private void pictureBox_startDemo_Click(object sender, EventArgs e)
 {
     FormDemoVisual mFormDemo = new FormDemoVisual();
     mFormDemo.Show();
 }
 private void pictureBox_demo_back_Click(object sender, EventArgs e)
 {
     FormDemoVisual mFormDemoVisual = new FormDemoVisual();
     mFormDemoVisual.Show();
     this.Dispose();
 }