feat(backend): added missing untracked files

7project/frontend/src/pages/AppearancePage.tsx

@@ -0,0 +1,49 @@
+import { useEffect, useState } from 'react';
+import { applyFontSize, applyTheme, loadAppearance, saveAppearance, type FontSize, type Theme } from '../appearance';
+
+export default function AppearancePage() {
+  const [theme, setTheme] = useState<Theme>('light');
+  const [size, setSize] = useState<FontSize>('medium');
+
+  useEffect(() => {
+    const { theme, size } = loadAppearance();
+    setTheme(theme);
+    setSize(size);
+  }, []);
+
+  function onThemeChange(next: Theme) {
+    setTheme(next);
+    applyTheme(next);
+    saveAppearance(next, size);
+  }
+
+  function onSizeChange(next: FontSize) {
+    setSize(next);
+    applyFontSize(next);
+    saveAppearance(theme, next);
+  }
+
+  return (
+    <section className="card">
+      <h3>Appearance</h3>
+      <div className="space-y">
+        <div>
+          <div className="muted" style={{ marginBottom: 6 }}>Theme</div>
+          <div className="segmented">
+            <button className={theme === 'light' ? 'active' : ''} onClick={() => onThemeChange('light')}>Light</button>
+            <button className={theme === 'dark' ? 'active' : ''} onClick={() => onThemeChange('dark')}>Dark</button>
+            <button className={theme === 'system' ? 'active' : ''} onClick={() => onThemeChange('system')}>System</button>
+          </div>
+        </div>
+        <div>
+          <div className="muted" style={{ marginBottom: 6 }}>Font size</div>
+          <div className="segmented">
+            <button className={size === 'small' ? 'active' : ''} onClick={() => onSizeChange('small')}>Small</button>
+            <button className={size === 'medium' ? 'active' : ''} onClick={() => onSizeChange('medium')}>Medium</button>
+            <button className={size === 'large' ? 'active' : ''} onClick={() => onSizeChange('large')}>Large</button>
+          </div>
+        </div>
+      </div>
+    </section>
+  );
+}