UI overhaul "Living Codex" C+D: Lucide icons + left-rail shell

- Replace the top nav with a left rail + top context bar ("GM mission control"):
  gilt crown wordmark, nav grouped At the Table / Reference with Lucide icons and a
  gold active state (accent-glow + gilt left edge), a collapse toggle
  (uiStore.railCollapsed). A single responsive rail = icon strip (68px) on phones /
  when collapsed, full labels on >= sm.
- Top bar: campaign switcher, a ⌘K search pill, and every existing control preserved
  (PlayerSessionBadge, Session panel toggle, HandoutControl, SessionControl host,
  theme toggle as Sun/Moon, Settings) — same aria-labels/testids so e2e is intact.
- bun add lucide-react. Rail is print:hidden (sheets export clean).

223 unit + 34 e2e + 2 realtime green; nav contract (aria-label="Primary", link names) preserved.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/app/RootLayout.tsx

@@ -1,5 +1,10 @@
 import { useEffect, useRef, useState } from 'react';
 import { Link, Outlet, useRouterState } from '@tanstack/react-router';
+import {
+  Crown, LayoutDashboard, UserRound, Swords, Map as MapIcon, Dices, BookOpenText, RadioTower,
+  LibraryBig, Settings as SettingsIcon, Search, PanelLeftClose, PanelLeftOpen, Sun, Moon, PanelRight,
+  type LucideIcon,
+} from 'lucide-react';
 import { useUiStore } from '@/stores/uiStore';
 import { CommandPalette } from '@/components/CommandPalette';
 import { useActiveCampaign, useCampaigns } from '@/features/campaigns/hooks';
@@ -16,14 +21,22 @@ import { PlayerSessionBadge } from '@/features/play/PlayerConnection';
 import { SessionSidebar } from '@/features/play/SessionSidebar';
 import { useSessionStore } from '@/stores/sessionStore';
 
-const NAV = [
-  { to: '/', label: 'Campaigns', exact: true },
-  { to: '/dashboard', label: 'Dashboard', exact: false },
-  { to: '/characters', label: 'Characters', exact: false },
-  { to: '/combat', label: 'Combat', exact: false },
-  { to: '/dice', label: 'Dice', exact: false },
-  { to: '/compendium', label: 'Compendium', exact: false },
-] as const;
+type NavItem = { to: string; label: string; icon: LucideIcon; exact: boolean; group: 'top' | 'play' | 'reference' };
+const NAV: NavItem[] = [
+  { to: '/', label: 'Campaigns', icon: LibraryBig, exact: true, group: 'top' },
+  { to: '/dashboard', label: 'Dashboard', icon: LayoutDashboard, exact: false, group: 'play' },
+  { to: '/characters', label: 'Characters', icon: UserRound, exact: false, group: 'play' },
+  { to: '/combat', label: 'Combat', icon: Swords, exact: false, group: 'play' },
+  { to: '/maps', label: 'Battle Map', icon: MapIcon, exact: false, group: 'play' },
+  { to: '/dice', label: 'Dice', icon: Dices, exact: false, group: 'play' },
+  { to: '/compendium', label: 'Compendium', icon: BookOpenText, exact: false, group: 'reference' },
+  { to: '/play', label: 'Live Session', icon: RadioTower, exact: false, group: 'reference' },
+];
+const GROUPS: { id: NavItem['group']; label: string | null }[] = [
+  { id: 'top', label: null },
+  { id: 'play', label: 'At the Table' },
+  { id: 'reference', label: 'Reference' },
+];
 
 function CampaignSwitcher() {
   const campaigns = useCampaigns();
@@ -55,7 +68,7 @@ function ThemeToggle() {
   const toggle = useUiStore((s) => s.toggleTheme);
   return (
     <Button size="icon" variant="ghost" onClick={toggle} aria-label="Toggle light/dark theme" title="Toggle theme">
-      {theme === 'dark' ? '☀' : '☾'}
+      {theme === 'dark' ? <Sun size={18} aria-hidden /> : <Moon size={18} aria-hidden />}
     </Button>
   );
 }
@@ -65,6 +78,8 @@ export function RootLayout() {
   const [paletteOpen, setPaletteOpen] = useState(false);
   const sessionDockOpen = useUiStore((s) => s.sessionDockOpen);
   const setSessionDock = useUiStore((s) => s.setSessionDock);
+  const railCollapsed = useUiStore((s) => s.railCollapsed);
+  const toggleRail = useUiStore((s) => s.toggleRail);
   const sessionConnected = useSessionStore((s) => s.status === 'connected');
   const sessionRole = useSessionStore((s) => s.role);
   const joinIntent = useSessionStore((s) => s.joinIntent);
@@ -94,56 +109,120 @@ export function RootLayout() {
     }
   }, [joinIntent, sessionRole, setSessionDock]);
 
