diff --git a/.python-version b/.python-version
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+3.13
diff --git a/devdocs/v1/IMPLEMENTATION_PLAN.md b/devdocs/v1/IMPLEMENTATION_PLAN.md
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+# GoalsBreakDown - Implementation Plan
+
+## 1. Project Structure
+
+```
+GoalsBreakDown/
+├── app.py                      # Flask application entry point
+├── config.py                   # Configuration constants
+├── database.py                 # TinyDB initialization and operations
+├── auth.py                     # Authentication helpers
+├── requirements.txt            # Python dependencies
+├── data/                       # TinyDB data directory
+│   └── db.json                 # TinyDB database file
+├── static/
+│   ├── css/
+│   │   ├── style.css           # Global styles
+│   │   ├── goals.css           # Goal page styles
+│   │   └── tasks.css           # Task page styles
+│   └── js/
+│       ├── api.js              # API client utilities
+│       ├── auth.js             # Authentication logic
+│       ├── goals.js            # Goal page logic
+│       ├── tasks.js            # Task page logic
+│       └── sortable.min.js     # Drag-and-drop library
+└── templates/
+    ├── base.html               # Base template with navigation
+    ├── login.html              # Login page
+    ├── register.html           # Registration page
+    ├── goals.html              # Goal CRUD page
+    └── tasks.html              # Task CRUD page with scroll view
+```
+
+## 2. Dependencies & Environment Management
+
+### 2.1 Environment Setup (uv)
+```bash
+# Initialize project with uv
+uv init --no-readme
+
+# Add dependencies
+uv add flask tinydb bcrypt
+
+# Run the application
+uv run python app.py
+```
+
+### 2.2 requirements.txt (managed by uv)
+```
+flask==3.0.0
+tinydb==4.8.0
+bcrypt==4.1.2
+```
+
+### 2.3 pyproject.toml (auto-generated by uv)
+```toml
+[project]
+name = "goalsbreakdown"
+version = "0.1.0"
+requires-python = ">=3.10"
+dependencies = [
+    "flask>=3.0.0",
+    "tinydb>=4.8.0",
+    "bcrypt>=4.1.2",
+]
+```
+
+## 3. Database Schema (TinyDB)
+
+### 3.1 Collections (TinyDB Tables)
+
+**users** table:
+```json
+{
+  "user_id": 1,
+  "username": "admin",
+  "password_hash": "$2b$12$...",
+  "role": "admin",
+  "max_goals": 10
+}
+```
+
+**goals** table:
+```json
+{
+  "goal_id": 1,
+  "user_id": 1,
+  "title": "Learn Python",
+  "activated": true
+}
+```
+
+**tasks** table:
+```json
+{
+  "task_id": 1,
+  "goal_id": 1,
+  "title": "Complete basics",
+  "desc": "Learn variables, loops, functions",
+  "status": "doing",
+  "start_time": "2026-05-08T10:00:00",
+  "finished_time": null,
+  "order": 1.0
+}
+```
+
+### 3.2 Database Initialization
+
+```python
+# database.py responsibilities:
+# - Initialize TinyDB with data/db.json
+# - Create tables: users, goals, tasks
+# - Seed admin user on first run (username: admin, password: admin123)
+# - Provide CRUD helper functions for each table
+```
+
+## 4. API Endpoints
+
+### 4.1 Authentication
+
+| Method | Endpoint | Description | Auth Required |
+|--------|----------|-------------|---------------|
+| POST | `/api/auth/register` | Register new user | No |
+| POST | `/api/auth/login` | Login user | No |
+| POST | `/api/auth/logout` | Logout user | Yes |
+| GET | `/api/auth/me` | Get current user info | Yes |
+
+**POST /api/auth/register**
+- Request: `{ "username": str, "password": str }`
+- Response: `{ "success": bool, "message": str, "user_id": int }`
+- Validation: username unique, password min 6 chars
+- Default: role="user", max_goals=5
+
+**POST /api/auth/login**
+- Request: `{ "username": str, "password": str }`
+- Response: `{ "success": bool, "message": str, "user": { user object } }`
+
+**GET /api/auth/me**
+- Response: `{ "user_id": int, "username": str, "role": str, "max_goals": int }`
+
+### 4.2 Goals
+
+| Method | Endpoint | Description | Auth Required |
+|--------|----------|-------------|---------------|
+| GET | `/api/goals` | List all goals for current user | Yes |
