How to change window theme

Question

For going one another links like "home" "about us" etc when I m in home and I click on about us I go in another page without loading...

Answer 1

Its because all your files are in your local computer not hosted in a remote(different location) so there is no wait time("loading") needed.
Just read about http: and file: protocol.

Answer 2

But I copied image from Google and after close Google app all images are disappear..