diff --git a/src/App.jsx b/src/App.jsx
index 5a11b48..0c39e36 100644
--- a/src/App.jsx
+++ b/src/App.jsx
@@ -1,4 +1,4 @@
-import { lazy, Suspense, useEffect, useMemo, useState } from "react";
+import { useEffect, useMemo, useState } from "react";
 import { Navigate, Outlet, Route, Routes, useLocation, useNavigate } from "react-router-dom";
 import { getMenus } from "./api/navigation.js";
 import { useAuth } from "./auth/AuthProvider.jsx";
@@ -7,47 +7,72 @@ import { PageSkeleton } from "./components/layout/PageSkeleton.jsx";
 import { Sidebar } from "./components/layout/Sidebar.jsx";
 import { findNavItemByPath, mapBackendMenus, navItems } from "./constants/navigation.js";
 
-const LoginPage = lazy(() => import("./pages/LoginPage.jsx").then((module) => ({ default: module.LoginPage })));
-const OverviewPage = lazy(() => import("./pages/OverviewPage.jsx").then((module) => ({ default: module.OverviewPage })));
-const ServicesPage = lazy(() => import("./pages/ServicesPage.jsx").then((module) => ({ default: module.ServicesPage })));
-const UserManagementPage = lazy(() =>
-  import("./pages/UserManagementPage.jsx").then((module) => ({ default: module.UserManagementPage }))
-);
-const RoleManagementPage = lazy(() =>
-  import("./pages/RoleManagementPage.jsx").then((module) => ({ default: module.RoleManagementPage }))
-);
-const MenuManagementPage = lazy(() =>
-  import("./pages/MenuManagementPage.jsx").then((module) => ({ default: module.MenuManagementPage }))
-);
-const LogsPage = lazy(() => import("./pages/LogsPage.jsx").then((module) => ({ default: module.LogsPage })));
-const NotificationsPage = lazy(() =>
-  import("./pages/NotificationsPage.jsx").then((module) => ({ default: module.NotificationsPage }))
-);
+const pageModules = {
+  login: () => import("./pages/LoginPage.jsx").then((module) => module.LoginPage),
+  overview: () => import("./pages/OverviewPage.jsx").then((module) => module.OverviewPage),
+  services: () => import("./pages/ServicesPage.jsx").then((module) => module.ServicesPage),
+  users: () => import("./pages/UserManagementPage.jsx").then((module) => module.UserManagementPage),
+  roles: () => import("./pages/RoleManagementPage.jsx").then((module) => module.RoleManagementPage),
+  menus: () => import("./pages/MenuManagementPage.jsx").then((module) => module.MenuManagementPage),
+  logs: () => import("./pages/LogsPage.jsx").then((module) => module.LogsPage),
+  notifications: () => import("./pages/NotificationsPage.jsx").then((module) => module.NotificationsPage)
+};
+
+const pageCache = new Map();
 
 function App() {
   return (
-    <Suspense fallback={<PageSkeleton />}>
-      <Routes>
-        <Route path="/login" element={<LoginPage />} />
-        <Route element={<RequireAuth />}>
-          <Route element={<AdminLayout />}>
-            <Route index element={<Navigate to="/overview" replace />} />
-            <Route path="/overview" element={<RequirePermission code="overview:view"><OverviewPage /></RequirePermission>} />
-            <Route path="/services" element={<RequirePermission code="service:view"><ServicesPage /></RequirePermission>} />
-            <Route path="/system/users" element={<RequirePermission code="user:view"><UserManagementPage /></RequirePermission>} />
-            <Route path="/system/roles" element={<RequirePermission code="role:view"><RoleManagementPage /></RequirePermission>} />
-            <Route path="/system/menus" element={<RequirePermission code="menu:view"><MenuManagementPage /></RequirePermission>} />
-            <Route path="/logs/login" element={<RequirePermission code="log:view"><LogsPage type="login" /></RequirePermission>} />
-            <Route path="/logs/operations" element={<RequirePermission code="log:view"><LogsPage type="operations" /></RequirePermission>} />
-            <Route path="/notifications" element={<RequirePermission code="notification:view"><NotificationsPage /></RequirePermission>} />
-          </Route>
+    <Routes>
+      <Route path="/login" element={<DeferredPage pageKey="login" />} />
+      <Route element={<RequireAuth />}>
+        <Route element={<AdminLayout />}>
+          <Route index element={<Navigate to="/overview" replace />} />
+          <Route path="/overview" element={<RequirePermission code="overview:view"><DeferredPage pageKey="overview" /></RequirePermission>} />
+          <Route path="/services" element={<RequirePermission code="service:view"><DeferredPage pageKey="services" /></RequirePermission>} />
+          <Route path="/system/users" element={<RequirePermission code="user:view"><DeferredPage pageKey="users" /></RequirePermission>} />
+          <Route path="/system/roles" element={<RequirePermission code="role:view"><DeferredPage pageKey="roles" /></RequirePermission>} />
+          <Route path="/system/menus" element={<RequirePermission code="menu:view"><DeferredPage pageKey="menus" /></RequirePermission>} />
+          <Route path="/logs/login" element={<RequirePermission code="log:view"><DeferredPage pageKey="logs" type="login" /></RequirePermission>} />
+          <Route path="/logs/operations" element={<RequirePermission code="log:view"><DeferredPage pageKey="logs" type="operations" /></RequirePermission>} />
+          <Route path="/notifications" element={<RequirePermission code="notification:view"><DeferredPage pageKey="notifications" /></RequirePermission>} />
         </Route>
-        <Route path="*" element={<Navigate to="/overview" replace />} />
-      </Routes>
-    </Suspense>
+      </Route>
+      <Route path="*" element={<Navigate to="/overview" replace />} />
+    </Routes>
   );
 }
 
