System
Art Nouveau is a rebellion against the industrialization of art. The identity is defined by a total rejection of the straight line in favor of the "whiplash" curve, reflecting the vitality of nature.
What breaks it: Straight lines, right angles, or mechanical symmetry. Any hint of a grid or an industrial aesthetic destroys the organic unity of the style.
Applications: Luxury cosmetics, boutique hotel branding, and art nouveau posters.