body { background: #e6e7e8; /* 曇り空のような淡いグレー */ font-family: "Hiragino Kaku Gothic ProN", Meiryo, sans-serif; color: #222; line-height: 1.9; padding: 3em 1em; } .container { max-width: 720px; background: #ffffff; padding: 2.5em; margin: auto; box-shadow: 0 0 15px rgba(0,0,0,0.05); border-radius: 10px…