test.com/libs/css/main.css

test.com/libs.php

test.com/libs/test/test/test

<IfModule mod_rewrite.c>
RewriteEngine On
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{DOCUMENT_ROOT}/index.php -f

RewriteRule ^(.*)$  /index.php?path=$1 [QSA]
</IfModule>