You cannot style a variable such as $ip['countryName']
You can only style elements like p,div, etc, or classes and ids.
If you want to style $ip['countryName'] there are several ways.
You can echo it within an element:
echo '<p id="style">'.$ip['countryName'].'</p>';
echo '<span id="style">'.$ip['countryName'].'</span>';
echo '<div id="style">'.$ip['countryName'].'</div>';
If you want to style both the variables the same style, then set a class like:
echo '<p class="style">'.$ip['cityName'].'</p>';
echo '<p class="style">'.$ip['countryName'].'</p>';
You could also embed the variables within your actual html rather than echoing them out within the code.
$city = $ip['cityName'];
$country = $ip['countryName'];
?>
<div class="style"><?php echo $city ?></div>
<div class="style"><?php echo $country?></div>