:root {
            --bg-main: #f8fafc;
            --bg-card: #ffffff;
            --primary: #6366f1;
            --primary-dark: #4f46e5;
            --accent: #06b6d4;
            --text-heading: #0f172a;
            --text-body: #475569;
            --text-muted: #94a3b8;
            --border: #e2e8f0;
            --shadow-sm: 0 1px 3px rgba(0,0,0,0.05);
            --shadow-md: 0 10px 25px rgba(0,0,0,0.06);
            --shadow-lg: 0 20px 40px rgba(0,0,0,0.08);
            --radius-sm: 10px;
            --radius-md: 16px;
            --transition: 0.25s ease;
        }

        * { box-sizing: border-box; margin: 0; padding: 0; }
        body {
            font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Noto Sans SC", sans-serif;
            background-color: var(--bg-main);
            color: var(--text-body);
            line-height: 1.6;
            overflow-x: hidden;
        }
        a { color: inherit; text-decoration: none; }

        /* 导航栏 */
        .header {
            position: fixed; top: 0; left: 0; width: 100%; z-index: 1000;
            background: rgba(255,255,255,0.85); backdrop-filter: blur(16px);
            border-bottom: 1px solid var(--border);
        }
        .nav-container {
            max-width: 1280px; margin: 0 auto; padding: 1rem 2rem;
            display: flex; justify-content: space-between; align-items: center;
        }
        .logo {
            display: flex; align-items: center; gap: 10px;
            font-size: 1.4rem; font-weight: 800; color: var(--text-heading);
        }
        .logo-svg { width: 32px; height: 32px; flex-shrink: 0; }
        .logo-badge {
            background: linear-gradient(135deg, var(--primary), var(--accent));
            color: white; font-size: 0.75rem; padding: 2px 8px; border-radius: 20px; font-weight: 600;
        }
        .nav-menu { display: flex; align-items: center; gap: 2.2rem; }
        .nav-link {
            font-size: 0.93rem; font-weight: 600; color: var(--text-body);
            transition: color 0.2s; position: relative; padding: 4px 0;
        }
        .nav-link::after {
            content: ''; position: absolute; bottom: -2px; left: 0;
            width: 0; height: 2px; background: var(--primary); border-radius: 2px;
            transition: width var(--transition);
        }
        .nav-link:hover, .nav-link.active { color: var(--primary); }
        .nav-link:hover::after, .nav-link.active::after { width: 100%; }
        .btn-nav {
            background: var(--text-heading); color: #ffffff !important;
            padding: 8px 18px; border-radius: 8px; font-size: 0.9rem; font-weight: 600;
            transition: all var(--transition);
        }
        .btn-nav:hover {
            background: var(--primary);
            box-shadow: 0 4px 12px rgba(99,102,241,0.35);
            transform: translateY(-1px);
        }

        /* 页面头部 */
        .page-hero {
            padding: 150px 2rem 40px 2rem;
            text-align: center;
            max-width: 800px;
            margin: 0 auto;
        }
        .page-hero .hero-eyebrow {
            display: inline-block;
            background: #eef2ff;
            color: var(--primary);
            font-size: 0.85rem;
            font-weight: 700;
            padding: 5px 16px;
            border-radius: 30px;
            margin-bottom: 1rem;
            letter-spacing: 0.03em;
        }
        .page-hero h1 {
            font-size: 2.8rem;
            font-weight: 900;
            color: var(--text-heading);
            margin-bottom: 1rem;
            letter-spacing: -0.02em;
        }
        .page-hero h1 span {
            background: linear-gradient(135deg, var(--primary), var(--accent));
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
        }
        .page-hero p {
            font-size: 1.1rem;
            color: var(--text-body);
        }

        /* 内容布局 */
        .guide-container {
            max-width: 1280px;
            margin: 0 auto;
            padding: 0 2rem 80px 2rem;
            display: grid;
            grid-template-columns: 280px 1fr;
            gap: 3rem;
        }
        .guide-sidebar {
            position: sticky;
            top: 100px;
            height: fit-content;
            background: white;
            border: 1px solid var(--border);
            border-radius: var(--radius-md);
            padding: 1.5rem;
            box-shadow: var(--shadow-sm);
        }
        .sidebar-title {
            font-size: 1.1rem;
            font-weight: 700;
            color: var(--text-heading);
            margin-bottom: 1rem;
            padding-bottom: 0.8rem;
            border-bottom: 1px solid var(--border);
        }
        .sidebar-nav { list-style: none; }
        .sidebar-nav li { margin-bottom: 0.5rem; }
        .sidebar-nav a {
            display: block;
            padding: 8px 12px;
            border-radius: 8px;
            font-weight: 600;
            font-size: 0.92rem;
            color: var(--text-body);
            transition: all 0.2s;
        }
        .sidebar-nav a:hover, .sidebar-nav a.active {
            background: rgba(99,102,241,0.08);
            color: var(--primary);
        }

