body{font-family:sans-serif;margin:0;color:#222}header{display:flex;justify-content:space-between;padding:16px 32px;background:#f4f6f8}nav a{margin-left:16px;color:#246}main{max-width:720px;margin:40px auto;padding:0 16px}.btn{display:inline-block;padding:10px 20px;background:#246;color:#fff;border-radius:6px;text-decoration:none}footer{text-align:center;color:#888;padding:32px}