:root {
            --bg-main: #060813;
            --bg-surface: #0e1329;
            --bg-card: rgba(18, 26, 52, 0.65);
            --bg-card-alt: rgba(14, 19, 41, 0.8);
            --border-color: rgba(99, 102, 241, 0.2);
            --border-hover: rgba(168, 85, 247, 0.5);
            --border-cyan: rgba(6, 182, 212, 0.35);
            --primary: #6366f1;
            --secondary: #a855f7;
            --cyan: #06b6d4;
            --green: #10b981;
            --amber: #f59e0b;
            --text-main: #f8fafc;
            --text-muted: #94a3b8;
            --text-dim: #64748b;
            --glow-cyan: rgba(6, 182, 212, 0.25);
            --glow-purple: rgba(168, 85, 247, 0.2);
            --radius-sm: 8px;
            --radius-md: 14px;
            --radius-lg: 20px;
            --radius-xl: 28px;
            --transition-fast: 0.2s ease;
            --transition-smooth: 0.35s cubic-bezier(0.4, 0, 0.2, 1);
        }

        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
            font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "PingFang SC", "Microsoft YaHei", sans-serif;
        }

        body {
            background-color: var(--bg-main);
            color: var(--text-main);
            line-height: 1.65;
            overflow-x: hidden;
            -webkit-font-smoothing: antialiased;
        }

        /* 极光背景 */
        .bg-aurora {
            position: fixed;
            top: 0;
            left: 0;
            width: 100vw;
            height: 100vh;
            z-index: -1;
            pointer-events: none;
            overflow: hidden;
        }
        .aurora-1 {
            position: absolute;
            top: -10%;
            right: 10%;
            width: 50vw;
            height: 50vw;
            background: radial-gradient(circle, rgba(168, 85, 247, 0.15) 0%, rgba(0,0,0,0) 70%);
            filter: blur(120px);
            animation: auroraDrift1 18s ease-in-out infinite;
        }
        .aurora-2 {
            position: absolute;
            bottom: -10%;
            left: -10%;
            width: 45vw;
            height: 45vw;
            background: radial-gradient(circle, rgba(6, 182, 212, 0.15) 0%, rgba(0,0,0,0) 70%);
            filter: blur(100px);
            animation: auroraDrift2 22s ease-in-out infinite;
        }
        .aurora-3 {
            position: absolute;
            top: 40%;
            left: 30%;
            width: 40vw;
            height: 40vw;
            background: radial-gradient(circle, rgba(99, 102, 241, 0.12) 0%, rgba(0,0,0,0) 70%);
            filter: blur(90px);
            animation: auroraDrift3 20s ease-in-out infinite;
        }
        @keyframes auroraDrift1 {
            0%,100%{transform:translate(0,0) scale(1);}
            33%{transform:translate(-2vw,2vw) scale(1.06);}
            66%{transform:translate(2vw,-1.5vw) scale(0.95);}
        }
        @keyframes auroraDrift2 {
            0%,100%{transform:translate(0,0) scale(1);}
            40%{transform:translate(3vw,-2vw) scale(1.08);}
            75%{transform:translate(-2.5vw,1.5vw) scale(0.92);}
        }
        @keyframes auroraDrift3 {
            0%,100%{transform:translate(0,0) scale(1);}
            50%{transform:translate(1.5vw,-2.5vw) scale(1.05);}
        }

