var backgroundSrcs = new Array("back_photo_one.jpg","back_photo_two.jpg","back_photo_three.jpg","back_photo_four.jpg","back_photo_five.jpg", "back_photo_6.jpg")
function pickimage() 
{ 
var bgimage=backgroundSrcs[(Math.floor(Math.random()*(backgroundSrcs.length-1)))] 
document.getElementById("container-bg").style.backgroundImage = "url(/housing/assets/images/template/bg/main/" + bgimage + ")"; 
}