/* roulang page: index */
:root {
      --primary: #0F172A;
      --primary-light: #1E293B;
      --accent: #F97316;
      --accent-hover: #EA580C;
      --secondary: #0284C7;
      --bg-main: #F8FAFC;
      --bg-card: #FFFFFF;
      --bg-dark: #0B0F19;
      --text-main: #020617;
      --text-body: #334155;
      --text-muted: #64748B;
      --border: #E2E8F0;
      --border-dark: #1E293B;
      --radius: 6px;
      --shadow: 0 1px 3px 0 rgba(0, 0, 0, 0.05), 0 1px 2px 0 rgba(0, 0, 0, 0.03);
      --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
      --font-mono: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;
    }

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

    body {
      font-family: system-ui, -apple-system, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
      background-color: var(--bg-main);
      color: var(--text-body);
      line-height: 1.6;
      overflow-x: hidden;
      -webkit-font-smoothing: antialiased;
    }

    a {
      color: inherit;
      text-decoration: none;
    }

    img {
      max-width: 100%;
      height: auto;
      display: block;
    }

    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 24px;
    }

    /* 顶部双行导航 */
    .top-bar {
      background: #020617;
      color: #94A3B8;
      font-size: 13px;
      border-bottom: 1px solid rgba(255, 255, 255, 0.08);
    }
    .top-bar-inner {
      display: flex;
      justify-content: space-between;
      align-items: center;
      height: 38px;
    }
    .top-bar-meta {
      display: flex;
      gap: 20px;
    }
    .top-bar-meta span {
      display: inline-flex;
      align-items: center;
      gap: 6px;
    }

    .main-header {
      background: rgba(15, 23, 42, 0.95);
      backdrop-filter: blur(8px);
      position: sticky;
      top: 0;
      z-index: 100;
      border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    }
    .nav-container {
      display: flex;
      justify-content: space-between;
      align-items: center;
      height: 72px;
    }
    .brand-logo {
      display: flex;
      align-items: center;
      gap: 10px;
      font-size: 20px;
      font-weight: 700;
      color: #FFFFFF;
      letter-spacing: -0.5px;
    }
    .brand-logo .logo-badge {
      background: var(--accent);
      color: #FFFFFF;
      font-size: 11px;
      font-weight: 800;
      padding: 2px 6px;
      border-radius: 4px;
      text-transform: uppercase;
    }
    .nav-menu {
      display: flex;
      list-style: none;
      gap: 28px;
      align-items: center;
    }
    .nav-menu a {
      color: #CBD5E1;
      font-size: 15px;
      font-weight: 500;
      transition: color 0.2s ease;
    }
    .nav-menu a:hover {
      color: var(--accent);
    }
    .nav-cta {
      background: var(--accent);
      color: #FFFFFF !important;
      padding: 9px 18px;
      border-radius: var(--radius);
      font-weight: 600 !important;
      transition: background 0.2s ease;
    }
    .nav-cta:hover {
      background: var(--accent-hover);
    }

    /* 通用组件 */
    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 12px 24px;
      font-size: 15px;
      font-weight: 600;
      border-radius: var(--radius);
      cursor: pointer;
      transition: all 0.2s ease;
      border: 1px solid transparent;
      gap: 8px;
    }
    .btn-primary {
      background: var(--accent);
      color: #FFFFFF;
    }
    .btn-primary:hover {
      background: var(--accent-hover);
    }
    .btn-outline {
      border-color: #475569;
      color: #F8FAFC;
      background: rgba(15, 23, 42, 0.6);
    }
    .btn-outline:hover {
      background: rgba(255, 255, 255, 0.1);
      border-color: #94A3B8;
    }

