This is a Next.js project bootstrapped with create-next-app.

Getting Started

First, run the development server:

npm run dev
# or
yarn dev
# or
pnpm dev
# or
bun dev

Open http://localhost:3000 with your browser to see the result.

You can start editing the page by modifying app/page.tsx. The page auto-updates as you edit the file.

This project uses next/font to automatically optimize and load Geist, a new font family for Vercel.

Learn More

To learn more about Next.js, take a look at the following resources:

• Next.js Documentation - learn about Next.js features and API.
• Learn Next.js - an interactive Next.js tutorial.

You can check out the Next.js GitHub repository - your feedback and contributions are welcome!

Deploy on Vercel

The easiest way to deploy your Next.js app is to use the Vercel Platform from the creators of Next.js.

Check out our Next.js deployment documentation for more details.

Timeline View Persistence

The timeline UI persists user view preferences in localStorage under the htt.* namespace:

• htt.collapsedEras: array of era IDs the user collapsed.
• htt.selectedFilters: array of selected tag filters.
• htt.viewport: object with { zoom: number, position: { x: number, y: number } } storing zoom level and pan offset.

These are loaded on mount and saved whenever they change (viewport updates are debounced ~250ms). Clearing browser storage will reset the view to defaults.

Teacher Login TTL (15-minute inactivity)

• Auth is handled by Supabase; we do not store tokens in our own storage.
• We store only an expiry timestamp at htt.teacher.expiresAt.
• On sign-in, a 15-minute inactivity TTL is set; any user activity (mouse, key, scroll, touch) refreshes the TTL.
• If there’s no activity for 15 minutes, we automatically sign out with Supabase.
• On page load, if the TTL has expired, we sign out immediately.
• UI “teacher mode” reflects actual Supabase auth plus the TTL; the local timestamp is never used to bypass auth.

This keeps preferences in localStorage while avoiding exposing sensitive credentials to the browser beyond Supabase’s standard session storage.