My last question is, why it is said that Pure Land is outside Triple Realm?
Isn't it true that Buddhalands are part of this universe? So, we can say if Amitabha is west from here, that is not part of triple realm?
Universe is a term use in science that are more materialise while Triple Realm and Pureland are terms use in Buddhism that are more virtually determined by the state of mind. There's also the immaterial world.
Triple Realm (desire, form and formless) or Samsara is the Cycle of rebirths due to karma, afflictions and so on. Pureland on the other hand do not suffer from karmic afflictions and beings are not subject to retrogression. In that sense, the mental state, it's out of Triple realm.