Chosen Solution
I had the battery fully charged and while surfing, it switched off and I can’t restart it. Happy for any hint before going to a repair shop. Thank you!
Have you tried a hard reset? Press and hold power and home button for 20 to 30 seconds and see if it starts.
you may need to open up the iPad if nothing else software-wise works. you could remove the front glass. the problem may be because of the battery or maybe the screen ? if there is anything else causing it, look at the iPad repair guide on iFixit.
