var bgImages = new Array('_img/bg1.gif', '_img/bg2.gif','_img/bg3.gif','_img/bg4.gif','_img/bg5.gif');

function randomIndex() {
	var index = Math.floor(Math.random()*bgImages.length);
	return index;
}
function randomBgImage(id) {
	var d = document;
	var e = d.getElementById(id);
	var rand = randomIndex();
	var newImg = "url(" + bgImages[rand] + ")";
	e.style.backgroundImage = newImg;
}


/* open new centered window with scrolling ability */
/* USAGE: javascript:openPop('filename.html','windowname', width, height); */


function openWin(url,name,popW,popH) {
        version = navigator.appVersion;
	var w = 800, h = 600;
        if (version.toLowerCase().indexOf("mac")!=-1) {
                    popW = eval("popW-18");
        }
	if (document.all || document.layers) {
		w = screen.availWidth;
		h = screen.availHeight;
	}
	var leftPos = (w-popW)/2, topPos = (h-popH)/2;
	window.open(url,name,'width=' + popW + ',height=' + popH + ',scrollbars=yes,toolbar=no,status=yes,resizable=no,top=' + topPos + ',left=' + leftPos);void(0);
}




/* open new centered window without scrolling ability */
/* USAGE: javascript:openPop('filename.html','windowname', width, height); */


function openPop(url,name,popW,popH) {
        version = navigator.appVersion;
	var w = 800, h = 600;

	if (document.all || document.layers) {
		w = screen.availWidth;
		h = screen.availHeight;
	}
	var leftPos = (w-popW)/2, topPos = (h-popH)/2;
	window.open(url,name,'width=' + popW + ',height=' + popH + ',scrollbars=no,toolbar=no,status=yes,resizable=no,top=' + topPos + ',left=' + leftPos);void(0);
}


//no spam
// USAGE: javascript:doMail('user','domain.com')
function doMail(user,domain) {
	locationstring = "mailto:" + user + "@" + domain;
	window.location = locationstring;
}


function unblur() {
    this.blur();
}

function blurElements() {
    
    var links = document.getElementsByTagName("a");
    for(i = 0; i < links.length; i++) {
        links[i].onfocus = unblur;
    }
}


/* image preloading */
function preload(imgName, imgSrc) {
    if (loadFlag) {
        eval(imgName + ' = new Image()');
        eval(imgName + '.src = "' + imgSrc + '"');
        return imgName;
    }
}