What is the author's style in Sarah's Key by Tatiana de Rosnay?

Sarah's Key by Tatiana de Rosnay is a work of fiction about a young girl, Sarah Starzynski, who was collected in France during the roundup of Jews in July 16, 1942, when the French police arrested thousands of Jews throughout Paris. The girl and her family were sent to an internment camp where people were held before being sent to Auschwitz where they were executed.