menuid=1;

function menumouseover(id) {
	for (var i=1;i<6;i++) {
		if (i==menuid || i==id)
			document.getElementById("menu"+i).className="menu"+i+"_2";
		else
			document.getElementById("menu"+i).className="menu"+i+"_1";
	}
}

function menumouseout(id) {
	for (var i=1;i<6;i++) {
		if (i==menuid)
			document.getElementById("menu"+i).className="menu"+i+"_2";
		else
			document.getElementById("menu"+i).className="menu"+i+"_1";
	}
}

function menuclick(id) {
	var menuurls=new Array();
	menuurls[1]="main.htm";
	menuurls[2]="special.htm";
	menuurls[3]="selection.htm";
	menuurls[4]="learning.htm";
	menuurls[5]="interactive.htm";
	menuid=id;
	menumouseout(id);
	document.getElementById("main").src=menuurls[id];
}