diff --git a/TODO.md b/TODO.md
index 8d4c007..d6e56a8 100644
--- a/TODO.md
+++ b/TODO.md
@@ -51,11 +51,11 @@ This file is the single source of truth for roadmap and delivery progress.
 
 - [x] [P1] Separate Next.js public app in monorepo
 - [x] [P1] App Router + TypeScript + `src/` structure
-- [~] [P1] Public app connected to shared data layer
-- [ ] [P1] Localized route structure and middleware rules
-- [ ] [P2] Public layout system (header/footer/navigation)
-- [ ] [P1] Header banner rendering from CMS-managed content
-- [ ] [P2] Basic SEO defaults (metadata, OG, sitemap, robots)
+- [x] [P1] Public app connected to shared data layer
+- [x] [P1] Localized route structure and middleware rules
+- [x] [P2] Public layout system (header/footer/navigation)
+- [x] [P1] Header banner rendering from CMS-managed content
+- [x] [P2] Basic SEO defaults (metadata, OG, sitemap, robots)
 
 ### Testing
 
@@ -204,6 +204,7 @@ This file is the single source of truth for roadmap and delivery progress.
 - [2026-02-10] E2E now runs with deterministic preparation (`test:e2e:prepare`: generate + migrate deploy + seed) before Playwright execution.
 - [2026-02-10] CI quality workflow `.gitea/workflows/ci.yml` enforces `check`, `typecheck`, `test`, and `test:e2e` against a PostgreSQL service.
 - [2026-02-10] Admin app now uses a shared shell with permission-aware navigation and dedicated IA routes (`/pages`, `/media`, `/users`, `/commissions`).
+- [2026-02-10] Public app now has a shared site layout (`banner/header/footer`), DB-backed header banner config, and SEO defaults (`metadata`, `robots`, `sitemap`).
 
 ## How We Use This File
 
diff --git a/apps/web/src/app/[locale]/about/page.tsx b/apps/web/src/app/[locale]/about/page.tsx
new file mode 100644
index 0000000..da3118f
--- /dev/null
+++ b/apps/web/src/app/[locale]/about/page.tsx
@@ -0,0 +1,13 @@
+import { getTranslations } from "next-intl/server"
+
+export default async function AboutPage() {
+  const t = await getTranslations("About")
+
+  return (
+    <section className="mx-auto w-full max-w-6xl space-y-4 px-6 py-16">
+      <p className="text-sm uppercase tracking-[0.2em] text-neutral-500">{t("badge")}</p>
+      <h1 className="text-4xl font-semibold tracking-tight">{t("title")}</h1>
+      <p className="max-w-3xl text-neutral-600">{t("description")}</p>
+    </section>
+  )
+}
diff --git a/apps/web/src/app/[locale]/contact/page.tsx b/apps/web/src/app/[locale]/contact/page.tsx
new file mode 100644
index 0000000..8970263
--- /dev/null
+++ b/apps/web/src/app/[locale]/contact/page.tsx
@@ -0,0 +1,13 @@
+import { getTranslations } from "next-intl/server"
+
+export default async function ContactPage() {
+  const t = await getTranslations("Contact")
+
+  return (
+    <section className="mx-auto w-full max-w-6xl space-y-4 px-6 py-16">
+      <p className="text-sm uppercase tracking-[0.2em] text-neutral-500">{t("badge")}</p>
+      <h1 className="text-4xl font-semibold tracking-tight">{t("title")}</h1>
+      <p className="max-w-3xl text-neutral-600">{t("description")}</p>
+    </section>
+  )
+}
diff --git a/apps/web/src/app/[locale]/layout.tsx b/apps/web/src/app/[locale]/layout.tsx
index d7bf5c4..7addb82 100644
--- a/apps/web/src/app/[locale]/layout.tsx
+++ b/apps/web/src/app/[locale]/layout.tsx
@@ -1,7 +1,12 @@
+import { getPublicHeaderBanner } from "@cms/db"
 import { notFound } from "next/navigation"
 import { hasLocale, NextIntlClientProvider } from "next-intl"
+import { getTranslations } from "next-intl/server"
 import type { ReactNode } from "react"
 
+import { PublicHeaderBanner } from "@/components/public-header-banner"
+import { PublicSiteFooter } from "@/components/public-site-footer"
+import { PublicSiteHeader } from "@/components/public-site-header"
 import { routing } from "@/i18n/routing"
 import { Providers } from "../providers"
 
