I am not sure Maverick understood what you were after...
You can make a custom "button" by using any Sprite, and then use either Mouse or Touch events to tell when someone has clicked on the image. Touch is the best option because it will work with both mouse and Touch.
You can set the opacity to zero, or set the sprite's Visible state to Invisible, BUT neither of those setting will stop the "button" from working. The touch events will still work even though the user can't see it. So you must add another condition saying Sprite is visible, or move the sprite off screen, or use some other method to stop the button from being clickable.
If you are using the built in Button object, then you do have to use CSS to change the buttons appearance, but those types of buttons float above everything else on the canvas and are harder to get the results you want. I would definitely recommend using a sprite instead!