Sandbox – RSS

I installed WordPress to mydomain.com/blog and put some html around /blog/index.php. Now all templates look very nice, but when I make the browser open /blog/feed/, the html I put around index.php is also wrapped around the rss xml. The browser does not recognize the xml, and I can’t subscribe to the feed. How can I solve this problem? Many thanks in advance.

http://ww.wp.xz.cn/extend/themes/sandbox/