feat: add persistent responsive color themes

src/application/policies/color-scheme.js

@@ -0,0 +1,21 @@
+export const COLOR_SCHEME_PREFERENCES = Object.freeze([
+  "system",
+  "light",
+  "dark",
+]);
+
+/** @param {unknown} value */
+export function normalizeColorSchemePreference(value) {
+  return COLOR_SCHEME_PREFERENCES.includes(/** @type {string} */ (value))
+    ? /** @type {"system" | "light" | "dark"} */ (value)
+    : "system";
+}
+
+/**
+ * @param {"system" | "light" | "dark"} preference
+ * @param {boolean} systemPrefersDark
+ */
+export function resolveColorScheme(preference, systemPrefersDark) {
+  if (preference === "system") return systemPrefersDark ? "dark" : "light";
+  return preference;
+}

src/bootstrap/initialize-color-scheme.js

@@ -0,0 +1,36 @@
+import {
+  normalizeColorSchemePreference,
+  resolveColorScheme,
+} from "../application/policies/color-scheme.js";
+
+/**
+ * Applies the persisted public preference before React paints.
+ *
+ * @param {import("../application/ports/storage-port.js").StoragePort} storage
+ * @param {{
+ *   documentElement?: HTMLElement,
+ *   matchMedia?: (query: string) => MediaQueryList
+ * }} [browser]
+ */
+export function initializeColorScheme(storage, browser = {}) {
+  const documentElement = browser.documentElement ?? document.documentElement;
+  const matchMedia =
+    browser.matchMedia ??
+    (typeof window.matchMedia === "function"
+      ? window.matchMedia.bind(window)
+      : () => /** @type {MediaQueryList} */ ({ matches: false }));
+  const stored = storage.read("COLOR_SCHEME");
+  const preference = normalizeColorSchemePreference(
+    stored.ok ? stored.value : undefined,
+  );
+  const resolved = resolveColorScheme(
+    preference,
+    matchMedia("(prefers-color-scheme: dark)").matches,
+  );
+
+  documentElement.dataset.theme = resolved;
+  documentElement.dataset.themePreference = preference;
+  documentElement.style.colorScheme = resolved;
+
+  return Object.freeze({ preference, resolved });
+}

src/bootstrap/main.jsx

@@ -1,9 +1,11 @@
 import { StrictMode } from "react";
 import { createRoot } from "react-dom/client";
+import { QueryClientProvider } from "@tanstack/react-query";
 
 import { BootErrorShell } from "../presentation/boundaries/boot-error-shell.jsx";
 import { AppRouter } from "../presentation/routes/app-router.jsx";
 import { createRuntimeComposition } from "./create-runtime-composition.js";
+import { initializeColorScheme } from "./initialize-color-scheme.js";
 import { BootConfigError } from "./load-runtime-config.js";
 import { ReleaseManifestError } from "./load-release-manifest.js";
 import "../presentation/styles/theme.css";
@@ -19,12 +21,18 @@ const root = createRoot(rootElement);
 async function boot() {
   try {
     const composition = await createRuntimeComposition();
+    initializeColorScheme(composition.ports.storage);
     root.render(
       <StrictMode>
-        <AppRouter
-          authSession={composition.ports.authSession}
-          basename={composition.config.build.routerBasePath}
-        />
+        <QueryClientProvider client={composition.ports.queryClient}>
+          <AppRouter
+            authSession={composition.ports.authSession}
+            basename={composition.config.build.routerBasePath}
+            buildId={composition.release.buildId}
+            storage={composition.ports.storage}
+            telemetry={composition.ports.telemetry}
+          />
+        </QueryClientProvider>
       </StrictMode>,
     );
   } catch (error) {

src/contracts/routes.js

@@ -7,7 +7,10 @@
  *   access: "public" | "session-required" | "integration-defined",
  *   loadingSurface: string,
  *   errorSurface: string,
- *   chunkId: string
+ *   chunkId: string,
+ *   title: string,
+ *   navigationLabel: string | null,
+ *   navigationOrder: number | null
  * }} RouteDefinition
  */
 
@@ -24,6 +27,48 @@ export const ROUTE_REGISTRY = Object.freeze({
     loadingSurface: "app-shell",
     errorSurface: "route-boundary",
     chunkId: "route-home",
+    title: "시작",
+    navigationLabel: "시작",
+    navigationOrder: 10,
+  }),
+  EXAMPLES_UI: route({
+    routeId: "EXAMPLES_UI",
+    path: "/examples/ui",
+    paramsSchema: null,
+    searchSchema: null,
+    access: "public",
+    loadingSurface: "example-page",
+    errorSurface: "route-boundary",
+    chunkId: "route-examples-ui",
+    title: "UI 구성요소",
+    navigationLabel: "UI 구성요소",
+    navigationOrder: 20,
+  }),
+  EXAMPLES_STATES: route({
+    routeId: "EXAMPLES_STATES",
+    path: "/examples/states",
+    paramsSchema: null,
+    searchSchema: null,
+    access: "public",
+    loadingSurface: "example-page",
+    errorSurface: "route-boundary",
+    chunkId: "route-examples-states",
+    title: "화면 상태",
+    navigationLabel: "화면 상태",
+    navigationOrder: 30,
+  }),
+  EXAMPLES_AUTH: route({
+    routeId: "EXAMPLES_AUTH",
+    path: "/examples/auth",
+    paramsSchema: null,
+    searchSchema: null,
+    access: "public",
+    loadingSurface: "example-page",
+    errorSurface: "route-boundary",
+    chunkId: "route-examples-auth",
+    title: "인증 연동",
+    navigationLabel: "인증 연동",
+    navigationOrder: 40,
   }),
   SAMPLE_RESOURCE_LIST: route({
     routeId: "SAMPLE_RESOURCE_LIST",
@@ -34,6 +79,9 @@ export const ROUTE_REGISTRY = Object.freeze({
     loadingSurface: "sample-resource-list",
     errorSurface: "feature-boundary",
     chunkId: "route-sample-resources",
+    title: "보호된 연동 지점",
+    navigationLabel: "보호된 연동 지점",
+    navigationOrder: 50,
   }),
   NOT_FOUND: route({
     routeId: "NOT_FOUND",
@@ -44,9 +92,22 @@ export const ROUTE_REGISTRY = Object.freeze({
     loadingSurface: "none",
     errorSurface: "not-found",
     chunkId: "route-not-found",
+    title: "페이지를 찾을 수 없음",
+    navigationLabel: null,
+    navigationOrder: null,
   }),
 });
 
+export const NAVIGATION_ROUTES = Object.freeze(
+  Object.values(ROUTE_REGISTRY)
+    .filter((definition) => definition.navigationOrder !== null)
+    .sort(
+      (left, right) =>
+        /** @type {number} */ (left.navigationOrder) -
+        /** @type {number} */ (right.navigationOrder),
+    ),
+);
+
 /** @param {string} routeId */
 export function getRoute(routeId) {
   const registry = /** @type {Record<string, Readonly<RouteDefinition>>} */ (

src/presentation/components/async-surface.jsx

@@ -1,23 +1,40 @@
+import { useId } from "react";
+
+import { errorMessage } from "./error-copy.js";
+import { Button } from "./ui/button.jsx";
+
 /** @param {{ label?: string }} props */
 export function LoadingSurface({ label = "불러오는 중" }) {
   return (
     <section
+      className="state-surface state-surface--loading"
       aria-busy="true"
       aria-label={label}
       aria-live="polite"
       aria-atomic="true"
     >
       <div className="ui-skeleton" aria-hidden="true" />
-      <span className="sr-only">{label}</span>
+      <span className="visually-hidden">{label}</span>
     </section>
   );
 }
 
-/** @param {{ title?: string, action?: React.ReactNode }} props */
-export function EmptySurface({ title = "표시할 항목이 없습니다.", action }) {
+/**
+ * @param {{
+ *   title?: string,
+ *   description?: string,
+ *   action?: React.ReactNode
+ * }} props
+ */
+export function EmptySurface({
+  title = "표시할 항목이 없습니다.",
+  description,
+  action,
+}) {
   return (
-    <section className="ui-empty" aria-live="polite">
-      <p>{title}</p>
+    <section className="ui-empty state-surface" aria-live="polite">
+      <h2>{title}</h2>
+      {description ? <p>{description}</p> : null}
       {action}
     </section>
   );
@@ -32,17 +49,24 @@ export function EmptySurface({ title = "표시할 항목이 없습니다.", acti
  * }} props
  */
 export function TerminalErrorSurface({ userMessageKey, action, onAction }) {
+  const messageId = useId();
+  const actionLabels = Object.freeze({
+    retry: "다시 시도",
+    reauth: "로그인",
+    navigate: "안전한 화면으로 이동",
+    "reload-once": "한 번 새로고침",
+    "contact-support": "지원 정보 확인",
+  });
   return (
     <section
-      className="ui-terminal-error"
+      className="ui-terminal-error state-surface state-surface--danger"
       role="alert"
-      aria-labelledby="terminal-error-message"
+      aria-labelledby={messageId}
+      data-message-key={userMessageKey}
     >
-      <p id="terminal-error-message">{userMessageKey}</p>
+      <h2 id={messageId}>{errorMessage(userMessageKey)}</h2>
       {action !== "none" && (
-        <button className="ui-button" type="button" onClick={onAction}>
-          {action}
-        </button>
+        <Button onClick={onAction}>{actionLabels[action]}</Button>
       )}
     </section>
   );

src/presentation/components/error-copy.js

@@ -0,0 +1,21 @@
+const ERROR_MESSAGES = Object.freeze({
+  "error.network_unreachable": "네트워크에 연결할 수 없습니다.",
+  "error.request_timeout": "요청 시간이 초과되었습니다.",
+  "error.auth_required": "계속하려면 로그인이 필요합니다.",
+  "error.auth_integration_failure": "로그인 연동을 사용할 수 없습니다.",
+  "error.forbidden": "이 작업을 수행할 권한이 없습니다.",
+  "error.not_found": "요청한 항목을 찾을 수 없습니다.",
+  "error.rate_limited": "요청이 많습니다. 잠시 후 다시 시도해 주세요.",
+  "error.server_failure": "요청을 완료하지 못했습니다.",
+  "error.chunk_load_failure": "새 화면 파일을 불러오지 못했습니다.",
+  "error.render_failure": "화면을 표시하지 못했습니다.",
+  "error.unknown_failure": "예상하지 못한 문제가 발생했습니다.",
+});
+
+/** @param {string} messageKey */
+export function errorMessage(messageKey) {
+  const messages = /** @type {Readonly<Record<string, string>>} */ (
+    ERROR_MESSAGES
+  );
+  return messages[messageKey] ?? "요청을 완료하지 못했습니다.";
+}

src/presentation/components/page-header.jsx

@@ -0,0 +1,27 @@
+import { useEffect, useRef } from "react";
+
+/**
+ * @param {{
+ *   title: string,
+ *   description?: string,
+ *   eyebrow?: string
+ * }} props
+ */
+export function PageHeader({ title, description, eyebrow }) {
+  const headingRef = useRef(/** @type {HTMLHeadingElement | null} */ (null));
+
+  useEffect(() => {
+    document.title = `${title} · Frontend Skeleton`;
+    headingRef.current?.focus();
+  }, [title]);
+
+  return (
+    <header className="page-header">
+      {eyebrow ? <p className="page-header__eyebrow">{eyebrow}</p> : null}
+      <h1 ref={headingRef} tabIndex={-1} data-route-heading>
+        {title}
+      </h1>
+      {description ? <p className="page-header__description">{description}</p> : null}
+    </header>
+  );
+}

