RewriteEngine on
RewriteRule ^[^/.]*$ /wfpl_main.php [L]
# Close loophole in security restriction/exception below
-RewriteRule ^.*/.*wfpl_main.php$ /wfpl_main.php [L]
+RewriteRule ^.*/.*wfpl_main.php$ /error_404 [L,R]
<FilesMatch "\.(css|jpg|png)$">
ExpiresActive On