After Idle Do x

I want to essentially make a game start screen, when no button is pressed for x time, it starts playing a video. However, while I can get it to start the video I don’t know how to reset the idle back to 0 after a button is pressed.

I tried coding this and I have actually deleted that portion of code since then.

rough code, not tested.

if(Input.GetAnyKey)
{
    idletime = 0;
}