I have an add-on with rather a lot of UI options and am trying to find a way to clean it up so that not all the options need to be shown at once. I've noticed that some of the default tools have foldout sections, but I can't figure out what UI component I need to use to get the same behaviour.

Here is an example of what I'm talking about, showing the Color Picker panel open, but Color Palette and Options panels folded up. Is there a simple UI component I can use to emulate the behaviour and visual style of this in my add-on?

[![Brush Color Picker Panel](https://i.stack.imgur.com/nVIAS.png)](https://i.stack.imgur.com/nVIAS.png)