problem in downloading esp8266 files to my ARDUINO IDE 1.8.2

I have esp8266 with me i am not able to download esp8266 files
from this website ( http://arduino.esp8266.com/stable/package_esp8266com_index.json)
it shows like error during download please help me out

error is like
no protocol: http://arduino.esp8266.com/stable/package_esp8266com_index.json

this is how it shows(In serial window) when i try to Install ESP8266 Platform

The ESP site is notorious at going down.

All you can really do is wait until it is back up as it is not directly related to Arduino.