/* roulang page: index */
<img>` tag includes a descriptive `alt` attribute, referencing "模拟芯片" or related terms. Content will be reviewed to eliminate prohibited terminology and structural phrases. Meta description length needs verification against the specified character count.


The provided code snippet resides within a `<style>` block, necessitating its closure before adding `<head>`, `<body>`, and other HTML elements.  The continuation begins immediately with the FAQ section's CSS. This includes styling for the FAQ container, list, individual items, and the active state.


Styling the FAQ section involves defining container layout, managing answer visibility through maximum height transitions, and incorporating visual feedback for active states via icon rotation. The `#sample-form` requires styling for its container, including background, border, shadow, padding, and a grid layout for its content.


Footer styling will involve setting background color, text color, padding, and a top border. Media queries will be defined for responsiveness across different screen sizes. The `<style>` tag will be closed, followed by the `<head>` section's closing tag, and the `<body>` will be initiated. A double-row top navigation will be structured, including a top bar and main navigation with links to various sections.


Analyzing the provided sections reveals the core technical narrative focuses on high-precision analog signal chain chips and high-speed interface isolation chips. Benchmarking against competitors will involve comparisons across several metrics. The architecture section showcases noise isolation techniques and self-calibration algorithms.

Milestones highlight the product's development, including in-house op-amp design and successful testing. Case studies demonstrate the chips' application in various systems. High yield statistics and engineer reviews support the quality claims. The final sections cover news, quality assurance, FAQs, and a sample request form.


section) */
        .faq-container {
            max-width: 860px;
            margin: 0 auto;
            display: flex;
            flex-direction: column;
            gap: 16px;
        }

        .faq-item {
            background: #ffffff;
            border-radius: 18px;
            border: 1px solid var(--border-color);
            overflow: hidden;
            transition: all 0.25s ease;
            box-shadow: var(--shadow-sm);
        }

        .faq-item.active {
            border-color: var(--primary);
            box-shadow: var(--shadow-card);
        }

        .faq-trigger {
            width: 100%;
            padding: 22px 28px;
            text-align: left;
            background: none;
            border: none;
            display: flex;
            justify-content: space-between;
            align-items: center;
            font-size: 1.05rem;
            font-weight: 700;
            color: var(--dark-graphite);
            cursor: pointer;
            gap: 16px;
        }

        .faq-trigger:hover {
            color: var(--primary);
        }

        .faq-icon-box {
            width: 32px;
            height: 32px;
            border-radius: 50%;
            background: #f1f5f9;
            color: var(--primary);
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 1.25rem;
            font-weight: 700;
            flex-shrink: 0;
            transition: all 0.3s ease;
        }

        .faq-item.active .faq-icon-box {
            background: var(--primary);
            color: #ffffff;
            transform: rotate(45deg);
        }

        .faq-content {
            max-height: 0;
            overflow: hidden;
            transition: max-height 0.35s ease, padding 0.3s ease;
            padding: 0 28px;
            color: #475569;
            font-size: 0.925rem;
            line-height: 1.75;
        }

        .faq-item.active .faq-content {
            max-height: 300px;
            padding: 0 28px 24px;
        }

        /* 板块 15: 样片申请与技术支持转化表单 (ID: #sample-form) */
        .sample-card-wrap {
            background: #ffffff;
            border-radius: 24px;
            border: 1px solid rgba(2, 132, 199, 0.3);
            box-shadow: var(--shadow-hover);
            padding: 48px;
            display: grid;
            grid-template-columns: 1.4fr 1fr;
            gap: 48px;
            position: relative;
            overflow: hidden;
        }

        .sample-card-wrap::before {
            content: '';
            position: absolute;
            top: 0;
            left: 0;
            right: 0;
            height: 6px;
            background: var(--gradient-brand);
        }

        .form-grid {
            display: grid;
            grid-template-columns: repeat(2, 1fr);
            gap: 18px;
            margin-top: 24px;
        }

        .form-group-full {
            grid-column: span 2;
        }

        .form-label {
            display: block;
            font-size: 0.85rem;
            font-weight: 700;
            color: var(--dark-graphite);
            margin-bottom: 8px;
        }

        .form-input, .form-select, .form-textarea {
            width: 100%;
            padding: 12px 16px;
            border-radius: 12px;
            border: 1px solid #cbd5e1;
            background: #f8fafc;
            color: var(--dark-graphite);
            font-size: 0.9rem;
            transition: all 0.2s ease;
            box-sizing: border-box;
        }

        .form-input:focus, .form-select:focus, .form-textarea:focus {
            outline: none;
            border-color: var(--primary);
            background: #ffffff;
            box-shadow: 0 0 0 4px rgba(2, 132, 199, 0.12);
        }

        .commit-sidebar {
            background: #f8fafc;
            border-radius: 18px;
            border: 1px solid #e2e8f0;
            padding: 32px 28px;
            display: flex;
            flex-direction: column;
            justify-content: space-between;
        }

        .commit-sidebar h4 {
            font-size: 1.2rem;
            font-weight: 800;
            color: var(--dark-graphite);
            margin-bottom: 20px;
        }

        .commit-list {
            list-style: none;
            display: flex;
            flex-direction: column;
            gap: 18px;
        }

