function randomBg(){	
var randombgs=["images/background/pic1.jpg", "images/background/pic2.jpg", "images/background/pic3.jpg","images/background/pic4.jpg","images/background/pic5.jpg"];
this.document.body.style.background='#e2d7a1 url("'+randombgs[Math.floor(Math.random()*randombgs.length)]+'") no-repeat center center fixed';
}