Your buyer want to operate his website from WordPress admin panel. And he wish to use his own logo on the admin login page instead of WordPress logo. So how to do this thing.
Step 1 :
Use this code to your functions.php
// Admin login logo
function custom_admin_loginlogo() {
echo '<style type="text/css">
h1 a {background-image: url('.get_bloginfo('template_directory').'/images/client-logo.png) !important; }
</style>';
}
add_action('login_head', 'custom_admin_loginlogo');
Step 2 :
And upload the logo in your themes images folder. Check the admin login. Hope it works fine. Thanks !