add config.js to allow for changing api url depending on environment

src/App.jsx

@@ -1,4 +1,5 @@
 import { useEffect, useState } from "react";
+import config from "./config";
 import reactLogo from "./assets/react.svg";
 import viteLogo from "/vite.svg";
 import "./App.css";
@@ -8,7 +9,7 @@ function App() {
   const [questions, setQuestions] = useState([]);
 
   useEffect(() => {
-    fetch("http://localhost:3000/api/questions/random")
+    fetch(`${config.apiBaseUrl}/api/questions/random`)
       .then((res) => res.json())
       .then(
         (data) => {

src/config.js

@@ -0,0 +1,13 @@
+let config;
+
+if (window.location.hostname === "localhost") {
+  config = {
+    apiBaseUrl: "http://localhost:3000",
+  };
+} else {
+  config = {
+    apiBaseUrl: "https://api.example.com",
+  };
+}
+
+export default config;