        .commit-item {
            display: flex;
            gap: 14px;
            align-items: flex-start;
        }

        .commit-icon {
            width: 24px;
            height: 24px;
            border-radius: 50%;
            background: #dcfce7;
            color: #15803d;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 0.85rem;
            font-weight: 800;
            flex-shrink: 0;
            margin-top: 2px;
        }

        .commit-text h5 {
            font-size: 0.925rem;
            font-weight: 700;
            color: var(--dark-graphite);
            margin-bottom: 2px;
        }

        .commit-text p {
            font-size: 0.8125rem;
            color: var(--text-muted);
            line-height: 1.5;
        }

        /* 底部工业级全景页脚 */
        .site-footer {
            background-color: var(--dark-surface);
            color: #94a3b8;
            padding: 72px 0 28px;
            border-top: 1px solid rgba(255, 255, 255, 0.08);
            font-size: 0.875rem;
        }

        .footer-main-grid {
            display: grid;
            grid-template-columns: 1.4fr 1fr 1.1fr 1.1fr;
            gap: 48px;
            margin-bottom: 56px;
        }

        .footer-brand h3 {
            font-size: 1.4rem;
            font-weight: 800;
            color: #ffffff;
            margin-bottom: 12px;
        }

        .footer-brand p {
            color: #64748b;
            font-size: 0.85rem;
            line-height: 1.7;
            margin-bottom: 20px;
        }

        .footer-col h4 {
            font-size: 0.95rem;
            font-weight: 700;
            color: #ffffff;
            letter-spacing: 0.05em;
            margin-bottom: 18px;
            text-transform: uppercase;
        }

        .footer-links {
            list-style: none;
            display: flex;
            flex-direction: column;
            gap: 11px;
        }

        .footer-links a {
            color: #94a3b8;
            transition: color 0.2s;
        }

        .footer-links a:hover {
            color: #38bdf8;
            padding-left: 4px;
        }

        .footer-cert-tags {
            display: flex;
            flex-wrap: wrap;
            gap: 8px;
        }

        .cert-tag {
            background: rgba(255, 255, 255, 0.06);
            border: 1px solid rgba(255, 255, 255, 0.12);
            padding: 6px 12px;
            border-radius: 8px;
            font-size: 0.775rem;
            color: #cbd5e1;
            font-family: var(--font-mono);
        }

        .footer-bottom {
            padding-top: 28px;
            border-top: 1px solid rgba(255, 255, 255, 0.08);
            display: flex;
            justify-content: space-between;
            align-items: center;
            font-size: 0.8rem;
            color: #64748b;
            flex-wrap: wrap;
            gap: 16px;
        }

        .footer-bottom a {
            color: #64748b;
        }

        .footer-bottom a:hover {
            color: #94a3b8;
        }

        /* 响应式断点 */
        @media (max-width: 1024px) {
            .hero-grid {
                grid-template-columns: 1fr;
                gap: 36px;
            }
            .hero-card-display {
                display: none;
            }
            .metrics-grid, .advantages-grid, .products-grid, .arch-grid, .cases-grid, .reviews-grid, .news-grid {
                grid-template-columns: repeat(2, 1fr);
            }
            .timeline-grid, .quality-grid {
                grid-template-columns: repeat(2, 1fr);
            }
            .timeline-track {
                display: none;
            }
            .footer-main-grid {
                grid-template-columns: repeat(2, 1fr);
                gap: 36px;
            }
            .sample-card-wrap {
                grid-template-columns: 1fr;
            }
            .process-layout {
                grid-template-columns: 1fr;
            }
            .process-img-box img {
                height: 300px;
            }
        }

        @media (max-width: 768px) {
            .header-topbar {
                display: none;
            }
            .nav-menu {
                display: none;
                position: absolute;
                top: 76px;
                left: 0;
                right: 0;
                background: #ffffff;
                flex-direction: column;
                padding: 24px;
                border-bottom: 1px solid #e2e8f0;
                box-shadow: var(--shadow-card);
                gap: 16px;
                align-items: flex-start;
            }
            .nav-menu.open {
                display: flex;
            }
            .mobile-toggle {
                display: block;
            }
            .hero-content h1 {
                font-size: 2.1rem;
            }
            .section {
                padding: 56px 0;
            }
            .section-title {
                font-size: 1.75rem;
            }
            .metrics-grid, .advantages-grid, .products-grid, .arch-grid, .cases-grid, .reviews-grid, .news-grid, .timeline-grid, .quality-grid, .yield-grid {
                grid-template-columns: 1fr;
            }
            .form-grid {
                grid-template-columns: 1fr;
            }
            .form-group-full {
                grid-column: span 1;
            }
            .footer-main-grid {
                grid-template-columns: 1fr;
            }
            .sample-card-wrap {
                padding: 28px 20px;
            }
        }

        @media (max-width: 520px) {
            .hero-buttons {
                flex-direction: column;
                width: 100%;
            }
            .hero-buttons .btn {
                width: 100%;
            }
            .hero-specs-row {
                gap: 14px;
            }
            .spec-item .num {
                font-size: 1.15rem;
            }
            .metric-card, .adv-card, .product-card, .arch-card, .review-card, .news-card {
                padding: 22px;
            }
        }