It’s hard to tell because she doesn’t show much towards Kazuya and she blushes from time to time but that’s it. It’s pretty obvious Kazuya likes her but not the same vice versa.
Hard to answer this question without revealing spoilers from the manga, as the manga is much further ahead than the anime, so click below at your own risk.
Starting from chapter 164, the author made Chizuru's feelings very clear to the readers. She does in fact have feelings for Kazuya, and currently in the process of realizing them (chapter 182 as of this moment). Often time, when they are alone together, Chizuru would get overly conscious of her feelings, resulting in her getting flustered and blushed quite frequently around Kazuya.