* {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }

        :root {
            --text: #111827;
            --text-secondary: #6B7280;
            --text-light: #9CA3AF;
            --accent: #6366F1;
            --accent-light: #818CF8;
            --accent-dark: #4F46E5;
            --bg: #FFFFFF;
            --bg-secondary: #F9FAFB;
            --bg-tertiary: #F3F4F6;
            --border: #E5E7EB;
            --gradient-primary: linear-gradient(135deg, #6366F1 0%, #8B5CF6 50%, #EC4899 100%);
            --gradient-hero: linear-gradient(135deg, #6366F1 0%, #8B5CF6 100%);
        }

        html { scroll-behavior: smooth; }

        body {
            font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
            color: var(--text);
            line-height: 1.6;
            overflow-x: hidden;
            background: var(--bg);
        }

        h1, h2, h3, h4 {
            font-weight: 700;
            line-height: 1.2;
            letter-spacing: -0.02em;
        }

        .container {
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 24px;
        }

        /* Navigation */
        .navbar {
            position: fixed;
            top: 0;
            left: 0;
            right: 0;
            z-index: 1000;
            background: rgba(255, 255, 255, 0.9);
            backdrop-filter: blur(12px);
            border-bottom: 1px solid var(--border);
        }

        .navbar .container {
            display: flex;
            justify-content: space-between;
            align-items: center;
            height: 72px;
        }

        .logo {
            font-size: 20px;
            font-weight: 700;
            color: var(--text);
            text-decoration: none;
            display: flex;
            align-items: center;
            gap: 10px;
        }

        .logo-text {
            background: var(--gradient-primary);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
        }

        .logo-icon {
            width: 32px;
            height: 32px;
            border-radius: 8px;
            object-fit: contain;
        }

        .nav-links {
            display: flex;
            gap: 32px;
            list-style: none;
        }

        .nav-links a {
            color: var(--text-secondary);
            text-decoration: none;
            font-weight: 500;
            font-size: 14px;
            transition: color 0.2s;
            cursor: pointer;
        }

        .nav-links a:hover { color: var(--text); }
        .nav-links a.active { color: var(--accent); font-weight: 600; }

        .nav-cta { display: flex; gap: 12px; }

        .btn {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            padding: 10px 20px;
            border-radius: 8px;
            font-weight: 600;
            font-size: 14px;
            text-decoration: none;
            transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
            cursor: pointer;
            border: none;
        }

        .btn-ghost {
            background: transparent;
            color: var(--text);
        }

        .btn-ghost:hover { background: var(--bg-tertiary); }

        .btn-primary {
            background: var(--gradient-primary);
            color: white;
            border: none;
        }

        .btn-primary:hover {
            box-shadow: 0 8px 24px rgba(99, 102, 241, 0.4);
            transform: translateY(-2px);
        }

        /* Download Hero */
        .download-hero {
            padding: 160px 0 100px;
            background: var(--bg);
            position: relative;
            overflow: hidden;
        }

        .download-hero::before {
            content: '';
            position: absolute;
            top: -50%;
            right: -20%;
            width: 800px;
            height: 800px;
            background: radial-gradient(circle, rgba(99, 102, 241, 0.08) 0%, transparent 70%);
            pointer-events: none;
        }

        .download-hero::after {
            content: '';
            position: absolute;
            bottom: -30%;
            left: -10%;
            width: 600px;
            height: 600px;
            background: radial-gradient(circle, rgba(139, 92, 246, 0.06) 0%, transparent 70%);
            pointer-events: none;
        }

        .download-hero .container {
            position: relative;
            z-index: 1;
        }

        .download-hero h1 {
            font-size: 48px;
            font-weight: 800;
            color: var(--text);
            margin-bottom: 16px;
            text-align: center;
        }

        .download-hero h1 .highlight {
            background: var(--gradient-primary);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
        }

        .download-hero-desc {
            font-size: 18px;
            color: var(--text-secondary);
            margin-bottom: 48px;
            max-width: 500px;
            text-align: center;
            margin-left: auto;
            margin-right: auto;
        }

        /* Download Content */
        .download-content {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 32px;
            align-items: stretch;
        }

        /* Download Card */
        .download-card {
            background: var(--bg);
            border-radius: 24px;
            padding: 40px;
            border: 1px solid var(--border);
            box-shadow: 0 20px 60px rgba(99, 102, 241, 0.1);
            transition: all 0.3s ease;
            display: flex;
            flex-direction: column;
        }

