var wallpaper = new Array ();

wallpaper[0] = ['<img alt="" src="img/wallpapers/wallpaper1.jpg" class="bg" />'];
wallpaper[1] = ['<img alt="" src="img/wallpapers/wallpaper3.jpg" class="bg" />'];
wallpaper[2] = ['<img alt="" src="img/wallpapers/wallpaper12.jpg" class="bg" />'];

var Q = wallpaper.length;

function randomwallpaper() {
	var whichwallpaper=Math.round(Math.random()*(Q-1));
	if (document.getElementById('randomwallpaper')) {
		document.getElementById('randomwallpaper').innerHTML = wallpaper[whichwallpaper];
	}
}