diff --git a/web-next/app/[locale]/[...rest]/page.tsx b/web-next/app/[locale]/[...rest]/page.tsx
new file mode 100644
index 0000000..b8aff18
--- /dev/null
+++ b/web-next/app/[locale]/[...rest]/page.tsx
@@ -0,0 +1,9 @@
+import { notFound } from 'next/navigation'
+
+/**
+ * Catch-all de rutas inexistentes bajo un idioma: dispara notFound() para que
+ * se renderice la 404 temática (`[locale]/not-found.tsx`) dentro del layout.
+ */
+export default function CatchAllNotFound() {
+  notFound()
+}
diff --git a/web-next/app/[locale]/not-found.tsx b/web-next/app/[locale]/not-found.tsx
new file mode 100644
index 0000000..8916a1a
--- /dev/null
+++ b/web-next/app/[locale]/not-found.tsx
@@ -0,0 +1,26 @@
+import { getTranslations } from 'next-intl/server'
+
+/**
+ * 404 temática (dentro del layout de [locale] → cabecera/vídeo/pie + tema).
+ * Se muestra cuando se llama a notFound() dentro de un segmento de idioma,
+ * incluido el catch-all `[...rest]` para rutas inexistentes.
+ */
+export default async function NotFound() {
+  const t = await getTranslations('NotFound')
+  return (
+    <div className="main-page">
+      <div className="middle-content">
+        <div className="body-content">
+          <div className="title-content">
+            <h1>{t('title')}</h1>
+          </div>
+          <div className="box-content">
+            <div className="body-box-content justified">
+              <p>{t('message')}</p>
+            </div>
+          </div>
+        </div>
+      </div>
+    </div>
+  )
+}
diff --git a/web-next/messages/en.json b/web-next/messages/en.json
index 2deb289..bc3f9f7 100644
--- a/web-next/messages/en.json
+++ b/web-next/messages/en.json
@@ -510,5 +510,9 @@
     "backToStore": "Back to the store",
     "orderNotFound": "Order not found or already processed.",
     "genericError": "An error occurred. Please try again."
+  },
+  "NotFound": {
+    "title": "Page not found",
+    "message": "It looks like the page you are looking for doesn't exist or isn't available."
   }
 }
diff --git a/web-next/messages/es.json b/web-next/messages/es.json
index e302201..a4d5330 100644
--- a/web-next/messages/es.json
+++ b/web-next/messages/es.json
@@ -510,5 +510,9 @@
     "backToStore": "Volver a la tienda",
     "orderNotFound": "Orden no encontrada o ya procesada.",
     "genericError": "Ha ocurrido un error. Inténtalo de nuevo."
+  },
+  "NotFound": {
+    "title": "Página no encontrada",
+    "message": "Parece que la página que estás buscando no existe o no se encuentra disponible."
   }
 }