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// Login Logo
add_action( 'login_head', 's9_login_logo' );
function s9_login_logo() {
	echo '<style type="text/css">
		h1 a {
			background-image: url('/wp-content/themes/themename/assets/svg/logo.svg') !important;
			width: 140px !important;
			height: 140px !important;
			background-size: contain !important;
 		}
    </style>';
}

// Login URL
add_filter( 'login_headerurl', 's9_loginlogo_url' );
function s9_loginlogo_url( $url ) {
	return get_home_url();
}