<?php
// if uninstall.php is not called by WordPress, die
if (!defined('WP_UNINSTALL_PLUGIN')) {
    die;
}
$option_name = 'Cookies';
delete_option($option_name);
// for site options in Multisite
delete_site_option($option_name);
// drop a custom database table
global $wpdb;
$wpdb->query("DROP TABLE IF EXISTS {$wpdb->prefix}cookies_color");
$wpdb->query("DROP TABLE IF EXISTS {$wpdb->prefix}cookies_content");