In the 1980s, how was the louvre museum expanded by american architect i. m. pei

The Louvre is the world's largest and most recognizable museum in the world, as well as the historic monument in Paris. The task of expanding it was not easy but I. M. Pei did it masterfully with the creation of a central entryway which served as an visitor's center located underground and was covered by a glass pyramid.

The natural habitat around them