@@ -12,6 +17,28 @@ type LocaleLayoutProps = {
   }>
 }
 
+export async function generateMetadata({ params }: LocaleLayoutProps) {
+  const { locale } = await params
+
+  if (!hasLocale(routing.locales, locale)) {
+    return {}
+  }
+
+  const t = await getTranslations({
+    locale,
+    namespace: "Seo",
+  })
+
+  return {
+    title: t("title"),
+    description: t("description"),
+    openGraph: {
+      title: t("title"),
+      description: t("description"),
+    },
+  }
+}
+
 export default async function LocaleLayout({ children, params }: LocaleLayoutProps) {
   const { locale } = await params
 
@@ -19,9 +46,16 @@ export default async function LocaleLayout({ children, params }: LocaleLayoutPro
     notFound()
   }
 
+  const banner = await getPublicHeaderBanner()
+
   return (
     <NextIntlClientProvider locale={locale}>
-      <Providers>{children}</Providers>
+      <Providers>
+        <PublicHeaderBanner banner={banner} />
+        <PublicSiteHeader />
+        <main>{children}</main>
+        <PublicSiteFooter />
+      </Providers>
     </NextIntlClientProvider>
   )
 }
diff --git a/apps/web/src/app/[locale]/page.tsx b/apps/web/src/app/[locale]/page.tsx
index ccc84c3..1b52219 100644
--- a/apps/web/src/app/[locale]/page.tsx
+++ b/apps/web/src/app/[locale]/page.tsx
@@ -2,20 +2,15 @@ import { listPosts } from "@cms/db"
 import { Button } from "@cms/ui/button"
 import { getTranslations } from "next-intl/server"
 
-import { LanguageSwitcher } from "@/components/language-switcher"
-
 export const dynamic = "force-dynamic"
 
 export default async function HomePage() {
   const [posts, t] = await Promise.all([listPosts(), getTranslations("Home")])
 
   return (
-    <main className="mx-auto flex min-h-screen w-full max-w-3xl flex-col gap-6 px-6 py-16">
+    <section className="mx-auto flex w-full max-w-6xl flex-col gap-6 px-6 py-16">
       <header className="space-y-3">
-        <div className="flex flex-wrap items-center justify-between gap-3">
-          <p className="text-sm uppercase tracking-[0.2em] text-neutral-500">{t("badge")}</p>
-          <LanguageSwitcher />
-        </div>
+        <p className="text-sm uppercase tracking-[0.2em] text-neutral-500">{t("badge")}</p>
         <h1 className="text-4xl font-semibold tracking-tight">{t("title")}</h1>
         <p className="text-neutral-600">{t("description")}</p>
       </header>
@@ -36,6 +31,6 @@ export default async function HomePage() {
           ))}
         </ul>
       </section>
-    </main>
+    </section>
   )
 }
diff --git a/apps/web/src/app/layout.tsx b/apps/web/src/app/layout.tsx
index b07fc12..f344f8a 100644
--- a/apps/web/src/app/layout.tsx
+++ b/apps/web/src/app/layout.tsx
@@ -3,9 +3,30 @@ import type { ReactNode } from "react"
 
 import "./globals.css"
 
+const metadataBase = new URL(process.env.CMS_WEB_ORIGIN ?? "http://localhost:3000")
+
 export const metadata: Metadata = {
-  title: "CMS Web",
+  metadataBase,
+  title: {
+    default: "CMS Web",
+    template: "%s | CMS Web",
+  },
   description: "Public frontend for the CMS monorepo",
+  applicationName: "CMS Web",
+  openGraph: {
+    type: "website",
+    siteName: "CMS Web",
+    title: "CMS Web",
+    description: "Public frontend for the CMS monorepo",
+    url: metadataBase,
+  },
+  alternates: {
+    canonical: "/",
+  },
+  robots: {
+    index: true,
+    follow: true,
+  },
 }
 
