function overMenu(menu) {
  menu.style.backgroundColor="#003E68";
  dropMenu(menu,'open');
}

function offMenu(menu) {
  menu.style.backgroundColor="";
  dropMenu(menu,'close');
}

function dropMenu(menu,state) {
  var ul = menu.getElementsByTagName("UL");
  if (ul.length) {
    var drop = ul[0];
    drop.style.display = state == "open" ? "block" : "none";
  }
}