Minecraft Sky block

Hi. So I'm creating a map with a kinda of "Truman show" like structure in it, i.e. a dome structure in which a town is built inside. But the dome structure is suppose to mimic the actual sky. I don't really have any moding experience so I was wondering if it is possible to mod a block so that it reflects the actual sky above it? Or is there a way to use a texture pack to imitate the same thing? Any suggestions or ideas?

Thanks