# Listing detail page — desktop/web design pass

## Problem

The listing detail screen (`app/src/app/listing/[id].tsx`) looks noticeably worse on
web/desktop than the HTML design prototype (`prototype/Volana.dc.html`, "LISTING
DETAIL" section, lines 423-543): content runs edge-to-edge with no max-width, the
hero is an oversized flat-color box with a tiny emoji, typography doesn't scale up
for desktop, the sidebar isn't visually a distinct card, and several shared
components it depends on (`TopNav`, `ListingCard`) have the same issues since they're
reused across other screens.

## Scope

Primary target: `app/src/app/listing/[id].tsx`. Because two of the fixes (navbar,
"customers also bought" cards) live in shared components also used by
`(tabs)/index.tsx`, `(tabs)/browse.tsx`, and `(tabs)/orders.tsx`, this spec also
covers:
- `app/src/components/TopNav.tsx`
- `app/src/components/ListingCard.tsx`
- `app/src/components/StatusChip.tsx`
- `app/src/components/ResolverCard.tsx`
- A new `app/src/components/PageContainer.tsx`
- `app/src/global.css` (theme)
- `app/src/app/_layout.tsx` (font loading)

Out of scope: on-chain/wallet logic, `(tabs)/index.tsx` and `(tabs)/browse.tsx`
layout beyond what `ListingCard` changes give them for free, `WalletConnectSheet`,
`CheckoutSheet`, the mobile/desktop nav breakpoint (768px) itself, nav
blur/translucency.

The prototype (`prototype/Volana.dc.html`) is the visual source of truth; it has
**zero responsive/mobile CSS** — it's a desktop-only mockup, no `@media` queries
touch layout anywhere in it. All mobile-specific sizing in this spec (hero aspect
ratio, typography minimums, the two-column breakpoint) is therefore this spec's own
design judgment, not something derived from the prototype.

## Theme (`app/src/global.css`)

Theme colors are sourced from the prototype's own CSS variables (`--c-bg`,
`--c-surf`, `--c-surf2`, `--c-a`, `--c-g`, `--c-y`, `--c-r`, defined in
`prototype/Volana.dc.html`'s `<style>` block). `app/src/global.css`'s existing
`--background`, `--surface`, `--surface-secondary`, `--accent`, `--success`,
`--warning`, `--danger` already match these values for both light and dark themes
— leave them as they are. Extend the existing `@layer theme` blocks with what's
missing:

- Add `--border` overrides (currently unset, silently falling back to HeroUI's
  generic default gray instead of the prototype's `--c-bd` border color):
  - dark: `--border: #252548`
  - light: `--border: #e2dff0`
- Add a second muted tier. The prototype uses two distinct de-emphasis levels —
  `--c-t2` for body/description text (already mapped to HeroUI's `--muted`) and a
  dimmer `--c-t3` for micro-labels, captions, wallet/listing IDs, fee fine-print
  (currently has no equivalent). Add a new semantic color following HeroUI's
  documented "Adding Custom Colors" pattern:
  ```css
  @layer theme {
    @variant dark { --subtle: #605c88; }
    @variant light { --subtle: #9991b8; }
  }
  @theme inline {
    --color-subtle: var(--subtle);
  }
  ```
  Usable as `className="text-subtle"` (Typography's `color` prop only accepts
  `default|muted`, so subtle text is applied via `className`, not the `color` prop).
- No radius changes. Base `--radius` is already `8px` → `rounded-xl` (12px) and
  `rounded-2xl` (16px) already match the spec's button/card radius targets via
  existing Tailwind utility classes; just use those classes consistently instead of
  `<Surface>`'s default `rounded-3xl` (24px).

## Fonts

The prototype loads DM Sans (body) and DM Mono (addresses, fees, IDs) from Google
Fonts; the app currently uses HeroUI's default system font throughout.

- Add `@expo-google-fonts/dm-sans` and `@expo-google-fonts/dm-mono` (both exist on
  npm, confirmed).
- Load `DMSans_400Regular`, `DMSans_500Medium`, `DMSans_600SemiBold`,
  `DMSans_700Bold`, `DMMono_400Regular`, `DMMono_500Medium` via `useFonts` in
  `app/src/app/_layout.tsx`, following the existing app-level loading-gate pattern
  (render nothing / keep splash screen until `fontsLoaded`).
- Override HeroUI's font CSS variables per its documented mechanism:
  ```css
  @theme {
    --font-normal: 'DMSans_400Regular';
    --font-medium: 'DMSans_500Medium';
    --font-semibold: 'DMSans_600SemiBold';
  }
  ```
- Monospace elements (resolver fee %, wallet addresses, listing IDs) use
  `<Typography type="code" className="bg-transparent px-0 py-0 self-auto">`
  (HeroUI's monospace preset, stripped of its default chip-style
  background/padding) with an explicit `style={{ fontFamily: 'DMMono_500Medium' }}`
  override — HeroUI's `type="code"` font selection is hardcoded to generic
  `'monospace'`/`'Menlo'` in its source (`text.constants.ts`) and isn't
  theme-variable-driven, so the loaded DM Mono font must be applied directly via
  `style` (which takes precedence over `className` per this project's styling
  conventions).

