function change(id){
	el = document.getElementById(id);
	if (el.style.display == "none")
		el.style.display = "block"; 
	else
		el.style.display = "none"; 
}

function changePort(id){  
	document.getElementById('portfolio1').style.display = "none";
	document.getElementById('portfolio2').style.display = "none";
	document.getElementById('portfolio3').style.display = "none";
	document.getElementById('portfolio4').style.display = "none";
	document.getElementById('portfolio5').style.display = "none";
	
	document.getElementById(id).style.display = "block";
}