Can't unlock or shut down

[CD Sailor]

Got a message concerning backing up to iCloud. Hit OK to get rid of it and nothing happened. Now I can't even unlock or
reboot. Any ideas? This is a first for me.

 

[J. A.76]

Got a message concerning backing up to iCloud. Hit OK to get rid of it and nothing happened. Now I can't even unlock or
reboot. Any ideas? This is a first for me.

Reset your iPad: press and hold Home and Power button at the same time until the Apple logo appears.