true,
'overline' => true,
'underline' => true,
);
$string = strtolower($this->parseCDATA($string));
if ($string === 'none') return $string;
$parts = explode(' ', $string);
$final = '';
foreach ($parts as $part) {
if (isset($allowed_values[$part])) {
$final .= $part . ' ';
}
}
$final = rtrim($final);
if ($final === '') return false;
return $final;
}
}