With 3.xx versions of Pod::Simple and Pod::Simple::HTML you can specify the CSS source using the html_css() method:

  ...
  $parser->output_string($html);
  $parser->html_css(qq(<link rel="stylesheet" href="$stylesheet"/>));
  $parser->parse_file($file);
  ...
[download]

That way you don't have to do the s///.

An alternative approach to the general problem would be to use Pod::Webserver.

--
John.