src/presentation/components/state-surfaces.jsx

@@ -0,0 +1,69 @@
+import { Button } from "./ui/button.jsx";
+
+/**
+ * @param {{
+ *   eyebrow: string,
+ *   title: string,
+ *   description: string,
+ *   actionLabel?: string,
+ *   onAction?: () => void,
+ *   tone?: "neutral" | "danger" | "warning"
+ * }} props
+ */
+function StateSurface({
+  eyebrow,
+  title,
+  description,
+  actionLabel,
+  onAction,
+  tone = "neutral",
+}) {
+  return (
+    <section className={`state-surface state-surface--${tone}`}>
+      <p className="state-surface__eyebrow">{eyebrow}</p>
+      <h2>{title}</h2>
+      <p>{description}</p>
+      {actionLabel ? <Button onClick={onAction}>{actionLabel}</Button> : null}
+    </section>
+  );
+}
+
+/** @param {{ onSignIn?: () => void }} props */
+export function AuthRequiredSurface({ onSignIn }) {
+  return (
+    <StateSurface
+      eyebrow="401 · 인증 필요"
+      title="로그인이 필요합니다."
+      description="세션을 시작한 뒤 이전 작업을 안전하게 계속할 수 있습니다."
+      actionLabel="로그인 시작"
+      onAction={onSignIn}
+    />
+  );
+}
+
+/** @param {{ onNavigate?: () => void }} props */
+export function ForbiddenSurface({ onNavigate }) {
+  return (
+    <StateSurface
+      eyebrow="403 · 권한 없음"
+      title="접근할 수 없습니다."
+      description="권한을 확인하거나 접근 가능한 화면으로 이동하세요."
+      actionLabel="안전한 화면으로 이동"
+      onAction={onNavigate}
+      tone="warning"
+    />
+  );
+}
+
+/** @param {{ onNavigate?: () => void }} props */
+export function NotFoundSurface({ onNavigate }) {
+  return (
+    <StateSurface
+      eyebrow="404 · 찾을 수 없음"
+      title="요청한 화면이 없습니다."
+      description="주소를 확인하거나 시작 화면으로 돌아가세요."
+      actionLabel="시작 화면으로 이동"
+      onAction={onNavigate}
+    />
+  );
+}

src/presentation/components/ui/alert.jsx

@@ -0,0 +1,36 @@
+/**
+ * @param {{
+ *   title: string,
+ *   children?: React.ReactNode,
+ *   variant?: "info" | "success" | "warning" | "danger",
+ *   onDismiss?: () => void
+ * }} props
+ */
+export function Alert({
+  title,
+  children,
+  variant = "info",
+  onDismiss,
+}) {
+  return (
+    <section
+      className={`ui-alert ui-alert--${variant}`}
+      role={variant === "danger" ? "alert" : "status"}
+    >
+      <div>
+        <strong>{title}</strong>
+        {children ? <div className="ui-alert__content">{children}</div> : null}
+      </div>
+      {onDismiss ? (
+        <button
+          className="ui-alert__dismiss"
+          type="button"
+          aria-label={`${title} 알림 닫기`}
+          onClick={onDismiss}
+        >
+          ×
+        </button>
+      ) : null}
+    </section>
+  );
+}

src/presentation/components/ui/badge.jsx

@@ -0,0 +1,9 @@
+/**
+ * @param {{
+ *   children: React.ReactNode,
+ *   variant?: "neutral" | "info" | "success" | "warning" | "danger"
+ * }} props
+ */
+export function Badge({ children, variant = "neutral" }) {
+  return <span className={`ui-badge ui-badge--${variant}`}>{children}</span>;
+}

src/presentation/components/ui/button.jsx

@@ -0,0 +1,24 @@
+/**
+ * @param {React.ButtonHTMLAttributes<HTMLButtonElement> & {
+ *   variant?: "primary" | "secondary" | "danger" | "ghost",
+ *   size?: "default" | "compact"
+ * }} props
+ */
+export function Button({
+  variant = "primary",
+  size = "default",
+  className = "",
+  type = "button",
+  ...props
+}) {
+  const classes = [
+    "ui-button",
+    `ui-button--${variant}`,
+    size === "compact" ? "ui-button--compact" : "",
+    className,
+  ]
+    .filter(Boolean)
+    .join(" ");
+
+  return <button {...props} className={classes} type={type} />;
+}

src/presentation/components/ui/card.jsx

@@ -0,0 +1,28 @@
+import { useId } from "react";
+
+/**
+ * @param {{
+ *   title: string,
+ *   description?: string,
+ *   children?: React.ReactNode,
+ *   footer?: React.ReactNode,
+ *   className?: string
+ * }} props
+ */
+export function Card({ title, description, children, footer, className = "" }) {
+  const titleId = useId();
+
+  return (
+    <article
+      className={`ui-card ${className}`.trim()}
+      aria-labelledby={titleId}
+    >
+      <div className="ui-card__header">
+        <h3 id={titleId}>{title}</h3>
+        {description ? <p>{description}</p> : null}
+      </div>
+      {children ? <div className="ui-card__content">{children}</div> : null}
+      {footer ? <footer className="ui-card__footer">{footer}</footer> : null}
+    </article>
+  );
+}

src/presentation/components/ui/dialog.jsx

@@ -0,0 +1,88 @@
+import { useEffect, useId, useRef } from "react";
+
+/**
+ * @param {{
+ *   open: boolean,
+ *   onClose: () => void,
+ *   title: string,
+ *   description?: string,
+ *   children?: React.ReactNode,
+ *   actions?: React.ReactNode
+ * }} props
+ */
+export function Dialog({
+  open,
+  onClose,
+  title,
+  description,
+  children,
+  actions,
+}) {
+  const dialogRef = useRef(/** @type {HTMLDialogElement | null} */ (null));
+  const previousFocusRef = useRef(/** @type {HTMLElement | null} */ (null));
+  const titleId = useId();
+  const descriptionId = useId();
+
+  useEffect(() => {
+    const dialog = dialogRef.current;
+    if (!dialog) return;
+
+    if (open) {
+      previousFocusRef.current =
+        document.activeElement instanceof HTMLElement
+          ? document.activeElement
+          : null;
+      if (!dialog.open) {
+        if (typeof dialog.showModal === "function") dialog.showModal();
+        else dialog.setAttribute("open", "");
+      }
+      const firstFocusable = dialog.querySelector(
+        "[autofocus], button, [href], input, select, textarea, [tabindex]:not([tabindex='-1'])",
+      );
+      if (firstFocusable instanceof HTMLElement) firstFocusable.focus();
+      return;
+    }
+
+    if (dialog.open) {
+      if (typeof dialog.close === "function") dialog.close();
+      else dialog.removeAttribute("open");
+    }
+    previousFocusRef.current?.focus();
+    previousFocusRef.current = null;
+  }, [open]);
+
+  return (
+    <dialog
+      className="ui-dialog"
+      ref={dialogRef}
+      aria-labelledby={titleId}
+      aria-describedby={description ? descriptionId : undefined}
+      onCancel={(event) => {
+        event.preventDefault();
+        onClose();
+      }}
+      onClick={(event) => {
+        if (event.target === event.currentTarget) onClose();
+      }}
+    >
+      <div className="ui-dialog__surface">
+        <header className="ui-dialog__header">
+          <div>
+            <h2 id={titleId}>{title}</h2>
+            {description ? <p id={descriptionId}>{description}</p> : null}
+          </div>
+          <button
+            className="ui-dialog__close"
+            type="button"
+            aria-label={`${title} 닫기`}
+            onClick={onClose}
+          >
+            ×
+          </button>
+        </header>
+        {children ? <div className="ui-dialog__content">{children}</div> : null}
+        {actions ? <footer className="ui-dialog__actions">{actions}</footer> : null}
+      </div>
+    </dialog>
+  );
+}

src/presentation/components/ui/text-field.jsx

@@ -0,0 +1,52 @@
+import { useId } from "react";
+
+/**
+ * @param {Omit<React.InputHTMLAttributes<HTMLInputElement>, "id"> & {
+ *   id?: string,
+ *   label: string,
+ *   description?: string,
+ *   error?: string
+ * }} props
+ */
+export function TextField({
+  id,
+  label,
+  description,
+  error,
+  className = "",
+  required,
+  ...inputProps
+}) {
+  const generatedId = useId();
+  const inputId = id ?? `field-${generatedId}`;
+  const descriptionId = description ? `${inputId}-description` : undefined;
+  const errorId = error ? `${inputId}-error` : undefined;
+  const describedBy = [descriptionId, errorId].filter(Boolean).join(" ");
+
+  return (
+    <div className={`ui-field ${className}`.trim()}>
+      <label className="ui-field__label" htmlFor={inputId}>
+        {label}
+        {required ? <span aria-hidden="true"> *</span> : null}
+      </label>
+      {description ? (
+        <p className="ui-field__description" id={descriptionId}>
+          {description}
+        </p>
+      ) : null}
+      <input
+        {...inputProps}
+        className="ui-field__input"
+        id={inputId}
+        required={required}
+        aria-describedby={describedBy || undefined}
+        aria-invalid={error ? "true" : undefined}
+      />
+      {error ? (
+        <p className="ui-field__error" id={errorId}>
+          {error}
+        </p>
+      ) : null}
+    </div>
+  );
+}

src/presentation/examples/auth-example-page.jsx

@@ -0,0 +1,80 @@
+import { useState } from "react";
+import { useLocation } from "react-router-dom";
+
+import { PageHeader } from "../components/page-header.jsx";
+import { useSession } from "../providers/session-provider.jsx";
+
+export default function AuthExamplePage() {
+  const location = useLocation();
+  const { sessionState, beginSignIn, signOut, recover } = useSession();
+  const [pending, setPending] = useState(false);
+  const [failed, setFailed] = useState(false);
+
+  /** @param {() => Promise<unknown>} action */
+  async function execute(action) {
+    setPending(true);
+    setFailed(false);
+    try {
+      await action();
+    } catch {
+      setFailed(true);
+    } finally {
+      setPending(false);
+    }
+  }
+
+  return (
+    <section className="ui-page">
+      <PageHeader
+        eyebrow="예제"
+        title="인증 연동"
+        description="스켈레톤은 자격 증명을 소유하지 않고 외부 인증 구현이 연결될 포트와 화면 상태만 제공합니다."
+      />
+      <section className="ui-panel auth-example" aria-labelledby="auth-state-title">
+        <div>
+          <h2 id="auth-state-title">현재 세션 상태</h2>
+          <output className="session-status" data-state={sessionState}>
+            {sessionState}
+          </output>
+        </div>
+        <div className="button-row">
+          <button
+            className="ui-button"
+            type="button"
+            disabled={pending || sessionState === "integration-failed"}
+            onClick={() =>
+              void execute(() =>
+                beginSignIn(`${location.pathname}${location.search}`),
+              )
+            }
+          >
+            로그인 시작
+          </button>
+          <button
+            className="ui-button ui-button--secondary"
+            type="button"
+            disabled={pending || sessionState !== "authenticated"}
+            onClick={() => void execute(signOut)}
+          >
+            로그아웃
+          </button>
+          <button
+            className="ui-button ui-button--secondary"
+            type="button"
+            disabled={pending || sessionState !== "recovery-pending"}
+            onClick={() => void execute(recover)}
+          >
+            세션 복구
+          </button>
+        </div>
+        {sessionState === "integration-failed" ? (
+          <p role="status">
+            외부 인증 소유자가 연결되지 않았습니다. 런타임 호스트의 인증
+            계약을 연결하세요.
+          </p>
+        ) : null}
+        {failed ? <p role="alert">인증 작업을 완료하지 못했습니다.</p> : null}
+      </section>
+    </section>
+  );
+}

