/* 全局样式设定 */
        

        

        :root {
            --primary: #0F52BA; /* 科技蓝 */
            --primary-dark: #0B3A82;
            --accent: #EF4444; /* 行动橙 */
            --slate-800: #1e293b;
            --slate-100: #f1f5f9;
        }

        .container {
            width: 90%;
            max-width: 1200px;
            margin: 0 auto;
        }

        /* 固定的头部 */
        

        

        

        

        /* 1. 首屏营销 Banner */
        .hero {
            background: linear-gradient(180deg, #131e2e 0%, #0b1320 100%);
            color: #fff;
            padding: 220px 0 110px 0; /* Adjusted for header */
            text-align: center;
        }

        .hero h1 {
            font-size: 46px;
            margin-bottom: 25px;
            font-weight: 700;
            letter-spacing: 1px;
        }

        .hero h1 span {
            color: #38bdf8;
        }

        .hero p {
            font-size: 18px;
            color: #94a3b8;
            margin-bottom: 40px;
            max-width: 850px;
            margin-left: auto;
            margin-right: auto;
            font-weight: 300;
        }

        .btn-cta {
            display: inline-block;
            background-color: #0F52BA;
            color: #fff;
            padding: 14px 45px;
            font-size: 18px;
            font-weight: bold;
            text-decoration: none;
            border-radius: 4px;
            box-shadow: 0 4px 14px rgba(2, 132, 199, 0.4);
            transition: all 0.3s;
        }

        .btn-cta:hover {
            background-color: var(--primary-dark);
            transform: translateY(-2px);
        }

        /* 通用区块标题样式 */
        .section-title {
            text-align: center;
            font-size: 28px;
            margin-bottom: 45px;
            color: var(--slate-800);
            position: relative;
            font-weight: 700;
        }

        .section-title::after {
            content: '';
            display: block;
            width: 40px;
            height: 3px;
            background-color: #0F52BA;
            margin: 12px auto 0 auto;
            border-radius: 2px;
        }

        .section-padding {
            padding: 70px 0;
        }

        .bg-white { background-color: #fff; }
        .bg-gray { background-color: var(--slate-100); }

        /* 2. 广泛应用于各前沿科技测试场景样式 */
        .usecase-container {
            display: flex;
            flex-direction: column;
            gap: 30px;
        }

        .usecase-row {
            display: flex;
            align-items: center;
            gap: 40px;
            background: #fff;
            padding: 30px;
            border-radius: 6px;
            box-shadow: 0 4px 15px rgba(0,0,0,0.02);
        }

        .usecase-img {
            box-shadow: 0 10px 15px -3px rgba(0,0,0,0.05);
            flex: 1;
            height: 240px;
            background-color: #cbd5e1;
            border-radius: 6px;
            overflow: hidden;
        }

        .usecase-img img {
            width: 100%;
            height: 100%;
            object-fit: cover;
        }

        .usecase-info {
            flex: 1.3;
        }

        .usecase-info h3 {
            font-size: 20px;
            color: #0F52BA;
            margin-bottom: 15px;
            font-weight: 700;
        }

        .usecase-info p {
            font-size: 14px;
            color: #64748b;
            margin-bottom: 15px;
        }

        .usecase-info ul {
            list-style-type: none;
        }

        .usecase-info ul li {
            position: relative;
            padding-left: 20px;
            margin-bottom: 8px;
            color: #475569;
            font-size: 14px;
        }

        .usecase-info ul li::before {
            content: "■";
            color: #0F52BA;
            font-size: 10px;
            position: absolute;
            left: 0;
            top: 1px;
        }

        /* 3. 如何选择和确定合适的屏蔽箱样式 */
        .guide-steps {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
            gap: 25px;
        }

        .step-card {
            background-color: #fff;
            padding: 30px 20px;
            border-radius: 6px;
            box-shadow: 0 4px 15px rgba(0,0,0,0.02);
            text-align: center;
            border-top: 4px solid #0F52BA;
        }

