why Add a CSS style inside a PHP code comment

why add a css code inside php comment like this :

/**
 * Contains various information about errors thrown by libxml. The error codes
 * are described within the official
 * xmlError API documentation.
 * @link https://php.net/manual/en/class.libxmlerror.php
 */
class LibXMLError
{
    /**
     * <p style="margin-top:0;">   //  <-----------  here
     * the severity of the error (one of the following constants:
     * <b><code>LIBXML_ERR_WARNING</code></b>,   //  <-----------  here
     * <b><code>LIBXML_ERR_ERROR</code></b> or   //  <-----------  here
     * <b><code>LIBXML_ERR_FATAL</code></b>)     //  <-----------  here
     * </p>
     * @var int
     */
    public int $level;