title: Highlight button without changing Text, BackColor, Enabled?
body: <p><strong>What would be a good way to highlight a button ?</strong></p>
  
  <p>This is either used or is not allowed to be used:</p>
  
  <ul>
  <li>don't change <code>button.Text</code> (must keep old text)</li>
  <li>don't change <code>button.BackColor</code> (buttons are already very colorful)</li>
  <li>don't change <code>button.Enabled</code> (is used but not enough)</li>
  </ul>
  
  <p><img src="https://i.stack.imgur.com/BBx4g.jpg" alt="enter image description here"></p>
  
  <p>The idea is to have something like a RadioButton-group just with normal buttons. The selected button should be easily seen in <em>the corner of the eye</em>.</p>
  
  <p>Ideas that I also had:</p>
  
  <ul>
  <li><strong>Border / Shading</strong>: Never used that and I don't really have a clue how to change the default button shading or the border style of a single button.</li>
  <li><strong>Font</strong> (Underline)</li>
  <li><strong>Image</strong> (didn't try)</li>
  </ul>