A great cardigan does so much more than keep you cozy. The right one creates a polished, pulled-together silhouette while giving you a little extra coverage through the midsection — without awkward tugging, clinging or strategic posing. The key is in the details: structured shoulders, flattering necklines, strategic buttons and gently draped fabrics that turn a simple sweater into something tailored and sophisticated. We rounded up 17 Amazon cardigans that strike that sweet spot between comfy and polished, skimming the midsection rather than spotlighting it. From classic button-front styles an...