How would I resize content within h5p video embeds?

Hello h5p forum,

Me and my colleagues use h5p to deliver online training within Moodle. We've noticed that the h5p interactions (the white box within the video frame) is never large enough to house the content within it. We find scrolling down to be a common occurence within the interactions and feel that the content should shrink so it fits the interactive container.

Does anybody know if there is  'non-hacky' way of doing this? Have I overlooked an option somewhere?

If not...

Is the PHP hook for custom CSS the only option?

Many thanks!

Jack Wright