Different layouts between DSCS9 and Windows client

Hi Guys,
we have only recently started working with XiBo and have 5 - DSCS9 and 1-Windows clients.

Now I have created a data record ticker and designed it using HTML and CSS.

The layout looks exactly the same in the preview and on the Windows client, only on the DSCS9 clients there are gaps at the edges of the layout.
Does anyone here know why this is so and what can be done about it?

DSCS9:

Hi geraldmaier and welcome to the community!
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