Elegance is the key
Elegance is a synonym for beauty that has come to acquire the additional connotations of unusual effectiveness and simplicity. It is frequently used as a standard of tastefulness particularly in the areas of visual design, decoration, the sciences, and the aesthetics of mathematics. Elegant things exhibit refined grace and dignified propriety.
Essential components of the concept include simplicity and consistency of design, focusing on the essential features of an object. In art of any kind one might also require dignified grace, or restrained beauty of style.
Visual stimuli are frequently considered elegant if a small number of colors and stimuli are used, emphasizing the remainder.
Source: https://en.wikipedia.org/wiki/Elegance