+function DeferredPage({ pageKey, ...props }) {
+  const [Page, setPage] = useState(() => pageCache.get(pageKey) || null);
+
+  useEffect(() => {
+    let mounted = true;
+
+    if (pageCache.has(pageKey)) {
+      setPage(() => pageCache.get(pageKey));
+      return undefined;
+    }
+
+    setPage(null);
+    pageModules[pageKey]().then((component) => {
+      pageCache.set(pageKey, component);
+      if (mounted) {
+        setPage(() => component);
+      }
+    });
+
+    return () => {
+      mounted = false;
+    };
+  }, [pageKey]);
+
+  if (!Page) {
+    return <PageSkeleton />;
+  }
+
+  return <Page {...props} />;
+}
+
 function RequireAuth() {
   const { loading, user } = useAuth();
   const location = useLocation();
@@ -118,11 +143,9 @@ function AdminLayout() {
         <Sidebar activePath={location.pathname} isCollapsed={sidebarCollapsed} items={menus} onNavigate={navigate} />
 
         <main className="workspace">
-          <Suspense fallback={<PageSkeleton />}>
-            <div className="page-transition" key={location.pathname}>
-              <Outlet context={{ refreshTick }} />
-            </div>
-          </Suspense>
+          <div className="page-transition" key={location.pathname}>
+            <Outlet context={{ refreshTick }} />
+          </div>
         </main>
       </div>
     </div>
diff --git a/src/components/layout/Sidebar.jsx b/src/components/layout/Sidebar.jsx
index 53e7a2d..e501d8c 100644
--- a/src/components/layout/Sidebar.jsx
+++ b/src/components/layout/Sidebar.jsx
@@ -125,23 +125,25 @@ function NavGroup({
         {hasChildren ? <ExpandMore className="nav-expand" fontSize="small" /> : null}
       </button>
 
-      {hasChildren && isOpen && !isCollapsed ? (
-        <div className="nav-children">
-          {children.map((child) => {
-            const ChildIcon = child.icon;
+      {hasChildren && !isCollapsed ? (
+        <div className={`nav-children ${isOpen ? "nav-children--open" : ""}`}>
+          <div className="nav-children__inner">
+            {children.map((child) => {
+              const ChildIcon = child.icon;
 
-            return (
-              <button
-                className={`nav-item nav-item--child ${child.path && activePath.startsWith(child.path) ? "nav-item--active" : ""}`}
-                key={child.id}
-                type="button"
-                onClick={() => onNavigate(child.path)}
-              >
-                <ChildIcon fontSize="small" />
-                <span className="nav-label">{child.label}</span>
-              </button>
-            );
-          })}
+              return (
+                <button
+                  className={`nav-item nav-item--child ${child.path && activePath.startsWith(child.path) ? "nav-item--active" : ""}`}
+                  key={child.id}
+                  type="button"
+                  onClick={() => onNavigate(child.path)}
+                >
+                  <ChildIcon fontSize="small" />
+                  <span className="nav-label">{child.label}</span>
+                </button>
+              );
+            })}
+          </div>
         </div>
       ) : null}
 
diff --git a/src/pages/UserManagementPage.jsx b/src/pages/UserManagementPage.jsx
index 2b4330b..5cea24b 100644
--- a/src/pages/UserManagementPage.jsx
+++ b/src/pages/UserManagementPage.jsx
@@ -322,7 +322,7 @@ export function UserManagementPage() {
           </div>
           <FormControlLabel
             control={<Switch checked={form.mfaEnabled} onChange={(event) => setForm({ ...form, mfaEnabled: event.target.checked })} />}
-            label="MFA 已开启"
+            label={form.mfaEnabled ? "MFA 已开启" : "MFA 未开启"}
           />
           <div className="form-drawer__actions">
             <Button onClick={() => setFormOpen(false)}>取消</Button>
diff --git a/src/styles/app.css b/src/styles/app.css
index c6410a2..dabc836 100644
--- a/src/styles/app.css
+++ b/src/styles/app.css
@@ -374,13 +374,31 @@
 }
 
