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+---
+phase: 32
+slug: setup-sharing-system
+status: approved
+shadcn_initialized: false
+preset: none
+created: 2026-04-13
+---
+
+# Phase 32 — UI Design Contract
+
+> Visual and interaction contract for the Setup Sharing System. Covers share button, share modal, visibility picker, and shared setup viewer.
+
+---
+
+## Design System
+
+| Property | Value |
+|----------|-------|
+| Tool | none |
+| Preset | not applicable |
+| Component library | none (custom Tailwind components) |
+| Icon library | Lucide via `LucideIcon` component from `lib/iconData` |
+| Font | System font stack (inherited from existing app) |
+
+---
+
+## Spacing Scale
+
+Declared values (must be multiples of 4):
+
+| Token | Value | Usage |
+|-------|-------|-------|
+| xs | 4px | Icon gaps, inline padding |
+| sm | 8px | Compact element spacing, gap-2 |
+| md | 16px | Default element spacing, gap-4, p-4 |
+| lg | 24px | Section padding, p-6 |
+| xl | 32px | Layout gaps |
+| 2xl | 48px | Major section breaks |
+| 3xl | 64px | Page-level spacing |
+
+Exceptions: none
+
+---
+
+## Typography
+
+| Role | Size | Weight | Line Height |
+|------|------|--------|-------------|
+| Body | 14px (text-sm) | 400 | 1.5 |
+| Label | 14px (text-sm) | 500 (font-medium) | 1.5 |
+| Heading | 16px (text-base) | 600 (font-semibold) | 1.5 |
+| Display | 20px (text-xl) | 600 (font-semibold) | 1.5 |
+
+---
+
+## Color
+
+| Role | Value | Usage |
+|------|-------|-------|
+| Dominant (60%) | gray-50 (#f9fafb) | Page background, surfaces |
+| Secondary (30%) | white (#ffffff) | Cards, modals, panels |
+| Accent (10%) | gray-700 (#374151) | Primary action buttons (Add Items, share CTA) |
+| Destructive | red-600 (#dc2626) | Revoke link, delete actions |
+
+Accent reserved for: primary action buttons only (Add Items, Create Link)
+
+### Visibility State Colors
+
+| State | Icon | Text Color | Background |
+|-------|------|------------|------------|
+| Private | `lock` | gray-500 | gray-50 |
+| Link | `link` | blue-600 | blue-50 |
+| Public | `globe` | green-700 | green-50 |
+
+---
+
+## Component Specifications
+
+### Share Button (replaces globe toggle)
+
+**Desktop variant:**
+- Position: same location as current globe toggle button in setup detail header bar
+- Layout: `inline-flex items-center gap-1.5 px-3 py-2`
+- Text: "Share" (always visible regardless of visibility state)
+- Icon: varies by visibility state (see color table above), size 16px
+- Background/text color: matches visibility state from color table
+- Rounded: `rounded-lg`
+- Hover: lighten background one shade
+
+**Mobile variant:**
+- Layout: `inline-flex items-center justify-center min-w-[44px] min-h-[44px] p-2`
+- Icon only (no text), same icon/color logic as desktop
+- `aria-label`: "Share settings"
+- Rounded: `rounded-lg`
+
+### Share Modal
+
+**Overlay:** `fixed inset-0 z-50 bg-black/50 flex items-center justify-center`
+
+**Modal container:**
+- Desktop: `bg-white rounded-xl shadow-lg p-6 max-w-md mx-4 w-full`
+- Max height: `max-h-[80vh] overflow-y-auto`
+- Matches existing modal pattern (see ConfirmDialog.tsx, CreateThreadModal.tsx)
+
+**Header:**
+- Title: "Share Setup" (`text-lg font-semibold text-gray-900`)
+- Close button: top-right, `LucideIcon name="x" size={20}`, `text-gray-400 hover:text-gray-600`
+- Divider: `border-b border-gray-100 pb-4 mb-4`
+
+**Visibility Picker Section:**
+- Label: "Visibility" (`text-sm font-medium text-gray-700 mb-2`)
+- Three radio-style buttons in a vertical stack, `gap-2`
+- Each option: `flex items-center gap-3 p-3 rounded-lg border cursor-pointer transition-colors`
+  - Unselected: `border-gray-200 hover:border-gray-300`
+  - Selected: `border-{state-color}-200 bg-{state-color}-50`
+- Option layout:
+  - Icon (size 20, state color)
+  - Label (`text-sm font-medium text-gray-900`): "Private" / "Link sharing" / "Public"
+  - Description (`text-xs text-gray-500`): "Only you can access" / "Anyone with the link" / "Visible on your profile"
+
+**Create Link Section (visible when visibility is `link` or `public`):**
+- Divider: `border-t border-gray-100 pt-4 mt-4`
+- Section label: "Share Links" (`text-sm font-medium text-gray-700 mb-3`)
