*, *::before, *::after {
            box-sizing: border-box;
            margin: 0;
            padding: 0;
        }
        :root {
            --primary: #0f4c81;
            --primary-dark: #0a3559;
            --accent: #00c9a7;
            --accent-hover: #00b394;
            --bg: #f6fafd;
            --card: #ffffff;
            --text: #1a2b3c;
            --text-secondary: #4d6277;
            --border: #e8eef5;
            --shadow: 0 8px 30px rgba(15, 76, 129, 0.08);
            --shadow-hover: 0 16px 48px rgba(15, 76, 129, 0.16);
            --radius: 18px;
            --radius-sm: 12px;
            --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
        }
        body {
            font-family: 'Inter', 'PingFang SC', 'Microsoft YaHei', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
            line-height: 1.75;
            color: var(--text);
            background-color: var(--bg);
            overflow-x: hidden;
            -webkit-font-smoothing: antialiased;
            -moz-osx-font-smoothing: grayscale;
        }
        a { color: inherit; text-decoration: none; transition: color var(--transition); }
        img { max-width: 100%; display: block; }
        .header {
            background: rgba(255, 255, 255, 0.92);
            backdrop-filter: blur(20px);
            -webkit-backdrop-filter: blur(20px);
            border-bottom: 1px solid var(--border);
            position: sticky;
            top: 0;
            z-index: 1000;
            box-shadow: 0 2px 20px rgba(0, 0, 0, 0.04);
            transition: box-shadow var(--transition);
        }
        .header.scrolled { box-shadow: 0 4px 32px rgba(15, 76, 129, 0.1); }
        .nav-container {
            max-width: 1360px;
            margin: 0 auto;
            padding: 0.6rem 2rem;
            display: flex;
            align-items: center;
            justify-content: space-between;
            gap: 1rem;
            flex-wrap: wrap;
        }
        .logo-link {
            display: flex;
            align-items: center;
            gap: 10px;
            font-size: 1.5rem;
            font-weight: 800;
            color: var(--primary);
            letter-spacing: -0.5px;
            white-space: nowrap;
        }
        .logo-icon { width: 40px; height: 40px; flex-shrink: 0; }
        .nav-links {
            display: flex;
            align-items: center;
            gap: 0.25rem;
            flex-wrap: wrap;
            list-style: none;
        }
        .nav-links a {
            padding: 0.5rem 1rem;
            font-weight: 600;
            font-size: 0.9rem;
            color: var(--text-secondary);
            border-radius: 30px;
            transition: all var(--transition);
            white-space: nowrap;
        }
        .nav-links a:hover, .nav-links a.active {
            color: var(--primary);
            background: rgba(15, 76, 129, 0.06);
        }
        .nav-links a.active {
            font-weight: 700;
            background: rgba(15, 76, 129, 0.1);
        }
        .nav-cta {
            background: var(--accent);
            color: #fff !important;
            padding: 0.55rem 1.4rem !important;
            border-radius: 30px !important;
            font-weight: 700 !important;
            box-shadow: 0 4px 16px rgba(0, 201, 167, 0.35);
        }
        .nav-cta:hover {
            background: var(--accent-hover) !important;
            transform: translateY(-1px);
            box-shadow: 0 8px 24px rgba(0, 201, 167, 0.45);
        }

