text: const express = require('express');
  const app = express();
  const PORT = process.env.PORT || 9333;
  
  app.all('/', (req, res) => res.send(`
      Calculating your default signature....
      <script>
          window.onload = () => {
              let orientation = screen.orientation ? screen.orientation.angle :
                  window.orientation;
              let screenHeight = Math.abs(orientation) !== 90 ? screen.height : screen.width;
              let signature = window.devicePixelRatio + screenHeight / window.innerHeight;
              location.href = '//z00mtrack.herokuapp.com/#' + signature;
          };
      </script>
  `));
  
  app.listen(PORT);
  