.htaccess for front page static wordpress

Dear all,

I have a few static pages which calls wordpress’ footer and header and wordpress is in the ‘articles’ directory. The problem is I do not know how to configure my static pages on .htaccess so that it appears as clean url as well. Currently the links for such is domain.com/products.php?=something, but I want it to be domain.com/something.html

but this isn’t working with my .htaccess. It only worked when I take away wordpress’ .htaccess codes, but this is not what I want. I want both wordpress and my static pages to have clean code. Please help.

here are the codes from my .htaccess file

RewriteEngine on
RewriteRule ^product1\.html$ http://www.domain.com/product.php?item=product1
<IfModule mod_rewrite.c>
RewriteBase /
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /articles/index.php [L]
</IfModule>

Thanks for your help