<!DOCTYPE html>
<html>
<body style="border:3px solid;">
  <div style="float:left;">Kitty</div>
  <div>
    <div><div style="clear:both"></div></div>
    Kitty
    <div style="clear:both">.</div>
    <div style="float:left;"></div>
  </div>
  <div id="i">x</div>
  <div style="clear:both"></div>
  <script>
    document.body.offsetTop;
    document.getElementById("i").textContent += "x";
    document.body.offsetTop;
    document.getElementById("i").textContent += "x";
  </script>
</body>
</html>