Change logo and link on the WordPress login page

functions.php

/**
 * Change the logo on the WordPress login page from the WordPress logo to your own custom logo
 */
function mytheme_change_login_logo() {
	echo '<style type="text/css">#login h1 a {background:url(' . trailingslashit( get_stylesheet_directory_uri() ) . 'images/your-logo.svg)' . ' no-repeat center center;width: 100%;background-size: contain}</style>';
}
add_action( 'login_enqueue_scripts', 'mytheme_change_login_logo' );

/**
 * Change the logo link on the WordPress login page from wordpress.org to your own site URL
 */
function mytheme_change_login_logo_link( $url ) {
	return home_url( '/' );
}
add_filter( 'login_headerurl', 'mytheme_change_login_logo_link' );