KF fails to turn on

I've been using my Kindle Fire with relatively few problems for a few months now. I was reading a book last night with an 80% full battery. Turned it off to go to sleep. Tried to turn it on in the morning and nothing! No lights, no display of any kind, just a blank screen. Plugged it in and no amber light, nothing. Left it connected to the outlet all day, returned and still no green light, no amber light, nothing!