Updating Classic Player Template to Modern Player

Hi all,

Was looking for some ideas on the most efficient way to convert an existing Classic Player template (1004*697) in Storyline 3 to a Modern Player template (1280*720) in Storyline 360

Have been having to re-format every slide in the new template (font sizes, alignment etc.)and was wondering if there is a less time consuming way to do this as we have a lot of courses to change over to the new template 

Any thoughts and suggestions would be greatly appreciated 

Thanks 

Sonal