3 window
.onload = function() {
4 document
.body
.offsetTop
;
5 document
.getElementById('a').style
.display
= 'inline-block';
9 <p>There should be a blue
<em>square
</em> below.
</p>
11 <div id=
"a" style=
"display:none; width:20px; height:40px; background:blue;"></div>
12 <div style=
"float:left; width:20px; height:40px; background:blue;"></div>