        .download-card:hover {
            box-shadow: 0 30px 80px rgba(99, 102, 241, 0.15);
        }

        .download-card .download-btn-main {
            margin-top: auto;
        }

        .download-platform {
            display: flex;
            align-items: center;
            gap: 16px;
            margin-bottom: 24px;
        }

        .platform-icon-large {
            width: 64px;
            height: 64px;
            background: linear-gradient(135deg, #0078D4 0%, #00BCF2 100%);
            border-radius: 16px;
            display: flex;
            align-items: center;
            justify-content: center;
        }

        .platform-icon-large svg {
            width: 32px;
            height: 32px;
            color: white;
        }

        .download-platform-info h3 {
            font-size: 24px;
            color: var(--text);
            margin-bottom: 4px;
        }

        .download-platform-info p {
            font-size: 14px;
            color: var(--text-secondary);
        }

        .download-version {
            display: flex;
            justify-content: space-between;
            padding: 16px 20px;
            background: var(--bg-secondary);
            border-radius: 12px;
            margin-bottom: 24px;
        }

        .version-item {
            text-align: center;
        }

        .version-item span {
            font-size: 12px;
            color: var(--text-light);
            display: block;
            margin-bottom: 4px;
        }

        .version-item strong {
            font-size: 14px;
            color: var(--text);
        }

        .download-btn-main {
            width: 100%;
            padding: 18px 32px;
            font-size: 16px;
            font-weight: 600;
            background: var(--gradient-primary);
            color: white;
            border-radius: 12px;
            display: flex;
            align-items: center;
            justify-content: center;
            gap: 12px;
            cursor: pointer;
            transition: all 0.3s ease;
            text-decoration: none;
        }

        .download-btn-main:hover {
            box-shadow: 0 12px 32px rgba(99, 102, 241, 0.4);
            transform: translateY(-4px);
        }

        .download-btn-main svg {
            width: 20px;
            height: 20px;
        }

        .download-note {
            margin-top: 16px;
            font-size: 13px;
            color: var(--text-light);
            text-align: center;
        }

        /* Requirements Card */
        .requirements-card {
            background: var(--bg);
            border-radius: 24px;
            padding: 40px;
            border: 1px solid var(--border);
            box-shadow: 0 20px 60px rgba(99, 102, 241, 0.1);
            transition: all 0.3s ease;
            display: flex;
            flex-direction: column;
        }

        .requirements-card:hover {
            box-shadow: 0 30px 80px rgba(99, 102, 241, 0.15);
        }

        .requirements-card h2 {
            font-size: 24px;
            color: var(--text);
            margin-bottom: 24px;
        }

        .requirements-list {
            flex: 1;
            display: flex;
            flex-direction: column;
        }

        .requirement-item {
            display: flex;
            align-items: flex-start;
            gap: 16px;
            padding: 16px 0;
            border-bottom: 1px solid var(--border);
        }

        .requirement-item:last-child {
            border-bottom: none;
        }

        .requirement-icon {
            width: 40px;
            height: 40px;
            background: linear-gradient(135deg, rgba(99, 102, 241, 0.1) 0%, rgba(139, 92, 246, 0.1) 100%);
            border-radius: 10px;
            display: flex;
            align-items: center;
            justify-content: center;
            flex-shrink: 0;
        }

        .requirement-icon svg {
            width: 20px;
            height: 20px;
            color: var(--accent);
        }

        .requirement-info h4 {
            font-size: 15px;
            color: var(--text);
            margin-bottom: 4px;
        }

        .requirement-info p {
            font-size: 13px;
            color: var(--text-secondary);
            line-height: 1.5;
        }

        .download-tip {
            display: flex;
            align-items: center;
            gap: 8px;
            padding: 12px 16px;
            background: linear-gradient(135deg, rgba(99, 102, 241, 0.08) 0%, rgba(139, 92, 246, 0.08) 100%);
            border-radius: 12px;
            margin: 24px 0;
            font-size: 13px;
            color: #6366f1;
            border: 1px solid rgba(99, 102, 241, 0.15);
        }

        .download-tip svg {
            flex-shrink: 0;
        }

        /* FAQ Section */
        .faq {
            padding: 80px 0;
            background: var(--bg-secondary);
        }

        .faq h2 {
            font-size: 32px;
            color: var(--text);
            margin-bottom: 48px;
            text-align: center;
        }

        .faq-grid {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 24px;
            max-width: 1000px;
            margin: 0 auto;
        }

