How to Change the WordPress Login Logo

functions.php

/** Change the WordPress Login Logo */
add_action('login_head', 'eo_login_logo');
function eo_login_logo()
{
  echo
    '<style type="text/css">
       login h1 a
       {
         background-image: url(' . get_bloginfo('template_directory') . '/images/login-logo.png) !important;
       }
     </style>';
}