I would like to change the css of a button

Hi all, I would like to use the css from a ligth-button, and add mine (margin, background color etc).
Here is the HTML :

<ion-view view-title="Connexion"> <ion-content> <img class="logo" src="../img/logo_ineat.png" alt="" /> <!-- Formulaire de login --> <form class="list" ng-submit="login.login()"> <!-- <div class="list"> --> <!-- Nom d'utilisateur --> <input class="username-input" style="color:white;" type="text" ng-model="login.username" placeholder="Nom d'utilisateur..."> <!-- Mot de passe --> <input class="password-input"style="color:white;" type="password" ng-model="login.password" placeholder="Mot de passe..."> <!-- Bouton de validation --> <button class="loginButton button" type="submit" name="button">Valider</button> <!-- </div> --> </ion-content> </ion-view>

Here is the css :


position: absolute;
left: 50%;
margin-left: -150px;
background-color: #1E99D5;



But it does nothing. Can you help me ? Thanks !