Is there any way to make a background color stretch out to full width of browser?

I am trying to achieve a full width background color behind a code block on my website.

The code block has two divs - one for the background color, and one for the content. The CSS I am using at the moment is as follows:

#Bio {
  background-color: #e5e5e5;
  margin-left: -600px;
  margin-right: -600px;
}

#BioWrapper {
  margin: 0 auto;
  padding: 40px 600px;
}

So basically I am playing around with margins and padding to get the effect, but it then creates extra space to the right, causing unwanted scrolling.

This is the page I am working on: http://blussh.com.au/about/ The grey area with the heading 'heids' is where I am trying to achieve this full width background color.

I am hoping there is an easy fix to my CSS - can anyone help? Thank you!