## `PageContainer` (new component)

`app/src/components/PageContainer.tsx`:
```tsx
interface PageContainerProps {
  children: ReactNode;
  className?: string;
}

export function PageContainer({ children, className }: PageContainerProps) {
  return (
    <View className={cn("w-full self-center px-4 md:px-8 lg:max-w-[1320px] lg:px-12", className)}>
      {children}
    </View>
  );
}
```
(Exact class-merge helper — `cn`/`twMerge`/plain template string — decided at
implementation time to match whatever convention the rest of the codebase uses.)

Used to wrap:
- `TopNav`'s inner content (the nav bar itself stays edge-to-edge with its
  `border-b`; only the row of logo/search/links/wallet-button inside it is
  constrained)
- The entire `ListingDetailScreen` body (hero, two-column detail layout, and
  "Customers also bought" section all inside one container, mirroring the
  prototype's single wrapping div)

## Listing detail layout (`app/src/app/listing/[id].tsx`)

**Two-column split:** change the breakpoint from `md:flex-row` (768px) to
`lg:flex-row` (1024px) so there's room for the 340px sidebar before switching to
two columns. Main content column `flex-1`, sidebar fixed `lg:w-[340px]`. Below
`lg`: single column, sidebar stacks under the hero (today's existing behavior,
just at a higher breakpoint).

**Sticky sidebar:** keep the existing web-only `position: sticky` mechanism, but
gate it behind a `useWindowDimensions` width check (same pattern
`app/src/app/(tabs)/_layout.tsx` already uses for its own breakpoint) so it only
activates at `>=1024`. Update `top` offset to match the new desktop nav height
(~76px) plus spacing (~92px total).

**Hero:**
- `style={{ aspectRatio: isWide ? 2.4 : 1.6 }}` (RN's `aspectRatio` style works
  cross-platform, no separate mobile/desktop height branches needed) — `isWide`
  reuses the same width check as the sticky sidebar.
- `rounded-2xl overflow-hidden`, background color from `listing.bg` (unchanged,
  per-listing data).
- Layered on top via `react-native-svg` (already a project dependency, no new
  install needed): a `RadialGradient` white-8%-to-transparent highlight
  (top-left-biased) and a bottom linear fade to black-transparent — replicating the
  prototype's actual two-layer gradient technique exactly.
- Emoji: `text-[96px] lg:text-[160px]`, centered.

**Typography scale** (Tailwind arbitrary values layered on HeroUI's `type` presets,
which supply weight/line-height defaults; size is overridden responsively):
- Title: `text-2xl lg:text-[38px] leading-tight font-bold`
- Description: `text-[15px] lg:text-[17px]`, `color="muted"`
- Sidebar price: `text-[30px] lg:text-[42px] font-extrabold`
- USD subline: `text-[15px] lg:text-[18px] text-subtle`
- Section micro-labels ("Pay with", "Dispute Protection", "About this listing"):
  `text-[11px] font-semibold uppercase tracking-wider text-subtle` — defined once
  as a local class-string constant in `[id].tsx` and reused at its ~4 call sites
  (not a new shared component; not reused outside this screen yet)

**Purchase sidebar card:**
- `rounded-2xl border border-border bg-surface p-6 lg:p-8`, existing `<Separator />`
  usage between price / pay-with / dispute-protection / CTA blocks, re-padded to the
  new scale.
- Stock badge uses `StatusChip`'s new `variant="outline"` (see below).
- CTA: `<Button size="lg">`, full width, `variant="primary"` (unchanged) — verify at
  implementation time that HeroUI's `lg` button size lands in the ~52-56px height
  range; adjust with `className="h-14"` only if the built-in size doesn't already
  hit it.
- Trust chips ("Final Payment", "Dispute Cover", "On-chain"):
  `<Chip size="sm" variant="secondary">` (renders `bg-default`) as the closest
  built-in equivalent to a small elevated pill.

