var currNav = null

function showsubnav(intId){
	var el=document.getElementById("subnav"+intId)
	if(el!=null){
		if(el!=currNav){hidesubnav()}
		el.style.display="block";currNav=el
	}
}

function hidesubnav(){
	if(currNav!=null){currNav.style.display="none";currNav=null}
}