+| POST | `/api/goals` | Create new goal | Yes |
+| PUT | `/api/goals/<goal_id>` | Update goal | Yes |
+| DELETE | `/api/goals/<goal_id>` | Delete goal | Yes |
+| PATCH | `/api/goals/<goal_id>/toggle` | Toggle activated status | Yes |
+
+**GET /api/goals**
+- Response: `[ { goal objects } ]`
+- Note: Returns all goals (activated and deactivated)
+
+**POST /api/goals**
+- Request: `{ "title": str }`
+- Response: `{ "success": bool, "goal_id": int, "message": str }`
+- Validation: Check user's max_goals limit before creation
+
+**PUT /api/goals/<goal_id>**
+- Request: `{ "title": str, "activated": bool }`
+- Response: `{ "success": bool, "message": str }`
+- Validation: Goal must belong to current user
+
+**DELETE /api/goals/<goal_id>**
+- Response: `{ "success": bool, "message": str }`
+- Cascade: Delete all tasks associated with this goal
+
+**PATCH /api/goals/<goal_id>/toggle**
+- Response: `{ "success": bool, "activated": bool }`
+
+### 4.3 Tasks
+
+| Method | Endpoint | Description | Auth Required |
+|--------|----------|-------------|---------------|
+| GET | `/api/tasks` | List all tasks (optionally filtered by goal) | Yes |
+| POST | `/api/tasks` | Create new task | Yes |
+| PUT | `/api/tasks/<task_id>` | Update task | Yes |
+| DELETE | `/api/tasks/<task_id>` | Delete task | Yes |
+| PATCH | `/api/tasks/<task_id>/status` | Update task status | Yes |
+| PATCH | `/api/tasks/<task_id>/order` | Update task order | Yes |
+
+**GET /api/tasks**
+- Query params: `?goal_id=<int>` (optional filter)
+- Response: `[ { task objects } ]`
+- Sorting: Unfinished by `order` ASC, finished by `finished_time` DESC
+
+**POST /api/tasks**
+- Request: `{ "goal_id": int, "title": str, "desc": str (optional) }`
+- Response: `{ "success": bool, "task_id": int, "message": str }`
+- Validation: goal_id must belong to current user and be activated
+
+**PUT /api/tasks/<task_id>**
+- Request: `{ "title": str, "desc": str }`
+- Response: `{ "success": bool, "message": str }`
+
+**DELETE /api/tasks/<task_id>**
+- Response: `{ "success": bool, "message": str }`
+
+**PATCH /api/tasks/<task_id>/status**
+- Request: `{ "status": "todo" | "doing" | "pending" | "done" }`
+- Response: `{ "success": bool, "message": str }`
+- Business logic:
+  - If status="doing": Check no other "doing" task exists for this goal
+  - If status="done": Set `finished_time` to current timestamp
+  - If status changed from "done" to other: Set `finished_time` to null
+
+**PATCH /api/tasks/<task_id>/order**
+- Request: `{ "order": float }`
+- Response: `{ "success": bool, "message": str }`
+- Note: Used for drag-and-drop reordering
+
+### 4.4 Admin
+
+| Method | Endpoint | Description | Auth Required |
+|--------|----------|-------------|---------------|
+| GET | `/api/admin/users` | List all users | Yes (admin) |
+| PUT | `/api/admin/users/<user_id>` | Update user settings | Yes (admin) |
+
+**GET /api/admin/users**
+- Response: `[ { user_id, username, role, max_goals } ]`
+
+**PUT /api/admin/users/<user_id>**
+- Request: `{ "max_goals": int, "role": str (optional) }`
+- Response: `{ "success": bool, "message": str }`
+
+## 5. Frontend Components
+
+### 5.1 Page: Login (`/login`)
+
+**Components:**
+- Username input field
+- Password input field
+- Login button
+- Link to registration page
+
+**Flow:**
+1. User enters credentials
+2. POST to `/api/auth/login`
+3. On success: redirect to `/goals`
+4. On failure: show error message
+
+### 5.2 Page: Register (`/register`)
+
+**Components:**
+- Username input field
+- Password input field
+- Confirm password input field
+- Register button
+- Link to login page
+
+**Flow:**
+1. User enters credentials
+2. POST to `/api/auth/register`
+3. On success: auto-login and redirect to `/goals`
+4. On failure: show error message
+
+### 5.3 Page: Goals (`/goals`)
+
+**Layout:**
+```
++------------------------------------------+
+| Navigation: [Goals] [Tasks] [Logout]     |
++------------------------------------------+
