I tried to do this, but either it didn't work, or I have the wrong concept of how "templates" within a device work.

Within each device, each page in that device has a different theme, which is pretty unintuitive! see below:

what I want is that ALL pages within the same device have the same theme...for example the same button type, etc, of page1.

how do I create a template so that I can apply it to each successive page within the device?