Style your WP Login screen the way you want. By default, the login page is bland, shows the WordPress logo and links to wordpress.org. With this snippet, your login screen will show your site logo, link to your homepage AND add custom styles that you can modify any way you’d like.

See the code…
<?php
if (!class_exists('CustomLoginLogo')) {
// Add your site logo to the WP Login screen. Customize the background color and logo size if desired. https://snipsnip.pro/s/763
class CustomLoginLogo {
public function setCustomLogo() {
$custom_logo_id = get_theme_mod('custom_logo');
$logo_url = wp_get_attachment_image_url($custom_logo_id, 'full');
if ($logo_url) {
echo <<<EOD
<style type="text/css">
body.login { background-color: /* #dad4d5; */ }
body.login div#login h1 a {
background-image: url({$logo_url}) !important;
/* background-size: contain !important; */
/* height: auto !important; */
/* width: 100% !important; */
}
</style>
EOD;
}
}
}
$customLoginLogo = new CustomLoginLogo();
add_action('login_head', array($customLoginLogo, 'setCustomLogo'));
}