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+# Phase 2B: Form Layout (Fullscreen Login)
+
+**Date:** 2026-05-02
+**Status:** Spec, awaiting review
+**Surface:** Browser extension fullscreen vault UI (`extension/src/vault/`)
+**Parent spec:** `docs/superpowers/specs/2026-04-30-relicario-fullscreen-ux-redesign-design.md` (Section A)
+
+## Goal
+
+Give the fullscreen login form a desktop-class layout: two-column field arrangement, sticky save bar, and a header that reflects dirty state and save shortcut. Other item types stay single-column for now.
+
+## Non-goals
+
+- Two-column layout for `secure_note`, `identity`, `card`, `key`, `totp`, `document` — single-column stays.
+- Popup form changes — popup keeps its existing single-column layout.
+- New affordances — Phase 2A already shipped the 8 smart inputs.
+- Three-pane shell, keyboard nav, command palette — deferred to Phase 3.
+
+## Layout
+
+### Two-column grid (login only)
+
+```
+┌────────────────────────────────────────────────────────────┐
+│ ◀ new login                              ⌘+S to save       │
+│ unsaved · esc to cancel                                    │
+├──────────────────────────┬─────────────────────────────────┤
+│ IDENTITY                 │ CREDENTIALS                     │
+│   title  [required]      │   username                      │
+│   url + ⤓                │   password ⊙ ↻                  │
+│   group (autocomplete)   │     strength: ████░             │
+│                          │   totp secret ◫                 │
+│                          │     live: 492 837 · 23s         │
+├──────────────────────────┴─────────────────────────────────┤
+│ NOTES                                                       │
+│ ▾ custom sections    ▸ attachments                          │
+├────────────────────────────────────────────────────────────┤
+│  STICKY SAVE BAR              [cancel] [save]              │
+└────────────────────────────────────────────────────────────┘
+```
+
+### CSS rules
+
+- Form pane content: `max-width: 960px`, `margin: 0 auto`.
+- Two-column wrapper: `display: grid; grid-template-columns: 1fr 1fr; gap: 24px;`.
+- Below 720px viewport: `grid-template-columns: 1fr` (single column stack). Use a single `@media (max-width: 720px)` query.
+- Notes / custom sections / attachments live in a sibling block below the grid, full-width.
+
+### Column assignment (login)
+
+**Left column — IDENTITY:**
+- title (required pill)
+- url + `⤓` fill-from-tab button + hostname chip below
+- group input + datalist autocomplete
+
+**Right column — CREDENTIALS:**
+- username
+- password + `⊙` reveal + `↻` generate; strength bar renders directly below the input
+- totp secret + `◫` QR button; live preview renders directly below the input
+
+**Full-width below grid:**
+- notes (with `≡` mono toggle)
+- custom sections / fields disclosure
+- attachments disclosure
+
+The strength bar and TOTP preview already render inline in Phase 2A — no changes needed beyond ensuring they fit within the column width.
+
+### Section headers
+
+Each column gets a small uppercase section header per the parent spec's typography rules:
+- `text-transform: uppercase; letter-spacing: 1px; font-weight: 500;`
+- 1px bottom border in `var(--border-subtle)`.
+- Color: `var(--text-muted)`.
+
+## Sticky save bar
+
+- Position: `sticky; bottom: 0;` inside the form pane's scroll container.
+- Background: `var(--bg-pane)` with a 24px gradient fade above (`linear-gradient(to top, var(--bg-pane) 60%, transparent)`).
+- Content: right-aligned `[cancel] [save]` buttons with 12px gap.
+- The save button reflects validity state — disabled when required fields are empty.
+- z-index: above form content, below modals/toasts.
+
+The fade ensures content scrolling behind the bar stays visible without a hard cutoff.
+
+## Header treatment
+
+- Title (left): `new login` or `edit login`, body font, weight 500, size 18px.
+- Subtitle (left, below title): one of:
+  - `unsaved · esc to cancel` when dirty
+  - `no changes` when pristine
+  - color: `var(--text-muted)`, size 12px.
+- Hint (right): `⌘+S to save` (visual only, not a button), `var(--text-dim)`, size 12px. On non-mac, render `Ctrl+S`.
+- Popout-to-tab `⤴` button: removed from fullscreen header (already done in Phase 1 visual baseline).
+
+The dirty/pristine state is tracked by existing form state. Phase 2B adds a small subscriber that updates the subtitle text on each input change. No new state machine — just a derived boolean.
+
+## Other item types
+
+Single-column layout stays for `secure_note`, `identity`, `card`, `key`, `totp`, `document`. These types still get the new sticky save bar and header treatment. Only the column grid is login-specific.
+
+## Files touched
+
+| File | Change |
+|------|--------|
+| `extension/src/vault/vault.css` | Add `.form-grid`, `.form-section-header`, `.sticky-save-bar`, `.form-header` styles + 720px media query |
+| `extension/src/popup/components/types/login.ts` | Wrap fields into Identity / Credentials column wrappers when rendered into the fullscreen surface |
+| `extension/src/vault/vault.ts` | Wire dirty-state subscriber to header subtitle; render header treatment + sticky bar |
+| `extension/src/vault/__tests__/` | Tests for two-column rendering, dirty subtitle transitions, sticky bar visibility |
+
+The login renderer needs to know which surface it's rendering into (popup vs fullscreen). The simplest approach: add an optional `surface: 'popup' | 'fullscreen'` parameter to `renderForm()`. Default to `popup` to preserve existing behavior.
+
+## Testing
+
+Per-area tests using existing `vitest` + `happy-dom` setup:
+
+1. **Layout test:** mount login form with `surface: 'fullscreen'`, assert grid layout is applied and Identity/Credentials columns contain the expected fields.
+2. **Stack-down test:** simulate viewport ≤720px, assert single-column layout.
+3. **Dirty subtitle test:** mount form, simulate input, assert subtitle changes from `no changes` → `unsaved · esc to cancel`. Assert reversion on reset.
+4. **Sticky bar test:** assert save bar exists, has correct position style, and save button respects validity.
+5. **Other-type non-regression:** mount `secure_note`, assert single-column layout (no grid).
+
+No e2e infrastructure changes — manual QA with the rebuilt extension loaded in Chrome.
+
+## CLI parity
+
+This phase is purely visual / layout-shaped. No CLI counterpart. The CLI already accepts all login fields as flags (`--title`, `--username`, `--password`, etc.), which is its own form surface.
+
+## Out of scope / deferred
+
+- Two-column layout for non-login types (could come in a future phase; current single-column works fine for forms with fewer fields).
+- Custom column-width adjustment by the user (drag divider). Fixed 1fr 1fr for now.
+- Animated transitions on subtitle text change (just snap).
+- Keyboard shortcut to actually save with ⌘+S — that arrives with Phase 3 keymap. The hint is purely a visual label until then.
+- Diff view ("you changed 3 fields") — future enhancement.