title: making panel control transparent
body: <p>I have a panel control, that has a background picture on it. I want it to change opacity one I move mouse over it. How can I do that? I tried:</p>
  
  <pre><code>  btnExit.BackColor = Color.FromArgb(20,63,63,63);
    btnExit.BackColor = Color.FromArgb(20);
  </code></pre>
  
  <p>but nothing changes.. Any ideas why this is not working? this panel is sitting on another panel, which also has background picture. Thanks!</p>