I'm trying to extend the height of div within a div that doesn't have a fixed height. I have to do this without using position:absolute because the extended div needs to interact with other divs.
The extended div can't have a fixed height and neither the div it's in...
Is there a way to do this in CSS without using JS?
Update:
To clarify, in the example, I'm trying to extend the height of .extend div from top to bottom of the .main div. .extend should not have a fixed height and should not be position absolute because it needs to push elements that's around it. To make things even more complicated, the divs are for a fluid site so everything except the .extend div must have a width of 100%.
If you specify a height for .extend you will see what I'm trying to achieve but need to do it without a height specified.