No doubts, beautiful is not exactly the fair term for define it . But it is an useful one. Seductive for atmosphere , for acting, for summer air and for the gentle respiration of details.
A lovely story, with all precious flavors of vacantion, about a young woman, a young man, a girl, a house and small pieces with taste of Swiming pool, maybe, in some measure, Le Grand Meaulnes.
The basic virtue - you feel it as a personal story, as a water in which you swim . Small details, dialogues, exercises of seduction and seductive cinematography.
In short, just delightful, pleasant and full of sparkles of a lost time.