function getSize() {
	var x,y,screenAvailableHeight;
	
	if (self.innerHeight){ // all except IE
		x = self.innerWidth;
		y = self.innerHeight;
	}
	else if (document.documentElement && document.documentElement.clientHeight){ // IE6 Strict Mode
		x = document.documentElement.clientWidth;
		y = document.documentElement.clientHeight;
	}
	else if (document.body){ // other browsers
		x = document.body.clientWidth;
		y = document.body.clientHeight;
	}
	page_width = x;
	page_height = y;
}