Hi. Your code is incorrect. It does not take under consideration which page are you viewing currently. You just request the id variable from the URL. This could also be a category id when you are viewing a category page or a user id when you are viewing a user page. The code you provided will work only for item pages. So you will have probably to clarify on what pages you want this to be applied and the update the code accordingly.

ok, thanks for your reply. So I've tried a different approach and am calling the category using

$option = JRequest::getCmd('option');
$view = JRequest::getCmd('view');

if ($option == "com_k2" && $view == "item")
{
	$K2Itemid = JRequest::getInt('id');
	$db = JFactory::getDBO();
	$db->setQuery("SELECT catid FROM #__k2_items WHERE id = ".$K2Itemid);
	$K2Catid = $db->loadResult();
	$pageclass = "category-".$K2Catid;

}
else
{
	$pageclass = "not-k2";
}