Change document root folder

    RewriteEngine on
    RewriteCond %{HTTP_HOST} ^domain-name.com$ [NC,OR]
    RewriteCond %{HTTP_HOST} ^www.domain-name.com$
    RewriteCond %{REQUEST_URI} !folder/
    RewriteRule (.*) /folder/$1 [L]

• domain-name.com - Type your own domain name

• folder - Type the name of the sub-folder which has the test/development website

Redirect from root folder to subfolder

RewriteRule ^$ /site [L]

don't forget about use it:

    Options +FollowSymLinks
    RewriteEngine On