        /* 导航栏 —— 与首页基调完全一致 */
        header {
            position: sticky;
            top: 0;
            z-index: 1000;
            background: rgba(6, 8, 19, 0.82);
            backdrop-filter: blur(22px);
            -webkit-backdrop-filter: blur(22px);
            border-bottom: 1px solid var(--border-color);
        }
        .header-wrap {
            max-width: 1280px;
            margin: 0 auto;
            padding: 0.9rem 2rem;
            display: flex;
            align-items: center;
            justify-content: space-between;
            gap: 1rem;
        }
        .brand {
            display: flex;
            align-items: center;
            gap: 0.7rem;
            text-decoration: none;
            color: #fff;
            flex-shrink: 0;
        }
        .brand-logo {
            width: 38px;
            height: 38px;
            background: linear-gradient(135deg, var(--cyan), var(--primary), var(--secondary));
            border-radius: 11px;
            display: flex;
            align-items: center;
            justify-content: center;
            box-shadow: 0 0 22px rgba(6, 182, 212, 0.45);
        }
        .brand:hover .brand-logo {
            box-shadow: 0 0 32px rgba(6, 182, 212, 0.7);
            transform: scale(1.04);
        }
        .brand-title {
            font-size: 1.3rem;
            font-weight: 800;
            letter-spacing: -0.5px;
            background: linear-gradient(135deg, #ffffff 40%, #bae6fd 100%);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
        }
        .nav-menu {
            display: flex;
            list-style: none;
            gap: 1.6rem;
            flex-wrap: wrap;
        }
        .nav-link {
            color: var(--text-muted);
            text-decoration: none;
            font-size: 0.93rem;
            font-weight: 500;
            transition: color var(--transition-fast);
            position: relative;
            white-space: nowrap;
        }
        .nav-link::after {
            content: '';
            position: absolute;
            bottom: -4px;
            left: 0;
            width: 0;
            height: 2px;
            background: var(--cyan);
            border-radius: 2px;
            transition: width var(--transition-smooth);
        }
        .nav-link:hover,
        .nav-link.active {
            color: var(--cyan);
        }
        .nav-link:hover::after,
        .nav-link.active::after {
            width: 100%;
        }
        .nav-btn {
            background: linear-gradient(135deg, var(--cyan), var(--primary));
            color: #fff;
            padding: 0.6rem 1.4rem;
            border-radius: var(--radius-sm);
            text-decoration: none;
            font-size: 0.88rem;
            font-weight: 600;
            box-shadow: 0 4px 16px rgba(6, 182, 212, 0.3);
            transition: all var(--transition-smooth);
            white-space: nowrap;
            flex-shrink: 0;
        }
        .nav-btn:hover {
            transform: translateY(-2px);
            box-shadow: 0 8px 24px rgba(6, 182, 212, 0.55);
            background: linear-gradient(135deg, #22d3ee, var(--primary));
        }

        /* 页面头部 */
        .page-header {
            text-align: center;
            max-width: 850px;
            margin: 4rem auto 2.5rem;
            padding: 0 1.5rem;
        }
        .page-header .badge {
            display: inline-flex;
            align-items: center;
            gap: 0.4rem;
            background: rgba(16, 185, 129, 0.08);
            border: 1px solid rgba(16, 185, 129, 0.3);
            color: var(--green);
            padding: 0.3rem 1rem;
            border-radius: 99px;
            font-size: 0.8rem;
            font-weight: 600;
            margin-bottom: 1.2rem;
        }
        .page-header h1 {
            font-size: 2.8rem;
            font-weight: 800;
            margin-bottom: 1rem;
            letter-spacing: -0.5px;
        }
        .text-gradient {
            background: linear-gradient(135deg, #fff 20%, var(--cyan) 60%, var(--secondary) 100%);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
        }
        .page-header p {
            color: var(--text-muted);
            font-size: 1.05rem;
            max-width: 600px;
            margin: 0 auto;
        }

