body { font-family: 'Hiragino Kaku Gothic Pro', 'メイリオ', sans-serif; max-width: 800px; margin: 0 auto; padding: 20px; line-height: 1.8; color: #2d3748; background-color: #f8fafc; } .intro { font-size: 17px; background: linear-gradient(to right, #e6f3ff, #ffffff); padding: 25px; border-radius: 12px; b…