Layout on low resolution

Hello! First of all, let’s declare what I’m using: WP 3.2.1 and a child theme of TwentyEleven. Here’s the link: virgilio.lorenzoraffio DOT com

When you visit the site with a “normal” PC resolution, you get this:
http://img840.imageshack.us/img840/610/86700170.jpg

So far, so good. all is displayed properly.
Now let’s use a lower resolution, for example on iPhone (or also reducing the size of your browser window)…
http://img231.imageshack.us/img231/5540/img0437a.png

As you can see, the header image is displayed “large”.. but the other content is.. reduced! How can I have something like this (where all is reduced mantaining proportions)?
http://img651.imageshack.us/img651/3107/img0438p.png

I tried for example setting max-width for #page to a % value instead of 1000px, but it’s the same..

Hope you can help me.. thanks in advance guys!!!!!!

— Lorenzo