How is 'Children Of Men' considered post-modern?

Post-modernism is considered to be a group of ideologies and theories that try to define the state of affairs in society through art, literature and the media. The movement can be self-reflexive and it can include a focus of low culture as art, which was revolutionary at the time. Children Of Men could be considered as post-modern because it borrows or appropriates from a range of different genres such as action, road movie, science fiction and many more. Another genre this film could be linked to is documentary because there aren’t many cuts throughout the duration of the film, which is also linked to cinematography. We could also say that it’s a sci-fi film because they show new pieces of technology however it is not a conventional sci-fi film because it doesn't utilise its typical conventions for example the clothing of the characters and it is realistic in terms of the setting and the fact that it could actually happen. Also, the film is based around a threat to humanity and infertility however beyond this point this isn’t really typical of sci-fi at all. A useful way to think about genre is to think about repetition and variation and this film uses this as it repeats the fact that its set in the future and the variable element is that it is quite realistic. 
Another reason why Children Of Men can be considered as post-modern is because there are many intertextual references, which argues with the culture and it challenges the distinction between high culture and popular culture, by deliberately contrasting graffiti, art and music. Some of the intertextual references used in this film are the Pink Floyd pig, which relates to ‘Animal Farm’ and the Battersby Power station, Opera, Banksy and Picasso. In this post-modern era, we live in a world where we are enclosed by all forms of media where different mediums make references to other mediums. The film is suggesting that all art is considered to be of equal value and it argues that popular culture such as graffiti produced by Banksy of the two policemen kissing and pop music is equally as valid and important as high culture such as the opera and Picasso’s famous painting of the Guernica. The first piece of art that we witness in the film produced by Banksy is typical of his ironic representations of unfair observation society that has raised the status of graffiti. We witness the Picasso painting of the Guernica in Theo’s friend’s dining room. This painting expresses horror linked to the Nazi bombing of civilians in Guernica, Spain.