//####################################################################################//
//###############             Copyright 2008 - Hien Quan             #################//
//###############  No copying or reuse of this code without consent  #################//
//####################################################################################//

//### customise menu scrolling here ###
function window_onscroll(){
  var Yactual = 0;
  var Ymax = 0;
  var def_leftside = document.getElementById("def_leftside"); 
  var def_content = document.getElementById("def_content");
  var def_footer = document.getElementById("def_footer");
  var def_header = document.getElementById("def_header");
  var YOffset = def_header.offsetHeight; 
  Ymax = Math.abs(def_leftside.offsetHeight - def_content.offsetHeight - def_footer.offsetHeight)-20;
  if (getScrollY() > YOffset) {
        Yactual = getScrollY() - YOffset;
  }
  else {
        Yactual = getScrollY();
  }    
  if (Yactual > Ymax) {Yactual = Ymax;}
  def_leftside.style.top = Yactual;
}