Izmjenjen backend

backend/app.js

@@ -0,0 +1,10 @@
+const express = require('express')
+const app = express()
+
+app.get('/', function (req, res) {
+  res.send('Hello World!')
+})
+
+app.listen(3000, function () {
+  console.log('Example app listening on port 3000!')
+})