function chnav(id) {
	if (tek == id) return;
	if (tek != "") {
		document.getElementById("nav" + tek).style.display = "none";
		document.getElementById("n" + tek).className = "";
	} else {
		document.getElementById("slogan").style.visibility = "hidden";
	}
	<!--#if expr='"$DOCUMENT_URI" = "/index.shtml"' -->document.getElementById("nmain").className = "snavmn";<!--#endif -->
	document.getElementById("nav" + id).style.display = "block";
	document.getElementById("n" + id).className = "act";
	tek = id;
}
var slogan = 1;
function chslogan(step) {
	document.getElementById("slogan" + slogan).style.display = "none";
	slogan += step;
	if (slogan > max_slogan) slogan = 1;
	else if (slogan == 0) slogan = max_slogan;
	document.getElementById("slogan" + slogan).style.display = "block";
}
function login() {
	location.href = 'https://login.vodokanal.spb.ru/cab00';
}