The empire is larger than the total land area of the planet, so the level of technology varies greatly from place to place

First class: The level of technology exceeds that of the earth, for example: Alinge, the city in the sky

Second class: The level of technology is equal to or slightly lower than that of the earth, for example: the imperial capital Shengtian City

Third class: The level of technology is equivalent to that of early 20th century China, for example: the main city of Cárdenas

Fourth-class: The level of science and technology is equal to or slightly higher than that of the Middle Ages, for example, most of the second- and third-tier cities