src/presentation/examples/state-gallery-page.jsx

@@ -0,0 +1,98 @@
+import { useState } from "react";
+
+import { deriveAsyncState } from "../../application/view-models/async-state.js";
+import { createFailure } from "../../contracts/errors.js";
+import {
+  AsyncSurface,
+  EmptySurface,
+  LoadingSurface,
+  TerminalErrorSurface,
+} from "../components/async-surface.jsx";
+import { PageHeader } from "../components/page-header.jsx";
+import {
+  AuthRequiredSurface,
+  ForbiddenSurface,
+  NotFoundSurface,
+} from "../components/state-surfaces.jsx";
+import { Button } from "../components/ui/button.jsx";
+import { Card } from "../components/ui/card.jsx";
+
+export default function StateGalleryPage() {
+  const [lastAction, setLastAction] = useState(
+    "상태 화면의 작업을 선택하면 결과가 여기에 표시됩니다.",
+  );
+  const refreshingState = deriveAsyncState({
+    data: ["기존 데이터"],
+    isFetching: true,
+  });
+
+  return (
+    <section className="ui-page">
+      <PageHeader
+        eyebrow="예제"
+        title="화면 상태"
+        description="로딩, 빈 화면, 오류, 인증 필요와 권한 없음 상태가 다음 행동까지 일관되게 안내합니다."
+      />
+
+      <section className="gallery-section" aria-labelledby="async-states-title">
+        <header className="gallery-section__header">
+          <h2 id="async-states-title">비동기 데이터 상태</h2>
+          <p>초기 로딩과 백그라운드 갱신을 구분해 기존 콘텐츠를 보존합니다.</p>
+        </header>
+        <div className="component-grid component-grid--two">
+          <Card title="초기 로딩">
+            <LoadingSurface label="예제 데이터를 불러오는 중" />
+          </Card>
+          <Card title="백그라운드 갱신">
+            <AsyncSurface state={refreshingState}>
+              <div className="state-preview-content">기존 콘텐츠는 계속 표시됩니다.</div>
+            </AsyncSurface>
+          </Card>
+          <Card title="빈 화면">
+            <EmptySurface
+              title="아직 표시할 항목이 없습니다."
+              description="첫 항목을 추가하거나 필터를 초기화할 수 있습니다."
+              action={
+                <Button onClick={() => setLastAction("빈 화면 작업을 실행했습니다.")}>
+                  첫 작업 시작
+                </Button>
+              }
+            />
+          </Card>
+          <Card title="복구 가능한 오류">
+            <TerminalErrorSurface
+              userMessageKey={
+                createFailure("NETWORK_UNREACHABLE", "EXAMPLE", 0)
+                  .userMessageKey
+              }
+              action="retry"
+              onAction={() => setLastAction("오류 요청을 다시 시도했습니다.")}
+            />
+          </Card>
+        </div>
+      </section>
+
+      <section className="gallery-section" aria-labelledby="access-states-title">
+        <header className="gallery-section__header">
+          <h2 id="access-states-title">접근과 탐색 상태</h2>
+          <p>인증 여부와 서버 권한 결과를 서로 다른 상태로 전달합니다.</p>
+        </header>
+        <div className="component-grid component-grid--three">
+          <AuthRequiredSurface
+            onSignIn={() => setLastAction("로그인 연동 작업을 시작했습니다.")}
+          />
+          <ForbiddenSurface
+            onNavigate={() => setLastAction("접근 가능한 화면으로 이동합니다.")}
+          />
+          <NotFoundSurface
+            onNavigate={() => setLastAction("시작 화면으로 이동합니다.")}
+          />
+        </div>
+      </section>
+
+      <output className="gallery-notice" aria-live="polite">
+        {lastAction}
+      </output>
+    </section>
+  );
+}

src/presentation/examples/ui-gallery-page.jsx

@@ -0,0 +1,185 @@
+import { useState } from "react";
+
+import { PageHeader } from "../components/page-header.jsx";
+import { Alert } from "../components/ui/alert.jsx";
+import { Badge } from "../components/ui/badge.jsx";
+import { Button } from "../components/ui/button.jsx";
+import { Card } from "../components/ui/card.jsx";
+import { Dialog } from "../components/ui/dialog.jsx";
+import { TextField } from "../components/ui/text-field.jsx";
+
+const COLOR_TOKENS = Object.freeze([
+  ["Surface", "--color-surface"],
+  ["Muted surface", "--color-surface-muted"],
+  ["Content", "--color-content"],
+  ["Muted content", "--color-content-muted"],
+  ["Action", "--color-action"],
+  ["Danger", "--color-danger"],
+  ["Focus", "--color-focus"],
+]);
+
+export default function UiGalleryPage() {
+  const [projectName, setProjectName] = useState("");
+  const [fieldTouched, setFieldTouched] = useState(false);
+  const [dialogOpen, setDialogOpen] = useState(false);
+  const [notice, setNotice] = useState(
+    "구성요소를 조작하면 결과가 여기에 표시됩니다.",
+  );
+  const [alertVisible, setAlertVisible] = useState(true);
+  const fieldError =
+    fieldTouched && projectName.trim().length === 0
+      ? "프로젝트 이름을 입력해 주세요."
+      : undefined;
+
+  /** @param {React.FormEvent<HTMLFormElement>} event */
+  function submitExample(event) {
+    event.preventDefault();
+    setFieldTouched(true);
+    if (projectName.trim().length === 0) {
+      setNotice("입력값을 확인해 주세요.");
+      return;
+    }
+    setNotice(`“${projectName.trim()}” 입력을 확인했습니다.`);
+  }
+
+  return (
+    <section className="ui-page">
+      <PageHeader
+        eyebrow="예제"
+        title="UI 구성요소"
+        description="제품 도메인과 독립적인 공통 컨트롤, 피드백, 표면과 디자인 토큰을 직접 조작할 수 있습니다."
+      />
+
+      <section className="gallery-section" aria-labelledby="controls-title">
+        <header className="gallery-section__header">
+          <h2 id="controls-title">버튼과 입력</h2>
+          <p>키보드, 비활성 상태, 오류 설명을 포함한 기본 상호작용입니다.</p>
+        </header>
+        <div className="component-grid component-grid--two">
+          <Card title="버튼" description="의미와 위험도에 따라 변형을 선택합니다.">
+            <div className="button-row">
+              <Button onClick={() => setNotice("기본 작업을 실행했습니다.")}>
+                기본 작업
+              </Button>
+              <Button
+                variant="secondary"
+                onClick={() => setNotice("보조 작업을 실행했습니다.")}
+              >
+                보조 작업
+              </Button>
+              <Button
+                variant="danger"
+                onClick={() => setNotice("위험 작업 예제를 선택했습니다.")}
+              >
+                위험 작업
+              </Button>
+              <Button disabled>사용 불가</Button>
+            </div>
+          </Card>
+          <Card title="입력창" description="레이블과 도움말, 오류가 입력에 연결됩니다.">
+            <form className="example-form" noValidate onSubmit={submitExample}>
+              <TextField
+                label="프로젝트 이름"
+                description="새 도메인을 연결할 때 사용할 중립적인 예제입니다."
+                error={fieldError}
+                value={projectName}
+                required
+                onChange={(event) => setProjectName(event.currentTarget.value)}
+              />
+              <Button type="submit">입력 확인</Button>
+            </form>
+          </Card>
+        </div>
+      </section>
+
+      <section className="gallery-section" aria-labelledby="feedback-title">
+        <header className="gallery-section__header">
+          <h2 id="feedback-title">피드백과 모달</h2>
+          <p>상태 전달은 색에만 의존하지 않으며, 모든 제어에는 이름이 있습니다.</p>
+        </header>
+        <div className="component-grid component-grid--two">
+          <Card title="알림과 배지" description="짧은 상태와 문맥형 피드백입니다.">
+            <div className="component-stack">
+              {alertVisible ? (
+                <Alert
+                  title="설정이 저장되었습니다."
+                  variant="success"
+                  onDismiss={() => setAlertVisible(false)}
+                >
+                  <p>운영 환경에는 실제 저장 포트를 연결하세요.</p>
+                </Alert>
+              ) : (
+                <Button
+                  variant="secondary"
+                  onClick={() => setAlertVisible(true)}
+                >
+                  알림 다시 표시
+                </Button>
+              )}
+              <div className="badge-row" aria-label="배지 변형">
+                <Badge>중립</Badge>
+                <Badge variant="info">정보</Badge>
+                <Badge variant="success">준비됨</Badge>
+                <Badge variant="warning">확인 필요</Badge>
+                <Badge variant="danger">실패</Badge>
+              </div>
+            </div>
+          </Card>
+          <Card title="모달" description="배경과 키보드 Esc로 닫고 포커스를 복원합니다.">
+            <Button onClick={() => setDialogOpen(true)}>모달 열기</Button>
+            <Dialog
+              open={dialogOpen}
+              onClose={() => setDialogOpen(false)}
+              title="연동 확인"
+              description="도메인 작업을 실행하기 전 확인 화면의 기본 구조입니다."
+              actions={
+                <>
+                  <Button
+                    variant="secondary"
+                    onClick={() => setDialogOpen(false)}
+                  >
+                    취소
+                  </Button>
+                  <Button
+                    onClick={() => {
+                      setNotice("모달의 확인 작업을 실행했습니다.");
+                      setDialogOpen(false);
+                    }}
+                  >
+                    확인
+                  </Button>
+                </>
+              }
+            >
+              <p>민감한 값이나 구현 세부정보는 확인 문구에 포함하지 않습니다.</p>
+            </Dialog>
+          </Card>
+        </div>
+      </section>
+
+      <section className="gallery-section" aria-labelledby="tokens-title">
+        <header className="gallery-section__header">
+          <h2 id="tokens-title">디자인 토큰</h2>
+          <p>구성요소가 사용하는 의미 기반 색상과 형태 토큰입니다.</p>
+        </header>
+        <div className="token-grid">
+          {COLOR_TOKENS.map(([label, token]) => (
+            <article className="token-swatch" key={token}>
+              <span
+                className="token-swatch__color"
+                style={{ backgroundColor: `var(${token})` }}
+                aria-hidden="true"
+              />
+              <strong>{label}</strong>
+              <code>{token}</code>
+            </article>
+          ))}
+        </div>
+      </section>
+
+      <output className="gallery-notice" aria-live="polite">
+        {notice}
+      </output>
+    </section>
+  );
+}

src/presentation/layouts/app-shell.jsx

@@ -0,0 +1,160 @@
+import { useEffect, useState } from "react";
+import { NavLink, Outlet, useLocation } from "react-router-dom";
+
+import { NAVIGATION_ROUTES, routePath } from "../../contracts/routes.js";
+import { useSession } from "../providers/session-provider.jsx";
+import { useTheme } from "../providers/theme-provider.jsx";
+
+const SESSION_LABELS = Object.freeze({
+  authenticated: "인증됨",
+  unauthenticated: "로그인 전",
+  "recovery-pending": "복구 대기",
+  "integration-failed": "연동 필요",
+});
+
+export function AppShell() {
+  const location = useLocation();
+  const { sessionState, beginSignIn, signOut, recover } = useSession();
+  const { preference, setPreference } = useTheme();
+  const [navigationOpen, setNavigationOpen] = useState(false);
+  const [sessionActionPending, setSessionActionPending] = useState(false);
+  const [sessionActionFailed, setSessionActionFailed] = useState(false);
+
+  useEffect(() => {
+    setNavigationOpen(false);
+  }, [location.pathname]);
+
+  useEffect(() => {
+    if (!navigationOpen) return undefined;
+    /** @param {KeyboardEvent} event */
+    const closeOnEscape = (event) => {
+      if (event.key === "Escape") setNavigationOpen(false);
+    };
+    window.addEventListener("keydown", closeOnEscape);
+    return () => window.removeEventListener("keydown", closeOnEscape);
+  }, [navigationOpen]);
+
+  async function runSessionAction() {
+    setSessionActionPending(true);
+    setSessionActionFailed(false);
+    try {
+      if (sessionState === "authenticated") {
+        await signOut();
+      } else if (sessionState === "recovery-pending") {
+        await recover();
+      } else {
+        await beginSignIn(
+          `${location.pathname}${location.search}${location.hash}`,
+        );
+      }
+    } catch {
+      setSessionActionFailed(true);
+    } finally {
+      setSessionActionPending(false);
+    }
+  }
+
+  const sessionActionLabel =
+    sessionState === "authenticated"
+      ? "로그아웃"
+      : sessionState === "recovery-pending"
+        ? "세션 복구"
+        : "로그인";
+  const integrationAvailable = sessionState !== "integration-failed";
+
+  return (
+    <div className="app-shell">
+      <a className="skip-link" href="#main-content">
+        본문으로 건너뛰기
+      </a>
+      <header className="app-shell__header">
+        <button
+          className="app-shell__menu-button"
+          type="button"
+          aria-controls="primary-navigation"
+          aria-expanded={navigationOpen}
+          onClick={() => setNavigationOpen((open) => !open)}
+        >
+          <span aria-hidden="true">☰</span>
+          <span>메뉴</span>
+        </button>
+        <NavLink className="app-shell__brand" to={routePath("APP_HOME")}>
+          Frontend Skeleton
+        </NavLink>
+        <div className="app-shell__session">
+          <label className="visually-hidden" htmlFor="theme-preference">
+            색상 테마
+          </label>
+          <select
+            className="theme-selector"
+            id="theme-preference"
+            value={preference}
+            onChange={(event) =>
+              setPreference(
+                /** @type {"system" | "light" | "dark"} */ (
+                  event.currentTarget.value
+                ),
+              )
+            }
+          >
+            <option value="system">시스템 테마</option>
+            <option value="light">라이트 테마</option>
+            <option value="dark">다크 테마</option>
+          </select>
+          <span className="session-status" data-state={sessionState}>
+            {SESSION_LABELS[sessionState]}
+          </span>
+          {integrationAvailable ? (
+            <button
+              className="ui-button ui-button--compact"
+              type="button"
+              disabled={sessionActionPending}
+              onClick={() => void runSessionAction()}
+            >
+              {sessionActionPending ? "처리 중…" : sessionActionLabel}
+            </button>
+          ) : null}
+        </div>
+        {sessionActionFailed ? (
+          <p className="app-shell__session-error" role="alert">
+            세션 작업을 완료하지 못했습니다.
+          </p>
+        ) : null}
+      </header>
+      <aside
+        className="app-shell__sidebar"
+        data-open={navigationOpen}
+        aria-label="사이드바"
+      >
+        <nav id="primary-navigation" aria-label="주요 탐색">
+          <ul className="app-navigation">
+            {NAVIGATION_ROUTES.map((definition) => (
+              <li key={definition.routeId}>
+                <NavLink
+                  className={({ isActive }) =>
+                    `app-navigation__link${isActive ? " is-active" : ""}`
+                  }
+                  end={definition.path === "/"}
+                  to={definition.path}
+                >
+                  {definition.navigationLabel}
+                </NavLink>
+              </li>
+            ))}
+          </ul>
+        </nav>
+      </aside>
+      {navigationOpen ? (
+        <button
+          className="app-shell__scrim"
+          type="button"
+          aria-label="메뉴 닫기"
+          onClick={() => setNavigationOpen(false)}
+        />
+      ) : null}
+      <main className="app-shell__content" id="main-content" tabIndex={-1}>
+        <Outlet />
+      </main>
+    </div>
+  );
+}

