// Browser Window Size and Position
// copyright Stephen Chapman, 3rd Jan 2005, 8th Dec 2005
// you may copy these functions but please keep the copyright notice as well
function pageWidth() 
{return window.innerWidth != null? window.innerWidth : 
document.documentElement && 
document.documentElement.clientWidth ?       
document.documentElement.clientWidth : 
document.body != null ? 
document.body.clientWidth : null;} 

function pageHeight() 
{return  window.innerHeight != null? window.innerHeight : 
document.documentElement && 
document.documentElement.clientHeight ?  
document.documentElement.clientHeight : 
document.body != null? 
document.body.clientHeight : null;} 

function posLeft() 
{return typeof window.pageXOffset != 'undefined' ? window.pageXOffset :
document.documentElement && 
document.documentElement.scrollLeft ? 
document.documentElement.scrollLeft : 
document.body.scrollLeft ? 
document.body.scrollLeft : 0;} 

function posTop() {return typeof window.pageYOffset != 'undefined' ?  window.pageYOffset : 
document.documentElement && 
document.documentElement.scrollTop ? 
document.documentElement.scrollTop : 
document.body.scrollTop ? 
document.body.scrollTop : 0;} 

function posRight() {return posLeft()+pageWidth();} 

function posBottom() {return posTop()+pageHeight();}