Works for me. Make sure you use https because of HSTS.
Try (OS command line)
ping repl.co
Pinging repl.co [35.186.245.55] with 32 bytes of data:
Reply from 35.186.245.55: bytes=32 time=22ms TTL=116
Reply from 35.186.245.55: bytes=32 time=17ms TTL=116