PHP variable in javascript

$db = new Database($config['server'], $config['user'], $config['pass'], $config['database'], $config['tablePrefix']);
$db->connect();
$sql = "SELECT lt FROM meniu";
$countRows = $db->query($sql);
while ($countRow = $db->fetch_array($countRows)) {
echo "<li class='sub'><a href='javascript:void(0)' onclick='open_url('content.php?id=','my_site_content');'>".$countRow['lt']."</a></li>";
}
$db->close();