window.onload=function(){
	
	colSx = document.getElementById('navColumnOneWrapper');
	colCentrale = document.getElementById('colonnaCentrale');
	colDx = document.getElementById('navColumnTwoWrapper');
	
	var heightColDx = colDx.offsetHeight;
	var heightColCentrale = colCentrale.offsetHeight;
	var heightColSx = colSx.offsetHeight;
	
	if ((heightColDx >= heightColCentrale) && (heightColDx >= heightColSx)) { //la colonna destra e' la piu' alta
		colSx.style.height = heightColDx + "px";
		colCentrale.style.height = (heightColDx-68) + "px";
	}
	if ((heightColSx >= heightColCentrale) && (heightColSx >= heightColDx)) { //la colonna sinistra e' la piu' alta
		colDx.style.height = (heightColSx-80) + "px";
		colCentrale.style.height = (heightColSx-68) + "px";
	}
	if ((heightColDx <= heightColCentrale) && (heightColCentrale >= heightColSx)) { //la colonna centrale e' la piu' alta
		colSx.style.height = (heightColCentrale+68) + "px";
		colDx.style.height = (heightColCentrale-12) + "px";
	}
	
	
}