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<meta http-equiv="Content-Type" content="text/html; charset=gb2312"> <title>Category D</title> <style type="text/css"> html, body { margin:0; } </style> <div style="position:relative; width:100px; height:100px; background-color:#000000;"> <div style="position:absolute; width:20px; height:20px; line-height:20px; left:50%; top:50%; margin:-10px 0 0 -10px; background-color:#F00; text-align:center; cursor:move;" onmousedown="var wc = this;D.start(wc, null, function (property) { var node = wc.parentNode; var a = D.pos(node), b = D.pos(wc); node.style.left = property.left - b.x a.x 'px'; node.style.top = property.top - b.y a.y 'px'; }, null);"> </div>Pull</div> <div style="width:50px; height:50px; line-height:50px; text-align:center; background-color:#F00; position:absolute; cursor:move;" onmousedown="var wc = this;D.start(wc, null, function (property) { wc.style.left = property.left 'px'; wc.style.top = property.top 'px'; }, null);"> </div>Pull<div style="height:1000px;"> </div>