[Issue] Reponsive not working when deploy to Github Page

Hello author. I need a little help here. I'm using your markdown-editor with little tweak by myself( for visual only) with Bootstrap.
But somehow , i'm facing really strange issue when deploy to Github Page
It look like my app isn't reponsive as expected. But is still working on localhost

My app: buinguyenhoangtho.github.io/text-markdown-editor

Main Code
Config
Thanks