var ua = navigator.userAgent.toLowerCase();
var isOpera = (ua.indexOf('opera')  > -1);
var isIE = (!isOpera && ua.indexOf('msie') > -1);

function getDocumentHeight() {
  return Math.max(document.compatMode != 'CSS1Compat' ? document.body.scrollHeight : document.documentElement.scrollHeight, getViewportHeight());
}

function getViewportHeight() {
  return ((document.compatMode || isIE) && !isOpera) ? (document.compatMode == 'CSS1Compat') ? document.documentElement.clientHeight : document.body.clientHeight : (document.parentWindow || document.defaultView).innerHeight;
}

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


function showBimage() {
	if (navigator.appName == "Microsoft Internet Explorer") {
//		document.all.semiopacity.style.height=getDocumentHeight();
//		document.all.B_div.style.height=getDocumentHeight();
		document.all.Bimage.style.left=getDocumentWidth()/2-document.all.Bimage.width/2;
		document.all.Bimage.style.visibility="visible";
//		document.all.semiopacity.style.visibility="visible";
//		document.all.B_div.style.visibility="visible";
	}
	else {
		document.all.semiopacity.style.height=document.height;
		document.all.B_div.style.height=document.height;
		document.all.Bimage.style.left=document.width/2-document.all.Bimage.width/2;
		document.all.Bimage.style.visibility="visible";
		document.all.semiopacity.style.visibility="visible";
		document.all.B_div.style.visibility="visible";
	}
}

function hideBimage() {
	document.all.Bimage.style.visibility="hidden";
	document.all.semiopacity.style.visibility="hidden";
	document.all.B_div.style.visibility="hidden";
}