Bounding Box for 2d map

   **How to set bounding box value for 2d map over a particular country.**
    Actually I want to apply this on 2d map. In cesium there is a transition among 3d, 2d and Columbus views. In 3D my requirement was that in front of there should be India so I have change value of map center and it is working properly. Now in 2D my requirement

is that in front there should be only India as mentioned on website " "
(only the map portion). For this i have to use bounding box, I am trying but not getting success.

   Kindly put some focus on it. Thanks