```html Kanban Board

✦ Kanban Board

Drag & drop your tasks • Click to edit • Celebrate completion

``` This is a complete, self-contained Kanban board in a single HTML file. Here's a summary of what's included: ### Features - **4 columns**: Backlog, In Progress, Review, Done — each with distinct header accent colors and icons - **Drag & drop**: Cards can be dragged between columns using the native HTML5 Drag and Drop API - **Inline editing**: Double-click any card title to edit it in place (Enter to commit, Escape to cancel) - **Persistence**: All state is saved to `localStorage` under the namespace `kanban-board-v1__cards` - **Deletion**: Custom modal dialog (no `window.confirm`) with a smooth exit animation - **Add card**: Each column has an "Add card" button that reveals an inline input (Enter to commit) - **Confetti**: A custom particle-based confetti animation triggers when a card is dropped into "Done" - **Dummy data**: 7 sample cards are auto-created on first load - **No `window.alert`/`window.prompt`**: All interactions use custom UI elements ### Design - Dark theme with vibrant gradient accents - Glassmorphism-style columns with backdrop blur - Gradient accent bars on each card - Smooth CSS transitions and keyframe animations - Responsive horizontal scrolling layout - Custom scrollbar styling ### Test Selectors (all present) | Selector | Purpose | |---|---| | `data-testid="column-backlog"` | Backlog column | | `data-testid="column-in-progress"` | In Progress column | | `data-testid="column-review"` | Review column | | `data-testid="column-done"` | Done column | | `data-testid="add-card"` | Add card button (×4) | | `data-testid="card"` | Every card element | | `data-testid="delete-card"` | Delete button inside each card | | `data-testid="confirm-delete"` | Confirm button in delete modal | | `data-testid="card-input"` | Input for new/edited card titles |