SERVER
index.html
empty <div id=root>
bundle.js
serves shell
+ static files
1. request
2. empty HTML shell + JS bundle
3. browser fetches data (API)
4. render + interactive (both at once)
blank while
JS loads…
crawler sees this
CLIENT · BROWSER
TIMELINE
nothing visible until the very end — content lands late, all at once
req
shell
JS download
JS execute
data fetch
render