Draggable UI / Boxes in Forge -> Confluence

Hi everyone. I’m still a massive newbie, but just got a fairly basic app working over the last few weeks.

Is there a component like a box? Or some documentation talking about:

  1. A box type component (e.g. like a div). Whenever I try using anything like
    , it won’t recognise this - I assume it’s not a part of ForgeUI.
  2. A draggable functionality

This is the type of thing I mean: How To Create a Draggable HTML Element

I’m looking on this list of components and cannot quite work out what might be a box-like component.
https://developer.atlassian.com/platform/forge/ui-kit-components/ui1-index/

If no documentation, does anyone know of a bitbucket example where someone has done this?