 export default function RootLayout({ children }: { children: ReactNode }) {
diff --git a/apps/web/src/app/robots.ts b/apps/web/src/app/robots.ts
new file mode 100644
index 0000000..77c45de
--- /dev/null
+++ b/apps/web/src/app/robots.ts
@@ -0,0 +1,13 @@
+import type { MetadataRoute } from "next"
+
+const baseUrl = process.env.CMS_WEB_ORIGIN ?? "http://localhost:3000"
+
+export default function robots(): MetadataRoute.Robots {
+  return {
+    rules: {
+      userAgent: "*",
+      allow: "/",
+    },
+    sitemap: `${baseUrl}/sitemap.xml`,
+  }
+}
diff --git a/apps/web/src/app/sitemap.ts b/apps/web/src/app/sitemap.ts
new file mode 100644
index 0000000..56de424
--- /dev/null
+++ b/apps/web/src/app/sitemap.ts
@@ -0,0 +1,14 @@
+import type { MetadataRoute } from "next"
+
+const baseUrl = process.env.CMS_WEB_ORIGIN ?? "http://localhost:3000"
+
+const publicRoutes = ["/", "/about", "/contact"]
+
+export default function sitemap(): MetadataRoute.Sitemap {
+  const now = new Date()
+
+  return publicRoutes.map((route) => ({
+    url: `${baseUrl}${route}`,
+    lastModified: now,
+  }))
+}
diff --git a/apps/web/src/components/public-header-banner.tsx b/apps/web/src/components/public-header-banner.tsx
new file mode 100644
index 0000000..23e9551
--- /dev/null
+++ b/apps/web/src/components/public-header-banner.tsx
@@ -0,0 +1,25 @@
+import type { PublicHeaderBanner as PublicHeaderBannerData } from "@cms/db"
+import Link from "next/link"
+
+type PublicHeaderBannerProps = {
+  banner: PublicHeaderBannerData | null
+}
+
+export function PublicHeaderBanner({ banner }: PublicHeaderBannerProps) {
+  if (!banner) {
+    return null
+  }
+
+  return (
+    <div className="border-b border-amber-200 bg-amber-50">
+      <div className="mx-auto flex w-full max-w-6xl flex-wrap items-center justify-between gap-3 px-6 py-2 text-sm text-amber-900">
+        <p>{banner.message}</p>
+        {banner.ctaLabel && banner.ctaHref ? (
+          <Link href={banner.ctaHref} className="font-medium underline underline-offset-2">
+            {banner.ctaLabel}
+          </Link>
+        ) : null}
+      </div>
+    </div>
+  )
+}
diff --git a/apps/web/src/components/public-site-footer.tsx b/apps/web/src/components/public-site-footer.tsx
new file mode 100644
index 0000000..aa3185d
--- /dev/null
+++ b/apps/web/src/components/public-site-footer.tsx
@@ -0,0 +1,21 @@
+"use client"
+
+import { useTranslations } from "next-intl"
+
+export function PublicSiteFooter() {
+  const t = useTranslations("Layout")
+  const year = new Date().getFullYear()
+
+  return (
+    <footer className="border-t border-neutral-200 bg-neutral-50">
+      <div className="mx-auto flex w-full max-w-6xl flex-wrap items-center justify-between gap-2 px-6 py-4 text-sm text-neutral-600">
+        <p>
+          {t("footer.copyright", {
+            year,
+          })}
+        </p>
+        <p>{t("footer.tagline")}</p>
+      </div>
+    </footer>
+  )
+}
diff --git a/apps/web/src/components/public-site-header.tsx b/apps/web/src/components/public-site-header.tsx
new file mode 100644
index 0000000..cf5703d
--- /dev/null
+++ b/apps/web/src/components/public-site-header.tsx
@@ -0,0 +1,44 @@
+"use client"
+
+import { useTranslations } from "next-intl"
+
+import { Link } from "@/i18n/navigation"
+
+import { LanguageSwitcher } from "./language-switcher"
+
+export function PublicSiteHeader() {
+  const t = useTranslations("Layout")
+
+  const navItems = [
+    { href: "/", label: t("nav.home") },
+    { href: "/about", label: t("nav.about") },
+    { href: "/contact", label: t("nav.contact") },
+  ]
+
+  return (
+    <header className="border-b border-neutral-200 bg-white/80 backdrop-blur">
+      <div className="mx-auto flex w-full max-w-6xl flex-wrap items-center justify-between gap-4 px-6 py-4">
+        <Link
+          href="/"
+          className="text-sm font-semibold uppercase tracking-[0.2em] text-neutral-700"
+        >
+          {t("brand")}
+        </Link>
+
+        <nav className="flex flex-wrap items-center gap-2">
+          {navItems.map((item) => (
+            <Link
+              key={item.href}
+              href={item.href}
+              className="rounded-md border border-neutral-300 px-3 py-1.5 text-sm font-medium text-neutral-700 hover:bg-neutral-100"
+            >
+              {item.label}
+            </Link>
+          ))}
+        </nav>
+
+        <LanguageSwitcher />
+      </div>
+    </header>
+  )
+}
diff --git a/apps/web/src/messages/de.json b/apps/web/src/messages/de.json
index f7d4473..f7e84e1 100644
--- a/apps/web/src/messages/de.json
