Apple iOS restrictions prevent regular Safari webpages from hiding the URL bar programmatically. To hide all browser bars permanently:
1. Tap Safari's Share button (square with arrow ⎋ at top of screen).
2. Tap "Add to Home Screen".
3. Tap Add, then open the new Home icon on your iPad home screen.
It will now launch as a true standalone fullscreen app with zero URL bars, tabs, or buttons!