    .section-title-wrap {
      text-align: center;
      max-width: 820px;
      margin: 0 auto 52px;
    }
    .section-tag {
      color: var(--accent);
      font-size: 13px;
      font-weight: 700;
      text-transform: uppercase;
      letter-spacing: 1.5px;
      margin-bottom: 8px;
      display: block;
      font-family: var(--font-mono);
    }
    .section-title {
      font-size: 32px;
      font-weight: 700;
      color: var(--text-main);
      line-height: 1.3;
      margin-bottom: 16px;
    }
    .section-desc {
      font-size: 16px;
      color: var(--text-muted);
      line-height: 1.7;
    }

    section {
      padding: 88px 0;
      position: relative;
    }

    /* 1. 首屏 */
    .hero-section {
      position: relative;
      background-color: var(--bg-dark);
      background-image: linear-gradient(rgba(11, 15, 25, 0.88), rgba(11, 15, 25, 0.94)), url('/assets/images/b3d24c56370542c6.webp');
      background-size: cover;
      background-position: center;
      color: #FFFFFF;
      padding: 96px 0 110px;
      border-bottom: 1px solid var(--border-dark);
    }
    .hero-grid {
      display: grid;
      grid-template-columns: 1.25fr 1fr;
      gap: 48px;
      align-items: center;
    }
    .hero-tag {
      display: inline-flex;
      align-items: center;
      gap: 8px;
      background: rgba(249, 115, 22, 0.12);
      border: 1px solid rgba(249, 115, 22, 0.35);
      color: #FDBA74;
      padding: 6px 14px;
      border-radius: 4px;
      font-size: 13px;
      font-weight: 600;
      margin-bottom: 24px;
    }
    .hero-title {
      font-size: 44px;
      line-height: 1.2;
      font-weight: 800;
      margin-bottom: 20px;
      letter-spacing: -0.5px;
    }
    .hero-subtitle {
      font-size: 17px;
      color: #CBD5E1;
      line-height: 1.8;
      margin-bottom: 32px;
    }
    .hero-cta-group {
      display: flex;
      gap: 16px;
      margin-bottom: 40px;
    }

    /* 蓝图要求：裂变首屏含进度条与邀请交互面板 */
    .hero-reward-card {
      background: rgba(15, 23, 42, 0.85);
      border: 1px solid rgba(255, 255, 255, 0.12);
      border-radius: 8px;
      padding: 28px;
      box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.5);
    }
    .reward-header {
      display: flex;
      justify-content: space-between;
      align-items: center;
      margin-bottom: 16px;
      padding-bottom: 12px;
      border-bottom: 1px solid rgba(255, 255, 255, 0.08);
    }
    .reward-title {
      font-size: 16px;
      font-weight: 700;
      color: #F8FAFC;
    }
    .reward-badge {
      background: rgba(2, 132, 199, 0.2);
      color: #38BDF8;
      border: 1px solid rgba(2, 132, 199, 0.4);
      font-size: 12px;
      padding: 2px 8px;
      border-radius: 4px;
      font-family: var(--font-mono);
    }
    .reward-desc {
      font-size: 14px;
      color: #94A3B8;
      margin-bottom: 20px;
      line-height: 1.6;
    }
    .progress-info {
      display: flex;
      justify-content: space-between;
      font-size: 13px;
      margin-bottom: 8px;
      color: #CBD5E1;
    }
    .progress-bar-bg {
      height: 8px;
      background: #1E293B;
      border-radius: 4px;
      overflow: hidden;
      margin-bottom: 20px;
    }
    .progress-bar-fill {
      height: 100%;
      width: 78%;
      background: linear-gradient(90deg, #0284C7, #F97316);
      border-radius: 4px;
    }
    .invite-box {
      display: flex;
      gap: 10px;
      background: #090D16;
      border: 1px dashed rgba(255, 255, 255, 0.2);
      padding: 10px 14px;
      border-radius: 6px;
      align-items: center;
    }
    .invite-code {
      font-family: var(--font-mono);
      font-size: 14px;
      color: #F8FAFC;
      font-weight: 600;
      flex: 1;
    }
    .invite-btn {
      background: #1E293B;
      border: 1px solid #334155;
      color: #F8FAFC;
      font-size: 13px;
      padding: 6px 12px;
      border-radius: 4px;
      cursor: pointer;
    }
    .invite-btn:hover {
      background: var(--accent);
      border-color: var(--accent);
    }

    /* 2. 内容日历 */
    .calendar-section {
      background: #FFFFFF;
      border-bottom: 1px solid var(--border);
    }
    .calendar-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
    }
    .calendar-card {
      border: 1px solid var(--border);
      border-radius: var(--radius);
      padding: 24px;
      background: var(--bg-main);
      position: relative;
      transition: transform 0.2s, border-color 0.2s;
    }
    .calendar-card:hover {
      border-color: var(--accent);
      transform: translateY(-2px);
    }
    .calendar-date {
      font-family: var(--font-mono);
      font-size: 13px;
      color: var(--accent);
      font-weight: 700;
      margin-bottom: 8px;
    }
    .calendar-title {
      font-size: 17px;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 10px;
    }
    .calendar-text {
      font-size: 14px;
      color: var(--text-muted);
      line-height: 1.6;
    }

