Chirpstack Gateway OS on RPi 3B+,what are the login name and password

hi,i installed chirpstack-gateway-os-full-raspberrypi3-20210510105535.rootfs.wic on my RPI by TF card just now.but i don`t know the login name and password,who can tell me? thanks.

Have you seen the documentation? Getting started - ChirpStack open-source LoRaWAN<sup>®</sup> Network Server