What an invitation has to answer
A good graduation invitation quietly answers a handful of questions before they are asked. Who is being celebrated, what the ceremony is, where the party is, and how to say you are coming. Leave any of those out and you will get the phone call instead.
Written on a page, those answers have a natural order: the graduate's name and honours up top, the ceremony details, the party after that, and the reply button within easy reach on a phone.
Because graduation is a fully supported event type, the invitation designs are built around exactly this information rather than a generic layout you have to reshape.