Change wordpress wp-admin login title

[admin]

How can I change my wordpress title of my wp-admin?

I just want to edit the -- Wordpress from the title and change the symbol < that is used.

The following image explains what I'm talking about.

<a href="

https://imgur.com/JBZd1

" rel="nofollow noreferrer"><img src="

https://imgur.com/JBZd1

" alt="the image that explains"></a>

I tried this code:

function my_admin_title($admin_title, $title)
{
    return get_bloginfo('name').' • '.$title;
}

But he only removes from the admin panel, not admin login.

Can someone help me?