        .faq-item {
            background: var(--bg);
            border-radius: 12px;
            padding: 24px;
            border: 1px solid var(--border);
            transition: all 0.3s ease;
        }

        .faq-item:hover {
            border-color: var(--accent-light);
            box-shadow: 0 8px 24px rgba(99, 102, 241, 0.08);
        }

        .faq-item h4 {
            font-size: 16px;
            color: var(--text);
            margin-bottom: 8px;
        }

        .faq-item p {
            font-size: 14px;
            color: var(--text-secondary);
            line-height: 1.6;
        }

        /* Footer */
        .footer {
            padding: 64px 0 32px;
            background: var(--bg);
            border-top: 1px solid var(--border);
        }

        .footer-grid {
            display: grid;
            grid-template-columns: 2fr 1fr 1fr 1fr;
            gap: 48px;
            margin-bottom: 48px;
        }

        .footer-brand .logo {
            margin-bottom: 16px;
        }

        .footer-brand p {
            font-size: 14px;
            color: var(--text-secondary);
            line-height: 1.7;
        }

        .footer-column h4 {
            color: var(--text);
            font-size: 14px;
            font-weight: 600;
            margin-bottom: 20px;
        }

        .footer-links {
            list-style: none;
        }

        .footer-links li { margin-bottom: 12px; }

        .footer-links a {
            color: var(--text-secondary);
            text-decoration: none;
            font-size: 14px;
            transition: color 0.2s;
            cursor: pointer;
        }

        .footer-links a:hover { color: var(--text); }

        .footer-bottom {
            padding-top: 32px;
            border-top: 1px solid var(--border);
            display: flex;
            justify-content: space-between;
            align-items: center;
            font-size: 13px;
            color: var(--text-light);
        }

        .footer-bottom-links {
            display: flex;
            gap: 24px;
        }

        .footer-bottom-links a {
            color: var(--text-light);
            text-decoration: none;
            cursor: pointer;
            transition: color 0.2s;
        }

        .footer-bottom-links a:hover { color: var(--text); }

        /* Responsive */
        @media (max-width: 1024px) {
            .download-content { grid-template-columns: 1fr; }
            .footer-grid { grid-template-columns: 1fr 1fr; }
        }

        @media (max-width: 768px) {
            .navbar .container { height: 64px; }
            .nav-links { display: none; }
            .download-hero { padding: 120px 0 80px; }
            .download-hero h1 { font-size: 36px; }
            .download-card, .requirements-card { padding: 32px 24px; }
            .faq-grid { grid-template-columns: 1fr; }
            .footer-grid { grid-template-columns: 1fr; gap: 32px; }
            .footer-bottom { flex-direction: column; gap: 16px; text-align: center; }
        }

        /* 模态框样式 */
        .modal-overlay {
            display: none;
            position: fixed;
            top: 0; left: 0; right: 0; bottom: 0;
            background: rgba(0, 0, 0, 0.6);
            z-index: 2000;
            justify-content: center;
            align-items: center;
            padding: 20px;
        }
        .modal-overlay.active { display: flex; }
        .modal-content {
            background: var(--bg);
            border-radius: 16px;
            max-width: 800px; width: 100%;
            max-height: 80vh;
            overflow: hidden;
            position: relative;
            box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
            display: flex;
            flex-direction: column;
        }
        .modal-header {
            display: flex;
            justify-content: space-between;
            align-items: center;
            padding: 24px 32px;
            border-bottom: 1px solid var(--border);
            flex-shrink: 0;
        }
        .modal-header h2 { font-size: 24px; color: var(--text); }
        .modal-close {
            width: 32px; height: 32px;
            border-radius: 8px;
            background: var(--bg-tertiary);
            border: none; cursor: pointer;
            display: flex; align-items: center; justify-content: center;
        }
        .modal-close:hover { background: var(--border); }
        .modal-close svg { width: 16px; height: 16px; color: var(--text-secondary); }
        .modal-body { padding: 32px; line-height: 1.8; overflow-y: auto; flex: 1; }
        .modal-body h3 { font-size: 18px; color: var(--text); margin: 24px 0 12px 0; }
        .modal-body h3:first-child { margin-top: 0; }
        .modal-body p { color: var(--text-secondary); margin-bottom: 16px; }
        .modal-body ul { color: var(--text-secondary); margin-bottom: 16px; padding-left: 20px; }
        .modal-body li { margin-bottom: 8px; }
        @media (max-width: 768px) {
            .modal-content { max-height: 90vh; }
            .modal-header { padding: 16px 20px; }
            .modal-body { padding: 20px; }
        }