src/presentation/pages/home-page.jsx

@@ -0,0 +1,56 @@
+import { Link } from "react-router-dom";
+
+import { routePath } from "../../contracts/routes.js";
+import { PageHeader } from "../components/page-header.jsx";
+
+const READINESS_ITEMS = Object.freeze([
+  {
+    title: "실행 계약",
+    description: "런타임 설정, 릴리스 정합성, 오류 경계가 마운트 전에 검증됩니다.",
+  },
+  {
+    title: "교체 가능한 연동",
+    description: "인증, HTTP, 캐시, 저장소, 텔레메트리가 포트 뒤에 분리되어 있습니다.",
+  },
+  {
+    title: "접근 가능한 화면",
+    description: "키보드 탐색, 포커스 이동, 반응형 앱 셸의 기본 동작이 준비되어 있습니다.",
+  },
+]);
+
+export default function HomePage() {
+  return (
+    <section className="ui-page">
+      <PageHeader
+        eyebrow="프로젝트 시작점"
+        title="Clean Architecture Frontend"
+        description="도메인을 추가하기 전에 실행 구조와 범용 사용자 경험을 확인할 수 있는 중립적인 스켈레톤입니다."
+      />
+      <div className="readiness-grid" aria-label="구현 준비 상태">
+        {READINESS_ITEMS.map((item) => (
+          <article className="ui-panel" key={item.title}>
+            <h2>{item.title}</h2>
+            <p>{item.description}</p>
+          </article>
+        ))}
+      </div>
+      <section className="ui-panel starter-actions" aria-labelledby="starter-title">
+        <div>
+          <h2 id="starter-title">준비된 화면 살펴보기</h2>
+          <p>공통 구성요소와 비동기 화면 상태를 예제 라우트에서 확인하세요.</p>
+        </div>
+        <div className="button-row">
+          <Link className="ui-button" to={routePath("EXAMPLES_UI")}>
+            UI 구성요소 보기
+          </Link>
+          <Link
+            className="ui-button ui-button--secondary"
+            to={routePath("EXAMPLES_STATES")}
+          >
+            화면 상태 보기
+          </Link>
+        </div>
+      </section>
+    </section>
+  );
+}

src/presentation/pages/not-found-page.jsx

@@ -0,0 +1,20 @@
+import { Link } from "react-router-dom";
+
+import { routePath } from "../../contracts/routes.js";
+import { PageHeader } from "../components/page-header.jsx";
+
+export default function NotFoundPage() {
+  return (
+    <section className="ui-page">
+      <PageHeader
+        title="페이지를 찾을 수 없습니다."
+        description="주소를 확인하거나 준비된 시작 화면으로 돌아가세요."
+      />
+      <div>
+        <Link className="ui-button" to={routePath("APP_HOME")}>
+          홈으로 이동
+        </Link>
+      </div>
+    </section>
+  );
+}

src/presentation/pages/sample-contract-page.jsx

@@ -0,0 +1,23 @@
+import { PageHeader } from "../components/page-header.jsx";
+import { useSession } from "../providers/session-provider.jsx";
+
+export default function SampleContractPage() {
+  const { sessionState } = useSession();
+
+  return (
+    <section className="ui-page">
+      <PageHeader
+        eyebrow="보호 라우트"
+        title="보호된 연동 지점"
+        description="실제 도메인 기능이 인증된 세션과 연결되는 위치를 보여주는 중립적인 계약 화면입니다."
+      />
+      <section className="ui-panel" aria-labelledby="protected-state-title">
+        <h2 id="protected-state-title">라우트 접근 허용</h2>
+        <p>
+          현재 세션 상태는 <strong>{sessionState}</strong>입니다. 서버의
+          권한 검증은 이 클라이언트 라우트 정책과 별도로 유지해야 합니다.
+        </p>
+      </section>
+    </section>
+  );
+}

src/presentation/providers/session-provider.jsx

@@ -0,0 +1,50 @@
+import { createContext, useContext, useMemo, useSyncExternalStore } from "react";
+
+/**
+ * @typedef {{
+ *   sessionState: import("../../application/ports/auth-session-port.js").SessionState,
+ *   beginSignIn: import("../../application/ports/auth-session-port.js").AuthSessionPort["beginSignIn"],
+ *   signOut: import("../../application/ports/auth-session-port.js").AuthSessionPort["signOut"],
+ *   recover: import("../../application/ports/auth-session-port.js").AuthSessionPort["recover"]
+ * }} SessionContextValue
+ */
+
+const SessionContext = createContext(
+  /** @type {SessionContextValue | null} */ (null),
+);
+
+/**
+ * @param {{
+ *   authSession: import("../../application/ports/auth-session-port.js").AuthSessionPort,
+ *   children: React.ReactNode
+ * }} props
+ */
+export function SessionProvider({ authSession, children }) {
+  const sessionState = useSyncExternalStore(
+    authSession.subscribe,
+    authSession.getState,
+    authSession.getState,
+  );
+  const value = useMemo(
+    () =>
+      Object.freeze({
+        sessionState,
+        beginSignIn: authSession.beginSignIn,
+        signOut: authSession.signOut,
+        recover: authSession.recover,
+      }),
+    [authSession, sessionState],
+  );
+
+  return (
+    <SessionContext.Provider value={value}>{children}</SessionContext.Provider>
+  );
+}
+
+export function useSession() {
+  const session = useContext(SessionContext);
+  if (!session) {
+    throw new Error("SessionProvider is required");
+  }
+  return session;
+}

src/presentation/providers/theme-provider.jsx

@@ -0,0 +1,86 @@
+import {
+  createContext,
+  useContext,
+  useEffect,
+  useLayoutEffect,
+  useMemo,
+  useState,
+} from "react";
+
+import {
+  normalizeColorSchemePreference,
+  resolveColorScheme,
+} from "../../application/policies/color-scheme.js";
+
+/**
+ * @typedef {{
+ *   preference: "system" | "light" | "dark",
+ *   resolvedTheme: "light" | "dark",
+ *   setPreference: (preference: "system" | "light" | "dark") => void
+ * }} ThemeContextValue
+ */
+
+const ThemeContext = createContext(/** @type {ThemeContextValue | null} */ (null));
+
+function systemPrefersDark() {
+  return (
+    typeof window.matchMedia === "function" &&
+    window.matchMedia("(prefers-color-scheme: dark)").matches
+  );
+}
+
+/**
+ * @param {{
+ *   storage?: import("../../application/ports/storage-port.js").StoragePort,
+ *   children: React.ReactNode
+ * }} props
+ */
+export function ThemeProvider({ storage, children }) {
+  const [preference, updatePreference] = useState(() => {
+    const result = storage?.read("COLOR_SCHEME");
+    return normalizeColorSchemePreference(
+      result?.ok ? result.value : undefined,
+    );
+  });
+  const [darkSystemTheme, setDarkSystemTheme] = useState(systemPrefersDark);
+  const resolvedTheme = resolveColorScheme(preference, darkSystemTheme);
+
+  useEffect(() => {
+    if (typeof window.matchMedia !== "function") return undefined;
+    const query = window.matchMedia("(prefers-color-scheme: dark)");
+    /** @param {MediaQueryListEvent} event */
+    const update = (event) => setDarkSystemTheme(event.matches);
+    setDarkSystemTheme(query.matches);
+    query.addEventListener("change", update);
+    return () => query.removeEventListener("change", update);
+  }, []);
+
+  useLayoutEffect(() => {
+    document.documentElement.dataset.theme = resolvedTheme;
+    document.documentElement.dataset.themePreference = preference;
+    document.documentElement.style.colorScheme = resolvedTheme;
+  }, [preference, resolvedTheme]);
+
+  const value = useMemo(
+    () =>
+      Object.freeze({
+        preference,
+        resolvedTheme,
+        /** @param {"system" | "light" | "dark"} next */
+        setPreference(next) {
+          const normalized = normalizeColorSchemePreference(next);
+          updatePreference(normalized);
+          storage?.write("COLOR_SCHEME", normalized);
+        },
+      }),
+    [preference, resolvedTheme, storage],
+  );
+
+  return <ThemeContext.Provider value={value}>{children}</ThemeContext.Provider>;
+}
+
+export function useTheme() {
+  const theme = useContext(ThemeContext);
+  if (!theme) throw new Error("ThemeProvider is required");
+  return theme;
+}

src/presentation/routes/app-router.jsx

@@ -1,81 +1,272 @@
+import { lazy, Suspense, useState } from "react";
 import {
   BrowserRouter,
-  Link,
   Route,
   Routes,
+  useLocation,
 } from "react-router-dom";
 
-import { routePath } from "../../contracts/routes.js";
+import { getRoute, routePath } from "../../contracts/routes.js";
+import { RouteBoundary } from "../boundaries/render-error-boundary.jsx";
+import { AppShell } from "../layouts/app-shell.jsx";
+import { PageHeader } from "../components/page-header.jsx";
+import { SessionProvider, useSession } from "../providers/session-provider.jsx";
+import { ThemeProvider } from "../providers/theme-provider.jsx";
 import { decideRouteAccess } from "./navigation-policy.js";
 
-function HomePage() {
+const HomePage = lazy(() => import("../pages/home-page.jsx"));
+const UiGalleryPage = lazy(() => import("../examples/ui-gallery-page.jsx"));
+const StateGalleryPage = lazy(
+  () => import("../examples/state-gallery-page.jsx"),
+);
+const AuthExamplePage = lazy(
+  () => import("../examples/auth-example-page.jsx"),
+);
+const SampleContractPage = lazy(
+  () => import("../pages/sample-contract-page.jsx"),
+);
+const NotFoundPage = lazy(() => import("../pages/not-found-page.jsx"));
+
+/** @param {{ routeId: string }} props */
+function RouteLoadingSurface({ routeId }) {
+  const definition = getRoute(routeId);
   return (
-    <main className="ui-page">
-      <h1>Clean Architecture Frontend</h1>
-      <p>런타임 계약이 검증되었습니다.</p>
-      <Link to={routePath("SAMPLE_RESOURCE_LIST")}>샘플 리소스</Link>
-    </main>
+    <section className="ui-page route-loading" aria-live="polite" aria-busy="true">
+      <div className="ui-skeleton" aria-hidden="true" />
+      <p>화면을 준비하고 있습니다.</p>
+      <span className="visually-hidden">{definition.title} 로딩 중</span>
+    </section>
   );
 }
 
-function SamplePlaceholder() {
+function RouteFailureSurface() {
   return (
-    <main className="ui-page">
-      <h1>샘플 리소스</h1>
-      <p>계약 fixture를 준비하고 있습니다.</p>
-    </main>
-  );
-}
-
-function NotFoundPage() {
-  return (
-    <main className="ui-page">
-      <h1>페이지를 찾을 수 없습니다.</h1>
-      <Link to={routePath("APP_HOME")}>홈으로 이동</Link>
-    </main>
+    <section className="ui-page">
+      <PageHeader
+        title="화면을 표시하지 못했습니다."
+        description="잠시 후 페이지를 새로고침해 주세요. 문제가 계속되면 운영 지원 참조 정보를 확인하세요."
+      />
+    </section>
   );
 }
 
