var ua = navigator.userAgent.toLowerCase();
var isIE = ((ua.indexOf("msie") != -1) && (ua.indexOf("opera") == -1) && (ua.indexOf("webtv") == -1)); 
var isGecko = (ua.indexOf("gecko") != -1);
var isSafari = (ua.indexOf("safari") != -1);
var isKonqueror = (ua.indexOf("konqueror") != -1);

function getX(elm) {
  if (elm.offsetParent) return elm.offsetLeft + getX(elm.offsetParent)
  else if (elm.offsetLeft) return elm.offsetLeft;
  else return 0;
}
function getY(elm) {
  if (elm.offsetParent) return elm.offsetTop + getY(elm.offsetParent)
  else if (elm.offsetTop) return elm.offsetTop;
  else return 0;
}
function getById(id) { return document.getElementById(id); }
function rollIt(l, d) {
  var s = (l.className == 'rolled');
  l.className = (s)? 'unrolled': 'rolled';
  getById(d).className = (s)? '': 'none';
  return false;
}