Need some help figuring this out, im creating a cusom login

HI,

Need some help figuring this out, im creating a cusom login using #modal , the login works fine etc.. but what i need is to change the default wordpress login css to a my theme css. here’s what i have so far.

$args = array(

'echo' => true,

'redirect' => ( is_ssl() ? 'https://' : 'http://' ) . $_SERVER['HTTP_HOST'] . $_SERVER['REQUEST_URI'],                        'form_id' => 'loginform',

'label_username' => __( 'Username' ),

'label_password' => __( 'Password' ),

'label_remember' => __( 'Remember Me' ),

'label_log_in' => __( 'Log In' ),

'id_username' => 'user_login',

'id_password' => 'user_pass',

'id_remember' => 'rememberme',

'id_submit' => 'wp-submit',

'remember' => true,

'value_username' => NULL,

'value_remember' => false );

//$args = array('redirect' => home_url()); //get_permalink( get_page( $page_id_of_member_area ) ) );

$args = array( 'redirect' => site_url() );



if(isset($_GET['login']) && $_GET['login'] == 'failed')

{

?>

<div id="login-error" style="background-color: #FFEBE8;border:1px solid #C00;padding:5px;">

<p>Login failed: You have entered an incorrect Username or password, please try again.</p>

</div>

<?php

}



wp_login_form( $args );

but i wish to custom css the input field , button and add a place-holder instead. is that possible.

Here’s my html login form that i wished to incorporate it in.

<form action="#" name="loginform" class="push-down-15">

<div class="form-group">

<input type="text" id="username" required="true" class="form-control  form-control--contact" placeholder="Username">

</div>

<div class="form-group">

<input type="text" id="subject" required="true"  class="form-control  form-control--contact" placeholder="Password">

</div>

<button type="submit" class="btn  btn-primary">SIGN IN</button>

</form>

Thanks for the help.