You can use node to start the server on port 4000.
node server.js
Edit :
- simple-page.html (contains instructions)
- css/simple-page.css
And improve :
- logo
- headings
- intuitive keyboard navigation
- CSS deactivation
Use VoiceOver or NVDA to make sure the page is entirely read at loading.
Edit :
- js/chat.js (contains instructions)
- chat.html
- css/chat.css
And help the user indicating that some parts of the page have changed.
Use aria attributes : WAI Aria