Fatal error: Uncaught Error: Undefined constant "DB_HOST" in /var/www/html/app/config/database.php:35 Stack trace: #0 /var/www/html/app/config/database.php(35): constant('DB_HOST') #1 /var/www/html/public/index.php(22): require_once('/var/www/html/a...') #2 {main} thrown in /var/www/html/app/config/database.php on line 35