WordPress Site Turns Blank When I Edit 'wp-config'

I’m trying to edit my wp-config file so my wordpress information is hidden on my site. When I edit it, the entire site goes blank. When I go to the wordpress dashboard I get the following error message:

ERROR:The themes directory is either empty or doesn’t exist. Please check your installation

Here is my wp-config file unedited:

<?php
/**
* The base configurations of the WordPress.
*
* This file has the following configurations: MySQL settings, Table Prefix,
* Secret Keys, WordPress Language, and ABSPATH. You can find more information
* by visiting {@link http://codex.wordpress.org/Editing_wp-config.php Editing
* wp-config.php} Codex page. You can get the MySQL settings from your web host.
*
* This file is used by the wp-config.php creation script during the
* installation. You don't have to use the web site, you can just copy this file
* to "wp-config.php" and fill in the values.
*
* @package WordPress
*/

// ** MySQL settings - You can get this info from your web host ** //
/** The name of the database for WordPress */
define('DB_NAME', 'XXXXX');

/** MySQL database username */
define('DB_USER', 'XXXXX');

/** MySQL database password */
define('DB_PASSWORD', 'XXXXXX');

/** MySQL hostname */
define('DB_HOST', 'XXXXXXX');

/** Database Charset to use in creating database tables. */
define('DB_CHARSET', 'utf8');

/** The Database Collate type. Don't change this if in doubt. */
define('DB_COLLATE', '');

/**#@+
* Authentication Unique Keys and Salts.
*
* Change these to different unique phrases!
* You can generate these using the {@link https://api.wordpress.org/secret-   key/1.1/salt/ WordPress.org secret-key service}
* You can change these at any point in time to invalidate all existing cookies. This    will force all users to have to log in again.
*
* @since 2.6.0
*/
define('AUTH_KEY',         '<code>V)^|<}xOl98X. Mm,|P1(q6tAusj5gjFi1.m} [</code>/,q

o’);
define(‘SECURE_AUTH_KEY’, ‘6])[E7esUf-b-_a_r!K=n0SJ-!pr+ERArx,]+#B8D(+kO’);
define(‘LOGGED_IN_KEY’, ‘P-oUq{8S}xo]zu%a5~FN-ssS)DWR=+$]Y q)h;nn>’);
define(‘NONCE_KEY’, ‘M+zr6C1j.Fly%D)&Il>.E!Tq8Ga+;A#EyE.AjFwrWa:+yA0}|xT%’);
define(‘AUTH_SALT’, ‘V#1bgex#Wa`47.BJefJq6[joO9V,8taI~c4Wq{3TJ2_>(?C+|Bw^^’);
define(‘SECURE_AUTH_SALT’, ‘J6nPC&`O5O|Z{-!k>@-!YcK9UzqX=M6; The;TK’);
define(‘LOGGED_IN_SALT’, ‘rxBL~!l~.@%}.ju_[.Rv+;pj$A_nVf?FS6|EU>sr@#’);
define(‘NONCE_SALT’, ‘4$`-yS=LH#qdzidp{!mc-<9|||mi!hila-&!zLHr<‘);

/**#@-*/

/**
* WordPress Database Table prefix.
*
* You can have multiple installations in one database if you give each a unique
* prefix. Only numbers, letters, and underscores please!
*/
$table_prefix = ‘wp_’;

/**
* WordPress Localized Language, defaults to English.
*
* Change this to localize WordPress. A corresponding MO file for the chosen
* language must be installed to wp-content/languages. For example, install
* de_DE.mo to wp-content/languages and set WPLANG to ‘de_DE’ to enable German
* language support.
*/
define(‘WPLANG’, ”);

/**
* For developers: WordPress debugging mode.
*
* Change this to true to enable the display of notices during development.
* It is strongly recommended that plugin and theme developers use WP_DEBUG
* in their development environments.
*/
define(‘WP_DEBUG’, false);

/* That’s all, stop editing! Happy blogging. */

/** Absolute path to the WordPress directory. */
if ( !defined(‘ABSPATH’) )
define(‘ABSPATH’, dirname(__FILE__) . ‘/’);

/** Sets up WordPress vars and included files. */
require_once(ABSPATH . ‘wp-settings.php’);`

I’m trying to add the following code (just before the last line [something about require_once]):

define('WP_CONTENT_FOLDERNAME', 'media');
define('WP_CONTENT_DIR', ABSPATH . WP_CONTENT_FOLDERNAME );
define('WP_CONTENT_URL', 'http://brightpixelstudios.com/'.WP_CONTENT_FOLDERNAME);
define('WP_PLUGIN_DIR', WP_CONTENT_DIR . '/plugins' );
define('WP_PLUGIN_URL', WP_CONTENT_URL.'/plugins');

Any advice would be greatly appreciated! Thanks!