function nextabout(next) {
    var idx = document.aboutform.aboutselect.selectedIndex+next;
    if (idx < 0) idx = document.aboutform.aboutselect.options.length-1;
    if (idx > document.aboutform.aboutselect.options.length-1) idx = 0;
    document.location = document.aboutform.aboutselect.options[idx].value;
}

function catthemes (idx) {
    var div = document.getElementById(idx);
	if (div.style.display=="block")
	{
		div.style.display="none";
		document.getElementById("sign"+idx).innerHTML="+";
	}
	else
	{
		div.style.display="block";
		document.getElementById("sign"+idx).innerHTML="-";		
	}
}