How delicate is the uno?

Hi all
I’m just starting and was doing the push button project on page 45 of the beginner guid. The led blinked when button was pressed. I then held the button down to see the light stay on
But now my board is dead. Totally dead no lights can’t program it nothing
Are these board that fragile??

Thanks

Found mine to be quite resiliant.

However there are caveats to that.
Short circuit it for even the shortest time and most often you can kiss it goodbye.
Overload a pin too long then as above.

As with any "open board electronics" there are quite a few basic steps to take.

Keep metallic objects away from the board.
Keep liquids away from the board.
Dont change things around with the board powered up.
Know the limits of the board and other attached items BEFORE you even think of plugging anything into it.
Double and triple check your wiring BEFORE applying power.
Dont try bend or stretch components or wires if they are not long enough stop and re-work your circuit.

There are lots more but those are the absolute minimum