iFrame dimensions

Hello,
Joomla 4
Template Power
Test-website url:

www.cambra.nl/index.php/wb-autoservice/over-ons

In module position bottom-1 I've inserted an iFrame. Tried a lot of hight and with, 100% and auto.
Also in the layout of the template, but nothing seems to work. I would like tu use it also on mobile phones.
Anyone want to help?
kind regards Hennie

Hello,
where is you modalbox on your site, I couldnt find.
The iframe dimension cant be changed, only maybe the size of the modalbox of the iframe

Hello, thank you for your response.

where is you modalbox on your site

Eh... what is a modalbox?

I think you mean a custom module? I disabled editor and edited an Iframe.
But the dimensions are not full screen. I have tried several possibillities..

gr, Hennie

Hello, you insert the dimension for the iframe or your tool or Youtube insert the sizes automatically.
See screenshot

...
Anyway, it has nothing todo with the template