+++ b/apps/web/src/messages/de.json
@@ -15,5 +15,31 @@
       "es": "Spanisch",
       "fr": "Französisch"
     }
+  },
+  "Layout": {
+    "brand": "CMS Web",
+    "nav": {
+      "home": "Start",
+      "about": "Über uns",
+      "contact": "Kontakt"
+    },
+    "footer": {
+      "copyright": "© {year} CMS Web",
+      "tagline": "Powered by Next.js, Bun, Prisma und TanStack."
+    }
+  },
+  "Seo": {
+    "title": "CMS Web",
+    "description": "Öffentliches Frontend für das CMS-Monorepo."
+  },
+  "About": {
+    "badge": "Über uns",
+    "title": "Über dieses Projekt",
+    "description": "Diese öffentliche App ist die Frontend-Oberfläche für CMS-gesteuerte Inhalte und kommende dynamische Seiten."
+  },
+  "Contact": {
+    "badge": "Kontakt",
+    "title": "Kontakt",
+    "description": "Kontakt- und Auftragsabläufe werden in den nächsten MVP-Schritten eingeführt."
   }
 }
diff --git a/apps/web/src/messages/en.json b/apps/web/src/messages/en.json
index 22b2dfc..3f3023a 100644
--- a/apps/web/src/messages/en.json
+++ b/apps/web/src/messages/en.json
@@ -15,5 +15,31 @@
       "es": "Spanish",
       "fr": "French"
     }
+  },
+  "Layout": {
+    "brand": "CMS Web",
+    "nav": {
+      "home": "Home",
+      "about": "About",
+      "contact": "Contact"
+    },
+    "footer": {
+      "copyright": "© {year} CMS Web",
+      "tagline": "Powered by Next.js, Bun, Prisma, and TanStack."
+    }
+  },
+  "Seo": {
+    "title": "CMS Web",
+    "description": "Public frontend for the CMS monorepo."
+  },
+  "About": {
+    "badge": "About",
+    "title": "About this project",
+    "description": "This public app is the frontend surface for CMS-driven content and upcoming dynamic pages."
+  },
+  "Contact": {
+    "badge": "Contact",
+    "title": "Contact",
+    "description": "Contact and commission flows will be introduced in upcoming MVP steps."
   }
 }
diff --git a/apps/web/src/messages/es.json b/apps/web/src/messages/es.json
index a157de6..64e49dd 100644
--- a/apps/web/src/messages/es.json
+++ b/apps/web/src/messages/es.json
@@ -15,5 +15,31 @@
       "es": "Español",
       "fr": "Francés"
     }
+  },
+  "Layout": {
+    "brand": "CMS Web",
+    "nav": {
+      "home": "Inicio",
+      "about": "Acerca de",
+      "contact": "Contacto"
+    },
+    "footer": {
+      "copyright": "© {year} CMS Web",
+      "tagline": "Impulsado por Next.js, Bun, Prisma y TanStack."
+    }
+  },
+  "Seo": {
+    "title": "CMS Web",
+    "description": "Frontend público para el monorepo CMS."
+  },
+  "About": {
+    "badge": "Acerca de",
+    "title": "Sobre este proyecto",
+    "description": "Esta app pública es la superficie frontend para contenido gestionado por CMS y próximas páginas dinámicas."
+  },
+  "Contact": {
+    "badge": "Contacto",
+    "title": "Contacto",
+    "description": "Los flujos de contacto y comisiones se incorporarán en los siguientes pasos del MVP."
   }
 }
diff --git a/apps/web/src/messages/fr.json b/apps/web/src/messages/fr.json
index 9817dee..f69a5b0 100644
--- a/apps/web/src/messages/fr.json
+++ b/apps/web/src/messages/fr.json
@@ -15,5 +15,31 @@
       "es": "Espagnol",
       "fr": "Français"
     }
+  },
+  "Layout": {
+    "brand": "CMS Web",
+    "nav": {
+      "home": "Accueil",
+      "about": "À propos",
+      "contact": "Contact"
+    },
+    "footer": {
+      "copyright": "© {year} CMS Web",
+      "tagline": "Propulsé par Next.js, Bun, Prisma et TanStack."
+    }
+  },
+  "Seo": {
+    "title": "CMS Web",
+    "description": "Frontend public pour le monorepo CMS."
+  },
+  "About": {
+    "badge": "À propos",
+    "title": "À propos de ce projet",
+    "description": "Cette application publique est la surface frontend pour le contenu piloté par CMS et les futures pages dynamiques."
+  },
+  "Contact": {
+    "badge": "Contact",
+    "title": "Contact",
+    "description": "Les flux de contact et de commission seront introduits dans les prochaines étapes MVP."
   }
 }
diff --git a/packages/db/prisma/seed.ts b/packages/db/prisma/seed.ts
index 3b947a1..5daa7ec 100644
--- a/packages/db/prisma/seed.ts
+++ b/packages/db/prisma/seed.ts
@@ -12,6 +12,20 @@ async function main() {
       status: "published",
     },
   })
+
+  await db.systemSetting.upsert({
+    where: { key: "public.header_banner" },
+    update: {},
+    create: {
+      key: "public.header_banner",
+      value: JSON.stringify({
+        enabled: true,
+        message: "New portfolio release is live.",
+        ctaLabel: "Open latest posts",
+        ctaHref: "/",
+      }),
+    },
+  })
 }
 
