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+# v0.2.1 — Polish, Icons, Cut Clip & Shortcuts Reference
+
+## Overview
+
+Incremental polish release building on v0.2.0 Player mode. Six changes: controls position tweak, Lucide icon migration, blur animation fix, mode toggle shortcuts, cut-clip feature, and keyboard shortcuts reference in the About dialog.
+
+---
+
+## 1. Floating Controls Position & Blur Fix
+
+### Position
+
+Raise `.player-controls-overlay` from `bottom: 48px` to `bottom: 64px` (+16px).
+
+### Blur Pop-in Fix
+
+**Problem:** `backdrop-filter: blur(8px)` is on `.player-controls-panel` while the parent `.player-controls-overlay` transitions `opacity: 0 → 1`. WebKit doesn't smoothly composite `backdrop-filter` through an ancestor `opacity` transition — the blur snaps on once opacity crosses a rendering threshold.
+
+**Fix:** Move the blur background into a `::before` pseudo-element on `.player-controls-panel`. The pseudo-element handles `background` + `backdrop-filter` and has its own `opacity` transition driven by the `.visible` class on the overlay ancestor. The panel itself becomes `position: relative` with no background/backdrop-filter of its own.
+
+```css
+.player-controls-panel {
+  position: relative;
+  /* background and backdrop-filter removed */
+}
+
+.player-controls-panel::before {
+  content: '';
+  position: absolute;
+  inset: 0;
+  background: rgba(0, 0, 0, 0.75);
+  backdrop-filter: blur(20px);
+  -webkit-backdrop-filter: blur(20px);
+  border-radius: 12px;
+  z-index: -1;
+  opacity: 0;
+  transition: opacity 0.25s ease;
+}
+
+.player-controls-overlay.visible .player-controls-panel::before {
+  opacity: 1;
+}
+```
+
+---
+
+## 2. Lucide Icon Migration
+
+Install `lucide-svelte` as a dependency. Replace all emoji and text-glyph icons with Lucide SVG components across `PlayerControls.svelte`, `TransportControls.svelte`, and the `App.svelte` toolbar.
+
+### Icon Mapping
+
+| Current | Lucide Component | Location |
+|---|---|---|
+| 🔇 / 🔉 / 🔊 | `VolumeX` / `Volume1` / `Volume2` | PlayerControls, TransportControls |
+| ⏪ | `SkipBack` | PlayerControls |
+| ❚❚ / ▶ | `Pause` / `Play` | PlayerControls, TransportControls |
+| ⏩ | `SkipForward` | PlayerControls |
+| CC (text) | `Captions` | PlayerControls |
+| ⧉ | `PictureInPicture2` | PlayerControls |
+| ⛶ / ⤓ | `Maximize` / `Minimize` | PlayerControls |
+| ⚙ | `Settings` | App toolbar |
+| ℹ | `Info` | App toolbar |
+| ⬒ / ⬓ | `PanelLeft` / `PanelBottom` | App toolbar |
+| ✂️ (new) | `Scissors` | PlayerControls (cut clip button) |
+| ◄K / K► | `ChevronFirst` / `ChevronLast` | TransportControls |
+| ◄\| / \|► | `StepBack` / `StepForward` | TransportControls |
+
+Icons render inline as SVGs. Size: 16–18px to match existing button dimensions.
+
+---
+
+## 3. Mode Toggle Shortcuts
+
+Both `C` and `P` keys become bidirectional toggles. Pressing either key switches from the current mode to the other mode.
+
+Implementation: both the `'c'/'C'` and `'p'/'P'` cases in `handleGlobalKeydown` call `toggleMode()` instead of hard-coding a target mode via `setAppMode()`.
+
+---
+
+## 4. Cut Clip Feature
+
+### Button
+
+A scissors icon (`Scissors` from Lucide) in the `PlayerControls` right control group, positioned between the speed selector and the CC button.
+
+### Behavior
+
+- **Left-click / `X` key:** Create a 10-second clip starting at the current playhead position (`currentTime` → `currentTime + 10`). Clamp end to `session.duration`. Switch to Clipper mode. Playhead stays at its current position.
+- **Right-click / `Z` key:** Create a 10-second clip ending at the current playhead position (`currentTime - 10` → `currentTime`). Clamp start to `0`. Switch to Clipper mode. Playhead stays at its current position.
+
+### Implementation
+
+- Add a `cutClip(position: 'at' | 'before')` helper. It calls `addClip(start, end)` from the clips store, then `setAppMode('clipper')`.
+- Pass an `onCutClip` callback prop to `PlayerControls`. The button's `onclick` calls `onCutClip('at')`, `oncontextmenu` prevents default and calls `onCutClip('before')`.
+- In `handleGlobalKeydown`: `X`/`x` → `cutClip('at')`, `Z`/`z` → `cutClip('before')`. Only active in Player mode.
+- **Tooltip:** "Cut clip at playhead (X) · Right-click: 10s before (Z)"
+
+### Edge Cases
+
+- No video loaded (`session.duration === 0`): no-op.
+- Playhead < 10s from start: `Z`/right-click clamps start to 0.
+- Playhead < 10s from end: `X`/left-click clamps end to duration.
+
+---
+
+## 5. Tabbed About Dialog with Keyboard Shortcuts
+
+### Tab Structure
+
+Two tabs: **About** (default) and **Shortcuts**.
+
+### About Tab
+
+Identical to current content (icon, app name, version, author, license, repo link, close button). Dialog stays at ~360px wide.
+
+### Shortcuts Tab
+
+Two-column layout (key on left, description on right) grouped by section headers. Dialog expands to ~520px wide with `max-height: 70vh` and vertical scroll. Width change transitions smoothly (`transition: max-width 0.2s ease`).
+
+Tab switcher: text tabs at the top of the dialog, active tab gets accent-color underline.
+
+### Complete Shortcut Reference
+
+**Global (both modes):**
+
+| Key | Action |
+|---|---|
+| `Space` | Play / Pause |
+| `K` | Play / Pause |
+| `J` | Shuttle slower (−0.25×) |
+| `L` | Shuttle faster (+0.25×) |
+| `←` | Seek back 5s |
+| `→` | Seek forward 5s |
+| `Shift+←` | Seek back 1s |
+| `Shift+→` | Seek forward 1s |
+| `,` | Previous frame |
+| `.` | Next frame |
+| `<` (Shift+,) | Previous keyframe |
+| `>` (Shift+.) | Next keyframe |
+| `C` / `P` | Toggle mode |
+| `Cmd+/` | About |
+
+**Player mode:**
+
+| Key | Action |
+|---|---|
+| `F` | Toggle fullscreen |
+| `X` | Cut clip at playhead → Clipper |
+| `Z` | Cut clip 10s before playhead → Clipper |
+
+**Clipper mode:**
+
+| Key | Action |
+|---|---|
+| `I` | Set in-point |
+| `O` | Set out-point |
+| `Delete` / `Backspace` | Remove selected clip |
+| `Cmd+E` | Export |