-ASCII characters
in class names, though, because people are afraid of using them, partly for a reason.
In practice, it is safest to use only ASCII letters, digits, and hyphen-minus characters
in class names in HTML and CSS. However, a much wider range of characters is per-