public function css($group = '*')
    {
        $this->sort();

        $cssList = $this->getLoadedCssList($group);

        list($cssList) = $this->fireEvent('load.css', [ & $cssList ]);

        $cssList = $this->transformListToLinkHtmlNodes($cssList);

        return implode("\n", $cssList);
    }
public function css($group = '*')
    {
        $this->sort();

        $cssList = $this->getLoadedCssList($group);

        list($cssList) = $this->fireEvent('load.css', [ & $cssList ]);

        $cssList = $this->transformListToLinkHtmlNodes($cssList);

        return implode("\n", $cssList);
    }
Returns CSS tags from given group name.
If group name is asterisk (*), will return from all loaded groups.
@param  string $group Group name.
@return string HTML tags as string.