function windowSize() {
  var width = 0, height = 0;
  if(typeof(window.innerWidth) == 'number') {
    //Non-IE
    width = window.innerWidth;
    height = window.innerHeight;
  } else if(document.documentElement && (document.documentElement.clientWidth || document.documentElement.clientHeight)) {
    //IE 6+ in 'standards compliant mode'
    width = document.documentElement.clientWidth;
    height = document.documentElement.clientHeight;
  } else if(document.body && (document.body.clientWidth || document.body.clientHeight)) {
    //IE 4 compatible
    width = parseInt(document.body.clientWidth);
    height = parseInt(document.body.clientHeight);
  }
  return [width, height];
}

function getPageOffset(element) {
	var x = 0, y = 0;
	while (element) {
		y += element.offsetTop;
		x += element.offsetLeft;
		element = element.offsetParent;
	}
	return [x, y];
}