增加基础应用结构。

src/pages/MainLayout.module.css

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+@layer pages {
+  .main_layout {
+    height: 100%;
+    width: 100%;
+    overflow: hidden;
+    display: flex;
+    flex-direction: row;
+    justify-content: flex-start;
+    align-items: stretch;
+  }
+  .content {
+    flex: 1 0;
+  }
+}

src/pages/MainLayout.tsx

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+import { Outlet } from 'react-router-dom';
+import { NavigationMenu } from '../page-components/navigation/NavigationMenu';
+import styles from './MainLayout.module.css';
+
+export function MainLayout() {
+  return (
+    <div className={styles.main_layout}>
+      <NavigationMenu />
+      <div className={styles.content}>
+        <Outlet />
+      </div>
+    </div>
+  );
+}