diff --git a/src/components/common/GlobalLoadingWrapper.jsx b/src/components/common/GlobalLoadingWrapper.jsx
new file mode 100644
index 0000000..9c843a7
--- /dev/null
+++ b/src/components/common/GlobalLoadingWrapper.jsx
@@ -0,0 +1,32 @@
+import { useNavigation } from 'react-router-dom';
+import { useSelector } from 'react-redux';
+import Spinner from './Spinner';
+
+const selectIsAnyLoading = (state) =>
+  state.auth.isLoading ||
+  state.campaigns.loading ||
+  state.donations.loading ||
+  state.dashboard.loading;
+
+const GlobalLoadingWrapper = ({ children }) => {
+  const navigation = useNavigation();
+  const isReduxLoading = useSelector(selectIsAnyLoading);
+
+  const isLoading = navigation.state !== 'idle' || isReduxLoading;
+
+  return (
+    <>
+      {children}
+      {isLoading && (
+        <div
+          aria-busy="true"
+          className="fixed inset-0 z-50 flex items-center justify-center bg-white/60 backdrop-blur-sm"
+        >
+          <Spinner size="lg" className="text-accent" />
+        </div>
+      )}
+    </>
+  );
+};
+
+export default GlobalLoadingWrapper;
diff --git a/src/pages/NotFound.jsx b/src/pages/NotFound.jsx
index 3e0d3fb..153b9ff 100644
--- a/src/pages/NotFound.jsx
+++ b/src/pages/NotFound.jsx
@@ -1,11 +1,40 @@
-import { Link } from 'react-router-dom';
+import { Link, useNavigate } from 'react-router-dom';
 
 const NotFound = () => {
+  const navigate = useNavigate();
+
   return (
-    <div style={{ textAlign: 'center', marginTop: '50px' }}>
-      <h1>404 - Page Not Found</h1>
-      <p>The page you are looking for does not exist.</p>
-      <Link to="/" style={{ color: 'blue', textDecoration: 'underline' }}>Go back to Home</Link>
+    <div className="min-h-screen bg-white flex flex-col items-center justify-center px-6 text-center animate-fade-in">
+      <div className="max-w-md w-full">
+        <p className="text-[9rem] font-bold leading-none text-accent select-none">
+          404
+        </p>
+
+        <h1 className="mt-2 text-2xl font-semibold text-primary">
+          Page Not Found
+        </h1>
+
+        <p className="mt-3 text-slate-500 text-sm leading-relaxed">
+          The page you&apos;re looking for doesn&apos;t exist or may have been moved.
+          Check the URL or head back home.
+        </p>
+
+        <div className="mt-8 flex flex-col sm:flex-row items-center justify-center gap-3">
+          <Link
+            to="/"
+            className="w-full sm:w-auto inline-flex items-center justify-center gap-2 bg-accent hover:bg-indigo-600 active:bg-indigo-700 text-white font-medium px-6 py-3 rounded-lg transition-colors duration-150"
+          >
+            Go Back Home
+          </Link>
+
+          <button
+            onClick={() => navigate(-1)}
+            className="w-full sm:w-auto inline-flex items-center justify-center gap-2 bg-white hover:bg-slate-50 active:bg-slate-100 text-primary font-medium px-6 py-3 rounded-lg border border-slate-200 hover:border-slate-300 transition-colors duration-150"
+          >
+            Go Back
+          </button>
+        </div>
+      </div>
     </div>
   );
 };
diff --git a/src/routes/AppRouter.jsx b/src/routes/AppRouter.jsx
index a41a5e1..027afad 100644
--- a/src/routes/AppRouter.jsx
+++ b/src/routes/AppRouter.jsx
@@ -1,41 +1,53 @@
+import { lazy, Suspense } from 'react';
 import { BrowserRouter, Routes, Route } from 'react-router-dom';
 
-// Layout
 import MainLayout from '../components/layout/MainLayout';
+import GlobalLoadingWrapper from '../components/common/GlobalLoadingWrapper';
+import Spinner from '../components/common/Spinner';
+import NotFound from '../pages/NotFound';
+import ErrorTest from '../components/common/ErrorTest';
 
-// Pages
-import Home from '../pages/Home';
-import Explore from '../pages/Explore';
+// Auth pages — small, kept as static imports
 import Login from '../pages/Login';
 import Register from '../pages/Register';
 import ForgotPasswordPage from '../pages/auth/ForgotPasswordPage';
-import Dashboard from '../pages/Dashboard';
-import CampaignDetails from '../pages/CampaignDetails';
-import CreateCampaign from '../pages/CreateCampaign';
-import Admin from '../pages/Admin';
-import NotFound from '../pages/NotFound';
 
-// Test Component
-import ErrorTest from '../components/common/ErrorTest';
+// Main pages — lazy-loaded for code splitting
+const Home = lazy(() => import('../pages/Home'));
+const Explore = lazy(() => import('../pages/Explore'));
+const CampaignDetails = lazy(() => import('../pages/CampaignDetails'));
+const CreateCampaign = lazy(() => import('../pages/CreateCampaign'));
+const Dashboard = lazy(() => import('../pages/Dashboard'));
+const Admin = lazy(() => import('../pages/Admin'));
+
+const SuspenseFallback = () => (
+  <div className="flex min-h-screen items-center justify-center">
+    <Spinner size="lg" className="text-accent" />
+  </div>
+);
 
 const AppRouter = () => {
   return (
     <BrowserRouter>
-      <Routes>
-          <Route path="register" element={<Register />} />
-          <Route path="login" element={<Login />} />
-          <Route path="forgot-password" element={<ForgotPasswordPage />} />
-          <Route path="admin" element={<Admin />} />
-          <Route path="dashboard" element={<Dashboard />} />
-          <Route path="*" element={<NotFound />} />
-        <Route path="/" element={<MainLayout />}>
-          <Route index element={<Home />} />
-          <Route path="explore" element={<Explore />} />
-          <Route path="campaign/:id" element={<CampaignDetails />} />
-          <Route path="create" element={<CreateCampaign />} />
-          <Route path="test-error" element={<ErrorTest />} />
-        </Route>
-      </Routes>
+      <GlobalLoadingWrapper>
+        <Suspense fallback={<SuspenseFallback />}>
+          <Routes>
+            <Route path="register" element={<Register />} />
+            <Route path="login" element={<Login />} />
+            <Route path="forgot-password" element={<ForgotPasswordPage />} />
+            <Route path="admin" element={<Admin />} />
+            <Route path="dashboard" element={<Dashboard />} />
+            <Route path="*" element={<NotFound />} />
+            <Route path="/" element={<MainLayout />}>
+              <Route index element={<Home />} />
+              <Route path="explore" element={<Explore />} />
+              <Route path="campaign/:id" element={<CampaignDetails />} />
+              <Route path="create" element={<CreateCampaign />} />
+              <Route path="test-error" element={<ErrorTest />} />
+            </Route>
+          </Routes>
+        </Suspense>
+      </GlobalLoadingWrapper>
     </BrowserRouter>
   );
 };