var timeout	= 500;
var closetimer	= 0;
var ddmenuitem	= 0;

function mopen(id){	mcancelclosetime(); if(ddmenuitem) ddmenuitem.style.visibility = 'hidden'; ddmenuitem = document.getElementById(id); ddmenuitem.style.visibility = 'visible'; }
function mclose(){ if(ddmenuitem) ddmenuitem.style.visibility = 'hidden'; }
function mclosetime(){ closetimer = window.setTimeout(mclose, timeout); }
function mcancelclosetime(){ if(closetimer){ window.clearTimeout(closetimer); closetimer = null; } }
document.onclick = mclose;