+| [Create Goal Button]                     |
++------------------------------------------+
+| Goal List:                               |
+| +--------------------------------------+ |
+| | Goal Title          | [Activate/Deactivate] |
+| |                     | [Edit] [Delete]  | |
+| +--------------------------------------+ |
+| | Goal Title          | [Activate/Deactivate] |
+| |                     | [Edit] [Delete]  | |
+| +--------------------------------------+ |
++------------------------------------------+
+```
+
+**Components:**
+- Goal list (table or card layout)
+- Create goal modal/form
+- Edit goal modal/form
+- Activate/Deactivate toggle button
+- Delete confirmation dialog
+
+**Interactions:**
+- Click "Create Goal" → opens modal → submit → refresh list
+- Click "Edit" → opens modal with pre-filled data → submit → refresh
+- Click toggle → PATCH request → update UI
+- Click "Delete" → confirmation → DELETE request → refresh
+
+### 5.4 Page: Tasks (`/tasks`)
+
+**Layout:**
+```
++--------------------------------------------------+
+| Navigation: [Goals] [Tasks] [Logout]             |
++--------------------------------------------------+
+| Goal Selector: [Dropdown of activated goals]     |
++--------------------------------------------------+
+| Task Scroll View (Time Picker Style):            |
+|                                                  |
+|   +---------------------------+                  |
+|   | Task N-2 (todo)           |  [faded]         |
+|   +---------------------------+                  |
+|   | Task N-1 (todo)           |  [dimmed]        |
+|   +---------------------------+                  |
+|   | >>> Task N (doing) <<<    |  [HIGHLIGHTED]   |
+|   +---------------------------+                  |
+|   | Task N+1 (todo)           |  [normal]        |
+|   +---------------------------+                  |
+|   | Task N+2 (todo)           |  [faded]         |
+|   +---------------------------+                  |
+|                                                  |
+| [Create Task Button]                             |
++--------------------------------------------------+
+| Side Panel (when task selected):                 |
+| +----------------------------------------------+ |
+| | Task Title: [____________]                   | |
+| | Description: [____________]                  | |
+| | Status: [Dropdown: todo/doing/pending/done]  | |
+| | [Save] [Delete]                              | |
+| +----------------------------------------------+ |
++--------------------------------------------------+
+```
+
+**Components:**
+- Goal selector dropdown (filters tasks by selected goal)
+- Scroll view container with centered focus area
+- Task items (draggable for unfinished tasks)
+- Create task modal/form
+- Side panel for task editing
+- Status change buttons
+
+**Scroll View Implementation:**
+- Container with `overflow-y: auto`
+- Center item highlighted with CSS
+- Scroll to center the "doing" task on load
+- Use SortableJS for drag-and-drop reordering
+- Only unfinished tasks are draggable
+- Finished tasks shown in separate section below (ordered by finished_time)
+
+**Drag-and-Drop Flow:**
+1. User drags task item
+2. SortableJS handles reordering
+3. On drop: calculate new `order` value
+4. PATCH `/api/tasks/<task_id>/order`
+5. Update local state
+
+**Side Panel Flow:**
+1. User clicks task item
+2. Side panel slides in from right
+3. Panel shows editable fields
+4. User modifies and clicks "Save"
+5. PUT request to update task
+6. Panel closes or stays open for further edits
+
+## 6. Authentication & Session Management
+
+### 6.1 Session Storage
+- Use Flask's built-in session management
+- Store `user_id` and `username` in session
+- Session cookie is HTTP-only and secure
+
+### 6.2 Password Handling
+- Hash passwords with bcrypt before storage
+- Verify passwords with bcrypt.checkpw()
+- Never store plain text passwords
+
+### 6.3 Middleware
+- `@login_required` decorator for protected routes
+- `@admin_required` decorator for admin routes
