html{font-family:Arial,Helvetica,sans-serif;color:#1d1d1f;background:#fff}body{margin:0}header,nav,main,footer{max-width:860px;margin:auto;padding:24px}header{border-bottom:1px solid #ddd;font-size:28px;font-weight:800}nav{display:flex;flex-wrap:wrap;gap:16px;font-size:14px}a{color:#0067c9}header a{text-decoration:none}main{line-height:1.65}h1{font-size:28px;line-height:1.25}h2{font-size:22px;margin-top:36px}h3{font-size:18px;margin-top:28px}p,li{font-size:16px}code{white-space:normal;font-size:14px;background:#f1f6fa;padding:3px}footer{border-top:1px solid #ddd;color:#555;font-size:13px}@media(max-width:600px){header,nav,main,footer{padding:20px}h1{font-size:24px}h2{font-size:20px}}