Body

<div class="container">
        <?php echo validation_errors(); ?>
        <?php
        if(isset($message)){
        ?>
        <div class="alert alert-danger"><?php echo $message; ?></div>
        <?php } ?>
        <?php
        $attributes = array('class' => 'form-signin', 'id' => 'login-form');
        echo form_open('login/index', $attributes);
        ?>
        <h2 class="form-signin-heading">Ingreso de usaurios</h2>
        <label for="inputEmail" class="sr-only">Email</label>
        <input type="text" name="inputEmail" class="form-control" placeholder="Email address" value="<?php echo set_value('inputEmail'); ?>">
        <label for="inputPassword" class="sr-only">Password</label>
        <input type="password" name="inputPassword" class="form-control" placeholder="Password" value="<?php echo set_value('inputPassword'); ?>">
        <button class="btn btn-lg btn-primary btn-block" type="submit">Ingresar</button>
      </form>
    </div>