I have a query about the mind boggles? It's too hard to understand for English learner. so what does mean the mind boggles?
"Mind-boggling" or to "boggle your mind" is an expression that means overwhelming, startling, amazing, or astonishing.
Here is a definition:
having a very powerful or overwhelming effect on the mind
a mind-boggling [=stunning] performance
amazingly or confusingly large, great, etc.
a mind-boggling array of options
He received a mind-boggling $200 million in pay.
The sheer vastness of space is mind-boggling.