This build has its own tuning - a 6×11 brick wall and a paddle tuned to 27% of the screen. Your progress and best score are saved locally on your device.
Your best score is stored in your browser's local storage, so it survives refreshes. Clearing site data resets it.
Once the page has loaded, most of it keeps working without a connection, but for the cleanest experience play with the page freshly loaded.