It is no secret that Mauritshuis holds monumental works from the Dutch Golden Age. Up until recently, the museum was frequented by eager tourists from all over the world. Now, its doors shuttered, it offers online closeups of selected treasures, including Vermeer’s paintings in Delft and works by Rubens and Rembrandt. It’s an enlightening guide to the intricacies of Dutch culture. Included are Renaissance, Baroque, and Early Netherlandish paintings. —E.C.