        .step-num {
            font-size: 38px;
            font-weight: 800;
            color: #e2e8f0;
            line-height: 1;
            margin-bottom: 15px;
        }

        .step-card h4 {
            font-size: 16px;
            margin-bottom: 12px;
            color: var(--slate-800);
            font-weight: 700;
        }

        .step-card p {
            font-size: 13px;
            color: #64748b;
            text-align: left;
            line-height: 1.6;
        }

        /* 4. 精工制造，打磨三大核心性能特点样式 */
        .features-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
            gap: 25px;
        }

        .feature-card {
            background: #fff;
            border-radius: 6px;
            overflow: hidden;
            box-shadow: 0 4px 15px rgba(0,0,0,0.03);
            border: 1px solid #e2e8f0;
        }

        .feature-img-box {
            height: 200px;
            background-color: #cbd5e1;
            display: flex;
            align-items: center;
            justify-content: center;
            overflow: hidden;
        }
        
        .feature-img-box img {
            width: 100%;
            height: 100%;
            object-fit: cover;
        }

        .feature-content {
            padding: 25px;
        }

        .feature-content h3 {
            font-size: 18px;
            margin-bottom: 12px;
            color: var(--slate-800);
            font-weight: 700;
        }

        .feature-content p {
            font-size: 14px;
            color: #64748b;
        }

        /* 5. 核心拳头产品展示 (优化：主图左右交错，且均具备点击展开子功能) */
        .product-showcase {
            padding: 80px 0;
        }

        .prod-row {
            display: flex;
            align-items: center;
            gap: 50px;
            margin-bottom: 30px;
        }

        /* 实现左右视觉交错排布 */
        .prod-row.left-img {
            flex-direction: row-reverse;
        }

        .prod-img {
            flex: 1;
            border-radius: 8px;
            overflow: hidden;
            box-shadow: 0 10px 20px rgba(0,0,0,0.08);
            height: 350px;
            transition: border-color 0.2s;
        }

        .prod-img img {
            width: 100%;
            height: 100%;
            object-fit: cover;
        }

        .prod-details {
            flex: 1;
        }

        .prod-details h3 {
            font-size: 24px;
            color: #1e293b;
            margin-bottom: 15px;
            font-weight: 700;
        }

        .prod-details .subtitle {
            font-size: 15px;
            color: #64748b;
            margin-bottom: 25px;
            line-height: 1.6;
        }

        .prod-details ul {
            list-style: none;
            margin-bottom: 30px;
        }

        .prod-details ul li {
            font-size: 15px;
            color: #334155;
            margin-bottom: 12px;
            padding-left: 25px;
            position: relative;
        }

        .prod-details ul li::before {
            content: '✓';
            color: #10b981;
            font-weight: bold;
            position: absolute;
            left: 0;
            top: 0;
        }

        .btn-prod-cta {
            display: inline-block;
            background-color: #0F52BA;
            color: #fff;
            padding: 12px 30px;
            font-size: 16px;
            font-weight: bold;
            text-decoration: none;
            border-radius: 4px;
            transition: background-color 0.2s;
        }

        .btn-prod-cta:hover {
            background-color: #0B3A82;
        }

        /* 2行3列 专属子网格容器 */
        .sub-grid-container {
            display: grid;
            grid-template-columns: repeat(3, 1fr); 
            gap: 25px;
            margin-top: 30px;
            margin-bottom: 50px;
            animation: dropdownFadeIn 0.5s ease both;
        }

        .sub-prod-card {
            background: #fff; 
            border-radius: 8px; 
            overflow: hidden; 
            box-shadow: 0 10px 15px -3px rgba(0,0,0,0.04); 
            text-align: center; 
            padding-bottom: 20px;
            border: 1px solid #e2e8f0;
            text-decoration: none;
            color: inherit;
            display: block;
            transition: transform 0.3s ease, box-shadow 0.3s ease;
        }

