I think it’s because of the way layouts are being used.

They add padding and the datepicker has a set PX width, but layouts have % width.

The easiest way to solve thi sis the restructure your page a bit. Try putting cert and expir date in the same colomn as required document.

ps: you can style the datepicker but its very hard and time consuming and probably not worth the effort.

If you would like to keep the layout you can also save space by changing the form orientation in Data View from horizontal to vertical. Lables will move above the inputs.