 /**
  * @param {{
- *   authSession: import("../../application/ports/auth-session-port.js").AuthSessionPort
+ *   routeId: string,
+ *   buildId: string,
+ *   telemetry?: import("../../application/ports/telemetry-port.js").TelemetryPort,
+ *   children: React.ReactNode
  * }} props
  */
-function GuardedSampleRoute({ authSession }) {
-  const decision = decideRouteAccess(
-    "SAMPLE_RESOURCE_LIST",
-    authSession.getState(),
+function RouteSurface({ routeId, buildId, telemetry, children }) {
+  return (
+    <RouteBoundary
+      routeId={routeId}
+      buildId={buildId}
+      telemetry={telemetry}
+      fallback={<RouteFailureSurface />}
+    >
+      <Suspense fallback={<RouteLoadingSurface routeId={routeId} />}>
+        {children}
+      </Suspense>
+    </RouteBoundary>
   );
-  if (!decision.allowed) {
+}
+
+/**
+ * @param {{
+ *   routeId: string,
+ *   children: React.ReactNode
+ * }} props
+ */
+function ProtectedRoute({ routeId, children }) {
+  const location = useLocation();
+  const { sessionState, beginSignIn, recover } = useSession();
+  const [pending, setPending] = useState(false);
+  const [failed, setFailed] = useState(false);
+  const decision = decideRouteAccess(routeId, sessionState);
+
+  async function continueSession() {
+    setPending(true);
+    setFailed(false);
+    try {
+      if (decision.action === "wait-for-session") {
+        await recover();
+      } else {
+        await beginSignIn(
+          `${location.pathname}${location.search}${location.hash}`,
+        );
+      }
+    } catch {
+      setFailed(true);
+    } finally {
+      setPending(false);
+    }
+  }
+
+  if (decision.allowed) return children;
+
+  if (sessionState === "integration-failed") {
     return (
-      <main className="ui-page">
-        <h1>세션이 필요합니다.</h1>
-        <button className="ui-button" type="button">
-          로그인
-        </button>
-      </main>
+      <section className="ui-page">
+        <PageHeader
+          title="로그인 연동이 필요합니다."
+          description="외부 인증 소유자가 런타임에 연결되면 이 보호 라우트를 사용할 수 있습니다."
+        />
+      </section>
     );
   }
-  return <SamplePlaceholder />;
+
+  const recovering = decision.action === "wait-for-session";
+  return (
+    <section className="ui-page">
+      <PageHeader
+        title={recovering ? "세션을 복구하고 있습니다." : "세션이 필요합니다."}
+        description={
+          recovering
+            ? "기존 세션 확인을 계속하려면 복구를 실행하세요."
+            : "이 화면은 인증 연동 지점을 확인하기 위한 보호 라우트입니다."
+        }
+      />
+      <div>
+        <button
+          className="ui-button"
+          type="button"
+          disabled={pending}
+          onClick={() => void continueSession()}
+        >
+          {pending
+            ? "처리 중…"
+            : recovering
+              ? "세션 복구"
+              : "로그인 시작"}
+        </button>
+      </div>
+      {failed ? (
+        <p className="ui-terminal-error" role="alert">
+          세션 작업을 완료하지 못했습니다.
+        </p>
+      ) : null}
+    </section>
+  );
+}
+
+/**
+ * @param {{
+ *   routeId: string,
+ *   buildId: string,
+ *   telemetry?: import("../../application/ports/telemetry-port.js").TelemetryPort,
+ *   children: React.ReactNode
+ * }} props
+ */
+function PublicRoute({ routeId, buildId, telemetry, children }) {
+  return (
+    <RouteSurface routeId={routeId} buildId={buildId} telemetry={telemetry}>
+      {children}
+    </RouteSurface>
+  );
 }
 
 /**
  * @param {{
  *   authSession: import("../../application/ports/auth-session-port.js").AuthSessionPort,
- *   basename?: string
+ *   basename?: string,
+ *   buildId?: string,
+ *   storage?: import("../../application/ports/storage-port.js").StoragePort,
+ *   telemetry?: import("../../application/ports/telemetry-port.js").TelemetryPort
  * }} props
  */
-export function AppRouter({ authSession, basename = "/" }) {
+export function AppRouter({
+  authSession,
+  basename = "/",
+  buildId = "local-build",
+  storage,
+  telemetry,
+}) {
   return (
     <BrowserRouter basename={basename}>
-      <Routes>
-        <Route path={routePath("APP_HOME")} element={<HomePage />} />
-        <Route
-          path={routePath("SAMPLE_RESOURCE_LIST")}
-          element={<GuardedSampleRoute authSession={authSession} />}
-        />
-        <Route path={routePath("NOT_FOUND")} element={<NotFoundPage />} />
-      </Routes>
+      <ThemeProvider storage={storage}>
+        <SessionProvider authSession={authSession}>
+          <Routes>
+            <Route element={<AppShell />}>
+            <Route
+              index
+              element={
+                <PublicRoute
+                  routeId="APP_HOME"
+                  buildId={buildId}
+                  telemetry={telemetry}
+                >
+                  <HomePage />
+                </PublicRoute>
+              }
+            />
+            <Route
+              path={routePath("EXAMPLES_UI")}
+              element={
+                <PublicRoute
+                  routeId="EXAMPLES_UI"
+                  buildId={buildId}
+                  telemetry={telemetry}
+                >
+                  <UiGalleryPage />
+                </PublicRoute>
+              }
+            />
+            <Route
+              path={routePath("EXAMPLES_STATES")}
+              element={
+                <PublicRoute
+                  routeId="EXAMPLES_STATES"
+                  buildId={buildId}
+                  telemetry={telemetry}
+                >
+                  <StateGalleryPage />
+                </PublicRoute>
+              }
+            />
+            <Route
+              path={routePath("EXAMPLES_AUTH")}
+              element={
+                <PublicRoute
+                  routeId="EXAMPLES_AUTH"
+                  buildId={buildId}
+                  telemetry={telemetry}
+                >
+                  <AuthExamplePage />
+                </PublicRoute>
+              }
+            />
+            <Route
+              path={routePath("SAMPLE_RESOURCE_LIST")}
+              element={
+                <RouteSurface
+                  routeId="SAMPLE_RESOURCE_LIST"
+                  buildId={buildId}
+                  telemetry={telemetry}
+                >
+                  <ProtectedRoute routeId="SAMPLE_RESOURCE_LIST">
+                    <SampleContractPage />
+                  </ProtectedRoute>
+                </RouteSurface>
+              }
+            />
+            <Route
+              path={routePath("NOT_FOUND")}
+              element={
+                <PublicRoute
+                  routeId="NOT_FOUND"
+                  buildId={buildId}
+                  telemetry={telemetry}
+                >
+                  <NotFoundPage />
+                </PublicRoute>
+              }
+            />
+            </Route>
+          </Routes>
+        </SessionProvider>
+      </ThemeProvider>
     </BrowserRouter>
   );
 }

src/presentation/styles/theme.css

@@ -3,12 +3,28 @@
 @theme {
   --color-surface: oklch(0.985 0.003 247);
   --color-surface-muted: oklch(0.94 0.01 247);
+  --color-panel: oklch(1 0 0);
+  --color-border: oklch(0.87 0.015 247);
   --color-content: oklch(0.25 0.025 247);
   --color-content-muted: oklch(0.48 0.025 247);
   --color-action: oklch(0.55 0.18 255);
   --color-action-hover: oklch(0.48 0.2 255);
   --color-danger: oklch(0.55 0.2 25);
+  --color-danger-hover: oklch(0.47 0.2 25);
+  --color-on-action: oklch(1 0 0);
   --color-focus: oklch(0.72 0.16 225);
+  --color-info-content: oklch(0.38 0.16 255);
+  --color-info-surface: oklch(0.95 0.03 255);
+  --color-info-border: oklch(0.75 0.08 250);
+  --color-success-content: oklch(0.35 0.12 155);
+  --color-success-surface: oklch(0.95 0.04 155);
+  --color-success-border: oklch(0.72 0.1 155);
+  --color-warning-content: oklch(0.38 0.12 70);
+  --color-warning-surface: oklch(0.96 0.05 80);
+  --color-warning-border: oklch(0.75 0.12 80);
+  --color-danger-content: oklch(0.42 0.18 25);
+  --color-danger-surface: oklch(0.96 0.035 25);
+  --color-danger-border: oklch(0.72 0.12 25);
   --radius-control: 0.5rem;
   --radius-surface: 0.75rem;
   --spacing-page: 1.5rem;
@@ -22,8 +38,64 @@
     font-family: var(--font-sans);
   }
 
+  :root[data-theme="dark"] {
+    --color-surface: oklch(0.16 0.02 255);
+    --color-surface-muted: oklch(0.25 0.025 255);
+    --color-panel: oklch(0.205 0.022 255);
+    --color-border: oklch(0.36 0.025 255);
+    --color-content: oklch(0.94 0.012 255);
+    --color-content-muted: oklch(0.74 0.025 255);
+    --color-action: oklch(0.7 0.14 250);
+    --color-action-hover: oklch(0.79 0.12 245);
+    --color-danger: oklch(0.68 0.19 25);
+    --color-danger-hover: oklch(0.76 0.16 25);
+    --color-on-action: oklch(0.16 0.02 255);
+    --color-focus: oklch(0.82 0.15 220);
+    --color-info-content: oklch(0.83 0.09 250);
+    --color-info-surface: oklch(0.27 0.045 255);
+    --color-info-border: oklch(0.55 0.09 250);
+    --color-success-content: oklch(0.83 0.1 155);
+    --color-success-surface: oklch(0.27 0.045 155);
+    --color-success-border: oklch(0.53 0.1 155);
+    --color-warning-content: oklch(0.88 0.1 80);
+    --color-warning-surface: oklch(0.29 0.045 80);
+    --color-warning-border: oklch(0.58 0.11 80);
+    --color-danger-content: oklch(0.84 0.11 25);
+    --color-danger-surface: oklch(0.28 0.055 25);
+    --color-danger-border: oklch(0.56 0.13 25);
+  }
+
   body {
     margin: 0;
+    min-width: 20rem;
+    min-height: 100vh;
+  }
+
+  button,
+  input,
+  textarea,
+  select {
+    font: inherit;
+  }
+
+  a {
+    color: inherit;
+  }
+
+  h1,
+  h2,
+  p {
+    margin-block-start: 0;
+  }
+
+  h1 {
+    font-size: clamp(2rem, 5vw, 3.5rem);
+    line-height: 1.05;
+    letter-spacing: -0.04em;
+  }
+
+  h2 {
+    line-height: 1.25;
   }
 