        /* 下载卡片网格 */
        .download-grid {
            max-width: 1280px;
            margin: 0 auto 5rem;
            padding: 0 2rem;
            display: grid;
            grid-template-columns: repeat(2, 1fr);
            gap: 2.2rem;
        }
        .download-card {
            background: var(--bg-card);
            border: 1px solid var(--border-color);
            border-radius: var(--radius-xl);
            padding: 2.2rem;
            backdrop-filter: blur(12px);
            -webkit-backdrop-filter: blur(12px);
            transition: all var(--transition-smooth);
            display: flex;
            flex-direction: column;
            justify-content: space-between;
            position: relative;
            overflow: hidden;
        }
        .download-card::before {
            content: '';
            position: absolute;
            top: -20%;
            right: -15%;
            width: 200px;
            height: 200px;
            background: radial-gradient(circle, rgba(6, 182, 212, 0.08) 0%, transparent 70%);
            border-radius: 50%;
            pointer-events: none;
            transition: var(--transition-smooth);
        }
        .download-card:hover {
            border-color: var(--border-hover);
            transform: translateY(-6px);
            box-shadow: 0 24px 48px rgba(0, 0, 0, 0.45);
        }
        .download-card:hover::before {
            background: radial-gradient(circle, rgba(6, 182, 212, 0.15) 0%, transparent 70%);
        }
        .platform-header {
            display: flex;
            align-items: center;
            justify-content: space-between;
            margin-bottom: 1.2rem;
            flex-wrap: wrap;
            gap: 0.8rem;
        }
        .platform-info {
            display: flex;
            align-items: center;
            gap: 1rem;
        }
        .platform-icon {
            width: 52px;
            height: 52px;
            background: rgba(255,255,255,0.04);
            border-radius: var(--radius-md);
            display: flex;
            align-items: center;
            justify-content: center;
            border: 1px solid var(--border-color);
            color: var(--cyan);
            transition: var(--transition-smooth);
        }
        .download-card:hover .platform-icon {
            border-color: var(--border-cyan);
            box-shadow: 0 0 18px rgba(6, 182, 212, 0.2);
        }
        .platform-title h2 {
            font-size: 1.4rem;
            color: #fff;
            font-weight: 700;
        }
        .platform-title span {
            font-size: 0.8rem;
            color: var(--text-muted);
        }
        .version-badge {
            background: rgba(16, 185, 129, 0.1);
            color: var(--green);
            border: 1px solid rgba(16, 185, 129, 0.3);
            padding: 0.25rem 0.7rem;
            border-radius: 99px;
            font-size: 0.75rem;
            font-weight: 600;
        }
        .feature-list {
            list-style: none;
            margin: 1.2rem 0 1.8rem;
        }
        .feature-list li {
            color: var(--text-muted);
            font-size: 0.9rem;
            margin-bottom: 0.5rem;
            display: flex;
            align-items: center;
            gap: 0.5rem;
        }
        .feature-list li::before {
            content: "✓";
            color: var(--cyan);
            font-weight: bold;
        }
        .btn-download-group {
            display: flex;
            flex-direction: column;
            gap: 0.7rem;
        }
        .btn-download {
            background: linear-gradient(135deg, var(--cyan), var(--primary));
            color: #fff;
            padding: 0.9rem;
            border-radius: var(--radius-md);
            text-align: center;
            text-decoration: none;
            font-weight: 700;
            font-size: 0.95rem;
            display: flex;
            align-items: center;
            justify-content: center;
            gap: 0.5rem;
            box-shadow: 0 6px 20px rgba(6, 182, 212, 0.25);
            transition: all var(--transition-smooth);
        }
        .btn-download:hover {
            box-shadow: 0 12px 28px rgba(6, 182, 212, 0.5);
            transform: translateY(-2px);
        }
        .btn-sub {
            background: rgba(255,255,255,0.03);
            border: 1px solid var(--border-color);
            color: var(--text-main);
            padding: 0.7rem;
            border-radius: var(--radius-md);
            text-align: center;
            text-decoration: none;
            font-weight: 600;
            font-size: 0.85rem;
            transition: all var(--transition-smooth);
        }
        .btn-sub:hover {
            background: rgba(255,255,255,0.07);
            border-color: var(--border-hover);
        }

        /* 创意版块：官方正版安全保障 */
        .trust-banner {
            max-width: 1280px;
            margin: 0 auto 5rem;
            padding: 0 2rem;
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 2rem;
            align-items: center;
        }
        .trust-content h2 {
            font-size: 2rem;
            font-weight: 800;
            margin-bottom: 1rem;
            letter-spacing: -0.4px;
        }
        .trust-content p {
            color: var(--text-muted);
            font-size: 0.95rem;
            margin-bottom: 1.5rem;
            line-height: 1.7;
        }
        .trust-badges {
            display: flex;
            gap: 1rem;
            flex-wrap: wrap;
        }
        .trust-badge-item {
            background: rgba(16, 185, 129, 0.06);
            border: 1px solid rgba(16, 185, 129, 0.25);
            border-radius: var(--radius-md);
            padding: 0.7rem 1.2rem;
            display: flex;
            align-items: center;
            gap: 0.5rem;
            font-size: 0.9rem;
            color: var(--green);
            font-weight: 600;
        }
        .trust-visual {
            background: var(--bg-card-alt);
            border: 1px solid var(--border-color);
            border-radius: var(--radius-xl);
            padding: 2rem;
            text-align: center;
        }
        .trust-visual .cert-icon {
            font-size: 3.5rem;
            margin-bottom: 0.8rem;
        }
        .trust-visual .cert-text {
            color: var(--text-muted);
            font-size: 0.9rem;
        }

