Scroll content within its own div using window's main scrollbar

[CandyMan]

I'm trying to replicate the 'scroll a specific div using the explorer's main scrollbar and hide the content underneath the fixed(position:fixed) header'.Have a look for an example at this website. In the website as you can see, the content in the middle can be scrolled by the window's main scrollbar and the content kind of hides 'underneath' the fixed header. the following is the CSS that I have for the body (the content in the middle):\[code\]#body { position: relative; padding: 0; margin-left: 320px; margin-top: 130px; width: 500px; }\[/code\]and this is the CSS for the fixed header: \[code\]#header { position: fixed; top: 0; text-shadow:0 -1px 0 rgba(0,0,0,0.5); width: 100%; height: 130px; z-index:2;}\[/code\]the content in the middle currently scrolls underneath the fixed header but it show there since my header is just an PNG image. So the text can be seen as it flows underneath the header image when I'm crolling!