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

        body {
            font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
            line-height: 1.6;
            color: #333;
            background: #fff;
        }

        .j990-header {
            position: fixed;
            top: 0;
            left: 0;
            right: 0;
            background: rgba(255, 255, 255, 0.95);
            backdrop-filter: blur(10px);
            border-bottom: 1px solid rgba(0, 0, 0, 0.1);
            z-index: 1000;
            transition: all 0.3s ease;
        }

        .j990-nav {
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 20px;
            display: flex;
            align-items: center;
            justify-content: space-between;
            height: 70px;
        }

        .j990-logo img {
            height: 40px;
            width: auto;
        }

        .j990-menu-toggle {
            display: none;
            flex-direction: column;
            background: none;
            border: none;
            cursor: pointer;
            padding: 5px;
        }

        .j990-menu-toggle span {
            width: 25px;
            height: 3px;
            background: #333;
            margin: 3px 0;
            transition: 0.3s;
        }

        .j990-nav-menu {
            display: flex;
            list-style: none;
            gap: 30px;
        }

        .j990-nav-menu a {
            text-decoration: none;
            color: #333;
            font-weight: 500;
            transition: color 0.3s ease;
            position: relative;
        }

        .j990-nav-menu a:hover {
            color: #007bff;
        }

        .j990-nav-menu a.active {
            color: #007bff;
        }

        .j990-nav-menu a.active::after {
            content: '';
            position: absolute;
            bottom: -5px;
            left: 0;
            right: 0;
            height: 2px;
            background: #007bff;
        }

        .j990-nav-overlay {
            display: none;
            position: fixed;
            top: 0;
            left: 0;
            right: 0;
            bottom: 0;
            background: rgba(0, 0, 0, 0.5);
            z-index: 999;
        }

        .j990-hero-section {
            background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
            color: white;
            padding: 120px 0 80px;
            text-align: center;
            position: relative;
            overflow: hidden;
        }

        .j990-hero-section::before {
            content: '';
            position: absolute;
            top: 0;
            left: 0;
            right: 0;
            bottom: 0;
            background: url('images/features.jpg') center/cover;
            opacity: 0.2;
            z-index: 1;
        }

        .j990-hero-content {
            position: relative;
            z-index: 2;
            max-width: 800px;
            margin: 0 auto;
            padding: 0 20px;
        }

        .j990-hero-title {
            font-size: 3.5rem;
            font-weight: 700;
            margin-bottom: 20px;
            background: linear-gradient(45deg, #fff, #e0e7ff);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
        }

        .j990-hero-subtitle {
            font-size: 1.3rem;
            opacity: 0.9;
            margin-bottom: 40px;
            line-height: 1.8;
        }

        .j990-features-grid {
            max-width: 1200px;
            margin: -60px auto 0;
            padding: 0 20px;
            position: relative;
            z-index: 3;
        }

        .j990-features-container {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
            gap: 30px;
        }

        .j990-feature-card {
            background: white;
            border-radius: 20px;
            padding: 40px 30px;
            box-shadow: 0 20px 40px rgba(0, 0, 0, 0.1);
            transition: all 0.3s ease;
            border: 1px solid rgba(0, 0, 0, 0.05);
            position: relative;
            overflow: hidden;
        }

        .j990-feature-card::before {
            content: '';
            position: absolute;
            top: 0;
            left: 0;
            right: 0;
            height: 4px;
            background: linear-gradient(90deg, #007bff, #00d4ff);
            transform: scaleX(0);
            transition: transform 0.3s ease;
        }

        .j990-feature-card:hover {
            transform: translateY(-10px);
            box-shadow: 0 30px 60px rgba(0, 0, 0, 0.15);
        }

        .j990-feature-card:hover::before {
            transform: scaleX(1);
        }

        .j990-feature-icon {
            font-size: 3rem;
            margin-bottom: 20px;
            display: block;
        }

        .j990-feature-title {
            font-size: 1.5rem;
            font-weight: 600;
            margin-bottom: 15px;
            color: #333;
        }

        .j990-feature-desc {
            color: #666;
            line-height: 1.7;
            font-size: 1rem;
        }

        .j990-tech-section {
            padding: 100px 0;
            background: linear-gradient(135deg, #f8faff 0%, #e8f2ff 100%);
        }

        .j990-container {
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 20px;
        }

        .j990-section-title {
            text-align: center;
            font-size: 2.5rem;
            font-weight: 700;
            margin-bottom: 20px;
            color: #333;
        }

        .j990-section-subtitle {
            text-align: center;
            font-size: 1.2rem;
            color: #666;
            margin-bottom: 60px;
            max-width: 600px;
            margin-left: auto;
            margin-right: auto;
        }

        .j990-tech-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
            gap: 40px;
            margin-top: 60px;
        }

        .j990-tech-card {
            background: white;
            border-radius: 15px;
            padding: 35px;
            box-shadow: 0 10px 30px rgba(0, 0, 0, 0.08);
            transition: all 0.3s ease;
            border-left: 4px solid #007bff;
        }

        .j990-tech-card:hover {
            transform: translateY(-5px);
            box-shadow: 0 20px 40px rgba(0, 0, 0, 0.12);
        }