+- Check user ownership on goal/task operations
+
+## 7. Business Logic Implementation
+
+### 7.1 Goal Limit Enforcement
+```python
+def can_create_goal(user_id):
+    user = get_user(user_id)
+    goal_count = count_goals_by_user(user_id)
+    return goal_count < user.max_goals
+```
+
+### 7.2 Focus Rule Enforcement
+```python
+def set_task_to_doing(task_id, goal_id):
+    # Check if another task is already "doing"
+    doing_task = find_task(goal_id, status="doing")
+    if doing_task and doing_task.task_id != task_id:
+        # Optionally auto-change old doing to todo
+        update_task_status(doing_task.task_id, "todo")
+    
+    update_task_status(task_id, "doing")
+```
+
+### 7.3 Task Ordering
+```python
+# Unfinished tasks: ordered by 'order' field (ascending)
+# Finished tasks: ordered by 'finished_time' (descending)
+
+def get_tasks_for_goal(goal_id):
+    unfinished = query(status != "done").order_by("order")
+    finished = query(status == "done").order_by("finished_time", reverse=True)
+    return unfinished + finished
+```
+
+### 7.4 Drag-and-Drop Order Calculation
+```python
+def reorder_task(task_id, new_position, siblings):
+    # Use real numbers to avoid reordering all tasks
+    prev_order = siblings[new_position - 1].order if new_position > 0 else 0
+    next_order = siblings[new_position + 1].order if new_position < len(siblings) - 1 else prev_order + 2
+    new_order = (prev_order + next_order) / 2
+    update_task_order(task_id, new_order)
+```
+
+## 8. Development Phases
+
+### Phase 1: Foundation (Setup & Auth)
+**Setup:**
+```bash
+uv init --no-readme
+uv add flask tinydb bcrypt
+```
+
+**Files to create:**
+- `pyproject.toml` (auto-generated by uv)
+- `uv.lock` (auto-generated by uv)
+- `config.py`
+- `database.py`
+- `auth.py`
+- `app.py` (basic setup)
+- `templates/login.html`
+- `templates/register.html`
+- `static/css/style.css`
+- `static/js/api.js`
+- `static/js/auth.js`
+
+**Deliverables:**
+- Flask app running on localhost:5000 (`uv run python app.py`)
+- User registration with validation
+- User login/logout with session management
+- Password hashing with bcrypt
+- Admin user seeded on first run
+
+### Phase 2: Goal CRUD
+**Files to create:**
+- `templates/goals.html`
+- `static/css/goals.css`
+- `static/js/goals.js`
+
+**API endpoints to implement:**
+- GET/POST/PUT/DELETE `/api/goals`
+- PATCH `/api/goals/<goal_id>/toggle`
+
+**Deliverables:**
+- Goal list page with all CRUD operations
+- Activate/deactivate toggle
+- Goal limit enforcement
+- Delete confirmation dialog
+
+### Phase 3: Task CRUD (Basic)
+**Files to create:**
+- `templates/tasks.html`
+- `static/css/tasks.css`
+- `static/js/tasks.js`
+
+**API endpoints to implement:**
+- GET/POST/PUT/DELETE `/api/tasks`
+- PATCH `/api/tasks/<task_id>/status`
+
+**Deliverables:**
+- Task list filtered by goal
+- Task creation with goal selection
+- Task editing in side panel
+- Status change with focus rule enforcement
+- Finished time tracking
+
+### Phase 4: Task Ordering & Drag-Drop
+**Files to modify:**
+- `static/js/tasks.js` (add drag-drop logic)
+- `static/css/tasks.css` (add scroll view styles)
+
+**API endpoints to implement:**
+- PATCH `/api/tasks/<task_id>/order`
+
+**Deliverables:**
+- Scroll view with centered focus
+- Highlighted "doing" task
+- Drag-and-drop reordering with SortableJS
+- Order calculation with real numbers
+- Finished tasks section (sorted by finished_time)
+
+### Phase 5: Admin Features
+**Files to create:**
+- Admin section in goals.html or separate page
+- `static/js/admin.js` (if needed)
+
+**API endpoints to implement:**
+- GET `/api/admin/users`
+- PUT `/api/admin/users/<user_id>`
+
+**Deliverables:**
+- Admin can view all users
+- Admin can modify user's max_goals
+- Admin can change user role
+
+### Phase 6: Polish & Testing
+**Tasks:**
+- Error handling and user feedback
+- Loading states and animations
+- Responsive design for mobile
+- Input validation on frontend
+- Edge case handling (empty states, etc.)
