PROBLEM with IE and SAFARI

Hi there!
I use the Leafs template to build a new website ( www.beras.eu ). Everything works fine on Firefox or Chrome, but I experience big troubles on IE and Safari. IE shows nothing or navigates to Error 404, and Safari shows just the html code as you can see at the attached image

I can't figure out why does it happens.
Can you please help me to solve that?

Joomla is up to date to 2.5.

try this , open template_css.php and delete this:

<?php
header("Content-type: text/css");
?>

I've done that. The problem on Safari is solved, but it still remains on IE. It is not possible to open the site on all IE versions.

Maybe you just need to refresh hit ctrl+f5 several times

Sorry, what do you mean to refresh? the IE? If you mean that, this is not the case. I've tried on several computers and several IE versions. Always I get the same trouble.

When I open your page in Safari, everything looks fine. Please let me know what is your browser version (Safari and IE) and what OS you have?