Documentation section gives an error of 502 with offline message:
This page (https://docs.nopcommerce.com/display/en/Setting+up+Payments) is currently offline. However, because the site uses Cloudflare's Always Online™ technology you can continue to surf a snapshot of the site. We will keep checking in the background and, as soon as the site comes back, you will automatically be served the live version.
On maintenance?
Where is a snapshot of the site?