The screen doesn't react no more, so how come is the body??
Could you still backup your data via cable to PC? Please try to backup your data and follow steps below to access recovery mode.
1. Keep pressing "volume down key"
2. Press "power key" and stop press " power key" once you feel the vibration
3. Still keep pressing "volume down key" and stop press "volume down key" once you enter [Android Recovery] Screen
4. Choose "Wipe data/factory reset"
#Hardware Reset Guide