You need to edit the pihlaja-script.js to fit your needs. That file is mostly full of examples .
In the example file, device 11 is a weather device. If you have a weather device, you can change the id(11) to what you have. devices[number][“attributes”].value will return temperature value (example: 23).
When you start the page, you should get an ARRAY of json in Developer console. there you can see which ID your device is given.