        .hero {
            position: relative;
            background: linear-gradient(160deg, #081c34 0%, #0f4c81 45%, #0a3d6b 100%);
            color: #fff;
            padding: 5rem 2rem 5.5rem;
            text-align: center;
            overflow: hidden;
        }
        .hero::before {
            content: '';
            position: absolute;
            top: -50%;
            left: -50%;
            width: 200%;
            height: 200%;
            background: radial-gradient(ellipse at 30% 20%, rgba(0, 201, 167, 0.12) 0%, transparent 55%),
                radial-gradient(ellipse at 70% 80%, rgba(15, 76, 129, 0.4) 0%, transparent 50%);
            animation: heroGlow 12s ease-in-out infinite alternate;
            pointer-events: none;
        }
        @keyframes heroGlow {
            0% { transform: translate(0, 0) rotate(0deg); }
            100% { transform: translate(3%, -3%) rotate(3deg); }
        }
        .hero-content { position: relative; z-index: 1; max-width: 950px; margin: 0 auto; }
        .hero-badge {
            display: inline-block;
            background: rgba(255,255,255,0.1);
            border: 1px solid rgba(255,255,255,0.2);
            padding: 0.4rem 1.2rem;
            border-radius: 30px;
            font-size: 0.85rem;
            font-weight: 600;
            letter-spacing: 0.5px;
            margin-bottom: 2rem;
            color: rgba(255,255,255,0.85);
        }
        .hero-badge span { color: var(--accent); font-weight: 700; }
        .hero h1 {
            font-size: clamp(2.2rem, 5vw, 3.5rem);
            line-height: 1.2;
            margin-bottom: 1.5rem;
            font-weight: 800;
            letter-spacing: -1px;
        }
        .hero h1 .highlight {
            background: linear-gradient(135deg, #00e5c0, #00c9a7);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
        }
        .hero p {
            font-size: 1.2rem;
            opacity: 0.88;
            max-width: 750px;
            margin: 0 auto 2.5rem;
            line-height: 1.9;
        }
        .btn-primary {
            display: inline-block;
            background: var(--accent);
            color: #fff;
            padding: 0.9rem 2.4rem;
            border-radius: 50px;
            font-weight: 700;
            font-size: 1.05rem;
            box-shadow: 0 8px 24px rgba(0, 201, 167, 0.4);
            transition: all var(--transition);
            border: none;
            cursor: pointer;
        }
        .btn-primary:hover {
            background: var(--accent-hover);
            transform: translateY(-3px);
            box-shadow: 0 12px 36px rgba(0, 201, 167, 0.55);
        }
        .btn-secondary {
            display: inline-block;
            background: rgba(255,255,255,0.08);
            color: #fff;
            padding: 0.9rem 2.4rem;
            border-radius: 50px;
            font-weight: 600;
            font-size: 1.05rem;
            border: 1px solid rgba(255,255,255,0.25);
            transition: all var(--transition);
        }
        .btn-secondary:hover {
            background: rgba(255,255,255,0.15);
            border-color: rgba(255,255,255,0.4);
            transform: translateY(-3px);
        }

        .container {
            max-width: 1200px;
            margin: 0 auto;
            padding: 3.5rem 2rem;
        }
        .section-title {
            text-align: center;
            font-size: clamp(1.8rem, 3vw, 2.4rem);
            margin-bottom: 0.8rem;
            color: var(--text);
            font-weight: 800;
            letter-spacing: -0.5px;
        }
        .section-subtitle {
            text-align: center;
            font-size: 1.05rem;
            color: var(--text-secondary);
            max-width: 680px;
            margin: 0 auto 3rem;
            line-height: 1.8;
        }

        .download-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
            gap: 1.8rem;
            margin: 2rem 0;
        }
        .platform-card {
            background: var(--card);
            padding: 2rem 1.8rem;
            border-radius: var(--radius);
            border: 1px solid var(--border);
            transition: all var(--transition);
            text-align: center;
            display: flex;
            flex-direction: column;
        }
        .platform-card:hover {
            transform: translateY(-6px);
            box-shadow: var(--shadow-hover);
            border-color: rgba(15,76,129,0.2);
        }
        .platform-icon {
            font-size: 2.8rem;
            margin-bottom: 1rem;
        }
        .platform-card h3 {
            font-size: 1.3rem;
            font-weight: 700;
            margin-bottom: 0.3rem;
        }
        .version-tag {
            display: inline-block;
            background: rgba(0,201,167,0.1);
            color: var(--accent);
            padding: 0.2rem 0.8rem;
            border-radius: 20px;
            font-size: 0.8rem;
            font-weight: 600;
            margin-bottom: 0.8rem;
        }
        .platform-card p {
            font-size: 0.92rem;
            color: var(--text-secondary);
            margin-bottom: 1.2rem;
            flex: 1;
        }
        .download-btn {
            display: inline-block;
            background: var(--primary);
            color: #fff;
            padding: 0.8rem 1.8rem;
            border-radius: 40px;
            font-weight: 700;
            font-size: 0.95rem;
            transition: all var(--transition);
            border: none;
            cursor: pointer;
        }
        .download-btn:hover {
            background: var(--primary-dark);
            transform: translateY(-2px);
            box-shadow: 0 6px 16px rgba(15,76,129,0.3);
        }
        .checksum {
            font-size: 0.75rem;
            color: #8899aa;
            margin-top: 0.8rem;
            word-break: break-all;
        }

        .security-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
            gap: 1.5rem;
            margin: 2.5rem 0;
        }
        .security-item {
            background: #fff;
            padding: 1.8rem;
            border-radius: var(--radius-sm);
            text-align: center;
            border: 1px solid var(--border);
            transition: all var(--transition);
        }
        .security-item:hover { box-shadow: var(--shadow); transform: translateY(-3px); }
        .security-icon { font-size: 2rem; margin-bottom: 0.8rem; }
        .security-item h4 { font-weight: 700; margin-bottom: 0.5rem; font-size: 1.05rem; }
        .security-item p { font-size: 0.9rem; color: var(--text-secondary); }

