This page is not Valid XHTML 1.0 Strict!

Here is the full error provided by W3C

It's compaining about the greater than carrot before the @import

document type does not allow element "style" here.

…e('<style type="text/css" media="all">@import "/modules/simple_karma/simple_k

The element named above was found in a context where it is not allowed. This could mean that you have incorrectly nested elements -- such as a "style" element in the "body" section instead of inside "head" -- or two elements that overlap (which is not allowed).

One common cause for this error is the use of XHTML syntax in HTML documents. Due to HTML's rules of implicitly closed elements, this error can create cascading effects. For instance, using XHTML's "self-closing" tags for "meta" and "link" in the "head" section of a HTML document may cause the parser to infer the end of the "head" section and the beginning of the "body" section (where "link" and "meta" are not allowed; hence the reported error).

Here is the code causing the problem:

<script type="text/javascript">
document.write('<style type="text/css" media="all">@import "/modules/simple_karma/simple_karma_js.css";</style>');

      var karma_only_one_vote = 1;
      var karma_login_page = "user/login";
      var karma_base_path = "/";
    </script>