Cannot run front after fresh install

Hello,

I try install by follow this guide https://docs.vuestorefront.io/guide/installation/linux-mac.html

everything is fine. but i cannot enter the website.
The message is

This site can’t be reached

xx.xx.xx.xx refused to connect.

I install on Ubuntu 18.04.3 LTS
with port 3000 is already open and can access.

I also try to install by docker follow this https://docs.vuestorefront.io/guide/cookbook/setup.html#_0-introduction
but cannot. By docker, it seems like the port does not mapped properly. ( not show what is the access port )

Thanks.