window.onload = function(){ 
pickimage ();
}

var backgroundSrcs = new Array("images/banner_adventure1.jpg","images/banner_adventure2.jpg","images/banner_adventure3.jpg",					"images/banner_adventure4.jpg","images/banner_adventure5.jpg","images/banner_adventure6.jpg")

	function pickimage() {
		var bgimage=backgroundSrcs[(Math.round(Math.random()*(backgroundSrcs.length-1)))]

		document.getElementById("body").style.backgroundImage = "url('" + bgimage + "')";
	}