+- Create row: `flex items-center gap-2`
+  - Expiration dropdown: `select` element styled with `px-3 py-2 text-sm border border-gray-200 rounded-lg bg-white`
+    - Options: "7 days", "14 days" (default), "30 days", "No expiration"
+  - Create button: `px-4 py-2 bg-gray-700 hover:bg-gray-800 text-white text-sm font-medium rounded-lg`
+    - Text: "Create Link"
+
+**Active Links List:**
+- Each link: `flex items-center gap-2 p-3 bg-gray-50 rounded-lg mb-2`
+  - URL display: `text-sm text-gray-600 truncate flex-1` showing `/s/{token-prefix}...`
+  - Expiration badge: `text-xs text-gray-400` showing "Expires {date}" or "No expiration"
+  - Copy button: `p-1.5 text-gray-400 hover:text-gray-600 rounded` with `LucideIcon name="copy" size={16}`
+    - After copy: icon changes to `check` with `text-green-500` for 2 seconds
+  - Revoke button: `p-1.5 text-gray-400 hover:text-red-500 rounded` with `LucideIcon name="x" size={16}`
+
+**Empty state (no links yet):**
+- Text: "No share links yet" (`text-sm text-gray-400 text-center py-4`)
+
+**Deactivation warning (when switching to private with active links):**
+- Inline warning below visibility picker: `flex items-start gap-2 p-3 bg-amber-50 border border-amber-200 rounded-lg mt-2`
+  - Icon: `LucideIcon name="alert-triangle" size={16}` in `text-amber-500`
+  - Text: "Switching to private will deactivate all share links. They can be reactivated by switching back." (`text-sm text-amber-700`)
+
+### Shared Setup Viewer
+
+**Route:** `/setups/:setupId?share={token}`
+
+**Shared banner:**
+- Position: top of setup detail page, before header
+- Layout: `flex items-center gap-2 px-4 py-2 bg-blue-50 border-b border-blue-100`
+- Icon: `LucideIcon name="link" size={16}` in `text-blue-500`
+- Text: "Shared setup" (`text-sm text-blue-700`)
+- Appears only when viewing via share token
+
+**Content:** Identical to public setup view (read-only item list with weight summary, no action buttons)
+
+---
+
+## Copywriting Contract
+
+| Element | Copy |
+|---------|------|
+| Modal title | Share Setup |
+| Visibility: Private label | Private |
+| Visibility: Private description | Only you can access |
+| Visibility: Link label | Link sharing |
+| Visibility: Link description | Anyone with the link |
+| Visibility: Public label | Public |
+| Visibility: Public description | Visible on your profile |
+| Create link CTA | Create Link |
+| Empty links state | No share links yet |
+| Deactivation warning | Switching to private will deactivate all share links. They can be reactivated by switching back. |
+| Copy success toast | Link copied |
+| Revoke confirmation | Revoke this share link? |
+| Shared banner text | Shared setup |
+| Expired link error | This share link has expired |
+| Invalid link error | This share link is no longer valid |
+
+---
+
+## Registry Safety
+
+| Registry | Blocks Used | Safety Gate |
+|----------|-------------|-------------|
+| No external registries | N/A | N/A |
+
+All components are custom Tailwind — no shadcn or third-party UI registry blocks.
+
+---
+
+## Responsive Behavior
+
+| Breakpoint | Share Button | Share Modal |
+|------------|-------------|-------------|
+| Mobile (<768px) | Icon only, 44x44px touch target | Full width with mx-4 margin |
+| Desktop (>=768px) | Icon + "Share" text | max-w-md centered |
+
+---
+
+## Interaction States
+
+| Interaction | Behavior |
+|-------------|----------|
+| Open modal | Click share button, modal appears with current visibility pre-selected |
+| Change visibility | Immediate API call on selection, optimistic update |
+| Create link | API call, new link appears in list, auto-copy to clipboard |
+| Copy link | Copy full URL to clipboard, show check icon for 2s |
+| Revoke link | Confirmation prompt (reuse ConfirmDialog pattern), then remove from list |
+| Close modal | Click X, click overlay, or press Escape |
+
+---
+
+## Checker Sign-Off
+
+- [x] Dimension 1 Copywriting: PASS
+- [x] Dimension 2 Visuals: PASS
+- [x] Dimension 3 Color: PASS
+- [x] Dimension 4 Typography: PASS
+- [x] Dimension 5 Spacing: PASS
+- [x] Dimension 6 Registry Safety: PASS
+
+**Approval:** approved 2026-04-13