:root {
            --bg-deep: #08070f;
            --bg-elevated: #0d0b18;
            --bg-card: rgba(255, 255, 255, 0.035);
            --bg-card-hover: rgba(255, 255, 255, 0.065);
            --border-subtle: rgba(255, 255, 255, 0.07);
            --border-active: rgba(139, 92, 246, 0.4);
            --text-primary: #f5f3ff;
            --text-secondary: #b8b3cc;
            --text-muted: #77728f;
            --accent-primary: #8b5cf6;
            --accent-secondary: #a78bfa;
            --accent-glow: rgba(139, 92, 246, 0.3);
            --accent-cyan: #22d3ee;
            --accent-green: #34d399;
            --accent-amber: #fbbf24;
            --accent-rose: #fb7185;
            --accent-blue: #60a5fa;
            --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, 'Noto Sans SC', sans-serif;
            --max-width: 1240px;
            --radius-sm: 8px;
            --radius-md: 14px;
            --radius-lg: 20px;
            --radius-xl: 28px;
            --transition-fast: 0.18s ease;
            --transition-base: 0.32s cubic-bezier(0.4, 0, 0.2, 1);
        }
        *,
        *::before,
        *::after {
            box-sizing: border-box;
            margin: 0;
            padding: 0;
        }
        html {
            scroll-behavior: smooth;
            -webkit-font-smoothing: antialiased;
            -moz-osx-font-smoothing: grayscale;
        }
        body {
            background-color: var(--bg-deep);
            color: var(--text-primary);
            font-family: var(--font-sans);
            line-height: 1.65;
            overflow-x: hidden;
            min-height: 100vh;
        }
        a {
            color: inherit;
            text-decoration: none;
            transition: color var(--transition-fast);
        }
        img {
            max-width: 100%;
            height: auto;
            display: block;
        }

        /* ============ 导航 ============ */
        .site-header {
            position: sticky;
            top: 0;
            z-index: 999;
            background: rgba(8, 7, 15, 0.88);
            backdrop-filter: blur(20px) saturate(1.4);
            -webkit-backdrop-filter: blur(20px) saturate(1.4);
            border-bottom: 1px solid var(--border-subtle);
            transition: background var(--transition-base), border-color var(--transition-base);
        }
        .site-header.scrolled {
            background: rgba(8, 7, 15, 0.97);
            border-bottom-color: rgba(139, 92, 246, 0.18);
            box-shadow: 0 8px 40px rgba(0, 0, 0, 0.5);
        }
        .nav-container {
            max-width: var(--max-width);
            margin: 0 auto;
            padding: 0.9rem 1.5rem;
            display: flex;
            align-items: center;
            justify-content: space-between;
            gap: 1rem;
        }
        .logo-link {
            display: flex;
            align-items: center;
            gap: 0.6rem;
            flex-shrink: 0;
        }
        .logo-icon {
            width: 34px;
            height: 34px;
            flex-shrink: 0;
        }
        .logo-icon .shield-path {
            fill: var(--accent-primary);
        }
        .logo-icon .shield-check {
            stroke: var(--accent-cyan);
            stroke-width: 1.6;
            fill: none;
            stroke-linecap: round;
            stroke-linejoin: round;
        }
        .logo-text {
            font-size: 1.4rem;
            font-weight: 800;
            letter-spacing: -0.02em;
            color: #fff;
            white-space: nowrap;
        }
        .logo-text .accent {
            color: var(--accent-secondary);
        }
        .nav-links {
            display: flex;
            align-items: center;
            gap: 0.2rem;
            list-style: none;
            flex-wrap: wrap;
        }
        .nav-links a {
            padding: 0.45rem 0.75rem;
            border-radius: var(--radius-sm);
            font-size: 0.85rem;
            font-weight: 500;
            color: var(--text-secondary);
            transition: all var(--transition-fast);
            white-space: nowrap;
            position: relative;
        }
        .nav-links a:hover {
            color: #fff;
            background: var(--bg-card);
        }
        .nav-links a.active {
            color: #fff;
            background: rgba(139, 92, 246, 0.16);
            box-shadow: inset 0 0 0 1px rgba(139, 92, 246, 0.35);
        }
        .nav-cta-btn {
            display: inline-flex;
            align-items: center;
            gap: 0.4rem;
            padding: 0.5rem 1.1rem;
            background: var(--accent-primary);
            color: #fff;
            font-size: 0.82rem;
            font-weight: 600;
            border-radius: 30px;
            border: none;
            cursor: pointer;
            transition: all var(--transition-fast);
            white-space: nowrap;
            flex-shrink: 0;
        }
        .nav-cta-btn:hover {
            background: var(--accent-secondary);
            box-shadow: 0 0 24px rgba(139, 92, 246, 0.5);
            transform: translateY(-1px);
        }
        .mobile-menu-toggle {
            display: none;
            background: none;
            border: none;
            cursor: pointer;
            padding: 0.4rem;
            border-radius: var(--radius-sm);
        }
        .mobile-menu-toggle svg {
            width: 24px;
            height: 24px;
            stroke: var(--text-primary);
            fill: none;
            stroke-width: 2;
        }

