body { font-family: "Yu Gothic", "Hiragino Kaku Gothic Pro", Meiryo, sans-serif; line-height: 1.6; margin: 0; padding: 0; background−color: #f9f9f9; color: #333; } main { max-width: 800px; margin: 2rem auto; background: #fff; padding: 2rem; box-shadow: 0 0 8px rgba(0,0,0,0.1); } h1, h2, h3 { color: …