/*
Global "swap" holder
Use value, null, if no layer initially visible
*/
var currlayerId = "About0";
var picId = "main";

function toglayer(id)
{
if(currlayerId)
setdisplay(currlayerId, "none");

if(picId)
setdisplay(picId, "none");

if(id)
setdisplay(id, "block");

if(picId)
setdisplay(picId, "block");

currlayerId = id;
}

function setdisplay(id, value)
{
var elm = document.getElementById(id);
var elm2 = document.getElementById(picId);
elm.style.display = value;
elm2.style.display = value;
}