<IfModule mod_rewrite.c>
    RewriteEngine on

    RewriteBase /
    RewriteCond %{REQUEST_FILENAME} !-f
    RewriteCond %{REQUEST_FILENAME} !-d
    RewriteCond %{REQUEST_URI} !(.*)/$
    RewriteRule ^(.*) $1/ [R,L]

    RewriteCond %{REQUEST_FILENAME} !-f
    RewriteCond %{REQUEST_FILENAME} !-d
    RewriteCond %{REQUEST_URI} (.*)/$ [NC]
    RewriteRule ^(.*)/$ /?page=$1 [L,QSA]
</IfModule>