Chrome says 'ERR_NAME_NOT_RESOLVED' for the 'DEMO' link

[zukaishi]

* Access from Tokyo, Japan
* MacOS Mojave version 10.14.6
* Google Chrome version: 77.0.3865.120 (official build)

Steps to reproduce

Click on the DEMO link on README.md

Expected behavior

Can run a demo

Actual behavior

It was confirmed on the screen the DEMO could not be executed and was not accessible.

Chrome says 'ERR_NAME_NOT_RESOLVED' http://vue-editor.beblog.cn/