:root {
            --purple: #6366F1;
            --purple-deep: #4F46E5;
            --cyan: #06B6D4;
            --amber: #F59E0B;
            --ink: #0F172A;
            --stone: #475569;
            --snow: #F8FAFC;
            --white: #FFFFFF;
            --border: rgba(0,0,0,0.05);
            --shadow: 0 16px 32px -10px rgba(0,0,0,0.06);
            --shadow-lg: 0 22px 44px -14px rgba(0,0,0,0.10);
            --radius: 18px;
            --radius-sm: 12px;
            --font-mono: 'SF Mono','Fira Code','Cascadia Code',monospace;
        }
        *{box-sizing:border-box;margin:0;padding:0}
        body{
            font-family:-apple-system,BlinkMacSystemFont,"SF Pro Display","PingFang SC","Microsoft YaHei","Helvetica Neue",Arial,sans-serif;
            color:var(--ink);background:var(--snow);
            -webkit-font-smoothing:antialiased;line-height:1.55;overflow-x:hidden;
        }
        .glow{position:fixed;pointer-events:none;z-index:-1;border-radius:50%;filter:blur(120px);opacity:0.5}
        .glow--top{top:-280px;right:-180px;width:650px;height:650px;background:rgba(99,102,241,0.07)}
        .glow--bottom{bottom:-240px;left:-160px;width:600px;height:600px;background:rgba(6,182,212,0.06)}

        header{position:sticky;top:0;z-index:100;background:rgba(248,250,252,0.82);backdrop-filter:blur(22px);-webkit-backdrop-filter:blur(22px);border-bottom:1px solid var(--border)}
        .nav-wrap{max-width:1200px;margin:0 auto;padding:0 24px;height:68px;display:flex;align-items:center;justify-content:space-between;gap:16px}
        .logo{display:flex;align-items:center;gap:9px;text-decoration:none;font-weight:800;font-size:19px;color:var(--ink);white-space:nowrap;letter-spacing:-0.03em}
        .logo img{width:32px;height:32px;border-radius:7px;flex-shrink:0}
        .nav-links{display:flex;align-items:center;gap:6px;flex-wrap:wrap}
        .nav-links a{text-decoration:none;font-size:13.5px;font-weight:600;color:#475569;padding:7px 13px;border-radius:20px;transition:all 0.2s;white-space:nowrap}
        .nav-links a:hover,.nav-links a.active{color:var(--ink);background:rgba(99,102,241,0.06)}
        .nav-links a.btn-gh{background:var(--ink);color:#fff;padding:9px 19px;border-radius:24px;font-size:13px;margin-left:6px}
        .nav-links a.btn-gh:hover{background:#1E293B;transform:scale(1.04)}
        .nav-links a.airport-link{color:#F59E0B;font-weight:700}

        .section{max-width:1200px;margin:0 auto;padding:0 24px}
        .section-header{text-align:center;margin:64px auto 36px;max-width:640px}
        .chip{display:inline-block;font-size:11px;font-weight:700;text-transform:uppercase;letter-spacing:0.09em;padding:5px 15px;border-radius:20px;margin-bottom:10px}
        .chip--purple{color:#6366F1;background:rgba(99,102,241,0.07)}
        .chip--amber{color:#F59E0B;background:rgba(245,158,11,0.08)}
        .chip--cyan{color:#06B6D4;background:rgba(6,182,212,0.07)}
        .section-header h2{font-size:34px;font-weight:900;letter-spacing:-0.03em;line-height:1.2}
        .section-header h2 span{background:linear-gradient(135deg,#6366F1,#06B6D4);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}
        .section-header .sub{font-size:14.5px;color:#64748B;margin-top:6px}

        .hero-guide{text-align:center;padding:56px 24px 16px;max-width:900px;margin:0 auto}
        .hero-guide h1{font-size:48px;font-weight:900;letter-spacing:-0.04em;line-height:1.15;margin-bottom:14px}
        .hero-guide h1 span{background:linear-gradient(135deg,#6366F1,#06B6D4);-webkit-background-clip:text;-webkit-text-fill-color:transparent;background-clip:text}
        .hero-guide .tagline{font-size:17px;color:#475569;max-width:620px;margin:0 auto 24px}

        .btn{display:inline-flex;align-items:center;gap:8px;text-decoration:none;font-weight:600;font-size:15px;padding:14px 30px;border-radius:13px;transition:all 0.25s;cursor:pointer;border:none}
        .btn--primary{background:var(--purple);color:#fff;box-shadow:0 10px 22px -5px rgba(99,102,241,0.35)}
        .btn--primary:hover{background:var(--purple-deep);transform:translateY(-2px);box-shadow:0 16px 30px -7px rgba(99,102,241,0.45)}
        .btn--outline{background:#fff;color:var(--ink);border:1px solid #e2e8f0}
        .btn--outline:hover{background:#f1f5f9;border-color:#cbd5e1;transform:translateY(-2px)}

