<!DOCTYPE html>
<html>
  <head>
    <title>Test mpadded</title>
    <style type="text/css">
      div#bigsquare {
        position: absolute;
        width: 100px;
        height: 100px;
        background: blue;
      }

      div#smallsquare {
        position:absolute;
        width: 20px;
        height: 20px;
        left: 20px;
        top: 10px;
        background: red;
      }
      /*left = lspace = 20px;
        top = heightBig - voffset - heightSmall;
            = 50 - 30 - 10
            = 10px */
      </style>
  </head>
  <body>
    <div id="bigsquare">
      <div id="smallsquare">
      </div>
    </div>
  </body>
<html>