This has got me stumped : I have a child-theme of Twenty Twelve and the CSS edits I make there work fine, but I'm trying to get rid of (or at least reduce) some of the space "up top" - above the main body.
Inspecting the element in Chrome, I see that HTML has margin-top set to 28px and marked !important. Of course I can't override !important - so I thought I'd just remove it from the original Twenty Twelve style.css file ... but it's nowhere to be found! I've looked in every CSS file Twenty Twelve has - but none of them contain anything like this margin-top: 28px declaration, !important or not. In fact, I can't even find "28px" anywhere in it!
It also seems the HTML element is within an IF statement that checks for older versions of IE...
Where on earth (or in the code) is this HTML margin-top: 28px declaration coming from?