   :focus-visible {
@@ -33,22 +105,245 @@
 }
 
 @layer components {
+  .visually-hidden {
+    position: absolute;
+    width: 1px;
+    height: 1px;
+    padding: 0;
+    margin: -1px;
+    overflow: hidden;
+    clip: rect(0, 0, 0, 0);
+    white-space: nowrap;
+    border: 0;
+  }
+
+  .skip-link {
+    position: fixed;
+    z-index: 100;
+    top: 0.75rem;
+    left: 0.75rem;
+    padding: 0.75rem 1rem;
+    border-radius: var(--radius-control);
+    color: var(--color-panel);
+    background: var(--color-content);
+    transform: translateY(-200%);
+  }
+
+  .skip-link:focus {
+    transform: translateY(0);
+  }
+
+  .app-shell {
+    display: grid;
+    min-height: 100vh;
+    grid-template-rows: 4.5rem 1fr;
+    grid-template-columns: 15rem minmax(0, 1fr);
+    grid-template-areas:
+      "header header"
+      "sidebar content";
+  }
+
+  .app-shell__header {
+    position: sticky;
+    z-index: 30;
+    top: 0;
+    grid-area: header;
+    display: flex;
+    align-items: center;
+    gap: 1rem;
+    min-width: 0;
+    padding: 0.75rem 1.25rem;
+    border-bottom: 1px solid var(--color-surface-muted);
+    background: color-mix(in oklch, var(--color-panel) 92%, var(--color-surface));
+    box-shadow: 0 1px 8px color-mix(in oklch, var(--color-content) 8%, transparent);
+  }
+
+  .app-shell__brand {
+    overflow: hidden;
+    font-size: 1.05rem;
+    font-weight: 800;
+    text-decoration: none;
+    text-overflow: ellipsis;
+    white-space: nowrap;
+  }
+
+  .app-shell__menu-button {
+    display: none;
+    align-items: center;
+    gap: 0.4rem;
+    border: 1px solid var(--color-surface-muted);
+    border-radius: var(--radius-control);
+    padding: 0.55rem 0.75rem;
+    color: var(--color-content);
+    background: var(--color-panel);
+    cursor: pointer;
+  }
+
+  .app-shell__session {
+    display: flex;
+    align-items: center;
+    gap: 0.75rem;
+    margin-inline-start: auto;
+  }
+
+  .theme-selector {
+    min-height: 2.25rem;
+    max-width: 8.5rem;
+    border: 1px solid var(--color-border);
+    border-radius: var(--radius-control);
+    padding: 0.35rem 2rem 0.35rem 0.65rem;
+    color: var(--color-content);
+    background: var(--color-panel);
+    cursor: pointer;
+  }
+
+  .app-shell__session-error {
+    position: absolute;
+    top: calc(100% + 0.25rem);
+    right: 1rem;
+    padding: 0.5rem;
+    color: var(--color-danger);
+    background: var(--color-panel);
+  }
+
+  .session-status {
+    display: inline-flex;
+    width: fit-content;
+    align-items: center;
+    border-radius: 999px;
+    padding: 0.3rem 0.65rem;
+    color: var(--color-content-muted);
+    background: var(--color-surface-muted);
+    font-size: 0.8rem;
+    font-weight: 700;
+  }
+
+  .session-status[data-state="authenticated"] {
+    color: var(--color-success-content);
+    background: var(--color-success-surface);
+  }
+
+  .session-status[data-state="integration-failed"] {
+    color: var(--color-danger);
+  }
+
+  .app-shell__sidebar {
+    position: sticky;
+    top: 4.5rem;
+    grid-area: sidebar;
+    height: calc(100vh - 4.5rem);
+    padding: 1.25rem 0.75rem;
+    border-right: 1px solid var(--color-border);
+    background: var(--color-panel);
+  }
+
+  .app-navigation {
+    display: flex;
+    flex-direction: column;
+    gap: 0.25rem;
+    margin: 0;
+    padding: 0;
+    list-style: none;
+  }
+
+  .app-navigation__link {
+    display: block;
+    border-radius: var(--radius-control);
+    padding: 0.75rem 0.9rem;
+    color: var(--color-content-muted);
+    font-weight: 650;
+    text-decoration: none;
+  }
+
+  .app-navigation__link:hover {
+    color: var(--color-content);
+    background: var(--color-surface);
+  }
+
+  .app-navigation__link.is-active {
+    color: var(--color-action-hover);
+    background: color-mix(
+      in oklch,
+      var(--color-action) 14%,
+      var(--color-panel)
+    );
+    font-weight: 800;
+  }
+
+  .app-shell__content {
+    grid-area: content;
+    min-width: 0;
+  }
+
   .ui-page {
-    @apply mx-auto flex min-h-screen max-w-4xl flex-col gap-6 p-page;
+    @apply mx-auto flex max-w-6xl flex-col gap-6 p-page;
+    width: 100%;
+    box-sizing: border-box;
   }
 
   .ui-panel {
-    @apply rounded-surface border border-surface-muted bg-white p-6 shadow-sm;
+    @apply rounded-surface p-6 shadow-sm;
+    border: 1px solid var(--color-border);
+    background: var(--color-panel);
   }
 
   .ui-button {
-    @apply rounded-control bg-action px-4 py-2 font-semibold text-white;
+    @apply rounded-control bg-action px-4 py-2 font-semibold;
+    display: inline-flex;
+    min-height: 2.75rem;
+    align-items: center;
+    justify-content: center;
+    border: 0;
+    color: var(--color-on-action);
+    text-decoration: none;
+    cursor: pointer;
   }
 
   .ui-button:hover {
     @apply bg-action-hover;
   }
 
+  .ui-button:disabled {
+    cursor: not-allowed;
+    opacity: 0.55;
+  }
+
+  .ui-button--secondary {
+    border: 1px solid var(--color-surface-muted);
+    color: var(--color-content);
+    background: var(--color-panel);
+  }
+
+  .ui-button--secondary:hover {
+    color: var(--color-action);
+    background: var(--color-surface);
+  }
+
+  .ui-button--danger {
+    color: var(--color-on-action);
+    background: var(--color-danger);
+  }
+
+  .ui-button--danger:hover {
+    background: var(--color-danger-hover);
+  }
+
+  .ui-button--ghost {
+    color: var(--color-content);
+    background: transparent;
+  }
+
+  .ui-button--ghost:hover {
+    color: var(--color-action);
+    background: var(--color-surface-muted);
+  }
+
+  .ui-button--compact {
+    min-height: 2.25rem;
+    padding: 0.4rem 0.75rem;
+    font-size: 0.85rem;
+  }
+
   .ui-skeleton {
     @apply h-24 animate-pulse rounded-surface bg-surface-muted;
   }
@@ -57,6 +352,486 @@
   .ui-terminal-error {
     @apply rounded-surface border border-surface-muted p-6;
   }
+
+  .ui-field {
+    display: grid;
+    gap: 0.45rem;
+  }
+
+  .ui-field__label {
+    font-weight: 750;
+  }
+
+  .ui-field__description,
+  .ui-field__error {
+    margin: 0;
+    font-size: 0.875rem;
+    line-height: 1.5;
+  }
+
+  .ui-field__description {
+    color: var(--color-content-muted);
+  }
+
+  .ui-field__error {
+    color: var(--color-danger);
+    font-weight: 650;
+  }
+
+  .ui-field__input {
+    width: 100%;
+    min-height: 2.75rem;
+    box-sizing: border-box;
+    border: 1px solid
+      color-mix(in oklch, var(--color-content-muted) 55%, var(--color-panel));
+    border-radius: var(--radius-control);
+    padding: 0.65rem 0.8rem;
+    color: var(--color-content);
+    background: var(--color-panel);
+  }
+
+  .ui-field__input[aria-invalid="true"] {
+    border-color: var(--color-danger);
+  }
+
+  .ui-card {
+    display: flex;
+    min-width: 0;
+    flex-direction: column;
+    gap: 1.25rem;
+    border: 1px solid var(--color-border);
+    border-radius: var(--radius-surface);
+    padding: 1.25rem;
+    background: var(--color-panel);
+    box-shadow: 0 8px 28px color-mix(in oklch, var(--color-content) 6%, transparent);
+  }
+
+  .ui-card__header h3,
+  .ui-card__header p {
+    margin-block-end: 0;
+  }
+
+  .ui-card__header p {
+    margin-block-start: 0.4rem;
+    color: var(--color-content-muted);
+    line-height: 1.55;
+  }
+
+  .ui-card__content {
+    flex: 1;
+  }
+
+  .ui-card__footer {
+    padding-block-start: 1rem;
+    border-top: 1px solid var(--color-surface-muted);
+  }
+
+  .ui-alert {
+    display: flex;
+    align-items: flex-start;
+    justify-content: space-between;
+    gap: 1rem;
+    border: 1px solid var(--color-surface-muted);
+    border-radius: var(--radius-control);
+    padding: 1rem;
+    background: var(--color-surface);
+  }
+
+  .ui-alert--info {
+    border-color: var(--color-info-border);
+    background: var(--color-info-surface);
+  }
+
+  .ui-alert--success {
+    border-color: var(--color-success-border);
+    background: var(--color-success-surface);
+  }
+
+  .ui-alert--warning {
+    border-color: var(--color-warning-border);
+    background: var(--color-warning-surface);
+  }
+
+  .ui-alert--danger {
+    border-color: var(--color-danger-border);
+    background: var(--color-danger-surface);
+  }
+
+  .ui-alert__content,
+  .ui-alert__content p {
+    margin-block: 0.35rem 0;
+    color: var(--color-content-muted);
+  }
+
+  .ui-alert__dismiss,
+  .ui-dialog__close {
+    display: inline-grid;
+    width: 2rem;
+    height: 2rem;
+    flex: 0 0 auto;
+    place-items: center;
+    border: 0;
+    border-radius: var(--radius-control);
+    color: var(--color-content);
+    background: transparent;
+    font-size: 1.35rem;
+    cursor: pointer;
+  }
+
+  .ui-alert__dismiss:hover,
+  .ui-dialog__close:hover {
+    background: color-mix(in oklch, var(--color-content) 8%, transparent);
+  }
+
+  .ui-badge {
+    display: inline-flex;
+    border-radius: 999px;
+    padding: 0.3rem 0.65rem;
+    color: var(--color-content);
+    background: var(--color-surface-muted);
+    font-size: 0.8rem;
+    font-weight: 750;
+  }
+
+  .ui-badge--info {
+    color: var(--color-info-content);
+    background: var(--color-info-surface);
+  }
+
+  .ui-badge--success {
+    color: var(--color-success-content);
+    background: var(--color-success-surface);
+  }
+
+  .ui-badge--warning {
+    color: var(--color-warning-content);
+    background: var(--color-warning-surface);
+  }
+
+  .ui-badge--danger {
+    color: var(--color-danger-content);
+    background: var(--color-danger-surface);
+  }
+
+  .ui-dialog {
+    width: min(34rem, calc(100vw - 2rem));
+    max-height: calc(100vh - 2rem);
+    box-sizing: border-box;
+    overflow: auto;
+    border: 0;
+    border-radius: var(--radius-surface);
+    padding: 0;
+    color: var(--color-content);
+    background: var(--color-panel);
+    box-shadow: 0 24px 70px color-mix(in oklch, var(--color-content) 25%, transparent);
+  }
+
+  .ui-dialog::backdrop {
+    background: color-mix(in oklch, var(--color-content) 55%, transparent);
+    backdrop-filter: blur(2px);
+  }
+
+  .ui-dialog__surface {
+    padding: 1.5rem;
+  }
+
+  .ui-dialog__header {
+    display: flex;
+    align-items: flex-start;
+    justify-content: space-between;
+    gap: 1rem;
+  }
+
+  .ui-dialog__header h2 {
+    margin-block-end: 0.35rem;
+  }
+
+  .ui-dialog__header p,
+  .ui-dialog__content p {
+    color: var(--color-content-muted);
+    line-height: 1.6;
+  }
+
+  .ui-dialog__content {
+    padding-block: 1rem;
+  }
+
+  .ui-dialog__actions {
+    display: flex;
+    flex-wrap: wrap;
+    justify-content: flex-end;
+    gap: 0.75rem;
+    padding-block-start: 1rem;
+    border-top: 1px solid var(--color-surface-muted);
+  }
+
+  .page-header {
+    max-width: 50rem;
+    padding-block: clamp(1rem, 5vw, 3.5rem) 0.5rem;
+  }
+
+  [data-route-heading]:focus {
+    outline: none;
+  }
+
+  .page-header__eyebrow {
+    margin-block-end: 0.75rem;
+    color: var(--color-action);
+    font-size: 0.8rem;
+    font-weight: 800;
+    letter-spacing: 0.08em;
+    text-transform: uppercase;
+  }
+
+  .page-header__description {
+    max-width: 45rem;
+    color: var(--color-content-muted);
+    font-size: 1.05rem;
+    line-height: 1.7;
+  }
+
+  .readiness-grid {
+    display: grid;
+    grid-template-columns: repeat(3, minmax(0, 1fr));
+    gap: 1rem;
+  }
+
+  .readiness-grid p,
+  .starter-actions p {
+    margin-block-end: 0;
+    color: var(--color-content-muted);
+    line-height: 1.65;
+  }
+
+  .starter-actions,
+  .auth-example {
+    display: flex;
+    flex-wrap: wrap;
+    align-items: center;
+    justify-content: space-between;
+    gap: 1.5rem;
+  }
+
+  .button-row {
+    display: flex;
+    flex-wrap: wrap;
+    gap: 0.75rem;
+  }
+
+  .route-loading {
+    padding-block-start: 4rem;
+  }
+
+  .gallery-section {
+    display: grid;
+    gap: 1rem;
+    padding-block: 0.5rem;
+  }
+
+  .gallery-section__header {
+    max-width: 45rem;
+  }
+
+  .gallery-section__header h2,
+  .gallery-section__header p {
+    margin-block-end: 0;
+  }
+
+  .gallery-section__header p {
+    margin-block-start: 0.4rem;
+    color: var(--color-content-muted);
+    line-height: 1.6;
+  }
+
+  .component-grid {
+    display: grid;
+    gap: 1rem;
+  }
+
+  .component-grid--two {
+    grid-template-columns: repeat(2, minmax(0, 1fr));
+  }
+
+  .component-grid--three {
+    grid-template-columns: repeat(3, minmax(0, 1fr));
+  }
+
+  .component-stack,
+  .example-form {
+    display: grid;
+    gap: 1rem;
+  }
+
+  .badge-row {
+    display: flex;
+    flex-wrap: wrap;
+    gap: 0.5rem;
+  }
+
+  .token-grid {
+    display: grid;
+    grid-template-columns: repeat(auto-fit, minmax(10rem, 1fr));
+    gap: 0.75rem;
+  }
+
+  .token-swatch {
+    display: grid;
+    gap: 0.45rem;
+    min-width: 0;
+    border: 1px solid var(--color-border);
+    border-radius: var(--radius-control);
+    padding: 0.75rem;
+    background: var(--color-panel);
+  }
+
+  .token-swatch__color {
+    height: 4rem;
+    border: 1px solid color-mix(in oklch, var(--color-content) 15%, transparent);
+    border-radius: calc(var(--radius-control) / 1.5);
+  }
+
+  .token-swatch code {
+    overflow: hidden;
+    color: var(--color-content-muted);
+    font-size: 0.75rem;
+    text-overflow: ellipsis;
+    white-space: nowrap;
+  }
+
+  .gallery-notice {
+    display: block;
+    width: fit-content;
+    max-width: 100%;
+    box-sizing: border-box;
+    border: 1px solid var(--color-surface-muted);
+    border-radius: 999px;
+    padding: 0.65rem 1rem;
+    color: var(--color-content);
+    background: var(--color-panel);
+    box-shadow: 0 8px 28px color-mix(in oklch, var(--color-content) 10%, transparent);
+    font-size: 0.875rem;
+    font-weight: 650;
+  }
+
+  .state-surface {
+    display: flex;
+    min-height: 12rem;
+    box-sizing: border-box;
+    flex-direction: column;
+    align-items: flex-start;
+    justify-content: center;
+    border: 1px solid var(--color-surface-muted);
+    border-radius: var(--radius-surface);
+    padding: 1.25rem;
+    background: var(--color-surface);
+  }
+
+  .state-surface h2,
+  .state-surface p {
+    margin-block-end: 0.75rem;
+  }
+
+  .state-surface > p:not(.state-surface__eyebrow) {
+    color: var(--color-content-muted);
+    line-height: 1.55;
+  }
+
+  .state-surface__eyebrow {
+    color: var(--color-action-hover);
+    font-size: 0.75rem;
+    font-weight: 800;
+    letter-spacing: 0.04em;
+  }
+
+  .state-surface--warning {
+    border-color: var(--color-warning-border);
+    background: var(--color-warning-surface);
+  }
+
+  .state-surface--danger,
+  .ui-terminal-error {
+    border-color: var(--color-danger-border);
+    background: var(--color-danger-surface);
+  }
+
+  .state-surface--loading {
+    gap: 0.75rem;
+  }
+
+  .state-surface--loading .ui-skeleton {
+    width: 100%;
+  }
+
+  .state-preview-content {
+    border-radius: var(--radius-control);
+    padding: 1rem;
+    background: var(--color-surface);
+  }
+
+  .app-shell__scrim {
+    display: none;
+  }
+}
+
+@media (max-width: 47.999rem) {
+  .app-shell {
+    grid-template-columns: minmax(0, 1fr);
+    grid-template-areas:
+      "header"
+      "content";
+  }
+
+  .app-shell__header {
+    padding-inline: 0.75rem;
+  }
+
+  .app-shell__menu-button {
+    display: inline-flex;
+  }
+
+  .app-shell__sidebar {
+    position: fixed;
+    z-index: 50;
+    top: 4.5rem;
+    bottom: 0;
+    left: 0;
+    display: none;
+    width: min(18rem, 85vw);
+    height: auto;
+    box-sizing: border-box;
+    box-shadow: 10px 0 30px color-mix(in oklch, var(--color-content) 15%, transparent);
+  }
+
+  .app-shell__sidebar[data-open="true"] {
+    display: block;
+  }
+
+  .app-shell__scrim {
+    position: fixed;
+    z-index: 40;
+    inset: 4.5rem 0 0;
+    display: block;
+    border: 0;
+    background: color-mix(in oklch, var(--color-content) 35%, transparent);
+    cursor: pointer;
+  }
+
+  .app-shell__session .session-status {
+    display: none;
+  }
+
+  .app-shell__brand {
+    display: none;
+  }
+
+  .readiness-grid {
+    grid-template-columns: minmax(0, 1fr);
+  }
+
+  .component-grid--two,
+  .component-grid--three {
+    grid-template-columns: minmax(0, 1fr);
+  }
 }
 
