function BrowserDetect() {
   var ua = navigator.userAgent.toLowerCase(); 

   // browser name
   this.isKonqueror   = (ua.indexOf('konqueror') != -1); 
   this.isSafari      = (ua.indexOf('safari') != - 1);
   this.isOmniweb     = (ua.indexOf('omniweb') != - 1);
   this.isOpera       = (ua.indexOf('opera') != -1); 
   this.isIcab        = (ua.indexOf('icab') != -1); 
   this.isAol         = (ua.indexOf('aol') != -1); 
   this.isIE          = (ua.indexOf('msie') != -1 && !this.isOpera && (ua.indexOf('webtv') == -1) ); 
   this.isMozilla     = (this.isGecko && ua.indexOf('gecko/') + 14 == ua.length);
   this.isFirefox     = (ua.indexOf('firefox/') != -1 || ua.indexOf('firebird/') != -1);
   this.isNS          = ( (this.isGecko) ? (ua.indexOf('netscape') != -1) : ( (ua.indexOf('mozilla') != -1) && !this.isOpera && !this.isSafari && (ua.indexOf('spoofer') == -1) && (ua.indexOf('compatible') == -1) && (ua.indexOf('webtv') == -1) && (ua.indexOf('hotjava') == -1) ) );
   
    // browser version
   this.versionMinor = parseFloat(navigator.appVersion); 
   
   // correct version number
   if (this.isMozilla) {this.versionMinor = parseFloat( ua.substring( ua.indexOf('rv:') + 3 ) );}
   else if (this.isIE && this.versionMinor >= 4) {this.versionMinor = parseFloat( ua.substring( ua.indexOf('msie ') + 5 ) );}
   else if (this.isOpera) {this.versionMinor = parseFloat( ua.substring( ua.indexOf('opera') + 6 ) );}

   this.versionMajor = parseInt(this.versionMinor); 
   
   // dom support
   this.isDOM1 = (document.getElementById);
   this.isDOM2Event = (document.addEventListener && document.removeEventListener);
   
   // css compatibility mode
   this.mode = document.compatMode ? document.compatMode : 'BackCompat';

   // platform
   this.isWin    = (ua.indexOf('win') != -1);
   this.isWin32  = (this.isWin && ( ua.indexOf('95') != -1 || ua.indexOf('98') != -1 || ua.indexOf('nt') != -1 || ua.indexOf('win32') != -1 || ua.indexOf('32bit') != -1 || ua.indexOf('xp') != -1) );
   this.isMac    = (ua.indexOf('mac') != -1);
   this.isUnix   = (ua.indexOf('unix') != -1 || ua.indexOf('sunos') != -1 || ua.indexOf('bsd') != -1 || ua.indexOf('x11') != -1)
   this.isLinux  = (ua.indexOf('linux') != -1);
   
   // specific browser shortcuts
   this.isIE5x = (this.isIE && this.versionMajor == 5);
   this.isIE55 = (this.isIE && this.versionMinor == 5.5);
   this.isIE5up = (this.isIE && this.versionMajor >= 5);
   this.isIE6x = (this.isIE && this.versionMajor == 6);
   this.isIE6up = (this.isIE && this.versionMajor >= 6);
}

var browser = new BrowserDetect();
if ((browser.isIE55 || browser.isIE6x) && browser.isWin32) // if IE5.5+ on Win32, then display PNGs with AlphaImageLoader
{
	browser.alphaNotSupported = true;
}

function showAlpha()
{
	if (browser.alphaNotSupported) {
		this.style.filter='progid:DXImageTransform.Microsoft.AlphaImageLoader(src="img/' +this.className+ '_bck.png", sizingMethod="crop")';
	}
	else {
		this.style.background='url("img/' +this.className+ '_bck.png") no-repeat';
	}
}

function getStartedAlpha()
{
	document.getElementById('logo').showAlpha = showAlpha;
	document.getElementById('logo').showAlpha();

	for (x=0; x<document.getElementsByClassName("header").length; x++)
	{
		document.getElementsByClassName("header")[x].showAlpha = showAlpha;
		document.getElementsByClassName("header")[x].showAlpha();
	}
	for (y=0; y<document.getElementsByClassName("inner").length; y++)
	{
		document.getElementsByClassName("inner")[y].showAlpha = showAlpha;
		document.getElementsByClassName("inner")[y].showAlpha();
	}
	for (z=0; z<document.getElementsByClassName("footer").length; z++)
	{
		document.getElementsByClassName("footer")[z].showAlpha = showAlpha;
		document.getElementsByClassName("footer")[z].showAlpha();
	}
	for (j=0; j<document.getElementsByClassName("intro").length; j++)
	{
		document.getElementsByClassName("intro")[j].showAlpha = showAlpha;
		document.getElementsByClassName("intro")[j].showAlpha();
	}
}

function rollIntro(myIntroDiv,mod)
{
	imgAppendix = (mod=="over") ? "_on" : "";
	if (browser.alphaNotSupported) {myIntroDiv.style.filter='progid:DXImageTransform.Microsoft.AlphaImageLoader(src="img/intro_bck' +imgAppendix+ '.png", sizingMethod="crop")';}
	else {myIntroDiv.style.background='url("img/intro_bck' +imgAppendix+ '.png") no-repeat';}
}