        .sub-prod-card:hover {
            transform: translateY(-6px);
            box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.08);
        }

        .sub-img-wrapper {
            height: 190px; 
            background: #e2e8f0; 
            overflow: hidden;
        }

        .sub-img-wrapper img {
            width: 100%; 
            height: 100%; 
            object-fit: cover;
        }

        .sub-prod-card h4 {
            font-size: 16px; 
            margin-top: 15px; 
            font-weight: 700;
            color: #1e293b;
        }

        @keyframes dropdownFadeIn {
            from { opacity: 0; transform: translateY(15px); }
            to { opacity: 1; transform: translateY(0); }
        }

        /* 6. 为什么选择我们的定制服务？ */
        .custom-services-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
            gap: 25px;
            margin-top: 30px;
        }

        .custom-card {
            background: #f1f5f9;
            padding: 40px 25px;
            border-radius: 8px;
            text-align: center;
            transition: transform 0.3s, box-shadow 0.3s;
        }

        .custom-card:hover {
            transform: translateY(-3px);
            box-shadow: 0 10px 20px rgba(0,0,0,0.05);
        }

        .custom-card h3 {
            font-size: 20px;
            color: #1e293b;
            margin: 15px 0 12px 0;
            font-weight: 700;
        }

        .custom-card p {
            font-size: 15px;
            color: #475569;
            line-height: 1.7;
        }

        .strength-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
            gap: 20px;
            margin-top: 30px;
        }

        .strength-card {
            background: #fff;
            padding: 35px 22px;
            border-radius: 6px;
            text-align: center;
            box-shadow: 0 10px 25px -5px rgba(0,0,0,0.05);
            border-bottom: 3px solid #0F52BA;
            transition: transform 0.3s;
        }

        .strength-card:hover {
            transform: translateY(-5px);
        }

        .strength-card h4 {
            font-size: 18px;
            color: var(--slate-800);
            margin-bottom: 15px;
            font-weight: 700;
        }

        .strength-card p {
            font-size: 14px;
            color: #64748b;
            text-align: left;
        }

        /* 留资表单 */
        .form-section {
            background-color: var(--slate-800);
            color: #fff;
        }

        .form-wrapper {
            max-width: 650px;
            margin: 0 auto;
            background: rgba(255,255,255,0.04);
            padding: 40px;
            border-radius: 8px;
            border: 1px solid rgba(255,255,255,0.08);
        }

        .form-row {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 20px;
            margin-bottom: 20px;
        }

        .form-group {
            margin-bottom: 20px;
        }

        .form-group label {
            display: block;
            font-size: 14px;
            color: #cbd5e1;
            margin-bottom: 8px;
        }

        .form-group input, .form-group select, .form-group textarea {
            width: 100%;
            padding: 12px;
            background-color: #0f172a;
            border: 1px solid #475569;
            color: #fff;
            border-radius: 4px;
            font-size: 15px;
        }

        .form-group input:focus, .form-group select:focus, .form-group textarea:focus {
            outline: none;
            border-color: #38bdf8;
        }

        .btn-submit {
            width: 100%;
            background-color: #0F52BA;
            color: #fff;
            padding: 15px;
            border: none;
            border-radius: 4px;
            font-size: 18px;
            font-weight: bold;
            cursor: pointer;
            transition: background 0.3s;
        }

        .btn-submit:hover {
            background-color: #0B3A82;
        }

        

        @media (max-width: 768px) {
            .hero h1 { font-size: 32px; }
            .usecase-row { flex-direction: column; padding: 20px; }
            .prod-row, .prod-row.left-img { flex-direction: column; gap: 30px; }
            .sub-grid-container { grid-template-columns: repeat(2, 1fr); } 
            .form-row { grid-template-columns: 1fr; gap: 0; }
            
            .hero { padding: 190px 0 60px 0; }
        }

        @media (max-width: 480px) {
            .sub-grid-container { grid-template-columns: 1fr; } 
        }