How to delay device shutdown?

Question

Electronic components

There is a device with a power supply of 2.86v when the button is pressed, the circuit closes for a fraction of a second, but you need to make sure that the circuit closing time is about ¼ second. I understand that this can be implemented at the expense of a time relay, but everything depends on the size. The resulting device should be small enough (no more than 10*10*5mm). Below is an example wiring diagram.

Answer 1

It will probably be big though.