        /* ============ 页面头部 ============ */
        .page-header {
            padding: 4.5rem 0 2.5rem;
            text-align: center;
            position: relative;
            overflow: hidden;
            background:
                radial-gradient(ellipse 60% 45% at 50% -20%, rgba(139, 92, 246, 0.14), transparent 70%);
        }
        .page-header::after {
            content: '';
            position: absolute;
            inset: 0;
            background-image:
                linear-gradient(rgba(255, 255, 255, 0.02) 1px, transparent 1px),
                linear-gradient(90deg, rgba(255, 255, 255, 0.02) 1px, transparent 1px);
            background-size: 48px 48px;
            pointer-events: none;
            mask-image: radial-gradient(ellipse 60% 50% at 50% 0%, black 30%, transparent 80%);
            -webkit-mask-image: radial-gradient(ellipse 60% 50% at 50% 0%, black 30%, transparent 80%);
        }
        .page-header-container {
            max-width: var(--max-width);
            margin: 0 auto;
            padding: 0 1.5rem;
            position: relative;
            z-index: 1;
        }
        .page-badge {
            display: inline-flex;
            align-items: center;
            gap: 0.4rem;
            padding: 0.35rem 0.9rem;
            background: rgba(139, 92, 246, 0.14);
            border: 1px solid rgba(139, 92, 246, 0.3);
            border-radius: 30px;
            font-size: 0.75rem;
            font-weight: 600;
            color: var(--accent-secondary);
            margin-bottom: 1.2rem;
            letter-spacing: 0.03em;
        }
        .page-title {
            font-size: 3rem;
            font-weight: 900;
            letter-spacing: -0.04em;
            color: #fff;
            line-height: 1.15;
            margin-bottom: 1rem;
        }
        .page-title .highlight {
            background: linear-gradient(135deg, var(--accent-primary) 0%, var(--accent-cyan) 100%);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
        }
        .page-desc {
            font-size: 1.05rem;
            color: var(--text-secondary);
            max-width: 720px;
            margin: 0 auto 1.8rem;
            line-height: 1.7;
        }
        .page-stats {
            display: flex;
            justify-content: center;
            gap: 2.5rem;
            flex-wrap: wrap;
        }
        .page-stat {
            text-align: center;
        }
        .page-stat .num {
            font-size: 1.5rem;
            font-weight: 800;
            color: #fff;
        }
        .page-stat .num .suffix {
            font-size: 0.8rem;
            font-weight: 600;
            color: var(--accent-secondary);
        }
        .page-stat .label {
            font-size: 0.7rem;
            color: var(--text-muted);
            letter-spacing: 0.03em;
        }