-  return (
-    <div className="flex h-full flex-col">
-      <header className="flex items-center gap-4 border-b border-line bg-panel px-4 py-2">
-        <Link to="/" className="font-display text-lg font-bold text-accent">
-          ⚔ TTRPG Manager
-        </Link>
-        <nav className="flex items-center gap-1" aria-label="Primary">
-          {NAV.map((item) => {
-            const isActive = item.exact ? pathname === item.to : pathname.startsWith(item.to);
-            return (
-              <Link
-                key={item.to}
-                to={item.to}
-                className={cn(
-                  'rounded-md px-3 py-1.5 text-sm transition-colors',
-                  isActive ? 'bg-elevated text-accent' : 'text-muted hover:text-ink hover:bg-elevated',
-                )}
-              >
-                {item.label}
-              </Link>
-            );
-          })}
-        </nav>
-        <div className="ml-auto flex items-center gap-2">
-          <PlayerSessionBadge />
-          <Button size="sm" variant="ghost" onClick={() => setSessionDock(true)} title="Session panel — who's here, rolls, chat" aria-label="Open session panel">
-            ☰ Session{sessionConnected && <span className="ml-1 inline-block h-1.5 w-1.5 rounded-full bg-success align-middle" />}
-          </Button>
-          {activeCampaign && <HandoutControl />}
-          <SessionControl />
-          <Button size="sm" variant="ghost" onClick={() => setPaletteOpen(true)} title="Command palette (Ctrl/Cmd+K)" aria-label="Open command palette">
-            ⌘K
-          </Button>
-          <Link to="/settings" className="rounded-md p-1.5 text-sm text-muted hover:text-ink" title="Settings" aria-label="Settings">⚙</Link>
-          <CampaignSwitcher />
-          <ThemeToggle />
-        </div>
-      </header>
+  // Labels show only when expanded AND on >= sm; the rail is an icon strip (68px)
+  // on phones and when collapsed, so a single nav serves every size.
+  const showLabel = !railCollapsed;
 