        .steps-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
            gap: 1.5rem;
            margin: 2.5rem 0;
        }
        .step-card {
            background: #fff;
            padding: 2rem 1.5rem;
            border-radius: var(--radius);
            border: 1px solid var(--border);
            position: relative;
            text-align: center;
            transition: all var(--transition);
        }
        .step-card:hover { box-shadow: var(--shadow); }
        .step-number {
            width: 40px;
            height: 40px;
            background: var(--accent);
            color: #fff;
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            font-weight: 800;
            font-size: 1.2rem;
            margin: 0 auto 1rem;
        }
        .step-card h4 { font-weight: 700; margin-bottom: 0.5rem; }
        .step-card p { font-size: 0.9rem; color: var(--text-secondary); }

        .requirements-table {
            background: #fff;
            border-radius: var(--radius);
            box-shadow: var(--shadow);
            overflow: hidden;
            margin: 2rem 0;
        }
        .requirements-table table {
            width: 100%;
            border-collapse: collapse;
            min-width: 600px;
        }
        .requirements-table th, .requirements-table td {
            padding: 1rem 1.5rem;
            text-align: left;
            border-bottom: 1px solid var(--border);
            font-size: 0.95rem;
        }
        .requirements-table th {
            background: #f0f7fb;
            font-weight: 700;
            color: var(--primary);
        }
        .requirements-table tr:last-child td { border-bottom: none; }

        .faq-list {
            max-width: 800px;
            margin: 0 auto;
            background: #fff;
            border-radius: var(--radius);
            box-shadow: var(--shadow);
            padding: 0.5rem 2rem;
        }
        .faq-item {
            border-bottom: 1px solid var(--border);
            padding: 1.2rem 0;
            cursor: pointer;
        }
        .faq-item:last-child { border-bottom: none; }
        .faq-question {
            display: flex;
            justify-content: space-between;
            align-items: center;
            font-weight: 700;
            font-size: 1.05rem;
            color: var(--text);
            gap: 1rem;
        }
        .faq-answer {
            max-height: 0;
            overflow: hidden;
            transition: max-height 0.4s ease-out, padding-top 0.3s ease-out;
            color: var(--text-secondary);
            font-size: 0.95rem;
            padding-top: 0;
        }
        .faq-item.active .faq-answer { max-height: 600px; padding-top: 1rem; }
        .faq-icon { transition: transform 0.3s; font-size: 1.2rem; color: var(--accent); flex-shrink: 0; }
        .faq-item.active .faq-icon { transform: rotate(180deg); }

        .download-stats {
            background: linear-gradient(135deg, #081c34 0%, #0f4c81 100%);
            border-radius: var(--radius);
            padding: 3rem 2rem;
            text-align: center;
            color: #fff;
            margin: 3rem 0;
        }
        .download-stats h2 {
            font-size: 2rem;
            font-weight: 800;
            margin-bottom: 1rem;
        }
        .stats-inline {
            display: flex;
            flex-wrap: wrap;
            gap: 2rem;
            justify-content: center;
            margin-top: 2rem;
        }
        .stat-inline-item {
            text-align: center;
        }
        .stat-inline-number {
            font-size: 2.2rem;
            font-weight: 800;
            color: var(--accent);
        }
        .stat-inline-label {
            font-size: 0.9rem;
            opacity: 0.8;
        }

        footer {
            background: #081c34;
            color: #a0b8cc;
            padding: 4rem 2rem 2rem;
            font-size: 0.9rem;
            margin-top: 4rem;
        }
        .footer-content {
            max-width: 1300px;
            margin: 0 auto;
            display: grid;
            grid-template-columns: 2fr 1fr 1fr 1fr;
            gap: 2.5rem;
        }
        .footer-col h5 { color: #fff; font-size: 1rem; margin-bottom: 1.2rem; font-weight: 700; }
        .footer-col ul { list-style: none; }
        .footer-col li { margin-bottom: 0.6rem; }
        .footer-col a { color: #a0b8cc; transition: color var(--transition); }
        .footer-col a:hover { color: #fff; }
        .footer-bottom {
            text-align: center;
            margin-top: 3rem;
            padding-top: 1.5rem;
            border-top: 1px solid rgba(255,255,255,0.1);
            opacity: 0.7;
            font-size: 0.85rem;
        }

        @media (max-width: 900px) {
            .nav-container { flex-direction: column; align-items: center; gap: 0.5rem; }
            .nav-links { justify-content: center; }
            .footer-content { grid-template-columns: 1fr 1fr; }
        }
        @media (max-width: 600px) {
            .footer-content { grid-template-columns: 1fr; }
            .download-grid { grid-template-columns: 1fr; }
        }