        /* ============ 下载卡片区 ============ */
        .download-section {
            padding: 3rem 0 5rem;
        }
        .section-container {
            max-width: var(--max-width);
            margin: 0 auto;
            padding: 0 1.5rem;
        }
        .download-grid {
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            gap: 1.3rem;
            margin-bottom: 3rem;
        }
        .download-card {
            background: var(--bg-card);
            border: 1px solid var(--border-subtle);
            border-radius: var(--radius-lg);
            padding: 1.8rem 1.3rem;
            transition: all var(--transition-base);
            display: flex;
            flex-direction: column;
            position: relative;
            overflow: hidden;
        }
        .download-card.featured {
            border-color: var(--border-active);
            background: radial-gradient(circle at top right, rgba(139, 92, 246, 0.15), rgba(255, 255, 255, 0.03));
            box-shadow: 0 0 35px rgba(139, 92, 246, 0.22);
        }
        .download-card:hover {
            border-color: var(--border-active);
            background: var(--bg-card-hover);
            transform: translateY(-4px);
        }
        .download-card.featured:hover {
            box-shadow: 0 8px 40px rgba(139, 92, 246, 0.3);
        }
        .platform-header {
            display: flex;
            align-items: center;
            gap: 0.8rem;
            margin-bottom: 1.2rem;
        }
        .platform-header svg {
            width: 38px;
            height: 38px;
            fill: var(--accent-primary);
            flex-shrink: 0;
        }
        .download-card:nth-child(2) .platform-header svg {
            fill: var(--accent-green);
        }
        .download-card:nth-child(3) .platform-header svg {
            fill: var(--accent-cyan);
        }
        .download-card:nth-child(4) .platform-header svg {
            fill: var(--accent-amber);
        }
        .platform-header h2 {
            font-size: 1.2rem;
            font-weight: 700;
            color: #fff;
            letter-spacing: -0.01em;
        }
        .version-meta {
            font-size: 0.75rem;
            color: var(--text-muted);
            margin-bottom: 1.2rem;
            line-height: 1.4;
        }
        .version-meta span {
            display: block;
        }
        .btn-download {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            gap: 0.4rem;
            background: var(--accent-primary);
            color: #fff;
            font-weight: 700;
            font-size: 0.85rem;
            padding: 0.7rem 1.2rem;
            border-radius: 30px;
            text-align: center;
            transition: all var(--transition-fast);
            margin-bottom: 1.2rem;
            border: none;
            cursor: pointer;
            white-space: nowrap;
        }
        .download-card.featured .btn-download {
            box-shadow: 0 4px 20px rgba(139, 92, 246, 0.4);
        }
        .btn-download:hover {
            background: var(--accent-secondary);
            transform: translateY(-2px);
            box-shadow: 0 6px 24px rgba(139, 92, 246, 0.5);
        }
        .btn-download.btn-outline {
            background: rgba(255, 255, 255, 0.08);
            color: #fff;
            box-shadow: none;
        }
        .btn-download.btn-outline:hover {
            background: rgba(255, 255, 255, 0.15);
        }
        .checksum-box {
            background: rgba(0, 0, 0, 0.3);
            border: 1px solid var(--border-subtle);
            border-radius: var(--radius-sm);
            padding: 0.6rem 0.8rem;
            font-size: 0.65rem;
            color: var(--text-muted);
            word-break: break-all;
            margin-bottom: 0.8rem;
        }
        .checksum-box .label {
            color: var(--text-secondary);
            font-weight: 600;
        }
        .feature-mini-list {
            list-style: none;
            margin-top: auto;
        }
        .feature-mini-list li {
            font-size: 0.72rem;
            color: var(--text-muted);
            margin-bottom: 0.35rem;
            display: flex;
            align-items: center;
            gap: 0.4rem;
        }
        .feature-mini-list li::before {
            content: "✓";
            color: var(--accent-green);
            font-weight: bold;
            flex-shrink: 0;
        }

        /* ============ 安全下载保障 ============ */
        .security-download-section {
            padding: 4rem 0;
            background: var(--bg-elevated);
            border-top: 1px solid var(--border-subtle);
            border-bottom: 1px solid var(--border-subtle);
        }
        .security-download-grid {
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            gap: 1.2rem;
            margin-top: 2.5rem;
        }
        .security-item {
            text-align: center;
            padding: 1.8rem 1rem;
            background: var(--bg-card);
            border: 1px solid var(--border-subtle);
            border-radius: var(--radius-md);
            transition: all var(--transition-fast);
        }
        .security-item:hover {
            border-color: var(--border-active);
            background: var(--bg-card-hover);
            transform: translateY(-3px);
        }
        .security-item .sec-icon {
            width: 48px;
            height: 48px;
            border-radius: 50%;
            margin: 0 auto 0.8rem;
            display: flex;
            align-items: center;
            justify-content: center;
            background: rgba(139, 92, 246, 0.12);
            border: 1px solid rgba(139, 92, 246, 0.2);
        }
        .security-item .sec-icon svg {
            width: 22px;
            height: 22px;
            stroke: var(--accent-secondary);
            fill: none;
            stroke-width: 1.8;
        }
        .security-item h3 {
            font-size: 0.9rem;
            font-weight: 700;
            color: #fff;
            margin-bottom: 0.35rem;
        }
        .security-item p {
            font-size: 0.75rem;
            color: var(--text-muted);
            line-height: 1.5;
        }

        /* ============ 版本对比表 ============ */
        .version-compare-section {
            padding: 4.5rem 0;
        }
        .compare-table-wrap {
            overflow-x: auto;
            margin-top: 2rem;
            border-radius: var(--radius-lg);
            border: 1px solid var(--border-subtle);
            background: var(--bg-card);
        }
        .compare-table {
            width: 100%;
            border-collapse: collapse;
            min-width: 720px;
            font-size: 0.85rem;
        }
        .compare-table th {
            padding: 1rem 1.2rem;
            text-align: left;
            font-weight: 700;
            color: #fff;
            background: rgba(139, 92, 246, 0.1);
            border-bottom: 1px solid var(--border-subtle);
        }
        .compare-table td {
            padding: 0.9rem 1.2rem;
            color: var(--text-secondary);
            border-bottom: 1px solid var(--border-subtle);
        }
        .compare-table tr:last-child td {
            border-bottom: none;
        }
        .compare-table .feature-name {
            color: #fff;
            font-weight: 600;
        }
        .check-yes {
            color: var(--accent-green);
            font-weight: 700;
        }
        .check-no {
            color: var(--text-muted);
        }

