index = Math.floor(Math.random() * 31) + 1;
document.write("<div id='header_2' style='background-image:url(/fileadmin/mdd/images/header_imgs/bandeaux_mdd" + index + ".jpg); background-repeat:no-repeat;'><div id='header_m'><img height='185' width='980' src='/fileadmin/mdd/images/header_imgs/bandeaux_masque.png'/></div>");