NafSubnav = {
  timer:null,

  show: function(elem_num) {
    if(NafSubnav.timer) { clearTimeout(NafSubnav.timer); NafSubnav.time=null; }
    for(var i=1;i<=7;i++) {
      var elm = document.getElementById('subnav-item-'+i);
      if(elm) elm.style.display = (i==elem_num) ? '' : 'none';
    }
  },
  
  hide: function(elem_num) {
    NafSubnav.timer = setTimeout(function() { NafSubnav.hideComplete(elem_num); },500);
  },
  
  hideComplete: function(elem_num) {
    if(NafSubnav.timer) { clearTimeout(NafSubnav.timer); NafSubnav.time=null; }
    for(var i=1;i<=7;i++) {
      var elm = document.getElementById('subnav-item-'+i);
      if(elm) elm.style.display =  'none';
    }
  }
};