[Résolu] Descendre un div de 20 pixels

 <div id="connexion" align="center">  
            <form name="login" acti method="post"> 

             <div id="username">     
                <input id="username-field" type="text" placeholder="votre identifiant"»
            name="username" title="Username" »
            value="" tabindex="1" />
                </div>

                <div id="password" >
                <input id="password-field" type="password" placeholder="votre mot de passe" »
            name="password" title="Password" »
            value="" tabindex="2" />
                </div>

                <div id="submit" style="position:relative; top:20px;" >
                <input type="submit" name="submit" »
            value="ok" tabindex="3" />
                </div>

            </form>
         </div>

#connexion{
 margin-top:20px;
}