private void selectAuthRole(object sender, EventArgs e)
        {
            loginForm login = new loginForm();

            if (sender == runner)
            {
                login.role = "R";
            }
            else if (sender == coordinator)
            {
                login.role = "C";
            }
            else
            {
                login.role = "A";
            }

            this.Close();
            login.Show();
        }