var siteExtras = document.getElementById('site_extras');

function startSiteExtras(){
	switchSiteExtras();
	window.setInterval('switchSiteExtras()', 10000);
}

function switchSiteExtras(){
	if(extranum >= siteExtraArrCount){
		extranum = 0;
	}
	siteExtras.innerHTML = siteExtraArr[extranum];
	extranum++;
}

function openMenu(menuName){
	closeMenus();
	document.getElementById(menuName).style.visibility = "visible";
};

function closeMenus(){
	document.getElementById('menuEquipment').style.visibility = "hidden";
	document.getElementById('menuContact').style.visibility = "hidden";
	document.getElementById('menuInfo').style.visibility = "hidden";
	document.getElementById('menuPartner').style.visibility = "hidden";
};

var extranum = getRandom(0, siteExtraArrCount);
startSiteExtras();