:root {
            --primary: #2563eb;
            --accent: #06b6d4;
            --bg: #f8fafc;
            --text: #0f172a;
            --border: #e2e8f0;
            --shadow-sm: 0 2px 8px rgba(15, 23, 42, 0.04);
            --shadow-md: 0 8px 20px rgba(15, 23, 42, 0.08);
            --radius: 8px;
        }
        body {
            background-color: var(--bg);
            color: var(--text);
            font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
            line-height: 1.6;
            background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.8' numOctaves='2' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)' opacity='0.03'/%3E%3C/svg%3E");
            background-attachment: fixed;
        }
        h1, h2, h3, .brand-font {
            font-family: 'Inter', 'Segoe UI', system-ui, sans-serif;
            font-weight: 800;
            letter-spacing: -0.02em;
        }
        .navbar {
            background: rgba(255,255,255,0.85);
            backdrop-filter: blur(10px);
            border-bottom: 1px solid var(--border);
            padding: 0.75rem 1.5rem;
            box-shadow: var(--shadow-sm);
        }
        .navbar-brand {
            font-weight: 900;
            font-size: 1.8rem;
            color: var(--primary);
            letter-spacing: -0.03em;
            display: flex;
            align-items: center;
            gap: 0.4rem;
        }
        .navbar-brand i {
            color: var(--accent);
            font-size: 1.6rem;
        }
        .nav-link {
            font-weight: 600;
            color: var(--text);
            margin-left: 1.2rem;
            transition: color 0.2s;
            border-radius: 4px;
        }
        .nav-link:hover {
            color: var(--primary);
        }
        .layout-wrapper {
            display: flex;
            max-width: 1440px;
            margin: 2rem auto;
            gap: 2rem;
            padding: 0 1.5rem;
        }
        .sidebar {
            width: 230px;
            flex-shrink: 0;
            position: sticky;
            top: 100px;
            height: fit-content;
            background: white;
            border: 1px solid var(--border);
            border-radius: var(--radius);
            padding: 1.2rem 0.8rem;
            box-shadow: var(--shadow-sm);
        }
        .sidebar-item {
            display: flex;
            align-items: center;
            gap: 0.7rem;
            padding: 0.7rem 0.8rem;
            border-radius: 6px;
            color: var(--text);
            text-decoration: none;
            font-weight: 500;
            transition: all 0.15s;
        }
        .sidebar-item i {
            width: 20px;
            color: var(--primary);
        }
        .sidebar-item:hover {
            background: #eff6ff;
            color: var(--primary);
            transform: translateX(4px);
        }
        .main-content {
            flex: 1;
            min-width: 0;
        }
        .hero-section {
            position: relative;
            background: linear-gradient(135deg, #0b1e4b 0%, #1e3a8a 100%);
            border-radius: var(--radius);
            padding: 5rem 3rem;
            margin-bottom: 3rem;
            overflow: hidden;
            box-shadow: var(--shadow-md);
            color: white;
            background-image: url("data:image/svg+xml,%3Csvg width='100' height='100' viewBox='0 0 100 100' xmlns='http://www.w3.org/2000/svg'%3E%3Cpath d='M25 25 L35 25 L30 15 Z' fill='%23ffffff' opacity='0.05'/%3E%3Ccircle cx='70' cy='40' r='4' fill='%2306b6d4' opacity='0.2'/%3E%3C/svg%3E"), linear-gradient(135deg, #0b1e4b 0%, #1e3a8a 100%);
            background-blend-mode: overlay;
            border: 1px solid rgba(255,255,255,0.1);
        }
        .hero-section::after {
            content: "";
            position: absolute;
            inset: 0;
            background: radial-gradient(circle at 80% 20%, rgba(6,182,212,0.2), transparent 40%);
            pointer-events: none;
        }
        .hero-content {
            position: relative;
            z-index: 2;
            max-width: 700px;
        }
        .hero-content h1 {
            font-size: 3.2rem;
