Russian-Byzantine architecture is a type of building design that was used in Russia a long time ago. It is a special style that was inspired by the way buildings in the Byzantine Empire were built. The Byzantine Empire was a big and powerful empire that existed a long, long time ago.
The buildings that were made using the Russian-Byzantine style are very big and have very tall domes. The domes are like round roofs that are bigger than regular roofs. The buildings are also decorated with lots of colorful paintings and designs that are meant to look very beautiful.
The people who built these buildings were very skilled, and they used special techniques to make the domes and other parts of the buildings so strong that they could last for a very long time.
Nowadays, some of these buildings still exist, and they are considered very important and special. People visit them to see their amazing beauty and to learn more about the history of architecture.