 @media (prefers-reduced-motion: reduce) {

tests/component/async-surface.test.jsx

@@ -59,8 +59,14 @@ describe("async UI state matrix", () => {
     const state = deriveAsyncState({ failure });
     render(<AsyncSurface state={state} />);
 
-    expect(screen.getByRole("alert")).toHaveTextContent(failure.userMessageKey);
-    expect(screen.getByRole("button")).toHaveTextContent("retry");
+    expect(screen.getByRole("alert")).toHaveTextContent(
+      "요청을 완료하지 못했습니다.",
+    );
+    expect(screen.getByRole("alert")).toHaveAttribute(
+      "data-message-key",
+      failure.userMessageKey,
+    );
+    expect(screen.getByRole("button")).toHaveTextContent("다시 시도");
     expect(screen.getByRole("alert")).not.toHaveTextContent("stack");
   });
 

tests/component/render-boundary.test.jsx

@@ -44,7 +44,13 @@ describe("render recovery boundaries", () => {
         <AsyncSurface state={state} />
       </FeatureBoundary>,
     );
-    expect(screen.getByRole("alert")).toHaveTextContent("error.server_failure");
+    expect(screen.getByRole("alert")).toHaveTextContent(
+      "요청을 완료하지 못했습니다.",
+    );
+    expect(screen.getByRole("alert")).toHaveAttribute(
+      "data-message-key",
+      "error.server_failure",
+    );
   });
 
   it("renders a safe boot shell with no endpoint or stack", () => {

tests/component/router.test.jsx

@@ -1,24 +1,72 @@
 // @vitest-environment jsdom
 
 import { render, screen } from "@testing-library/react";
+import userEvent from "@testing-library/user-event";
 import { describe, expect, it } from "vitest";
 
-import { createAnonymousSessionAdapter } from "../../src/adapters/auth/external-session-adapter.js";
+import {
+  createAnonymousSessionAdapter,
+  createDemoSessionAdapter,
+} from "../../src/adapters/auth/external-session-adapter.js";
 import { AppRouter } from "../../src/presentation/routes/app-router.jsx";
 
 describe("application router", () => {
-  it("renders not-found without making an API request", () => {
+  it("renders the app shell and not-found route without an API request", async () => {
     window.history.pushState({}, "", "/missing");
     render(<AppRouter authSession={createAnonymousSessionAdapter()} />);
+
     expect(
-      screen.getByRole("heading", { name: "페이지를 찾을 수 없습니다." }),
+      await screen.findByRole("heading", {
+        name: "페이지를 찾을 수 없습니다.",
+      }),
     ).toBeVisible();
+    expect(screen.getByRole("navigation", { name: "주요 탐색" })).toBeVisible();
+    expect(screen.getByRole("main")).toBeVisible();
   });
 
-  it("shows session-required UX without claiming authorization", () => {
+  it("navigates between registry-backed example routes", async () => {
+    const user = userEvent.setup();
+    window.history.pushState({}, "", "/");
+    render(<AppRouter authSession={createAnonymousSessionAdapter()} />);
+
+    await user.click(
+      await screen.findByRole("link", { name: "UI 구성요소", exact: true }),
+    );
+
+    expect(
+      await screen.findByRole("heading", { name: "UI 구성요소", level: 1 }),
+    ).toBeVisible();
+    expect(window.location.pathname).toBe("/examples/ui");
+  });
+
+  it("reacts to demo sign-in and opens the protected integration route", async () => {
+    const user = userEvent.setup();
+    const authSession = createDemoSessionAdapter();
+    window.history.pushState({}, "", "/sample/resources");
+    render(<AppRouter authSession={authSession} />);
+
+    expect(
+      await screen.findByRole("heading", { name: "세션이 필요합니다." }),
+    ).toBeVisible();
+    await user.click(screen.getByRole("button", { name: "로그인 시작" }));
+
+    expect(
+      await screen.findByRole("heading", { name: "보호된 연동 지점" }),
+    ).toBeVisible();
+    expect(screen.getByText("인증됨")).toBeVisible();
+  });
+
+  it("fails closed when the auth integration does not change state", async () => {
+    const user = userEvent.setup();
     window.history.pushState({}, "", "/sample/resources");
     render(<AppRouter authSession={createAnonymousSessionAdapter()} />);
-    expect(screen.getByRole("heading", { name: "세션이 필요합니다." })).toBeVisible();
-    expect(screen.getByRole("button", { name: "로그인" })).toBeVisible();
+
+    await user.click(
+      await screen.findByRole("button", { name: "로그인 시작" }),
+    );
+
+    expect(
+      screen.getByRole("heading", { name: "세션이 필요합니다." }),
+    ).toBeVisible();
   });
 });

tests/component/sample-resource-page.test.jsx

@@ -44,6 +44,11 @@ describe("removable sample feature page", () => {
     };
     render(<SampleResourcePage facade={facade} />);
 
-    expect(await screen.findByRole("alert")).toHaveTextContent("error.server_failure");
+    const alert = await screen.findByRole("alert");
+    expect(alert).toHaveTextContent("요청을 완료하지 못했습니다.");
+    expect(alert).toHaveAttribute(
+      "data-message-key",
+      "error.server_failure",
+    );
   });
 });

tests/component/ui-primitives.test.jsx

@@ -0,0 +1,108 @@
+// @vitest-environment jsdom
+
+import { render, screen, waitFor } from "@testing-library/react";
+import userEvent from "@testing-library/user-event";
+import { useState } from "react";
+import { describe, expect, it, vi } from "vitest";
+
+import { Alert } from "../../src/presentation/components/ui/alert.jsx";
+import { Badge } from "../../src/presentation/components/ui/badge.jsx";
+import { Button } from "../../src/presentation/components/ui/button.jsx";
+import { Card } from "../../src/presentation/components/ui/card.jsx";
+import { Dialog } from "../../src/presentation/components/ui/dialog.jsx";
+import { TextField } from "../../src/presentation/components/ui/text-field.jsx";
+
+describe("domain-neutral UI primitives", () => {
+  it("connects field help and validation errors to the input", () => {
+    render(
+      <TextField
+        label="이름"
+        description="표시할 이름입니다."
+        error="이름을 입력해 주세요."
+        required
+      />,
+    );
+
+    const field = screen.getByRole("textbox", { name: "이름" });
+    expect(field).toBeRequired();
+    expect(field).toHaveAccessibleDescription(
+      "표시할 이름입니다. 이름을 입력해 주세요.",
+    );
+    expect(field).toHaveAttribute("aria-invalid", "true");
+  });
+
+  it("exposes semantic variants without changing native button behavior", async () => {
+    const user = userEvent.setup();
+    const onClick = vi.fn();
+    render(
+      <>
+        <Button variant="danger" onClick={onClick}>
+          제거
+        </Button>
+        <Button disabled>사용 불가</Button>
+      </>,
+    );
+
+    await user.click(screen.getByRole("button", { name: "제거" }));
+    expect(onClick).toHaveBeenCalledOnce();
+    expect(screen.getByRole("button", { name: "제거" })).toHaveClass(
+      "ui-button--danger",
+    );
+    expect(screen.getByRole("button", { name: "사용 불가" })).toBeDisabled();
+  });
+
+  it("labels cards, alerts, and badges with visible content", async () => {
+    const user = userEvent.setup();
+    const dismiss = vi.fn();
+    render(
+      <Card title="상태 카드" footer={<Badge variant="success">준비됨</Badge>}>
+        <Alert title="저장됨" variant="success" onDismiss={dismiss}>
+          안전하게 반영했습니다.
+        </Alert>
+      </Card>,
+    );
+
+    expect(screen.getByRole("article", { name: "상태 카드" })).toBeVisible();
+    expect(screen.getByRole("status")).toHaveTextContent(
+      "저장됨안전하게 반영했습니다.",
+    );
+    expect(screen.getByText("준비됨")).toHaveClass("ui-badge--success");
+    await user.click(screen.getByRole("button", { name: "저장됨 알림 닫기" }));
+    expect(dismiss).toHaveBeenCalledOnce();
+  });
+
+  it("closes a modal and restores focus to its trigger", async () => {
+    const user = userEvent.setup();
+
+    function DialogHarness() {
+      const [open, setOpen] = useState(false);
+      return (
+        <>
+          <Button onClick={() => setOpen(true)}>모달 열기</Button>
+          <Dialog
+            open={open}
+            onClose={() => setOpen(false)}
+            title="연동 확인"
+            actions={<Button onClick={() => setOpen(false)}>확인</Button>}
+          >
+            안전한 설명
+          </Dialog>
+        </>
+      );
+    }
+
+    render(<DialogHarness />);
+    const trigger = screen.getByRole("button", { name: "모달 열기" });
+    await user.click(trigger);
+
+    expect(screen.getByRole("dialog", { name: "연동 확인" })).toHaveAttribute(
+      "open",
+    );
+    await user.click(screen.getByRole("button", { name: "확인" }));
+
+    await waitFor(() => expect(trigger).toHaveFocus());
+    expect(screen.getByRole("dialog", { hidden: true })).not.toHaveAttribute(
+      "open",
+    );
+  });
+});

tests/e2e/accessibility.spec.js

@@ -1,7 +1,14 @@
 import AxeBuilder from "@axe-core/playwright";
 import { expect, test } from "@playwright/test";
 
