I don’t know but the li element margin-top will only work if it’s large than margin-bottom of h2 element, i would like to know why?
<h2 style="padding:0px; margin:0; height:30px; line-height:30px; background-color:#FF0000; font-size:18px; font-family:Arial; margin-bottom:10px;">Test1</h2>
<ul style="list-style:none; padding:0; margin:0;">
<li style="height:50px; line-height:50px; background-color:#00FF00; font-size:12px; font-family:Arial; margin-top:10px;">Test2</li>
</ul>
thanks.
What you describe sounds a lot like collapsing margins.
I suggest having a look at http://reference.sitepoint.com/css/collapsingmargins as the issue is covered in detail along with ways to fix it.