What is the author's style in Don't Look Now by Daphne du Maurier?

Du Maurier has John and Laura use humor and sarcasm to break the tension of the atmosphere around them, heavy with the memory of their dead daughter. The story opens with the two joking about a pair of sisters sitting at another table in the restaurant. They imagine that the sisters are cross-dressers, which causes Laura to laugh almost hysterically. John has succeeded in distracting her thoughts from their dead child, and "her voice, for the first time since they had come away, took on the old bubbling quality he loved." He continues thinking about the need for humor and jokes, adding, "if we can pick up the familiar routine of jokes shared at holiday and at home . . . then everything will fall into place."