            font-weight: 900;
            margin-bottom: 1rem;
            line-height: 1.1;
        }
        .hero-sub {
            font-size: 1.25rem;
            opacity: 0.85;
            margin-bottom: 2rem;
        }
        .btn-hero {
            background: var(--accent);
            border: none;
            padding: 0.8rem 2rem;
            border-radius: 30px;
            font-weight: 700;
            color: #fff;
            transition: 0.2s;
        }
        .btn-hero:hover {
            background: #0e9bb0;
            transform: translateY(-2px);
        }
        .card-grid {
            display: grid;
            grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
            gap: 1.5rem;
            margin-bottom: 3rem;
        }
        .card-item {
            background: white;
            border: 1px solid var(--border);
            border-radius: var(--radius);
            overflow: hidden;
            transition: transform 0.25s ease, box-shadow 0.25s ease;
            box-shadow: var(--shadow-sm);
            cursor: pointer;
        }
        .card-item:hover {
            transform: translateY(-6px);
            box-shadow: var(--shadow-md);
            border-color: #c7d2fe;
        }
        .card-cover {
            width: 100%;
            aspect-ratio: 3/4;
            background: linear-gradient(145deg, #dbeafe, #bae6fd);
            display: flex;
            align-items: center;
            justify-content: center;
            color: var(--primary);
            font-size: 2.5rem;
            border-bottom: 1px solid var(--border);
            background-image: url('{随机图片}');
            background-size: cover;
            background-position: center;
        }
        .card-cover i {
            background: rgba(255,255,255,0.7);
            padding: 1rem;
            border-radius: 50%;
        }
        .card-body {
            padding: 1rem;
        }
        .card-title {
            font-weight: 700;
            font-size: 1.1rem;
            margin-bottom: 0.25rem;
        }
        .card-tags {
            display: flex;
            gap: 0.4rem;
            flex-wrap: wrap;
        }
        .badge-soft {
            background: #e0f2fe;
            color: #0369a1;
            font-size: 0.7rem;
            padding: 0.3rem 0.6rem;
            border-radius: 20px;
        }
        .section-title {
            font-size: 2rem;
            font-weight: 800;
            margin: 2.5rem 0 1.5rem;
            border-left: 6px solid var(--primary);
            padding-left: 1rem;
        }
        .feature-card {
            background: white;
            border: 1px solid var(--border);
            border-radius: var(--radius);
            padding: 1.8rem 1.2rem;
            text-align: center;
            transition: all 0.2s;
            box-shadow: var(--shadow-sm);
        }
        .feature-card:hover {
            transform: translateY(-4px);
            box-shadow: var(--shadow-md);
        }
        .feature-icon {
            font-size: 2.5rem;
            color: var(--primary);
            margin-bottom: 1rem;
        }
        .steps-wrapper {
            display: flex;
            flex-direction: column;
            gap: 1.5rem;
        }
        .step-item {
            display: flex;
            align-items: flex-start;
            gap: 1.2rem;
            background: white;
            padding: 1.5rem;
            border-radius: var(--radius);
            border: 1px solid var(--border);
        }
        .step-num {
            background: var(--primary);
            color: white;
            width: 36px;
            height: 36px;
            border-radius: 20px;
            display: flex;
            align-items: center;
            justify-content: center;
            font-weight: 800;
            font-size: 1.2rem;
            flex-shrink: 0;
        }
        .faq-accordion .card {
            border: 1px solid var(--border);
            border-radius: var(--radius) !important;
            margin-bottom: 1rem;
        }
        .faq-accordion .btn-link {
            color: var(--text);
            font-weight: 700;
            font-size: 1.1rem;
            text-decoration: none;
