function bgImg() {
	var n = new Array("01","02","03","04","05","06","07","08","09","10")
	m = Math.floor(Math.random()*(n.length));
	if(!n[m]) s = "url(images/bg01.jpg) no-repeat center center";
	else if(m>6) s = "url(images/bg"+n[m]+".jpg) no-repeat center bottom";
	else s = "url(images/bg"+n[m]+".jpg) no-repeat center center";
	document.body.style.background = s;
}