RewriteEngine On
Options All -Indexes
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-l

RewriteRule (.*)$ index.php?url=$1 [QSA,L]

ErrorDocument 400 /error.php
ErrorDocument 401 /error.php
ErrorDocument 403 /error.php
ErrorDocument 404 /error.php
ErrorDocument 500 /error.php
ErrorDocument 502 /error.php
ErrorDocument 504 /error.php