        }
        .faq-accordion .btn-link i {
            color: var(--primary);
            margin-right: 0.5rem;
        }
        .cta-box {
            background: white;
            border: 2px solid var(--primary);
            border-radius: var(--radius);
            padding: 3rem;
            text-align: center;
            margin: 3rem 0;
            background-image: radial-gradient(circle at 10% 30%, rgba(6,182,212,0.08), transparent 50%);
        }
        .back-to-top {
            position: fixed;
            right: 25px;
            bottom: 25px;
            width: 46px;
            height: 46px;
            border-radius: 30px;
            background: var(--primary);
            color: white;
            border: none;
            box-shadow: var(--shadow-md);
            opacity: 0;
            transition: opacity 0.3s, transform 0.2s;
            transform: translateY(10px);
            z-index: 999;
        }
        .back-to-top.show {
            opacity: 1;
            transform: translateY(0);
        }
        footer {
            background: white;
            border-top: 1px solid var(--border);
            padding: 2rem 1.5rem;
            margin-top: 3rem;
            color: #475569;
        }
        .friend-links {
            background: white;
            border-radius: var(--radius);
            padding: 1.5rem;
            margin: 2rem 0;
            border: 1px solid var(--border);
        }
        .link-placeholder {
            color: var(--primary);
            font-weight: 500;
        }
        @media (max-width: 992px) {
            .layout-wrapper {
                flex-direction: column;
            }
            .sidebar {
                width: 100%;
                position: static;
                display: flex;
                flex-wrap: wrap;
                gap: 0.2rem;
            }
            .sidebar-item {
                width: auto;
            }
            .hero-content h1 {
                font-size: 2.5rem;
            }
        }

/* --- 子页面追加 --- */
/* 本页专属样式 —— 关于页 */
        .about-hero {
            background: linear-gradient(135deg, rgba(37, 99, 235, 0.06) 0%, rgba(6, 182, 212, 0.04) 100%);
            border-bottom: 1px solid var(--border);
            padding: 4rem 0 3rem;
            margin-bottom: 2rem;
        }
.about-hero h1 {
            font-weight: 800;
            color: var(--text);
            margin-bottom: 0.75rem;
            font-size: clamp(1.8rem, 4vw, 2.6rem);
            letter-spacing: -0.02em;
        }
.about-hero .lead {
            color: #475569;
            max-width: 720px;
            font-size: 1.1rem;
            line-height: 1.7;
        }
.about-meta-card {
            background: #ffffff;
            border: 1px solid var(--border);
            border-radius: var(--radius);
            padding: 1.5rem 1.75rem;
            box-shadow: var(--shadow-sm);
            margin-bottom: 2.5rem;
            display: flex;
            flex-wrap: wrap;
            gap: 1.5rem 3rem;
        }
.about-meta-card .meta-item {
            display: flex;
            align-items: center;
            gap: 0.6rem;
            font-size: 0.95rem;
            color: #334155;
        }
.about-meta-card .meta-item i {
            color: var(--primary);
            font-size: 1.1rem;
            width: 1.3rem;
            text-align: center;
        }
.about-section {
            padding: 1.5rem 0 2.5rem;
        }
.about-section h2 {
            font-weight: 700;
            font-size: 1.6rem;
            color: var(--text);
            margin-bottom: 1.2rem;
            letter-spacing: -0.01em;
            position: relative;
            padding-bottom: 0.6rem;
        }
.about-section h2::after {
            content: '';
            position: absolute;
            bottom: 0;
            left: 0;
            width: 48px;
            height: 3px;
            background: var(--primary);
            border-radius: 3px;
        }
.about-section p {
            color: #334155;
            line-height: 1.8;
            font-size: 1rem;
            margin-bottom: 1rem;
        }
.about-section ul {
            padding-left: 1.2rem;
