Altera a logo / logotipo na tela de login

custom_login_logo.php

/* ----------------

  Altera a logo na tela de login
  Alan

 ----------------- */

add_action( 'login_head', 'custom_login_logo' );
function custom_login_logo() {
  $logo = 'logo-login.png';
  if(!is_null($logo)) {
    echo '<style type="text/css">
      h1 a {
        width: 342px !important;
        height: 48px !important;
        background-size: 342px 48px !important;
        background-image:url('.get_template_directory_uri().'/images/'.$logo.') !important; }
      </style>';
    }
}