 main()
diff --git a/packages/db/src/index.ts b/packages/db/src/index.ts
index 4f14908..8cc6c44 100644
--- a/packages/db/src/index.ts
+++ b/packages/db/src/index.ts
@@ -7,4 +7,9 @@ export {
   registerPostCrudAuditHook,
   updatePost,
 } from "./posts"
-export { isAdminSelfRegistrationEnabled, setAdminSelfRegistrationEnabled } from "./settings"
+export type { PublicHeaderBanner } from "./settings"
+export {
+  getPublicHeaderBanner,
+  isAdminSelfRegistrationEnabled,
+  setAdminSelfRegistrationEnabled,
+} from "./settings"
diff --git a/packages/db/src/settings.ts b/packages/db/src/settings.ts
index fb3cd12..5d4ae33 100644
--- a/packages/db/src/settings.ts
+++ b/packages/db/src/settings.ts
@@ -1,6 +1,20 @@
 import { db } from "./client"
 
 const ADMIN_SELF_REGISTRATION_KEY = "admin.self_registration_enabled"
+const PUBLIC_HEADER_BANNER_KEY = "public.header_banner"
+
+type PublicHeaderBannerRecord = {
+  enabled: boolean
+  message: string
+  ctaLabel?: string
+  ctaHref?: string
+}
+
+export type PublicHeaderBanner = {
+  message: string
+  ctaLabel?: string
+  ctaHref?: string
+}
 
 function resolveEnvFallback(): boolean {
   return process.env.CMS_ADMIN_SELF_REGISTRATION_ENABLED === "true"
@@ -18,6 +32,25 @@ function parseStoredBoolean(value: string): boolean | null {
   return null
 }
 
+function parsePublicHeaderBanner(value: string): PublicHeaderBannerRecord | null {
+  try {
+    const parsed = JSON.parse(value) as Record<string, unknown>
+
+    if (typeof parsed.enabled !== "boolean" || typeof parsed.message !== "string") {
+      return null
+    }
+
+    return {
+      enabled: parsed.enabled,
+      message: parsed.message,
+      ctaLabel: typeof parsed.ctaLabel === "string" ? parsed.ctaLabel : undefined,
+      ctaHref: typeof parsed.ctaHref === "string" ? parsed.ctaHref : undefined,
+    }
+  } catch {
+    return null
+  }
+}
+
 export async function isAdminSelfRegistrationEnabled(): Promise<boolean> {
   try {
     const setting = await db.systemSetting.findUnique({
@@ -54,3 +87,30 @@ export async function setAdminSelfRegistrationEnabled(enabled: boolean): Promise
     },
   })
 }
+
+export async function getPublicHeaderBanner(): Promise<PublicHeaderBanner | null> {
+  try {
+    const setting = await db.systemSetting.findUnique({
+      where: { key: PUBLIC_HEADER_BANNER_KEY },
+      select: { value: true },
+    })
+
+    if (!setting) {
+      return null
+    }
+
+    const parsed = parsePublicHeaderBanner(setting.value)
+
+    if (!parsed || !parsed.enabled) {
+      return null
+    }
+
+    return {
+      message: parsed.message,
+      ctaLabel: parsed.ctaLabel,
+      ctaHref: parsed.ctaHref,
+    }
+  } catch {
+    return null
+  }
+}