We’re coming to Switzerland this summer but starting our trip in Paris, so we need to book a train from Paris to Bern, where we’re staying. Looks like we probably book to Basel and then to Bern (we have the Swiss Travel Pass that will cover us from Basel to Bern), but question - do we book the train from Paris on the SBB site, or is there a better site for that trip? I’m assuming the Swiss Travel Pass doesn’t help us with that particular trip.