Alfons Maria Mucha, known internationally as Alphonse Mucha, was a Czech painter, illustrator and graphic artist, living in Paris during the Art Nouveau period, best known for his distinctly stylized and decorative theatrical posters, particularly those of Sarah Bernhardt. He produced illustrations, advertisements, decorative panels, and designs, which became among the best-known images of the period.
More beauty: https://artvee.com/artist/alphonse-mucha/
Went to the Mucha museum in Prague a few years back - it’s small, but theres some great pieces in there. Would definitely recommend it.