not realy a solution but a little hack
you can probably use the page name as an css name
Like this
<backticks>
$CategoryTitle=single_cat_title(”, false);
or
$PostTitle=wp_title(”,false);
</backticks>
and use it in the header.php of your theme
your css file will be
<backticks>
$CategoryTitle.css or $PostTitle.css
</backticks>
this will work .