-for (const route of ["/", "/sample/resources", "/not-found"]) {
+for (const route of [
+  "/",
+  "/examples/ui",
+  "/examples/states",
+  "/examples/auth",
+  "/sample/resources",
+  "/not-found",
+]) {
   test(`@a11y ${route} has no critical or serious axe violations`, async ({
     page,
   }) => {
@@ -21,7 +28,7 @@ test("@a11y keyboard reaches the primary route action with visible focus", async
   page,
 }) => {
   await page.goto("/");
-  const action = page.getByRole("link", { name: "샘플 리소스" });
+  const action = page.getByRole("link", { name: "UI 구성요소 보기" });
   await expect(action).toBeVisible();
   await page.keyboard.press("Tab");
   await expect(action).toBeFocused();

tests/e2e/app-shell.spec.js

@@ -5,4 +5,51 @@ test("boots the public app shell", async ({ page }) => {
   await expect(page.getByRole("heading", { level: 1 })).toHaveText(
     "Clean Architecture Frontend",
   );
+  await expect(page.getByRole("navigation", { name: "주요 탐색" })).toBeVisible();
+  await expect(page.getByRole("main")).toBeVisible();
+});
+
+test("navigates to a registry-backed example without a page reload", async ({
+  page,
+}) => {
+  await page.goto("/");
+  await page
+    .getByRole("navigation", { name: "주요 탐색" })
+    .getByRole("link", { name: "화면 상태" })
+    .click();
+
+  await expect(page).toHaveURL(/\/examples\/states$/);
+  await expect(
+    page.getByRole("heading", { level: 1, name: "화면 상태" }),
+  ).toBeFocused();
+});
+
+test("opens the protected integration route through the local demo seam", async ({
+  page,
+}) => {
+  await page.goto("/sample/resources");
+  await expect(
+    page.getByRole("heading", { name: "세션이 필요합니다." }),
+  ).toBeVisible();
+
+  await page.getByRole("button", { name: "로그인 시작" }).click();
+
+  await expect(
+    page.getByRole("heading", { name: "보호된 연동 지점" }),
+  ).toBeVisible();
+  await expect(page.getByText("인증됨")).toBeVisible();
+});
+
+test("provides an escape-dismissible mobile navigation", async ({ page }) => {
+  await page.setViewportSize({ width: 390, height: 844 });
+  await page.goto("/");
+  const menu = page.getByRole("button", { name: "메뉴", exact: true });
+
+  await menu.click();
+  await expect(menu).toHaveAttribute("aria-expanded", "true");
+  await expect(page.getByRole("navigation", { name: "주요 탐색" })).toBeVisible();
+
+  await page.keyboard.press("Escape");
+  await expect(menu).toHaveAttribute("aria-expanded", "false");
+  await expect(page.getByRole("navigation", { name: "주요 탐색" })).toBeHidden();
 });

tests/e2e/theme.spec.js

@@ -0,0 +1,38 @@
+import AxeBuilder from "@axe-core/playwright";
+import { expect, test } from "@playwright/test";
+
+test("persists an explicit color scheme through the storage contract", async ({
+  page,
+}) => {
+  await page.goto("/");
+  const selector = page.getByRole("combobox", { name: "색상 테마" });
+
+  await selector.selectOption("dark");
+  await expect(page.locator("html")).toHaveAttribute("data-theme", "dark");
+  await expect(page.locator("html")).toHaveCSS("color-scheme", "dark");
+  const results = await new AxeBuilder({ page })
+    .withTags(["wcag2a", "wcag2aa", "wcag21a", "wcag21aa"])
+    .analyze();
+  expect(
+    results.violations.filter((violation) =>
+      ["critical", "serious"].includes(violation.impact ?? ""),
+    ),
+  ).toEqual([]);
+
+  await page.reload();
+  await expect(selector).toHaveValue("dark");
+  await expect(page.locator("html")).toHaveAttribute("data-theme", "dark");
+});
+
+test("tracks operating-system changes while system preference is selected", async ({
+  page,
+}) => {
+  await page.emulateMedia({ colorScheme: "dark" });
+  await page.goto("/");
+  const selector = page.getByRole("combobox", { name: "색상 테마" });
+  await selector.selectOption("system");
+  await expect(page.locator("html")).toHaveAttribute("data-theme", "dark");
+
+  await page.emulateMedia({ colorScheme: "light" });
+  await expect(page.locator("html")).toHaveAttribute("data-theme", "light");
+});

tests/e2e/ui-gallery.spec.js

@@ -0,0 +1,34 @@
+import { expect, test } from "@playwright/test";
+
+test("validates and reports the common text-field flow", async ({ page }) => {
+  await page.goto("/examples/ui");
+  await page.getByRole("button", { name: "입력 확인" }).click();
+
+  const field = page.getByRole("textbox", { name: "프로젝트 이름" });
+  await expect(field).toHaveAttribute("aria-invalid", "true");
+  await expect(field).toHaveAccessibleDescription(
+    /프로젝트 이름을 입력해 주세요/,
+  );
+
+  await field.fill("Starter");
+  await page.getByRole("button", { name: "입력 확인" }).click();
+  await expect(page.getByText("“Starter” 입력을 확인했습니다.")).toBeVisible();
+});
+
+test("traps modal interaction and restores focus to the trigger", async ({
+  page,
+}) => {
+  await page.goto("/examples/ui");
+  const trigger = page.getByRole("button", { name: "모달 열기" });
+  await trigger.click();
+
+  const dialog = page.getByRole("dialog", { name: "연동 확인" });
+  await expect(dialog).toBeVisible();
+  await expect(
+    dialog.getByRole("button", { name: "연동 확인 닫기" }),
+  ).toBeFocused();
+
+  await page.keyboard.press("Escape");
+  await expect(dialog).toBeHidden();
+  await expect(trigger).toBeFocused();
+});

tests/unit/color-scheme.test.js

@@ -0,0 +1,44 @@
+// @vitest-environment jsdom
+
+import { describe, expect, it } from "vitest";
+
+import {
+  normalizeColorSchemePreference,
+  resolveColorScheme,
+} from "../../src/application/policies/color-scheme.js";
+import { initializeColorScheme } from "../../src/bootstrap/initialize-color-scheme.js";
+
+describe("color scheme policy", () => {
+  it("normalizes unknown persisted values to the safe system default", () => {
+    expect(normalizeColorSchemePreference("sepia")).toBe("system");
+    expect(normalizeColorSchemePreference("dark")).toBe("dark");
+  });
+
+  it("resolves system and explicit preferences deterministically", () => {
+    expect(resolveColorScheme("system", true)).toBe("dark");
+    expect(resolveColorScheme("system", false)).toBe("light");
+    expect(resolveColorScheme("light", true)).toBe("light");
+  });
+
+  it("applies a persisted preference before application paint", () => {
+    const storage = {
+      read: () => ({ ok: true, value: "system" }),
+      write: () => ({ ok: true }),
+      remove: () => ({ ok: true }),
+    };
+
+    const result = initializeColorScheme(storage, {
+      documentElement: document.documentElement,
+      matchMedia: () =>
+        /** @type {MediaQueryList} */ ({ matches: true }),
+    });
+
+    expect(result).toEqual({ preference: "system", resolved: "dark" });
+    expect(document.documentElement).toHaveAttribute("data-theme", "dark");
+    expect(document.documentElement).toHaveAttribute(
+      "data-theme-preference",
+      "system",
+    );
+    expect(document.documentElement.style.colorScheme).toBe("dark");
+  });
+});

tests/unit/navigation-policy.test.js

@@ -4,7 +4,10 @@ import {
   createRedirectLoopGuard,
   decideRouteAccess,
 } from "../../src/presentation/routes/navigation-policy.js";
-import { ROUTE_REGISTRY } from "../../src/contracts/routes.js";
+import {
+  NAVIGATION_ROUTES,
+  ROUTE_REGISTRY,
+} from "../../src/contracts/routes.js";
 
 describe("route registry", () => {
   it("matches the stable registry snapshot", () => {
@@ -15,35 +18,93 @@ describe("route registry", () => {
           "chunkId": "route-home",
           "errorSurface": "route-boundary",
           "loadingSurface": "app-shell",
+          "navigationLabel": "시작",
+          "navigationOrder": 10,
           "paramsSchema": null,
           "path": "/",
           "routeId": "APP_HOME",
           "searchSchema": null,
+          "title": "시작",
+        },
+        "EXAMPLES_AUTH": {
+          "access": "public",
+          "chunkId": "route-examples-auth",
+          "errorSurface": "route-boundary",
+          "loadingSurface": "example-page",
+          "navigationLabel": "인증 연동",
+          "navigationOrder": 40,
+          "paramsSchema": null,
+          "path": "/examples/auth",
+          "routeId": "EXAMPLES_AUTH",
+          "searchSchema": null,
+          "title": "인증 연동",
+        },
+        "EXAMPLES_STATES": {
+          "access": "public",
+          "chunkId": "route-examples-states",
+          "errorSurface": "route-boundary",
+          "loadingSurface": "example-page",
+          "navigationLabel": "화면 상태",
+          "navigationOrder": 30,
+          "paramsSchema": null,
+          "path": "/examples/states",
+          "routeId": "EXAMPLES_STATES",
+          "searchSchema": null,
+          "title": "화면 상태",
+        },
+        "EXAMPLES_UI": {
+          "access": "public",
+          "chunkId": "route-examples-ui",
+          "errorSurface": "route-boundary",
+          "loadingSurface": "example-page",
+          "navigationLabel": "UI 구성요소",
+          "navigationOrder": 20,
+          "paramsSchema": null,
+          "path": "/examples/ui",
+          "routeId": "EXAMPLES_UI",
+          "searchSchema": null,
+          "title": "UI 구성요소",
         },
         "NOT_FOUND": {
           "access": "public",
           "chunkId": "route-not-found",
           "errorSurface": "not-found",
           "loadingSurface": "none",
+          "navigationLabel": null,
+          "navigationOrder": null,
           "paramsSchema": null,
           "path": "*",
           "routeId": "NOT_FOUND",
           "searchSchema": null,
+          "title": "페이지를 찾을 수 없음",
         },
         "SAMPLE_RESOURCE_LIST": {
           "access": "integration-defined",
           "chunkId": "route-sample-resources",
           "errorSurface": "feature-boundary",
           "loadingSurface": "sample-resource-list",
+          "navigationLabel": "보호된 연동 지점",
+          "navigationOrder": 50,
           "paramsSchema": null,
           "path": "/sample/resources",
           "routeId": "SAMPLE_RESOURCE_LIST",
           "searchSchema": "SampleResourceListQuery",
+          "title": "보호된 연동 지점",
         },
       }
     `);
   });
 
+  it("derives visible navigation in explicit order", () => {
+    expect(NAVIGATION_ROUTES.map(({ routeId }) => routeId)).toEqual([
+      "APP_HOME",
+      "EXAMPLES_UI",
+      "EXAMPLES_STATES",
+      "EXAMPLES_AUTH",
+      "SAMPLE_RESOURCE_LIST",
+    ]);
+  });
+
   it("treats client access as a UX hint, not authorization", () => {
     expect(decideRouteAccess("APP_HOME", "unauthenticated")).toEqual({
       allowed: true,