Lightbox slide properties

Hi

Sorry if this has been asked before but search came up blank.

I have built a course in Storyline and used the lightbox option to display a couple of mini demos - the problem is that the resultant slides are quite small  especially when viewed on laptops and I have been asked if I can make them bigger.

So is there a way to tweak the properties/size of the lightbox so it displays larger?

thank you for your help