Arranging and positioning two divs below each other in CSS

[anniesjk]

I'm new to CSS, so this question might be dead simple. I am laying out a website and am stuck with positioning.On the site, I have a middle section in which there is a header with some scrollable content underneath. Here's the relevant CSS for the header div:\[code\]#header { position: absolute; margin-left: auto; margin-right: auto; width: 100%; height: auto;}\[/code\]Now, I simply want the content div to immediately follow underneath, and can't figure out how to do that. \[code\]position: relative; top: 0; \[/code\]doesn't seem to work (which I initially expected to). Both divs are on the same logical level and wrapped inside the middle section div. I am probably missing something extremely obvious and easy.