The sun was blazing, the dog was panting, and Amanda Seyfried wanted to get something off her chest: “I cut my own bangs,” she said, almost apologetically, of her long, sideswept layers. “But they look good, right?” We were in Stone Ridge, New York, at a private estate to photograph the actress for her third Allure cover. “They’re good,” said hairstylist Rutger, then added gently, “but I’m going to need to even them out a bit.” While in the makeup chair, Seyfried tossed blueberries into the air to Finn, her Australian shepherd (and Instagram costar). It was lively on set that day, and Seyfried was in the mood to confess things. “I hate it,” she said of her Pure Barre workout. “But it has moved my butt—it’s higher now.” Layers…