You can control which items are in front or behind using the Bring to Front and Send to Back commands in the Edit menu. Here’s an example.
The image is now in front of the 2 buttons. We’ve selected it. Now let’s send it to the back.
Choose Send To Back from the Edit menu
The image goes behind the buttons. This is useful when you want to conceal a control behind another object and reveal it during panel operation by hiding the item in front.