    /* 3. 热门专题 (Hot Topics) */
    .topics-section {
      background: var(--bg-main);
    }
    .topics-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }
    .topic-card {
      background: #FFFFFF;
      border: 1px solid var(--border);
      border-radius: var(--radius);
      overflow: hidden;
      display: flex;
      flex-direction: column;
      box-shadow: var(--shadow);
    }
    .topic-img-wrap {
      height: 200px;
      overflow: hidden;
      position: relative;
    }
    .topic-img-wrap img {
      width: 100%;
      height: 100%;
      object-fit: cover;
      transition: transform 0.3s;
    }
    .topic-card:hover .topic-img-wrap img {
      transform: scale(1.04);
    }
    .topic-content {
      padding: 24px;
      flex: 1;
      display: flex;
      flex-direction: column;
    }
    .topic-badge {
      font-size: 12px;
      color: var(--secondary);
      font-weight: 600;
      margin-bottom: 8px;
    }
    .topic-title {
      font-size: 18px;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 12px;
    }
    .topic-desc {
      font-size: 14px;
      color: var(--text-body);
      line-height: 1.6;
      margin-bottom: 20px;
      flex: 1;
    }
    .topic-link {
      font-size: 14px;
      font-weight: 600;
      color: var(--accent);
      display: inline-flex;
      align-items: center;
      gap: 4px;
    }

    /* 4. 观点解读 */
    .insights-section {
      background: #FFFFFF;
      border-top: 1px solid var(--border);
      border-bottom: 1px solid var(--border);
    }
    .insights-layout {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 32px;
    }
    .insight-card {
      padding: 32px;
      background: #F8FAFC;
      border: 1px solid var(--border);
      border-left: 4px solid var(--secondary);
      border-radius: var(--radius);
    }
    .insight-author {
      display: flex;
      align-items: center;
      gap: 12px;
      margin-bottom: 16px;
    }
    .author-role {
      font-size: 13px;
      color: var(--text-muted);
    }
    .author-name {
      font-size: 15px;
      font-weight: 700;
      color: var(--text-main);
    }
    .insight-quote {
      font-size: 15px;
      color: var(--text-body);
      line-height: 1.7;
    }

    /* 5. 汽车芯片工具 资讯列表 */
    .news-section {
      background: var(--bg-main);
    }
    .news-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .news-card {
      background: #FFFFFF;
      border: 1px solid var(--border);
      padding: 24px;
      border-radius: var(--radius);
    }
    .news-time {
      font-family: var(--font-mono);
      font-size: 12px;
      color: var(--text-muted);
      margin-bottom: 8px;
    }
    .news-title {
      font-size: 17px;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 12px;
    }
    .news-summary {
      font-size: 14px;
      color: var(--text-body);
      line-height: 1.6;
    }

    /* 6. 媒体精选 (Media Selects) */
    .media-section {
      background: #FFFFFF;
      border-top: 1px solid var(--border);
      border-bottom: 1px solid var(--border);
    }
    .media-row {
      display: grid;
      grid-template-columns: 1fr 1fr 1fr;
      gap: 28px;
    }
    .media-item {
      border: 1px solid var(--border);
      border-radius: var(--radius);
      padding: 24px;
      background: #F8FAFC;
    }
    .media-source {
      font-weight: 700;
      color: var(--secondary);
      font-size: 13px;
      margin-bottom: 8px;
    }
    .media-headline {
      font-size: 16px;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 12px;
    }
    .media-desc {
      font-size: 14px;
      color: var(--text-body);
      line-height: 1.6;
    }

