diff --git a/src/HSchool.Client/vite.config.ts b/src/HSchool.Client/vite.config.ts
index 49920f7..40abb17 100644
--- a/src/HSchool.Client/vite.config.ts
+++ b/src/HSchool.Client/vite.config.ts
@@ -10,6 +10,9 @@ const tailscaleServe = process.env.HSCHOOL_TAILSCALE_SERVE === '1';
 
 export default defineConfig({
   server: {
+    // Serve proxies to 127.0.0.1:5173. Default `localhost` binds [::1] only on
+    // Windows, so Tailscale gets connection refused and the browser shows 502.
+    host: '127.0.0.1',
     port: 5173,
     strictPort: true,
     allowedHosts: ['.ts.net'],