How can I change ChoiceLayer's style?

[Zyrean5]

Currently, I'm using the default visual novel style. I want to add a panel behind the choices. I tried creating a custom style and adding it with the godot's own node system, but If I make buttons children of the panel, the code gives me an error and doesn't let me start the dialogic. This happens probably because the button's node placement is hard coded but I couldn't find it where it is. I tried adding a panel in the code, but when I add anything in the code, it stays on the screen even if there are no choice buttons on the screen. The documentation about style has not helped me. Can anybody lend me a hand?