Twenty Eleven transparency

Hi there,

I have implemented some code to make header background transparent. The matter is that, if I implement background: transparent; on branding, I got indeed the background transparent, but as the body is white, I don’t really see any difference.

So I implemented the following code in my child theme:

body #page {
	background: transparent;
}

#main, #primary {
	background-color: #fff;
	height: 100%;
}

But now, it appears just half of the screen white and the other half transparent, cause seems #primary block doesn’t reach the bottom, and can’t set a fixed size, cause I would set the block over the footer or it could be not large enough to show post’s text.

So, what am I missing in such of code? What should I add to make it work?

This is the blog’s address: http://www.boarding-gates.com

Thanks in advance!