        /* ============ 安装指南 ============ */
        .install-guide-section {
            padding: 4.5rem 0;
            background: var(--bg-elevated);
            border-top: 1px solid var(--border-subtle);
            border-bottom: 1px solid var(--border-subtle);
        }
        .install-steps {
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            gap: 1.2rem;
            margin-top: 2.5rem;
        }
        .install-step {
            text-align: center;
            padding: 1.5rem 1rem;
            background: var(--bg-card);
            border: 1px solid var(--border-subtle);
            border-radius: var(--radius-md);
            position: relative;
        }
        .install-step .step-num {
            width: 36px;
            height: 36px;
            border-radius: 50%;
            background: var(--accent-primary);
            color: #fff;
            font-weight: 800;
            font-size: 0.85rem;
            display: flex;
            align-items: center;
            justify-content: center;
            margin: 0 auto 0.7rem;
        }
        .install-step h3 {
            font-size: 0.9rem;
            font-weight: 700;
            color: #fff;
            margin-bottom: 0.3rem;
        }
        .install-step p {
            font-size: 0.75rem;
            color: var(--text-muted);
            line-height: 1.5;
        }

        /* ============ 用户评价 ============ */
        .testimonial-grid {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 1.2rem;
            margin-top: 2.5rem;
        }
        .testimonial-card {
            background: var(--bg-card);
            border: 1px solid var(--border-subtle);
            border-radius: var(--radius-lg);
            padding: 1.5rem 1.3rem;
            transition: all var(--transition-fast);
        }
        .testimonial-card:hover {
            border-color: var(--border-active);
            background: var(--bg-card-hover);
        }
        .testimonial-stars {
            display: flex;
            gap: 0.15rem;
            margin-bottom: 0.7rem;
        }
        .testimonial-stars svg {
            width: 13px;
            height: 13px;
            fill: var(--accent-amber);
        }
        .testimonial-text {
            font-size: 0.82rem;
            color: var(--text-secondary);
            line-height: 1.6;
            margin-bottom: 0.8rem;
            font-style: italic;
        }
        .testimonial-author {
            display: flex;
            align-items: center;
            gap: 0.5rem;
        }
        .testimonial-avatar {
            width: 30px;
            height: 30px;
            border-radius: 50%;
            background: linear-gradient(135deg, var(--accent-primary), var(--accent-cyan));
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 0.65rem;
            font-weight: 700;
            color: #fff;
        }
        .testimonial-name {
            font-size: 0.75rem;
            font-weight: 600;
            color: #fff;
        }
        .testimonial-role {
            font-size: 0.65rem;
            color: var(--text-muted);
        }

        /* ============ FAQ 摘要 ============ */
        .faq-preview {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 0.9rem;
            margin-top: 2.5rem;
        }
        .faq-item {
            padding: 1.1rem 1.3rem;
            background: var(--bg-card);
            border: 1px solid var(--border-subtle);
            border-radius: var(--radius-md);
            transition: all var(--transition-fast);
            cursor: pointer;
        }
        .faq-item:hover {
            border-color: var(--border-active);
            background: var(--bg-card-hover);
        }
        .faq-item h4 {
            font-size: 0.85rem;
            font-weight: 600;
            color: #fff;
            margin-bottom: 0.3rem;
        }
        .faq-item p {
            font-size: 0.75rem;
            color: var(--text-muted);
            line-height: 1.5;
        }

