Formulaire enregistrement mot de passe

<form method="post" action="traitement-creation_pass">
			
				<legend>Se connecter</legend>	
			
			<p><label for="mail">Votre adresse mail</label>:<br/><input type="email" name="mail"id="mail" autofocus  required/>
			<p><label for="pass1">Choississez votre mot de passe</label>:<input type="password" name="pass1" id="pass1" required/>
			<p><label for="pass2">Confirmez votre mot de passe</label>:<input type="password" name="pass2" id="pass2" required/>
			<p><input type="submit" value="valider" class="envoi"/> </p><br/>

<?php error_reporting(E_ALL); ini_set('display_errors', TRUE);ini_set('display_startup_errors', TRUE);?>
		<?php try{
$bdd =new PDO('mysql:host=localhost;
 dbname=reveil; charset=utf8', 'root', '');
// Activation des erreurs PDO
 $bdd->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
// mode de fetch par défaut : FETCH_ASSOC / FETCH_OBJ / FETCH_BOTH
 $bdd->setAttribute(PDO::ATTR_DEFAULT_FETCH_MODE, PDO::FETCH_ASSOC);
} catch(PDOException $e) {
    die('Erreur : ' . $e->getMessage());}?>
	
	<?php
	// Hachage du mot de passe
	$mail= !empty($_POST['mail']) ? $_POST['mail'] : NULL;

			$pass_hache = sha1($_POST['pass1']);
			// Vérification des identifiants
			$sql ='SELECT id, Nom FROM info_membres WHERE Mail = :Mail';
			$datas=array(
			':Mail' => $mail);
			$resultat = $sql->fetch();
			if (!$resultat){echo '<p>Mauvais mail!</p>
			<form method="post" action="verification">
			
				<legend>Se connecter</legend>	
			
			<p><label for="mail">Votre adresse mail</label>:<input type="email" name="mail"id="mail" required/>
			<p><label for="pass">Votre mot de passe</label>:<input type="password" name="pass" id="pass" required/>
			<p><input type="submit" value="valider" class="envoi"/> </p><br/>
			<P><a href="inscription">Inscription</a></p>
			
			</form>';}
			else{session_start();
			$_SESSION['id'] = $resultat['id'];
			$_SESSION['nom'] = $resultat['Nom'];
			
			$sql= 'INSERT INTO info_membres (mot_de_passe) Values(:mot_de_passe) WHERE id='$_SESSION[id]'' ;
			$datas=array(
			':mot_de_passe'=>$pass_hache;
			
			echo '<p>Vous êtes connecté</p>'
			?>
			
			<?php try{
  $req = $bdd->prepare($sql);
  $req->execute($datas);
  
  }catch(Exception $e){
    echo "<br>ERREUR dans la requête ! " . $sql ."<br>" .$e->getMessage();} ?>