Modernism is a type of literature that is marked by its intentional break with tradition. It grew out of the mass of destruction and disillusionment that was left in the wake of World War I. This war was one of the most brutal in history. Authors of the time saw what was happening, noted the traditional sources of power that got society to the point of a world war, and wanted to break away from those sources of power. This happened in religious, political, and social settings. The "hostility towards civilization" that you reference in your prompt can be seen as a direct result of the horrors suffered on all sides during World War I. Modernist authors wrote to show these horrors, tie them to civilization, and show why tradition must be broken.
Modernist writing places the focus on subjective perception rather than objective truth and relies heavily on individualism. This can be seen in the works of modernist authors like Virginia Woolf and James Joyce, who wrote in a stream-of-consciousness style to elucidate the inner workings of the mind. This style brings the focus away from traditional sorts of power and towards how the individual sees the world.
If you'd like to get a sense of this hostility towards civilization yourself, there are a variety of modernist authors who you could read. Some of the most famous who adhere to the modernist writing style include Ezra Pound, Gertrude Stein, and T. S. Eliot.