function setLongest() {
 wysokosc_okna = document.body.clientHeight; 
 if(navigator.userAgent.search(/msie/i)!= -1) {
		
			if (document.getElementById("head").offsetHeight + document.getElementById("body").offsetHeight + document.getElementById("footbg").offsetHeight < wysokosc_okna) {
	document.getElementById("body").style.height =  (wysokosc_okna - document.getElementById("head").offsetHeight  )-document.getElementById("footbg").offsetHeight+"px";

	//alert(wysokosc_okna );
			}
			
			
} else {
	if (document.getElementById("head").offsetHeight + document.getElementById("body").offsetHeight + document.getElementById("footbg").offsetHeight < window.innerHeight) {
	document.getElementById("body").style.height =  (window.innerHeight - document.getElementById("head").offsetHeight  )-document.getElementById("footbg").offsetHeight+"px";

	//alert("wyknałem  " );
	}
	

}



	
}