function tab(i) {
	document.getElementById("div-i").style.display = (i == "on-i") ? "block" : "none";
	document.getElementById("div-ii").style.display = (i == "on-ii") ? "block" : "none";
	document.getElementById("div-iii").style.display = (i == "on-iii") ? "block" : "none";
	document.getElementById("naia").style.display = (i == "on-naia") ? "block" : "none";
	
	document.getElementById("tabs-division").className = i;
}