if (document.layers) {
  visible = 'show';
  hidden = 'hide';
} else if (document.all) {
  visible = 'visible';
  hidden = 'hidden';
}

function reveal(menu) {
  if (document.layers) {
    daMenu = document.layers[menu];
  }
  else {
    daMenu = document.getElementById(menu).style;
  }

    daMenu.visibility = "visible";
}

function hide(menu) {
  if (document.layers) {
    daMenu = document.layers[menu];
  }
  else {
    daMenu = document.getElementById(menu).style;
  }
  
  daMenu.visibility = "hidden";
}

function imgOn(imgName) {
        if (document.images) {
            document[imgName].src = eval(imgName + "on.src");
	}
}
function imgOff(imgName) {
        if (document.images) {
            document[imgName].src = eval(imgName + "off.src");
	}
}

// email
function toggleVisibility(id, NNtype, IEtype, WC3type)
{
    if (document.getElementById) {
        eval("document.getElementById(id).style.visibility = \"" + WC3type + "\"");
    } else {
        if (document.layers) {
            document.layers[id].visibility = NNtype;
        } else {
            if (document.all) {
                eval("document.all." + id + ".style.visibility = \"" + IEtype + "\"");
            }
        }
    }
}

function toggleiFrame(id, NNtype, IEtype, WC3type)
{
    if (document.getElementById) {
        eval("document.getElementById(id).style.zIndex = \"" + WC3type + "\"");
    } else {
        if (document.layers) {
            document.layers[id].visibility = NNtype;
        } else {
            if (document.all) {
                eval("document.all." + id + ".style.zIndex = \"" + IEtype + "\"");
            }
        }
    }
}