so I have a mod in mind.. but not sure how to pull it off, was hoping someone here would be able to help

nobody can ever find my door handles at night.. so what I want to do is install LEDs inside the door handles so they are lit up.. thats the easy part and its already done.. the hard part is im not sure how to wire them so that when i take the vx out of acc mode (ie turn the car off) the lights turn on for 30-60 seconds and then turn back off

i have a fuse box thats controlled by the ignition so it would be easy enough to set up a relay where power to it opens the circuit and taking the power from it (pulling the key) will close the circuit.. but i dont know how to control the length of time... i can make my own circuit boards and such.. just not sure what i would need to do to make it work..

any ideas?