body { font-family: Arial, sans-serif; line-height: 1.6; color: #333; max-width: 800px; margin: 0 auto; padding: 20px; } h1, h2, h3 { color: #1a1a1a; } img { max-width: 100%; height: auto; } .center { text-align: center; } .toc { background-color: #f9f9f9; padding: 20px; border: 1px solid #ddd; marg…