WordPress default styles not using HTTPS over Proxy Service

Code needed:

// BEGIN NEW TWO LINES
} elseif ( isset( $_SERVER['HTTP_X_FORWARDED_PROTO'] ) && ( 'https' == $_SERVER['HTTP_X_FORWARDED_PROTO'] ) ) {
    return true;
// END NEW TWO LINES

you can add these two lines inside of “is_ssl()” function in “wp-includes/load.php” file.

Finally you will get this:

/**
 * Determines if SSL is used.
 *
 * @since 2.6.0
 * @since 4.6.0 Moved from functions.php to load.php.
 *
 * @return bool True if SSL, otherwise false.
 */
function is_ssl() {
    if ( isset( $_SERVER['HTTPS'] ) ) {
        if ( 'on' === strtolower( $_SERVER['HTTPS'] ) ) {
            return true;
        }

        if ( '1' == $_SERVER['HTTPS'] ) {
            return true;
        }
    } elseif ( isset( $_SERVER['SERVER_PORT'] ) && ( '443' == $_SERVER['SERVER_PORT'] ) ) {
        return true;
    // BEGIN NEW TWO LINES
    } elseif ( isset( $_SERVER['HTTP_X_FORWARDED_PROTO'] ) && ( 'https' == $_SERVER['HTTP_X_FORWARDED_PROTO'] ) ) { // <== NEW
        return true;
        // END NEW TWO LINES
    }
    return false;
}

Adding the following lines of code at the end of my wp-config.php file resolved the redirect conflict.

if (strpos($_SERVER['HTTP_X_FORWARDED_PROTO'], 'https') !== false)
   $_SERVER['HTTPS']='on';