What's so special about all we imagine as light?

Watched it today and wondering what is so great about this movie. This is a genuine question - I am not good with the technical aspects so that could be something I cant say was good/bad/extraordinary, etc. But the story did' seem so great to me. So request your help/views on what makes this great . If you disagree and want to downvote, can you comment the reason you disagree - which could be what I failed to capture or comprehend.