        .guide-content {
            display: flex;
            flex-direction: column;
            gap: 2.5rem;
        }

        .guide-card {
            background: white;
            border: 1px solid var(--border);
            border-radius: var(--radius-md);
            padding: 2.5rem;
            box-shadow: var(--shadow-sm);
            transition: box-shadow var(--transition);
        }
        .guide-card:hover { box-shadow: var(--shadow-md); }
        .guide-card h2 {
            font-size: 1.8rem;
            color: var(--text-heading);
            font-weight: 800;
            margin-bottom: 1.5rem;
            display: flex;
            align-items: center;
            gap: 12px;
        }

        .step-list { list-style: none; counter-reset: step-counter; }
        .step-item {
            position: relative;
            padding-left: 3.5rem;
            margin-bottom: 2rem;
        }
        .step-item:last-child { margin-bottom: 0; }
        .step-item::before {
            counter-increment: step-counter;
            content: counter(step-counter);
            position: absolute;
            left: 0; top: 0;
            width: 2.4rem; height: 2.4rem;
            background: linear-gradient(135deg, var(--primary), var(--primary-dark));
            color: white;
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            font-weight: 700;
            font-size: 1.1rem;
            box-shadow: 0 4px 10px rgba(99,102,241,0.3);
        }
        .step-item h3 {
            font-size: 1.2rem;
            color: var(--text-heading);
            font-weight: 700;
            margin-bottom: 0.5rem;
        }
        .step-item p {
            font-size: 1rem;
            color: var(--text-body);
            line-height: 1.6;
        }
        .notice-box {
            background: #f1f5f9;
            border-left: 4px solid var(--primary);
            padding: 1rem 1.2rem;
            border-radius: 0 8px 8px 0;
            margin-top: 1rem;
            font-size: 0.9rem;
            color: #334155;
        }

        .faq-section {
            background: white;
            border: 1px solid var(--border);
            border-radius: var(--radius-md);
            padding: 2.5rem;
        }
        .faq-section h2 {
            font-size: 1.8rem;
            color: var(--text-heading);
            font-weight: 800;
            margin-bottom: 1.5rem;
        }
        .faq-grid {
            display: grid;
            grid-template-columns: repeat(2, 1fr);
            gap: 1.5rem;
        }
        .faq-item {
            background: var(--bg-main);
            border-radius: var(--radius-sm);
            padding: 1.4rem;
            border: 1px solid var(--border);
        }
        .faq-item h4 {
            font-size: 1.05rem;
            color: var(--text-heading);
            font-weight: 700;
            margin-bottom: 0.5rem;
        }
        .faq-item p {
            font-size: 0.9rem;
            color: var(--text-body);
            line-height: 1.6;
        }

        /* Footer */
        .footer {
            background-color: #ffffff;
            border-top: 1px solid var(--border);
            padding: 60px 2rem 30px 2rem;
            font-size: 0.9rem;
            color: var(--text-body);
        }
        .footer-container {
            max-width: 1280px; margin: 0 auto;
            display: flex; justify-content: space-between;
            gap: 2rem; flex-wrap: wrap;
        }
        .footer-brand { max-width: 360px; }
        .footer-brand h4 {
            font-size: 1.2rem; color: var(--text-heading);
            margin-bottom: 1rem;
        }
        .footer-links h5 {
            color: var(--text-heading);
            font-size: 0.95rem; margin-bottom: 1rem;
        }
        .footer-links ul { list-style: none; }
        .footer-links li { margin-bottom: 0.5rem; }
        .footer-bottom {
            max-width: 1280px; margin: 40px auto 0 auto;
            padding-top: 20px; border-top: 1px solid var(--border);
            text-align: center; font-size: 0.85rem; color: #94a3b8;
        }

        @media (max-width: 968px) {
            .guide-container { grid-template-columns: 1fr; }
            .guide-sidebar { position: static; }
            .nav-menu { display: none; }
            .faq-grid { grid-template-columns: 1fr; }
        }