            margin-bottom: 1.2rem;
        }
.about-section li {
            color: #334155;
            line-height: 1.8;
            margin-bottom: 0.4rem;
            position: relative;
        }
.about-section li::marker {
            color: var(--primary);
        }
.about-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
            gap: 1.5rem;
            margin: 1.5rem 0 2rem;
        }
.about-feature-box {
            background: #ffffff;
            border: 1px solid var(--border);
            border-radius: var(--radius);
            padding: 1.5rem 1.4rem;
            box-shadow: var(--shadow-sm);
            transition: transform 0.2s ease, box-shadow 0.2s ease;
        }
.about-feature-box:hover {
            transform: translateY(-3px);
            box-shadow: var(--shadow-md);
        }
.about-feature-box .icon-circle {
            width: 46px;
            height: 46px;
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            background: rgba(37, 99, 235, 0.08);
            color: var(--primary);
            font-size: 1.25rem;
            margin-bottom: 1rem;
        }
.about-feature-box h3 {
            font-size: 1.1rem;
            font-weight: 700;
            color: var(--text);
            margin-bottom: 0.6rem;
        }
.about-feature-box p {
            font-size: 0.92rem;
            color: #475569;
            line-height: 1.7;
            margin-bottom: 0;
        }
.stats-row {
            display: flex;
            flex-wrap: wrap;
            gap: 1.5rem;
            margin: 1.5rem 0;
        }
.stat-item {
            flex: 1;
            min-width: 160px;
            background: rgba(37, 99, 235, 0.04);
            border: 1px solid rgba(37, 99, 235, 0.12);
            border-radius: var(--radius);
            padding: 1.2rem 1.5rem;
            text-align: center;
        }
.stat-item .num {
            font-size: 1.8rem;
            font-weight: 800;
            color: var(--primary);
            line-height: 1.2;
        }
.stat-item .label {
            font-size: 0.88rem;
            color: #475569;
            margin-top: 0.3rem;
        }
.quote-box {
            background: rgba(6, 182, 212, 0.05);
            border-left: 4px solid var(--accent);
            padding: 1.2rem 1.5rem;
            border-radius: 0 var(--radius) var(--radius) 0;
            margin: 1.5rem 0;
            font-style: italic;
            color: #334155;
            line-height: 1.7;
        }
.timeline {
            margin: 1.5rem 0;
            position: relative;
            padding-left: 1.8rem;
        }
.timeline::before {
            content: '';
            position: absolute;
            left: 6px;
            top: 4px;
            bottom: 4px;
            width: 2px;
            background: rgba(37, 99, 235, 0.15);
        }
.timeline-item {
            position: relative;
            margin-bottom: 1.5rem;
        }
.timeline-item::before {
            content: '';
            position: absolute;
            left: -1.8rem;
            top: 6px;
            width: 12px;
            height: 12px;
            border-radius: 50%;
            background: var(--primary);
            border: 2px solid #ffffff;
            box-shadow: 0 0 0 2px rgba(37, 99, 235, 0.3);
        }
.timeline-item .year {
            font-weight: 700;
            color: var(--primary);
            font-size: 0.95rem;
            margin-bottom: 0.3rem;
        }
.timeline-item .desc {
            color: #334155;
            font-size: 0.95rem;
            line-height: 1.6;
        }
.about-hero {
                padding: 2.5rem 0 2rem;
            }
.about-meta-card {
                padding: 1.2rem 1.2rem;
                gap: 1rem;
            }
.stats-row {
                gap: 0.8rem;
            }
.stat-item {
                min-width: 120px;
                padding: 1rem;
            }
.stat-item .num {
                font-size: 1.4rem;
            }

/* --- 子页面追加 --- */
/* 本页专属样式 - 订阅页 */
        .subscribe-hero {
            background: linear-gradient(135deg, rgba(37, 99, 235, 0.08) 0%, rgba(6, 182, 212, 0.08) 100%);
            border-bottom: 1px solid var(--border);
            padding: 80px 0 60px;
        }
