function windowHeight(){
	//IE
	if(!window.innerHeight)
	{
		//strict mode
		if(!(document.documentElement.clientHeight == 0))
		{
			return document.documentElement.clientHeight;
		}
		//quirks mode
		else
		{
			return document.body.clientHeight;
		}
	}
	//w3c
	else
	{
		return window.innerHeight;
	}
}