RewriteEngine on

RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d

RewriteRule ^(.+)$ index.php?$1 [QSA,L]

ErrorDocument 404 /error.php
ErrorDocument 400 /error.php
ErrorDocument 401 /error.php
ErrorDocument 403 /error.php
ErrorDocument 405 /error.php
ErrorDocument 406 /error.php
ErrorDocument 409 /error.php
ErrorDocument 413 /error.php
ErrorDocument 414 /error.php
ErrorDocument 500 /error.php
ErrorDocument 501 /error.php