.subscribe-form-wrap {
            background: #ffffff;
            border-radius: var(--radius);
            box-shadow: var(--shadow-md);
            padding: 40px;
            border: 1px solid var(--border);
            max-width: 560px;
            margin: 0 auto;
        }
.subscribe-form-wrap .form-label {
            color: var(--text);
            font-weight: 600;
        }
.subscribe-form-wrap .form-control {
            border-radius: var(--radius);
            border-color: var(--border);
            padding: 12px 16px;
            font-size: 0.95rem;
        }
.subscribe-form-wrap .form-control:focus {
            border-color: var(--primary);
            box-shadow: 0 0 0 0.2rem rgba(37, 99, 235, 0.1);
        }
.subscribe-btn {
            background: var(--primary);
            color: #fff;
            border: none;
            padding: 12px 32px;
            border-radius: var(--radius);
            font-weight: 600;
            width: 100%;
            transition: all 0.3s ease;
        }
.subscribe-btn:hover {
            background: #1d4ed8;
            transform: translateY(-2px);
            box-shadow: 0 6px 16px rgba(37, 99, 235, 0.3);
        }
.benefit-card {
            background: #ffffff;
            border: 1px solid var(--border);
            border-radius: var(--radius);
            padding: 32px 24px;
            height: 100%;
            transition: all 0.3s ease;
            text-align: center;
        }
.benefit-card:hover {
            transform: translateY(-6px);
            box-shadow: var(--shadow-md);
            border-color: var(--primary);
        }
.benefit-icon {
            font-size: 2.2rem;
            color: var(--primary);
            margin-bottom: 16px;
        }
.benefit-card h3 {
            font-size: 1.1rem;
            font-weight: 700;
            color: var(--text);
            margin-bottom: 12px;
        }
.benefit-card p {
            font-size: 0.9rem;
            color: #64748b;
            line-height: 1.7;
        }
.plan-card {
            background: #ffffff;
            border: 2px solid var(--border);
            border-radius: var(--radius);
            padding: 32px 24px;
            text-align: center;
            transition: all 0.3s ease;
            height: 100%;
        }
.plan-card.featured {
            border-color: var(--primary);
            box-shadow: 0 8px 30px rgba(37, 99, 235, 0.12);
            position: relative;
        }
.plan-card.featured::before {
            content: "最受欢迎";
            position: absolute;
            top: -12px;
            left: 50%;
            transform: translateX(-50%);
            background: var(--primary);
            color: #fff;
            font-size: 0.75rem;
            font-weight: 600;
            padding: 4px 16px;
            border-radius: 20px;
            white-space: nowrap;
        }
.plan-card h3 {
            font-size: 1.2rem;
            font-weight: 700;
            color: var(--text);
            margin-bottom: 16px;
        }
.plan-price {
            font-size: 2.5rem;
            font-weight: 900;
            color: var(--primary);
            margin-bottom: 8px;
        }
.plan-price span {
            font-size: 1rem;
            font-weight: 400;
            color: #64748b;
        }
.plan-desc {
            color: #64748b;
            font-size: 0.9rem;
            margin-bottom: 24px;
        }
.plan-features {
            list-style: none;
            padding: 0;
            margin: 0 0 24px;
        }
.plan-features li {
            padding: 8px 0;
            font-size: 0.9rem;
            color: var(--text);
            border-bottom: 1px solid var(--border);
        }
.plan-features li:last-child {
            border-bottom: none;
        }
.plan-features li i {
            color: var(--primary);
            margin-right: 8px;
        }
.btn-plan {
            background: var(--primary);
            color: #fff;
            border: none;
            padding: 10px 28px;
            border-radius: var(--radius);
            font-weight: 600;
            width: 100%;
            transition: all 0.3s ease;
        }
.btn-plan:hover {
            background: #1d4ed8;
