var bg_files = new Array("images/bg_lavendel.jpg", "images/bg_echinacea.jpg", "images/bg_camomile_green.jpg", "images/bg_jasmine.jpg");
function getRandomBG() {
	return bg_files[Math.floor(Math.random() * (bg_files.length))];
}

jQuery(document).ready(function() {
	jQuery("#bg").attr("src", getRandomBG());
});