Wrap Flarum in a DIV, so it is within a parent layout

Hi,

I'm looking to insert the Flarum app into a wrapper div, which contains the entire Flarum instance.

Is this possible, so that I can integrate into a basic layout that already exists?

I have customised as much as I can, but my client would prefer to keep the look of the existing website header + centrally aligned page wrapper.

Any tips greatly appreciated.
Thanks

Considering Flarum has some elements aligned with absolute positioning, you'd have to use an iframe or create an extension for it.