        .grid-3{display:grid;grid-template-columns:repeat(3,1fr);gap:18px;margin:0 auto 56px}
        .grid-2{display:grid;grid-template-columns:1fr 1fr;gap:20px;margin:0 auto 56px}
        .card{background:#fff;border-radius:var(--radius);padding:24px 20px;border:1px solid var(--border);transition:all 0.3s}
        .card:hover{transform:translateY(-4px);box-shadow:var(--shadow-lg);border-color:rgba(99,102,241,0.18)}
        .card .icon{font-size:34px;margin-bottom:8px}
        .card h3{font-size:18px;font-weight:800;margin-bottom:6px;letter-spacing:-0.02em}
        .card .desc{font-size:13.5px;color:#475569;line-height:1.55}
        .card .code-snip{margin-top:12px;background:#F1F5F9;border-radius:8px;padding:10px 14px;font-family:var(--font-mono);font-size:11.5px;color:#334155;border-left:3px solid var(--cyan);line-height:1.4}
        .tag{display:inline-block;margin-top:10px;font-size:10.5px;font-weight:700;text-transform:uppercase;letter-spacing:0.05em;padding:3px 11px;border-radius:10px}
        .tag--purple{color:#6366F1;background:rgba(99,102,241,0.07)}
        .tag--amber{color:#F59E0B;background:rgba(245,158,11,0.08)}
        .tag--cyan{color:#06B6D4;background:rgba(6,182,212,0.07)}

        .timeline{position:relative;max-width:700px;margin:0 auto 48px;padding-left:32px;border-left:2px dashed rgba(99,102,241,0.3)}
        .timeline-item{margin-bottom:28px;position:relative}
        .timeline-item::before{content:'🐾';position:absolute;left:-37px;top:2px;font-size:20px;background:var(--snow);border-radius:50%;padding:2px}
        .timeline-item h4{font-size:17px;font-weight:800;margin-bottom:4px;display:flex;align-items:center;gap:8px}
        .timeline-item .desc{font-size:13.5px;color:#475569;line-height:1.5}
        .timeline-item .code-snip{display:inline-block;margin-top:6px;background:#F1F5F9;padding:4px 10px;border-radius:6px;font-family:var(--font-mono);font-size:11px;color:#0F172A}

        .rule-table{width:100%;border-collapse:collapse;background:#fff;border-radius:var(--radius-sm);overflow:hidden;box-shadow:0 4px 12px rgba(0,0,0,0.03)}
        .rule-table th{background:#F8FAFC;font-weight:800;font-size:12px;text-transform:uppercase;letter-spacing:0.05em;color:#64748B;padding:14px 16px;text-align:left}
        .rule-table td{padding:12px 16px;border-bottom:1px solid var(--border);font-size:13.5px;color:var(--ink)}
        .rule-table code{background:#EEF2FF;padding:2px 8px;border-radius:4px;font-family:var(--font-mono);font-size:11px;color:#6366F1}

        .faq-item{background:#fff;border-radius:var(--radius-sm);padding:18px 20px;margin-bottom:10px;border:1px solid var(--border);transition:0.2s}
        .faq-item:hover{border-color:rgba(99,102,241,0.2)}
        .faq-item summary{font-weight:700;font-size:15px;cursor:pointer;list-style:none;display:flex;justify-content:space-between;align-items:center}
        .faq-item summary::after{content:'▼';font-size:12px;color:#94A3B8;transition:0.2s}
        .faq-item[open] summary::after{transform:rotate(180deg)}
        .faq-item p{font-size:13.5px;color:#475569;margin-top:8px;line-height:1.5}

        footer{background:#fff;border-top:1px solid var(--border);padding:48px 0 32px;margin-top:40px}
        .footer-wrap{max-width:1200px;margin:0 auto;padding:0 24px;display:flex;justify-content:space-between;gap:40px;flex-wrap:wrap}
        .footer-brand h4{font-size:16px;font-weight:800;margin-bottom:8px}
        .footer-brand p{font-size:13px;color:#64748B;max-width:280px;line-height:1.55}
        .footer-links{display:flex;gap:50px}
        .footer-links h5{font-size:12px;font-weight:700;text-transform:uppercase;letter-spacing:0.06em;margin-bottom:14px}
        .footer-links ul{list-style:none}
        .footer-links li{margin-bottom:8px}
        .footer-links a{text-decoration:none;font-size:13px;color:#64748B;transition:color 0.2s}
        .footer-links a:hover{color:var(--ink)}
        .note-sm{font-size:12.5px;color:#94A3B8;margin-top:8px}

        @media(max-width:1024px){.grid-3,.grid-2{grid-template-columns:1fr}.hero-guide h1{font-size:36px}}
        @media(max-width:768px){
            .nav-wrap{flex-wrap:wrap;height:auto;padding:12px 16px;gap:10px;justify-content:center}
            .nav-links{justify-content:center;gap:2px}
            .nav-links a{font-size:12px;padding:5px 10px}
            .hero-guide h1{font-size:28px}
            .timeline{padding-left:24px}
            .footer-wrap{flex-direction:column}
            .footer-links{gap:30px;flex-wrap:wrap}
        }