        .j990-tech-title {
            font-size: 1.4rem;
            font-weight: 600;
            margin-bottom: 15px;
            color: #333;
        }

        .j990-tech-desc {
            color: #666;
            line-height: 1.7;
        }

        .j990-stats-section {
            padding: 80px 0;
            background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
            color: white;
            text-align: center;
        }

        .j990-stats-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
            gap: 40px;
            margin-top: 50px;
        }

        .j990-stat-item {
            padding: 20px;
        }

        .j990-stat-number {
            font-size: 3rem;
            font-weight: 700;
            margin-bottom: 10px;
            display: block;
        }

        .j990-stat-label {
            font-size: 1.1rem;
            opacity: 0.9;
        }

        .j990-scenarios-section {
            padding: 100px 0;
            background: white;
        }

        .j990-scenarios-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
            gap: 30px;
            margin-top: 60px;
        }

        .j990-scenario-card {
            text-align: center;
            padding: 40px 30px;
            border-radius: 15px;
            background: #f8faff;
            transition: all 0.3s ease;
            border: 2px solid transparent;
        }

        .j990-scenario-card:hover {
            background: white;
            border-color: #007bff;
            transform: translateY(-5px);
            box-shadow: 0 15px 35px rgba(0, 0, 0, 0.1);
        }

        .j990-scenario-icon {
            font-size: 3rem;
            margin-bottom: 20px;
            display: block;
        }

        .j990-scenario-title {
            font-size: 1.4rem;
            font-weight: 600;
            margin-bottom: 15px;
            color: #333;
        }

        .j990-scenario-desc {
            color: #666;
            line-height: 1.7;
        }

        .j990-products-section {
            padding: 100px 0;
            background: linear-gradient(135deg, #f8faff 0%, #e8f2ff 100%);
        }

        .j990-products-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
            gap: 40px;
            margin-top: 60px;
        }

        .j990-product-card {
            background: white;
            border-radius: 20px;
            padding: 40px;
            box-shadow: 0 15px 35px rgba(0, 0, 0, 0.08);
            transition: all 0.3s ease;
            position: relative;
            overflow: hidden;
        }

        .j990-product-card::before {
            content: '';
            position: absolute;
            top: 0;
            left: 0;
            right: 0;
            height: 5px;
            background: linear-gradient(90deg, #007bff, #00d4ff);
        }

        .j990-product-card:hover {
            transform: translateY(-10px);
            box-shadow: 0 25px 50px rgba(0, 0, 0, 0.15);
        }

        .j990-product-name {
            font-size: 1.6rem;
            font-weight: 700;
            margin-bottom: 15px;
            color: #333;
        }

        .j990-product-desc {
            color: #666;
            line-height: 1.7;
            margin-bottom: 20px;
        }

        .j990-product-highlight {
            display: inline-block;
            background: linear-gradient(135deg, #007bff, #00d4ff);
            color: white;
            padding: 8px 16px;
            border-radius: 20px;
            font-size: 0.9rem;
            font-weight: 500;
            margin-right: 10px;
            margin-bottom: 10px;
        }

        .j990-footer {
            background: #1a1a1a;
            color: white;
            padding: 60px 0 30px;
        }

        .j990-footer-content {
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 20px;
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
            gap: 40px;
        }

        .j990-footer-section h3 {
            font-size: 1.3rem;
            margin-bottom: 20px;
            color: #fff;
        }

        .j990-footer-section p,
        .j990-footer-section a {
            color: #ccc;
            text-decoration: none;
            line-height: 1.8;
            transition: color 0.3s ease;
        }

        .j990-footer-section a:hover {
            color: #007bff;
        }

        .j990-footer-bottom {
            border-top: 1px solid #333;
            margin-top: 40px;
            padding-top: 20px;
            text-align: center;
            color: #999;
        }

        @media (max-width: 768px) {
            .j990-menu-toggle {
                display: flex;
            }

            .j990-nav-menu {
                display: none;
                position: fixed;
                top: 70px;
                left: 0;
                right: 0;
                background: white;
                flex-direction: column;
                padding: 20px;
                box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
                gap: 15px;
            }

            .j990-nav-menu.active {
                display: flex;
            }

            .j990-hero-title {
                font-size: 2.5rem;
            }

            .j990-hero-subtitle {
                font-size: 1.1rem;
            }

            .j990-features-container {
                grid-template-columns: 1fr;
                gap: 20px;
            }

            .j990-feature-card {
                padding: 30px 25px;
            }

            .j990-section-title {
                font-size: 2rem;
            }

            .j990-stats-grid {
                grid-template-columns: repeat(2, 1fr);
                gap: 30px;
            }

            .j990-stat-number {
                font-size: 2.5rem;
            }

            .j990-scenarios-grid,
            .j990-products-grid,
            .j990-tech-grid {
                grid-template-columns: 1fr;
                gap: 20px;
            }
        }

        @media (max-width: 480px) {
            .j990-hero-title {
                font-size: 2rem;
            }

            .j990-feature-card,
            .j990-scenario-card,
            .j990-product-card {
                padding: 25px 20px;
            }

            .j990-stats-grid {
                grid-template-columns: 1fr;
            }
        }