text: const express = require('express');
  const app = express();
  const port = process.env.PORT || 5000;
  const myLiffId = process.env.MY_LIFF_ID;
  
  app.use(express.static('public'));
  
  app.get('/send-id', function(req, res) {
      res.json({id: myLiffId});
  });
  
  app.listen(port, () => console.log(`app listening on port ${port}!`));