-      <div className="flex min-h-0 flex-1">
-        <main className="flex-1 overflow-auto">
-          <ErrorBoundary resetKey={pathname}>
-            <Outlet />
-          </ErrorBoundary>
-        </main>
-        <SessionSidebar open={sessionDockOpen} onClose={() => setSessionDock(false)} />
+  return (
+    <>
+      <div className="grid h-full grid-cols-[auto_1fr]">
+        {/* ---- Left nav rail (single, responsive: icon strip on phones / collapsed) ---- */}
+        <aside className={cn('paper-grain relative z-20 flex flex-col border-r border-line bg-panel transition-[width] duration-200 print:hidden', railCollapsed ? 'w-[68px]' : 'w-[68px] sm:w-60')}>
+          <div className="relative z-[1] flex h-full flex-col">
+            <Link to="/" className={cn('flex h-[60px] flex-none items-center gap-3 border-b border-line px-4', railCollapsed ? 'justify-center px-0' : 'justify-center px-0 sm:justify-start sm:px-4')} title="TTRPG Manager">
+              <span className="grid h-9 w-9 flex-none place-items-center rounded-lg bg-gradient-to-b from-accent-soft to-accent text-accent-ink shadow-[inset_0_1px_0_rgba(255,255,255,0.3)]">
+                <Crown size={19} strokeWidth={2} aria-hidden />
+              </span>
+              {showLabel && (
+                <span className="hidden min-w-0 leading-tight sm:block">
+                  <span className="block truncate font-display text-base font-semibold text-ink">TTRPG Manager</span>
+                  <span className="smallcaps block" style={{ fontSize: 9, letterSpacing: '0.22em' }}>The Living Codex</span>
+                </span>
+              )}
+            </Link>
+
+            <nav aria-label="Primary" className="flex-1 overflow-y-auto py-2">
+              {GROUPS.map((group) => (
+                <div key={group.id}>
+                  {group.label && showLabel && <div className="smallcaps hidden px-6 pt-4 pb-1.5 sm:block" style={{ fontSize: 9.5 }}>{group.label}</div>}
+                  {NAV.filter((n) => n.group === group.id).map((item) => {
+                    const active = item.exact ? pathname === item.to : pathname.startsWith(item.to);
+                    const Ico = item.icon;
+                    return (
+                      <Link
+                        key={item.to}
+                        to={item.to}
+                        title={item.label}
+                        className={cn(
+                          'relative mx-2.5 my-px flex h-[42px] items-center gap-3 rounded-[10px] text-[14.5px] font-medium transition-colors',
+                          'justify-center px-0',
+                          showLabel && 'sm:justify-start sm:px-3.5',
+                          active ? 'bg-accent-glow font-semibold text-accent-deep' : 'text-muted hover:bg-elevated hover:text-ink',
+                        )}
+                      >
+                        {active && <span className="absolute -left-2.5 top-2 bottom-2 w-[3px] rounded-r bg-accent" aria-hidden />}
+                        <Ico size={19} strokeWidth={active ? 2 : 1.7} aria-hidden className="flex-none" />
+                        {showLabel && <span className="hidden sm:inline">{item.label}</span>}
+                      </Link>
+                    );
+                  })}
+                </div>
+              ))}
+            </nav>
+
+            <div className="hidden flex-none border-t border-line p-2.5 sm:block">
+              <button
+                onClick={toggleRail}
+                className={cn('flex h-[42px] w-full items-center gap-3 rounded-[10px] text-[14.5px] font-medium text-muted transition-colors hover:bg-elevated hover:text-ink', railCollapsed ? 'justify-center px-0' : 'justify-start px-3.5')}
+                title={railCollapsed ? 'Expand navigation' : 'Collapse navigation'}
+                aria-label={railCollapsed ? 'Expand navigation' : 'Collapse navigation'}
+              >
+                {railCollapsed ? <PanelLeftOpen size={18} aria-hidden /> : <PanelLeftClose size={18} aria-hidden />}
+                {!railCollapsed && <span>Collapse</span>}
+              </button>
+            </div>
+          </div>
+        </aside>
+
+        {/* ---- Workarea: top context bar + canvas ---- */}
+        <div className="flex min-w-0 flex-col">
+          <header className="paper-grain relative z-10 flex h-[60px] flex-none items-center gap-2 border-b border-line bg-panel px-3 sm:px-5">
+            <div className="relative z-[1] flex w-full items-center gap-2">
+              <CampaignSwitcher />
+              <div className="flex-1" />
+
+              <button
+                onClick={() => setPaletteOpen(true)}
+                aria-label="Open command palette"
+                title="Command palette (Ctrl/Cmd+K)"
+                className="hidden h-[38px] min-w-44 items-center gap-2 rounded-full border border-line bg-surface px-3 text-muted transition-[border-color,box-shadow] hover:border-accent focus-visible:border-accent focus-visible:outline-none focus-visible:ring-[3px] focus-visible:ring-accent-glow md:flex"
+              >
+                <Search size={16} aria-hidden />
+                <span className="flex-1 text-left text-sm text-faint">Search the codex…</span>
+                <kbd className="rounded border border-line px-1.5 font-mono text-[10.5px] text-faint">⌘K</kbd>
+              </button>
+              <Button size="icon" variant="ghost" className="md:hidden" onClick={() => setPaletteOpen(true)} aria-label="Open command palette" title="Command palette">
+                <Search size={18} aria-hidden />
+              </Button>
+
+              <PlayerSessionBadge />
+              <Button size="sm" variant="subtle" onClick={() => setSessionDock(true)} title="Session panel — who's here, rolls, chat" aria-label="Open session panel">
+                <PanelRight size={15} aria-hidden />
+                <span className="hidden sm:inline">Session</span>
+                {sessionConnected && <span className="inline-block h-1.5 w-1.5 rounded-full bg-success align-middle" />}
+              </Button>
+              {activeCampaign && <HandoutControl />}
+              <SessionControl />
+              <ThemeToggle />
+              <Link to="/settings" className="grid h-9 w-9 flex-none place-items-center rounded-md text-muted hover:bg-elevated hover:text-ink" title="Settings" aria-label="Settings">
+                <SettingsIcon size={18} aria-hidden />
+              </Link>
+            </div>
+          </header>
+
+          <div className="flex min-h-0 flex-1">
+            <main className="flex-1 overflow-auto">
+              <ErrorBoundary resetKey={pathname}>
+                <Outlet />
+              </ErrorBoundary>
+            </main>
+            <SessionSidebar open={sessionDockOpen} onClose={() => setSessionDock(false)} />
+          </div>
+        </div>
       </div>
 
       <RollTray />
       {paletteOpen && <CommandPalette onClose={() => setPaletteOpen(false)} />}
-    </div>
+    </>
   );
 }