var currentwin;
function switchwindow(winid){
  el=document.getElementById(winid);
  bs=document.getElementById('blackscreen');
  if (el.style.display=='block'){
     el.style.display='none';
     bs.style.display='none';
  } else {
     currentwin=winid;
     el.style.display='block';
     bs.style.display='block';
  }
}

function closewindow(){
	switchwindow(currentwin);
}

function getClientWidth() {
	return document.compatMode=='CSS1Compat' && !window.opera?document.documentElement.clientWidth:document.body.clientWidth;
}

function getClientHeight() {
	return document.compatMode=='CSS1Compat' && !window.opera?document.documentElement.clientHeight:document.body.clientHeight;
}