+- Manual testing of all flows
+
+## 9. Configuration (config.py)
+
+```python
+# Database
+DB_PATH = "data/db.json"
+
+# Default admin credentials
+DEFAULT_ADMIN_USERNAME = "admin"
+DEFAULT_ADMIN_PASSWORD = "admin123"
+
+# Default user settings
+DEFAULT_MAX_GOALS = 5
+
+# Flask
+SECRET_KEY = "your-secret-key-here"  # Change in production
+DEBUG = True
+HOST = "0.0.0.0"
+PORT = 5000
+```
+
+## 10. Error Handling
+
+### API Error Responses
+```json
+{
+  "success": false,
+  "message": "Error description",
+  "error_code": "VALIDATION_ERROR | NOT_FOUND | UNAUTHORIZED | FORBIDDEN"
+}
+```
+
+### HTTP Status Codes
+- 200: Success
+- 201: Created
+- 400: Bad Request (validation error)
+- 401: Unauthorized (not logged in)
+- 403: Forbidden (insufficient permissions)
+- 404: Not Found
+- 500: Internal Server Error
+
+## 11. Security Considerations
+
+- Password hashing with bcrypt (cost factor 12)
+- Session-based authentication with HTTP-only cookies
+- CSRF protection (Flask-WTF or manual token)
+- Input sanitization (prevent XSS)
+- SQL injection not applicable (TinyDB), but validate all inputs
+- Rate limiting on auth endpoints (optional)
+- HTTPS in production
+
+## 12. Future Enhancements (Out of Scope)
+
+- Task categories/tags
+- Task priority levels
+- Task search and filtering
+- Export/import data
+- Email notifications
+- Task templates
+- Progress tracking per goal
+- Mobile app
diff --git a/devdocs/v1/PRD.md b/devdocs/v1/PRD.md
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+
+
+
+
+Task Table:
+
+- task_id: primary key
+- title: str (required, non-empty)
+- desc: str (optional, can be empty)
+- status: enum{todo, doing, pending, done}
+- goal_id: foreign key to goal table (required, each task belongs to exactly one goal)
+- start_time: timestamp or None
+- finished_time: timestamp or None
+- order: float (for ordering unfinished tasks)
+
+Goal Table:
+
+- goal_id: primary key
+- title: str (required, non-empty)
+- activated: bool (deactivated goals and their tasks are hidden from Task Page GUI)
+
+User Table:
+
+- user_id: primary key
+- username: str (unique, required)
+- password_hash: str (required)
+- role: enum{user, admin} (admin can configure goal limits)
+- max_goals: int (maximum goals this user can create, configurable by admin)
+
+
+GUI:
+
+Page 1. Goal CRUD
+- List all goals with activate/deactivate toggle
+- Create, edit, delete goals
+- Shows goal title and activation status
+
+Page 2. Task CRUD
+- Tasks are grouped by their parent goal
+- Only activated goals and their tasks are visible
+- Focus Rule: Each goal highlights its single "doing" task prominently
+- Scroll View: Tasks displayed in a scrollable selector (like time picker widget)
+  - Center/focus area shows current task
+  - Unfinished tasks ordered by `order` field
+  - Finished tasks ordered by `finished_time` (most recent first)
+  - Drag-and-drop reordering for unfinished tasks
+- Side Panel: Clicking a task opens a side panel for editing task details
+- Task status transitions:
+  - User manually switches task to "doing" (only one per goal)
+  - When "doing" task is completed, status becomes "done" (no auto-promotion)
+  - User must manually set next task to "doing"
+
+
+Constraints:
+
+1. **Focus Rule**: Under each goal, there should be only one "doing" task. The GUI must visually emphasize the "doing" task for each goal.
+
+2. **Ordering Rule**: 
+   - Finished tasks are ordered by `finished_time` (descending)
+   - Unfinished tasks are ordered by `order` field (ascending)
+   - Users can reorder unfinished tasks via drag-and-drop
+
+3. **Scroll View**: Tasks are displayed in a linear scroll view selector (similar to HH:mm time picker). The current task is centered/focused. Users can drag-and-drop to reorder future tasks.
+
+4. **Task-Good Relationship**: Tasks cannot exist without a goal. Each task belongs to exactly one goal.
+
+5. **Goal Limit**: Each user can only create up to their `max_goals` limit. Admin can modify this limit per user.
+
+6. **Visibility**: Deactivated goals and all their tasks are hidden from the Task Page.
+
+
+Business Rules:
+
+- Task title is required and cannot be empty
+- Goal title is required and cannot be empty
+- Tasks can be deleted (order values don't need to be continuous)
+- Goals can be activated/deactivated (only affects GUI visibility)
+- Only one "doing" task per goal at any time
+- Users must manually set a task to "doing" status
+- Simple user registration with username/password
+
+
+Tech Stack:
+
+- Backend: Python + Flask (lightweight, good for small apps)
+- Frontend: Vanilla JS + HTML/CSS (simple, no build step needed)
+- Database: TinyDB (single JSON file, perfect for this scale)
+- Authentication: Session-based with password hashing (bcrypt)
+- Drag-and-drop: HTML5 Drag and Drop API or SortableJS
+
+
+Multi-User Features:
+
+- User registration and login
+- Each user has isolated goals and tasks
+- Admin user can:
+  - Configure `max_goals_per_user` limit
+  - View all users (optional)
+- Regular users can only see/manage their own data
\ No newline at end of file