You need a hat today, don’t you? I know I do. This one, looking like a very chic chartreuse butterfly landed on its wearer’s head, appears in “The Gilded Age,” the new HBO series created by Julian Fellowes (“Downton Abbey”) and set in 1880s New York. Pictured here are Kelli O’Hara, Louisa Jacobson and rather a lot of floral decorations; I love how the hat looks like it’s winking at us. So far I’ve watched one episode of the show, and it’s basically Downton Lite: lots of sweeping gowns, old money, strivers, lip-pursing (Christine Baranski, as an dignified New York dowager, is a pro at this), and arch pronouncements in grand drawing rooms. The costumes, designed by Kasia Walicka-Maimone, feel a bit understated so far, but we’ve got nine episodes to go and I’m hoping for some full “The Age of Innocence” elegance. “The Gilded Age” streams on HBO Max; new episodes appear on Mondays.