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+# CLAUDE.md — Action Items Prototype
+
+This file provides context for AI assistants working in this repository.
+
+## Project Overview
+
+A self-contained UI prototype for an **Action Items** management interface. The entire application lives in a single HTML file (`action-items.html`) with vanilla JavaScript and Tailwind CSS. It demonstrates 10+ variants of the same component for design review and iteration.
+
+**No build tools. No package manager. No framework.**
+
+## Repository Structure
+
+```
+playground/
+├── action-items.html    # Entire application (HTML + CSS + JS, ~1,243 lines)
+├── icons/               # SVG icons and PNG avatar images
+│   ├── *.png            # Avatars: axel.png, herbert.png, jimmy.png, john.png
+│   ├── icon-*.svg       # Custom icons (plus, trash, calendar, grip-vertical, etc.)
+│   └── tabler-icon-*.svg # Tabler icon library assets (status circles, etc.)
+└── .vscode/
+    └── launch.json      # Browse Lite debug config (launches localhost:3000)
+```
+
+## Tech Stack
+
+| Concern | Tool |
+|---|---|
+| Markup | HTML5 |
+| Styling | Tailwind CSS v3 (CDN) |
+| Logic | Vanilla ES6 JavaScript |
+| Typography | Figtree (Google Fonts CDN) |
+| Icons | Inline SVGs + Tabler Icons |
+
+No npm, no bundler, no transpiler. The file runs directly in a browser.
+
+## Running the App
+
+Serve the directory with any static HTTP server on port 3000:
+
+```bash
+# Python
+python3 -m http.server 3000
+
+# Node (npx)
+npx serve . -p 3000
+
+# VS Code: Use Browse Lite extension (pre-configured in .vscode/launch.json)
+```
+
+Then open `http://localhost:3000/action-items.html`.
+
+## Data Model
+
+```javascript
+// Single shared array — no persistence, resets on page reload
+const items = [
+  {
+    id: string,          // uid() — random alphanumeric
+    title: string,
+    description: string,
+    assignee: string | null,  // "john" | "axel" | "jimmy" | "herbert" | null
+    dueDate: string | null,   // Human-readable: "16 Mar 2026"
+    status: 'todo' | 'in_progress' | 'done' | 'not_done' | 'blocked'
+  }
+];
+```
+
+## Architecture
+
+The app is a single render loop with no virtual DOM:
+
+1. **State** lives in the `items` array (module-level)
+2. **`render()`** is called after every state mutation — it replaces `innerHTML` of each section container
+3. **Event delegation** handles clicks on dynamically generated elements
+4. **Scroll position** is preserved across re-renders manually
+
+### Key Functions
+
+| Function | Purpose |
+|---|---|
+| `render()` | Master render — rebuilds all 10 sections |
+| `renderDisplayRow(item, variant)` | Read-only row (variants: `tooltip`, `expandable`, `visible`) |
+| `renderEditableDropdownRow(item, variant)` | Row with inline pill dropdowns for editing |
+| `renderInlinePillRow(item, variant, options)` | Presentable (read-only) pill row |
+| `renderEditForm(item)` | Full edit form (title, description, assignee, due date) |
+| `renderMyActionItemsPanel()` | Floating sidebar panel |
+| `startEdit(id, section)` | Swap row → edit form in place |
+| `saveEdit(rowEl, id)` | Read form values → update items → render |
+| `removeItem(id)` | Delete from array → render |
+| `getDueDateTier(dueDateStr)` | Returns `'grey'` (>14d), `'orange'` (7–14d), or `'red'` (<7d) |
+| `moveItemBefore(dragId, targetId)` | Reorder items for drag-and-drop |
+| `escapeHtml(s)` | XSS prevention — always use when rendering user input |
+| `uid()` | Generates random IDs for new items |
+
+## Sections
+
+The page renders 11 sections, each showing a different UI variant:
+
+| Section | Variant | Description |
+|---|---|---|