**Verified box:** add an icon in a violet circle (`bg-accent-soft` circle,
`text-accent` `Ionicons` checkmark) to the left of the existing two-line
"Verified on Solana" / address text block; "Copy" button stays right-aligned;
address rendered with the new monospace treatment.

**About this listing:** keep the existing 2-column grid structure; apply the new
micro-label style to the small "Category"/"Available"/"Currency"/"Listing ID"
captions; bump row-gap to match the new spacing scale; Listing ID value gets the
monospace treatment.

## `StatusChip` (`app/src/components/StatusChip.tsx`)

Add an optional `variant?: "soft" | "outline"` prop, default `"soft"` (existing
behavior, unchanged call sites in `ListingCard`/`OrderRow` keep working as-is).
New `"outline"` value renders `<Chip variant="tertiary" color={color}>` plus an
explicit border className looked up from a static `Record<StatusColor, string>`
map (e.g. `{ success: "border border-success", warning: "border border-warning",
default: "border border-default", accent: "border border-accent", danger: "border
border-danger" }`) — dynamic template-literal class names
(`` `border-${color}` ``) must not be used since Uniwind/Tailwind need statically
analyzable class strings to include them in the build. Transparent background,
colored border + text, built entirely from existing Chip primitives and theme
color tokens (no new component, no hardcoded colors). Used for the sidebar's
"5 in stock" badge only.

## `ResolverCard` (`app/src/components/ResolverCard.tsx`)

- Unselected background changes from `bg-transparent` to `bg-surface-secondary`
  (was: plain transparent; prototype implies an elevated unselected state).
  Selected state (`border-accent bg-accent/10`) is unchanged.
- Add web-only hover feedback via local `onHoverIn`/`onHoverOut` state (these
  Pressable events only fire on web/mouse input and are no-ops on native touch —
  no `Platform.OS` branching required). Hover state lightens the border slightly
  using HeroUI's existing calculated `border-secondary`/`border-tertiary` tokens,
  not a new custom color.

## `TopNav` (`app/src/components/TopNav.tsx`)

- Height: `h-16 lg:h-[76px]` (was flat `h-16`).
- Content wrapped in `PageContainer` (replacing the current manual `px-6`).
- Search field width bumped: `lg:w-[480px]` (was capped at `max-w-[320px]` with no
  larger breakpoint).
- No other structural changes. The `md:flex` visibility breakpoint (mobile tab bar
  vs. desktop nav swap) is unchanged — out of scope for this spec. No
  blur/translucency backdrop — the prototype's `backdrop-filter: blur(20px)` is a
  nice-to-have on top of this navbar's core requirements (height, border, logo,
  search, links, pill, connect button), has no native equivalent, and is
  deliberately excluded to keep this scoped.

## `ListingCard` grid variant (`app/src/components/ListingCard.tsx`)

Affects "Customers also bought" on the listing detail page, and (as a side effect
of this being a shared component) the featured-listings grid on the home tab and
the grid view on the browse tab:
- Image area: `aspect-[4/3]` (was fixed `h-32`), same white-highlight radial-overlay
  technique as the hero (smaller), emoji `text-6xl lg:text-7xl` (was flat `text-4xl`).
- Grid gap bumped: `gap-5 lg:gap-6` (was tighter implicit padding via `p-1.5`).
- Title semibold (unchanged), address in the new monospace/subtle treatment, price
  in `text-accent font-bold` (unchanged), stock badge small, positioned top-right
  of the card body (was inline with price).
- Buy Now button stays `size="sm"` — already more subdued than the sidebar's `lg`
  CTA; no variant change needed.

## Cross-cutting

- Vertical spacing between major sections on the listing detail screen:
  `gap-6 lg:gap-10` (was flat `gap-5`/`gap-6` with no responsive scaling).
- Web-only hover states (resolver cards, related-product cards) via the
  `onHoverIn`/`onHoverOut` local-state pattern described above — applied
  consistently wherever this spec calls for hover feedback.
- Mobile regression check: since the two-column breakpoint moves from `md` (768px)
  to `lg` (1024px), mobile and tablet-portrait layouts stay single-column longer
  than today, which is a safe direction (less likely to cramp a mid-size viewport),
  not a regression risk in itself. Verify at implementation time on a phone-width
  viewport that spacing/typography changes don't look oversized before `lg`.

## Testing

No test runner is configured in this repo (per `CLAUDE.md`). Verification is:
`npm run typecheck`, `npm run lint`, and manual check in a running `expo start`
web session at mobile (<768px), tablet (~900px), and desktop (>=1320px) widths,
plus a native (iOS or Android simulator) pass to confirm nothing web-only leaked
into native rendering.