        /* 创意版块：跨平台无缝同步 */
        .sync-section {
            max-width: 1280px;
            margin: 0 auto 5rem;
            padding: 0 2rem;
        }
        .sync-grid {
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            gap: 1.5rem;
            text-align: center;
        }
        .sync-card {
            background: var(--bg-card);
            border: 1px solid var(--border-color);
            border-radius: var(--radius-lg);
            padding: 2rem 1rem;
            transition: var(--transition-smooth);
        }
        .sync-card:hover {
            border-color: var(--border-hover);
            transform: translateY(-4px);
        }
        .sync-icon {
            font-size: 2.2rem;
            margin-bottom: 0.8rem;
        }
        .sync-card h4 {
            font-size: 1rem;
            color: #fff;
            font-weight: 700;
            margin-bottom: 0.4rem;
        }
        .sync-card p {
            font-size: 0.8rem;
            color: var(--text-muted);
        }

        /* 创意版块：安装流程增强 */
        .install-guide-section {
            max-width: 1280px;
            margin: 0 auto 5rem;
            padding: 2.8rem;
            background: var(--bg-surface);
            border: 1px solid var(--border-color);
            border-radius: var(--radius-xl);
        }
        .install-guide-section h2 {
            font-size: 1.8rem;
            color: #fff;
            margin-bottom: 0.8rem;
            font-weight: 800;
        }
        .install-steps {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 2rem;
            margin-top: 2rem;
        }
        .step-item {
            background: rgba(255,255,255,0.02);
            padding: 1.8rem;
            border-radius: var(--radius-lg);
            border: 1px solid var(--border-color);
            transition: var(--transition-smooth);
        }
        .step-item:hover {
            border-color: var(--border-cyan);
            background: rgba(6, 182, 212, 0.03);
        }
        .step-num {
            font-size: 1.6rem;
            font-weight: 800;
            color: var(--cyan);
            margin-bottom: 0.5rem;
        }
        .step-item h3 {
            font-size: 1.1rem;
            color: #fff;
            margin-bottom: 0.5rem;
        }
        .step-item p {
            color: var(--text-muted);
            font-size: 0.88rem;
            line-height: 1.6;
        }

        /* Footer */
        footer {
            background: #03040a;
            border-top: 1px solid var(--border-color);
            padding: 4rem 2rem 2rem;
        }
        .footer-grid {
            max-width: 1280px;
            margin: 0 auto;
            display: grid;
            grid-template-columns: 2fr repeat(3, 1fr);
            gap: 3rem;
            margin-bottom: 3rem;
        }
        .footer-brand p {
            color: var(--text-muted);
            font-size: 0.88rem;
            margin-top: 1rem;
            max-width: 300px;
            line-height: 1.6;
        }
        .footer-col h4 {
            color: #fff;
            font-size: 0.95rem;
            margin-bottom: 1.1rem;
            font-weight: 700;
        }
        .footer-col ul { list-style: none; }
        .footer-col li { margin-bottom: 0.7rem; }
        .footer-col a {
            color: var(--text-muted);
            text-decoration: none;
            font-size: 0.88rem;
            transition: color var(--transition-fast);
        }
        .footer-col a:hover { color: #fff; }
        .footer-bottom {
            max-width: 1280px;
            margin: 0 auto;
            padding-top: 2rem;
            border-top: 1px solid rgba(255,255,255,0.04);
            display: flex;
            justify-content: space-between;
            color: var(--text-muted);
            font-size: 0.82rem;
            flex-wrap: wrap;
            gap: 1rem;
        }

        /* 响应式 */
        @media (max-width: 992px) {
            .download-grid { grid-template-columns: 1fr; }
            .trust-banner { grid-template-columns: 1fr; }
            .sync-grid { grid-template-columns: repeat(2, 1fr); }
            .install-steps { grid-template-columns: 1fr; }
            .footer-grid { grid-template-columns: 1fr 1fr; }
        }
        @media (max-width: 600px) {
            .sync-grid { grid-template-columns: 1fr; }
            .footer-grid { grid-template-columns: 1fr; }
        }