The grand manner style was based on what kind of art?

Classical art

Explanation:

    Grand Manner is an English term widely used from the 18th century to describe what was considered the highest style of art in academic theory - a style based on an idealized and classical approach.

   The term grand manners was given by Sir Joshua Reynolds and was discussed extensively in his speeches on art - fifteen lectures given to Royal Academy students between 1769 and 1790. Reynolds argued that painters should not copy nature slavishly but seek a form. widespread and ideal. This gives what is called great style to invention, composition, expression and even coloring and drapery “(Fourth discourse). In practice, it meant drawing the style of ancient Greek and Roman (classical) art and Italian Renaissance masters such as Raphael.