Ionic PWA - Structure Suggestions?

I want to create a PWA with Ionic. Do you have any suggestions about how to structure a page? Or are there any special style elements for PWAs? If I want a centered div for example, this is my idea how to do that:

            <ion-col col-4></ion-col>
            <ion-col col-4 text-center>
                <div style="border: 1px solid #000000" padding>
                    Lorem ipsum
            <ion-col col-4></ion-col>

Or is there a better way to do something like this? I would be happy about tips!