function modif_class(id_div, valeur_class) {
document.getElementById(id_div).className = valeur_class; 
}
function setCook2(nom,valeur,jours) {
 var expDate = new Date()
 expDate.setTime(expDate.getTime() + (jours * 24 * 3600 * 1000))
 document.cookie = nom + "=" + escape(valeur)
 + ";expires=" + expDate.toGMTString()
}
function delCook(nom) { setCook2(nom,"",-1) }
function getCook(nom) {
    deb = document.cookie.indexOf(nom + "=")
     if (deb >= 0) {
       deb += nom.length + 1
        fin = document.cookie.indexOf(";",deb)
        if (fin < 0) fin = document.cookie.length
       return unescape(document.cookie.substring(deb,fin))
      }
return ""
}
function writediv(texte, nomdiv)
{
document.getElementById(nomdiv).innerHTML = texte;
}
function verif_banniere(){
	if(getCook('guieeb_ban') == '')
	modif_class('image_header', 'image_header_defaut');
	else
	modif_class('image_header', getCook('guieeb_ban'))
}