function buildScreen () {
  if (screen.width > 800) {
    document.write('<table cellspacing="0" cellpadding="0" border="0" width="872"><tr><td width="102" valign="top"><img src="/img/balken_links.gif" width="102" height="100" alt="" border="0"></td><td width="770" valign="top">');
  }
}

function buildScreenBottom () {
  if (screen.width > 800) {
    document.write('</td></tr></table>');
  }
}