---
phase: 01-grundger-st-tippmechanik
plan: 02
subsystem: ui
tags: [screen-management, onboarding, indexeddb, companion-selection, css-transitions]

requires:
  - phase: 01-01
    provides: "IndexedDB storage layer (openDB, getProgress, saveProgress), types, CSS design system"
provides:
  - "Screen management (showScreen, initApp)"
  - "Welcome screen with companion selection and layout toggle"
  - "Companion definitions (fee/einhorn/fuchs/eule)"
  - "Onboarding flow with IndexedDB persistence"
affects: [01-03, 01-04, 01-05]

tech-stack:
  added: []
  patterns:
    - "Screen routing via CSS class toggle (.screen--active)"
    - "DOM-based UI generation from data arrays (companion cards)"
    - "Event delegation for toggle groups (layout buttons)"

key-files:
  created:
    - src/app.ts
    - src/companion/characters.ts
    - src/ui/screens.ts
  modified:
    - src/main.ts
    - index.html
    - src/styles/main.css

key-decisions:
  - "Screen transitions use CSS opacity + display toggle, no router library"
  - "Companion cards rendered dynamically from characters.ts array, not hardcoded in HTML"

patterns-established:
  - "showScreen(name) pattern: remove .screen--active from all, add to target by id"
  - "initApp checks IndexedDB progress to route returning users directly to forest"

requirements-completed: [FNDN-05, ONBD-01, ONBD-02, ONBD-03, ONBD-04]

duration: 2min
completed: 2026-03-29
---

# Phase 01 Plan 02: Screen Management + Onboarding Summary

**CSS screen management with companion selection (4 characters), DE/CH layout toggle, and IndexedDB-persisted onboarding flow**

## Performance

- **Duration:** 2 min
- **Started:** 2026-03-29T09:05:08Z
- **Completed:** 2026-03-29T09:07:06Z
- **Tasks:** 2
- **Files modified:** 6

## Accomplishments
- Screen management system with CSS fade transitions between 5 app screens
- Welcome screen with 4 companion cards (Lila/Stella/Finn/Elsa) showing emoji and name
- DE/CH keyboard layout toggle with active state styling
- Full onboarding persistence: companion + layout saved to IndexedDB, returning users skip to forest

## Task Commits

Each task was committed atomically:

1. **Task 1: Screen management + companion definitions** - `4b5502f` (feat)
2. **Task 2: Welcome screen UI + onboarding flow** - `20a7670` (feat)

## Files Created/Modified
- `src/app.ts` - Screen management (showScreen, getDB, initApp), routes to welcome or forest
- `src/companion/characters.ts` - 4 companion definitions with type, name, emoji, personality
- `src/ui/screens.ts` - Welcome screen logic: card rendering, layout toggle, start button, save + navigate
- `src/main.ts` - Updated to import and call initApp on DOMContentLoaded
- `index.html` - Welcome screen HTML structure with companion-grid, layout-toggle, start-btn
- `src/styles/main.css` - Welcome screen styles: companion cards, layout buttons, start button with states

## Decisions Made
- Screen transitions use CSS opacity + display toggle (no router library needed for 5 screens)
- Companion cards rendered dynamically from characters.ts data array rather than hardcoded in HTML
- Layout defaults to 'de' (German), toggleable to 'ch' (Swiss)

## Deviations from Plan

None - plan executed exactly as written.

## Issues Encountered
None.

## User Setup Required
None - no external service configuration required.

## Next Phase Readiness
- Screen management ready for lesson, reward, and parent screens
- Forest screen is empty placeholder, ready for 01-03 to populate
- Companion data available for dialogue generation in later plans

---
*Phase: 01-grundger-st-tippmechanik*
*Completed: 2026-03-29*