当点击create database 后页面会出现这种情况，请问是为啥？
Fatal error: Uncaught mysqli_sql_exception: Access denied for user 'root'@'localhost' in /var/www/html/dvwa/dvwa/includes/DBMS/MySQL.php:13 Stack trace: #0 /var/www/html/dvwa/dvwa/includes/DBMS/MySQL.php(13): mysqli_connect() #1 /var/www/html/dvwa/setup.php(23): include_once('...') #2 {main} thrown in /var/www/html/dvwa/dvwa/includes/DBMS/MySQL.php on line 13