A large exhibition of works by the Art Nouveau artist Alfons Mucha is being extended in Prague until December 31, giving visitors more time to see around 230 works from the Mucha family’s collection, curators say. The show traces the life of the painter, poster artist and amateur photographer, who was one of the defining figures of the Belle époque period. “We have tried to retell Mucha’s life story as a Czech person, as a European and as a citizen of the world,” his great-grandson Marcus Mucha said during a recent guided tour. According to family legend, Alfons Mucha (1860-1939) was able to d…