It is a French phrase often used in art and design to indicate a specific style or influence.
For example:
* "This painting is au gres de Van Gogh." (This painting is in the style of Van Gogh.)
* "The architecture of this building is au gres of the Renaissance." (The architecture of this building is in the style of the Renaissance.)
It's important to note that "au gres" is often used in a broader sense, not just for specific artists or periods. It can also refer to a general style or aesthetic.