 .app-shell--sidebar-collapsed .brand {
+  gap: 0;
   justify-content: center;
   padding: 0;
 }
 
+.brand-text,
+.nav-label {
+  display: inline-grid;
+  min-width: 0;
+  max-width: 160px;
+  opacity: 1;
+  overflow: hidden;
+  transform: translateX(0);
+  transition:
+    max-width var(--motion-slow) var(--ease-emphasized),
+    opacity var(--motion-base) var(--ease-standard),
+    transform var(--motion-base) var(--ease-emphasized);
+}
+
 .app-shell--sidebar-collapsed .brand-text,
 .sidebar--collapsed .nav-label {
-  display: none;
+  max-width: 0;
+  opacity: 0;
+  pointer-events: none;
+  transform: translateX(-6px);
 }
 
 .sidebar--collapsed {
@@ -421,6 +439,9 @@
   transition:
     background var(--motion-base) var(--ease-standard),
     color var(--motion-base) var(--ease-standard),
+    gap var(--motion-slow) var(--ease-emphasized),
+    padding var(--motion-slow) var(--ease-emphasized),
+    width var(--motion-slow) var(--ease-emphasized),
     transform var(--motion-base) var(--ease-emphasized);
 }
 
@@ -452,8 +473,30 @@
 
 .nav-children {
   display: grid;
-  gap: 4px;
+  grid-template-rows: 0fr;
+  opacity: 0;
+  overflow: hidden;
   padding-left: 20px;
+  pointer-events: none;
+  transform: translateY(-4px);
+  transition:
+    grid-template-rows var(--motion-slow) var(--ease-emphasized),
+    opacity var(--motion-base) var(--ease-standard),
+    transform var(--motion-slow) var(--ease-emphasized);
+}
+
+.nav-children--open {
+  grid-template-rows: 1fr;
+  opacity: 1;
+  pointer-events: auto;
+  transform: translateY(0);
+}
+
+.nav-children__inner {
+  display: grid;
+  gap: 4px;
+  min-height: 0;
+  overflow: hidden;
 }
 
 .nav-item--child {
diff --git a/src/theme.js b/src/theme.js
index 4d1b10a..124f791 100644
--- a/src/theme.js
+++ b/src/theme.js
@@ -144,6 +144,59 @@ export const theme = createTheme({
         }
       }
     },
+    MuiSwitch: {
+      defaultProps: {
+        disableRipple: true
+      },
+      styleOverrides: {
+        root: {
+          width: 46,
+          height: 26,
+          padding: 0,
+          margin: "0 8px",
+          overflow: "visible"
+        },
+        switchBase: {
+          padding: 3,
+          color: "#ffffff",
+          transition: "transform 220ms cubic-bezier(0.16, 1, 0.3, 1)",
+          "&.Mui-checked": {
+            color: "#ffffff",
+            transform: "translateX(20px)",
+            "& + .MuiSwitch-track": {
+              borderColor: "rgba(37, 99, 235, 0.36)",
+              background: "linear-gradient(135deg, #2563eb, #0ea5e9)",
+              boxShadow: "0 8px 20px rgba(37, 99, 235, 0.22)",
+              opacity: 1
+            },
+            "& .MuiSwitch-thumb": {
+              boxShadow: "0 4px 12px rgba(15, 23, 42, 0.18)"
+            }
+          },
+          "&.Mui-disabled": {
+            color: "#ffffff",
+            "& + .MuiSwitch-track": {
+              opacity: 0.5
+            }
+          }
+        },
+        thumb: {
+          width: 20,
+          height: 20,
+          backgroundColor: "#ffffff",
+          boxShadow: "0 3px 10px rgba(15, 23, 42, 0.18)"
+        },
+        track: {
+          border: "1px solid #d8e0ec",
+          borderRadius: 999,
+          backgroundColor: "#e2e8f0",
+          boxShadow: "inset 0 1px 2px rgba(15, 23, 42, 0.06)",
+          opacity: 1,
+          transition:
+            "background 220ms cubic-bezier(0.2, 0, 0, 1), border-color 220ms cubic-bezier(0.2, 0, 0, 1), box-shadow 220ms cubic-bezier(0.2, 0, 0, 1)"
+        }
+      }
+    },
     MuiOutlinedInput: {
       styleOverrides: {
         notchedOutline: {