+| 1 | tooltip | Editable rows — assignee/status shown on hover tooltip |
+| 2 | expandable | Editable rows — expand to reveal pills |
+| 3 | visible | Editable rows — pills always visible |
+| 4 | tooltip | Editable rows + dropdown pill editing on click |
+| 5 | expandable | Same with expandable pill visibility |
+| 6 | visible | Same with always-visible pills |
+| 7 | tooltip | Presentable (read-only) — tooltip variant |
+| 8 | expandable | Presentable — expandable variant |
+| 9 | visible | Presentable — visible variant |
+| 10 | (color-coded) | Editable with color-coded due date pills |
+| 11 | (table) | Projects and tasks table layout |
+
+## Conventions
+
+### Naming
+- **CSS classes**: hyphen-case descriptive names (`action-item-row`, `due-pill-orange`)
+- **DOM selectors**: `$` prefix for variables holding elements (`$listTooltip`, `$myItemsToggle`)
+- **Data attributes**: `data-section`, `data-id`, `data-assignee`, `data-status`
+- **Functions**: camelCase, verb-first (`renderEditForm`, `saveEdit`, `startEdit`)
+
+### DOM Patterns
+- Use `escapeHtml()` for all user-generated content rendered into innerHTML
+- Preserve scroll position by saving/restoring `scrollTop` before/after `render()`
+- Toggle visibility with Tailwind's `hidden` class or custom `.is-visible`
+- Close open dropdowns by removing `.is-open` from siblings before opening a new one
+
+### Color Palette
+| Token | Hex | Usage |
+|---|---|---|
+| Background | `#f8f9fb` | Page and card backgrounds |
+| Border | `#eaecf0` | Dividers, input borders |
+| Text primary | `#404252` | Main content |
+| Text secondary | `#777986` | Labels, hints |
+| Accent blue | `#2e6fe3` | CTAs, links |
+| Error red | `#F62020` | Destructive actions, overdue |
+| Warning orange | `#FF9E0D` | Due-soon indicators |
+
+### Due Date Tiers (getDueDateTier)
+- **Grey**: more than 14 days away (or no date)
+- **Orange**: 7–14 days away
+- **Red**: fewer than 7 days away (or overdue)
+
+## Assignees
+
+Four hardcoded users — no backend:
+
+| Key | Display Name | Avatar |
+|---|---|---|
+| `john` | John Dope | `icons/john.png` |
+| `axel` | Axel Rose | `icons/axel.png` |
+| `jimmy` | Jimmy Two | `icons/jimmy.png` |
+| `herbert` | Herbert Smith | `icons/herbert.png` |
+
+## Development Guidelines for AI Assistants
+
+1. **Keep logic in the appropriate component file.** `action-items.html` is a component catalogue — it lists components, shows each component rendered, and includes an example of its usage in a layout as a subpage. When adding or modifying a component, edit its dedicated file, not the catalogue page itself.
+2. **Always call `render()` after mutating `items`.** Forgetting this leaves the UI out of sync.
+3. **Use `escapeHtml()` for any user-provided strings** inserted via `innerHTML`.
+4. **Preserve scroll position** around `render()` calls that might shift content.
+5. **Close sibling dropdowns** before opening a new one to avoid multiple open dropdowns.
+6. **Test all 10+ sections** after UI changes — each section renders independently and a change to a shared helper affects all of them.
+7. **No persistence** — `items` is in-memory only. Refreshing the page resets to sample data.
+8. **Icon assets are in `icons/`** — reference them with relative paths (`icons/icon-plus.svg`).
+9. **Tailwind is from CDN** — use utility classes directly; no Tailwind config file exists.
+10. **Date format is `"DD Mon YYYY"`** (e.g., `"16 Mar 2026"`) — match this exactly when generating or parsing dates.
+
+## No Tests, No CI
+
+There is no test suite and no CI/CD pipeline. Verification is manual — open the HTML file in a browser and exercise the UI.