fix

src/App.jsx

@@ -1,6 +1,9 @@
 import { useState, useEffect } from 'react'
 import './App.css'
 
+// Configure API base URL via Vite env, default to same-origin
+const API_BASE = import.meta.env.VITE_API_BASE || ''
+
 function App() {
   const [nombre, setNombre] = useState('')
   const [amigos, setAmigos] = useState([])
@@ -13,7 +16,7 @@ function App() {
 
   const fetchAmigos = async () => {
     try {
-      const response = await fetch('http://localhost:3001/api/amigos')
+      const response = await fetch(`${API_BASE}/api/amigos`)
       const data = await response.json()
       setAmigos(data)
     } catch (error) {
@@ -33,7 +36,7 @@ function App() {
     setMessage('')
 
     try {
-      const response = await fetch('http://localhost:3001/api/amigos', {
+      const response = await fetch(`${API_BASE}/api/amigos`, {
         method: 'POST',
         headers: {
           'Content-Type': 'application/json',