private void pictureBoxNormal_Click(object sender, EventArgs e)
        {
            this.Hide();
            FormMinesweeper levelTwo = new FormMinesweeper(40, 16, 16);

            levelTwo.Text         = "Level Two";
            levelTwo.Closed      += (sender1, ex1) => this.Close();
            levelTwo.TextChanged += (sender2, ex2) =>
            {
                FormMinesweeper.ActiveForm.Hide();
                this.Show();
            };
            levelTwo.Show();
        }
        private void pictureBoxHard_Click(object sender, EventArgs e)
        {
            this.Hide();
            FormMinesweeper levelThree = new FormMinesweeper(100, 30, 16);

            levelThree.Text         = "Level Three";
            levelThree.Closed      += (sender1, ex1) => this.Close();
            levelThree.TextChanged += (sender2, ex2) =>
            {
                FormMinesweeper.ActiveForm.Hide();
                this.Show();
            };
            levelThree.Show();
        }
        private void pictureBoxEasy_Click(object sender, EventArgs e)
        {
            this.Hide();
            pictureBoxEasy.Image = Properties.Resources.lvlOne;
            FormMinesweeper levelOne = new FormMinesweeper(10, 9, 9);

            levelOne.Text         = "Level One";
            levelOne.Closed      += (sender1, ex1) => this.Close();
            levelOne.TextChanged += (sender2, ex2) =>
            {
                FormMinesweeper.ActiveForm.Hide();
                this.Show();
            };
            levelOne.Show();
        }