vpnControl/templates/register_box.html

<div class="relcontainer">
  <img id="token" src="/img/token.png" class="img-responsive" alt="token" title="token">
</div>
<form class="form-signin" action="/register" method="post">
  <label for="input-token" class="sr-only">token</label>
  <input type="text" id="input-token" name="token" class="form-control" placeholder="token" required autofocus>
  <label for="input-username" class="sr-only">username</label>
  <input type="text" id="input-username" name="username" class="form-control" placeholder="username">
  <label for="input-password" class="sr-only">passwort</label>
  <input type="password" id="input-password" name="password" class="form-control" placeholder="password">
  <button class="btn btn-lg btn-primary btn-block" type="submit">registrieren</button>
</form>