Voici le script
<?PHP
$requete_nombre_message = $connection->prepare('SELECT COUNT(*) idg FROM messages WHERE dest=:dest');
if($requete_nombre_message->execute(array(':dest'=> $_SESSION['xxxx']))){
$nbmessrec = $requete_nombre_message->fetchColumn();
switch ($nbmessrec) {
case '0 < 70':
echo '<input class="vert" type="button" value="'.$nbmessrec.'/reçu'.pluriel($nbmessrec).'"/>';
break;
case '70 < 150':
echo '<input class="orange" type="button" value="'.$nbmessrec.'/reçu'.pluriel($nbmessrec).'"/>;
break;
case '150 < 250':
echo '<input class="red" type="button" value="'.$nbmessrec.'/reçu'.pluriel($nbmessrec).'"/>';
break;
}
?>