            transform: translateY(-2px);
        }
.btn-plan-outline {
            background: transparent;
            color: var(--primary);
            border: 2px solid var(--primary);
            padding: 8px 28px;
            border-radius: var(--radius);
            font-weight: 600;
            width: 100%;
            transition: all 0.3s ease;
        }
.btn-plan-outline:hover {
            background: var(--primary);
            color: #fff;
        }
.faq-item {
            background: #ffffff;
            border: 1px solid var(--border);
            border-radius: var(--radius);
            padding: 24px;
            margin-bottom: 16px;
            transition: all 0.3s ease;
        }
.faq-item:hover {
            border-color: var(--primary);
            box-shadow: var(--shadow-sm);
        }
.faq-item h4 {
            font-size: 1rem;
            font-weight: 700;
            color: var(--text);
            margin-bottom: 8px;
        }
.faq-item p {
            font-size: 0.9rem;
            color: #64748b;
            line-height: 1.7;
            margin: 0;
        }
.subscribe-note {
            background: rgba(37, 99, 235, 0.06);
            border: 1px dashed var(--primary);
            border-radius: var(--radius);
            padding: 16px 20px;
            margin-top: 24px;
            font-size: 0.85rem;
            color: #64748b;
        }
.subscribe-note i {
            color: var(--primary);
            margin-right: 8px;
        }
.subscribe-hero {
                padding: 48px 0 32px;
            }
.subscribe-form-wrap {
                padding: 24px;
                margin: 0 16px;
            }

/* --- 子页面追加 --- */
/* 隐私政策页面专属样式 */
        .privacy-hero {
            background: linear-gradient(135deg, #2563eb 0%, #06b6d4 100%);
            padding: 60px 0;
            color: white;
            text-align: center;
        }
.privacy-hero h1 {
            font-size: 2.5rem;
            font-weight: 800;
            margin-bottom: 1rem;
        }
.privacy-hero p {
            font-size: 1.1rem;
            opacity: 0.95;
            max-width: 700px;
            margin: 0 auto;
        }
.privacy-section {
            padding: 40px 0;
            border-bottom: 1px solid var(--border);
        }
.privacy-section:last-child {
            border-bottom: none;
        }
.privacy-section h2 {
            font-size: 1.5rem;
            font-weight: 700;
            color: var(--primary);
            margin-bottom: 1.2rem;
            display: flex;
            align-items: center;
            gap: 10px;
        }
.privacy-section h2 i {
            font-size: 1.3rem;
            color: var(--accent);
        }
.privacy-section p {
            color: var(--text);
            line-height: 1.8;
            margin-bottom: 1rem;
        }
.privacy-section ul {
            color: var(--text);
            line-height: 1.8;
            padding-left: 1.5rem;
            margin-bottom: 1rem;
        }
.privacy-section li {
            margin-bottom: 0.5rem;
        }
.privacy-updated {
            background: #f0f9ff;
            border: 1px solid #bae6fd;
            border-radius: var(--radius);
            padding: 12px 20px;
            color: #0369a1;
            font-size: 0.9rem;
            margin-top: 20px;
            display: inline-block;
        }
.privacy-contact {
            background: var(--card-bg);
            border-radius: var(--radius);
            padding: 24px;
            box-shadow: var(--shadow-sm);
            margin-top: 30px;
        }
.privacy-hero h1 {
                font-size: 1.8rem;
            }
.privacy-section h2 {
                font-size: 1.2rem;
            }

/* --- Bootstrap 组件配色适配(程序自动补,避免白底黑字) --- */
.form-select { background-color:#fff !important; color:#0f172a !important; border-color:rgba(0,0,0,.12) !important; }
.accordion-item { background:rgba(0,0,0,.03) !important; color:#0f172a !important; border-color:rgba(0,0,0,.12) !important; }
.accordion-button { background:rgba(0,0,0,.03) !important; color:#0f172a !important; }
.accordion-body { background:transparent !important; color:#0f172a !important; }
.accordion-header { background:transparent !important; }