---

private async void OnAddClicked(object sender, EventArgs e)
{
    string type = typePicker.SelectedItem?.ToString();
    string number = numberEntry.Text;
    string country = countryEntry.Text;
    string description = descriptionEditor.Text;

    string date = datePicker.Date.ToString("dd.MM.yyyy");

    if (string.IsNullOrWhiteSpace(type) ||
        string.IsNullOrWhiteSpace(number) ||
        string.IsNullOrWhiteSpace(country))
    {
        await DisplayAlert("Ошибка", "Заполните все поля", "OK");
        return;
    }

    Label infoLabel = new Label
    {
        Text =
        $"Тип: {type}\n" +
        $"Номер: {number}\n" +
        $"Страна: {country}\n" +
        $"Дата: {date}\n\n" +
        description,

        FontSize = 16,
        TextColor = Colors.Black
    };

    Button deleteButton = new Button
    {
        Text = "Удалить",
        BackgroundColor = Colors.Red,
        TextColor = Colors.White
    };

    VerticalStackLayout layout = new VerticalStackLayout
    {
        Spacing = 10
    };

    layout.Children.Add(infoLabel);
    layout.Children.Add(deleteButton);

    Frame card = new Frame
    {
        BackgroundColor = Colors.White,
        CornerRadius = 20,
        Padding = 15,
        HasShadow = true,
        Content = layout
    };

    deleteButton.Clicked += (s, args) =>
    {
        documentsLayout.Children.Remove(card);
    };

    documentsLayout.Children.Add(card);

    typePicker.SelectedIndex = -1;
    numberEntry.Text = "";
    countryEntry.Text = "";
    descriptionEditor.Text = "";
}