// global configuration
  var deltaX = 30
  var deltaY = 16
  var x0 = 5
  var y0 = 5
  var defaultTarget = 'examplemain'

  var browserName = navigator.appName;
  var browserVersion = parseInt(navigator.appVersion);
  var isIE = false;
  var isNN = false;
  var isDOM = false;
  var isDomIE = false;
  var isDomNN = false;
  var layerok = false;

  var isIE = browserName.indexOf("Microsoft Internet Explorer" )==-1?false:true;
  var isNN = browserName.indexOf("Netscape")==-1?false:true;
  var isOpera = browserName.indexOf("Opera")==-1?false:true;
  var isDOM = document.getElementById?true:false;
  var isDomNN = document.layers?true:false;
  var isDomIE = document.all?true:false;

  if ( isNN && browserVersion>=4 ) layerok=true;
  if ( isIE && browserVersion>=4 ) layerok=true;
  if ( isOpera && browserVersion>=5 ) layerok=true;

  function hideLayer(layerName) {
    if (isDOM)
      document.getElementById(layerName).style.visibility="hidden"
    else if (isDomIE)
      document.all[layerName].style.visibility="hidden";
    else if (isDomNN)
      document.layers[layerName].visibility="hidden";
  }

  function showLayer(layerName) {
    if (isDOM)
      document.getElementById(layerName).style.visibility="visible"
    else if (isDomIE)
      document.all[layerName].style.visibility="visible";
    else if (isDomNN)
      document.layers[layerName].visibility="visible";
  }

  function setyLayer(layerName, y) {
    if (isDOM)
      document.getElementById(layerName).style.top=y
    else if (isDomIE)
      document.all[layerName].style.top=y;
    else if (isDomNN)
      document.layers[layerName].top=y;
  }