        /* ============ CTA ============ */
        .cta-box {
            background: linear-gradient(135deg, rgba(139, 92, 246, 0.2) 0%, rgba(34, 211, 238, 0.1) 50%, rgba(139, 92, 246, 0.12) 100%);
            border: 1px solid rgba(139, 92, 246, 0.3);
            border-radius: var(--radius-xl);
            padding: 3rem 2.5rem;
            text-align: center;
            margin-top: 4rem;
            position: relative;
            overflow: hidden;
        }
        .cta-box::before {
            content: '';
            position: absolute;
            top: -50%;
            left: -50%;
            width: 200%;
            height: 200%;
            background: conic-gradient(from 0deg, transparent, rgba(139, 92, 246, 0.06), transparent, rgba(34, 211, 238, 0.06), transparent);
            animation: cta-shimmer 12s linear infinite;
            pointer-events: none;
        }
        @keyframes cta-shimmer {
            from { transform: rotate(0deg); }
            to { transform: rotate(360deg); }
        }
        .cta-box h2 {
            font-size: 1.8rem;
            font-weight: 800;
            color: #fff;
            letter-spacing: -0.025em;
            margin-bottom: 0.6rem;
            position: relative;
            z-index: 1;
        }
        .cta-box p {
            font-size: 0.9rem;
            color: var(--text-secondary);
            max-width: 520px;
            margin: 0 auto 1.5rem;
            position: relative;
            z-index: 1;
        }
        .cta-actions {
            display: flex;
            gap: 0.9rem;
            justify-content: center;
            flex-wrap: wrap;
            position: relative;
            z-index: 1;
        }

        /* ============ Footer ============ */
        .site-footer {
            background: #06050c;
            border-top: 1px solid var(--border-subtle);
            padding: 4rem 0 2rem;
        }
        .footer-container {
            max-width: var(--max-width);
            margin: 0 auto;
            padding: 0 1.5rem;
        }
        .footer-grid {
            display: grid;
            grid-template-columns: 2fr 1fr 1fr 1.2fr;
            gap: 2.5rem;
            margin-bottom: 3rem;
        }
        .footer-brand .logo-text {
            font-size: 1.25rem;
            margin-bottom: 0.6rem;
            display: inline-block;
        }
        .footer-brand p {
            font-size: 0.8rem;
            color: var(--text-muted);
            line-height: 1.6;
            max-width: 300px;
        }
        .footer-col h4 {
            font-size: 0.8rem;
            font-weight: 700;
            letter-spacing: 0.06em;
            text-transform: uppercase;
            color: #fff;
            margin-bottom: 1rem;
        }
        .footer-col ul {
            list-style: none;
        }
        .footer-col ul li {
            margin-bottom: 0.45rem;
        }
        .footer-col ul a {
            font-size: 0.8rem;
            color: var(--text-muted);
            transition: color var(--transition-fast);
        }
        .footer-col ul a:hover {
            color: var(--accent-secondary);
        }
        .footer-bottom {
            padding-top: 2rem;
            border-top: 1px solid var(--border-subtle);
            display: flex;
            justify-content: space-between;
            align-items: center;
            flex-wrap: wrap;
            gap: 0.8rem;
            font-size: 0.72rem;
            color: var(--text-muted);
        }
        .footer-bottom a {
            color: var(--accent-secondary);
        }
        .footer-bottom a:hover {
            color: var(--accent-primary);
        }

        /* ============ 响应式 ============ */
        @media (max-width: 1024px) {
            .download-grid {
                grid-template-columns: repeat(2, 1fr);
            }
            .security-download-grid,
            .install-steps {
                grid-template-columns: repeat(2, 1fr);
            }
            .testimonial-grid {
                grid-template-columns: repeat(2, 1fr);
            }
        }
        @media (max-width: 768px) {
            .nav-links {
                display: none;
                position: absolute;
                top: 100%;
                left: 0;
                right: 0;
                background: rgba(8, 7, 15, 0.98);
                border-bottom: 1px solid var(--border-subtle);
                padding: 1rem 1.5rem;
                flex-direction: column;
                align-items: stretch;
                gap: 0.3rem;
            }
            .nav-links.open {
                display: flex;
            }
            .nav-links a {
                padding: 0.65rem 1rem;
                border-radius: var(--radius-sm);
            }
            .mobile-menu-toggle {
                display: block;
            }
            .nav-cta-btn {
                display: none;
            }
            .page-title {
                font-size: 2.2rem;
            }
            .download-grid {
                grid-template-columns: 1fr;
            }
            .security-download-grid,
            .install-steps {
                grid-template-columns: 1fr;
            }
            .testimonial-grid {
                grid-template-columns: 1fr;
            }
            .faq-preview {
                grid-template-columns: 1fr;
            }
            .footer-grid {
                grid-template-columns: 1fr 1fr;
            }
        }
        @media (max-width: 480px) {
            .page-title {
                font-size: 1.8rem;
            }
            .page-stats {
                gap: 1.5rem;
                flex-direction: column;
                align-items: center;
            }
            .footer-grid {
                grid-template-columns: 1fr;
            }
            .footer-bottom {
                flex-direction: column;
                text-align: center;
            }
            .cta-box {
                padding: 2rem 1.2rem;
            }
            .cta-box h2 {
                font-size: 1.4rem;
            }
        }