    /* 7. 数据分析 (Data & Benchmarks) */
    .metrics-section {
      background: var(--bg-dark);
      color: #FFFFFF;
      padding: 80px 0;
    }
    .metrics-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
    }
    .metric-box {
      text-align: center;
      padding: 32px 16px;
      background: rgba(255, 255, 255, 0.03);
      border: 1px solid rgba(255, 255, 255, 0.08);
      border-radius: var(--radius);
    }
    .metric-value {
      font-family: var(--font-mono);
      font-size: 40px;
      font-weight: 800;
      color: var(--accent);
      margin-bottom: 8px;
    }
    .metric-label {
      font-size: 16px;
      font-weight: 600;
      color: #F8FAFC;
      margin-bottom: 6px;
    }
    .metric-sub {
      font-size: 13px;
      color: #94A3B8;
    }

    /* 8. 平台保障 (Guarantees & Standards) */
    .standards-section {
      background: #FFFFFF;
    }
    .standards-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }
    .standard-card {
      border: 1px solid var(--border);
      border-radius: var(--radius);
      padding: 30px;
      background: var(--bg-main);
      border-top: 3px solid var(--accent);
    }
    .standard-code {
      font-family: var(--font-mono);
      font-size: 14px;
      font-weight: 700;
      color: var(--accent);
      margin-bottom: 8px;
    }
    .standard-title {
      font-size: 18px;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 12px;
    }
    .standard-text {
      font-size: 14px;
      color: var(--text-body);
      line-height: 1.6;
    }

    /* 9. 扩展板块：参数速览 (Specs Overview) */
    .specs-section {
      background: #F1F5F9;
      border-top: 1px solid var(--border);
    }
    .specs-table-wrap {
      background: #FFFFFF;
      border: 1px solid var(--border);
      border-radius: var(--radius);
      overflow-x: auto;
    }
    .specs-table {
      width: 100%;
      border-collapse: collapse;
      text-align: left;
      font-size: 14px;
    }
    .specs-table th, .specs-table td {
      padding: 16px 20px;
      border-bottom: 1px solid var(--border);
    }
    .specs-table th {
      background: #F8FAFC;
      font-weight: 700;
      color: var(--text-main);
    }
    .specs-table tr:last-child td {
      border-bottom: none;
    }
    .specs-table code {
      font-family: var(--font-mono);
      color: var(--secondary);
      font-weight: 600;
    }

    /* 10. 扩展板块：行业场景演示 (Use Cases) */
    .scenarios-section {
      background: #FFFFFF;
    }
    .scenarios-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .scenario-card {
      border: 1px solid var(--border);
      border-radius: var(--radius);
      padding: 24px;
      background: #FAFAFA;
    }
    .scenario-phase {
      display: inline-block;
      font-size: 12px;
      font-weight: 700;
      background: #E2E8F0;
      padding: 3px 8px;
      border-radius: 4px;
      margin-bottom: 12px;
      color: var(--text-main);
    }
    .scenario-title {
      font-size: 17px;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 10px;
    }
    .scenario-desc {
      font-size: 14px;
      color: var(--text-body);
      line-height: 1.6;
    }

    /* 11. 扩展板块：车规芯片烧录与调试 FAQ */
    .faq-section {
      background: var(--bg-main);
      border-top: 1px solid var(--border);
    }
    .faq-list {
      max-width: 860px;
      margin: 0 auto;
      display: flex;
      flex-direction: column;
      gap: 16px;
    }
    .faq-item {
      background: #FFFFFF;
      border: 1px solid var(--border);
      border-radius: var(--radius);
      padding: 20px 24px;
    }
    .faq-item summary {
      font-size: 16px;
      font-weight: 700;
      color: var(--text-main);
      cursor: pointer;
      list-style: none;
      display: flex;
      justify-content: space-between;
      align-items: center;
    }
    .faq-item summary::-webkit-details-marker {
      display: none;
    }
    .faq-item summary::after {
      content: "+";
      font-size: 20px;
      color: var(--accent);
      font-weight: 400;
    }
    .faq-item[open] summary::after {
      content: "−";
    }
    .faq-item p {
      margin-top: 14px;
      font-size: 14px;
      color: var(--text-body);
      line-height: 1.7;
      border-top: 1px solid var(--border);
      padding-top: 12px;
    }

    /* 12. 订阅条与需求对接 (CTA Strip) */
    .subscribe-strip {
      background: var(--primary);
      color: #FFFFFF;
      padding: 72px 0;
      border-top: 1px solid var(--border-dark);
    }
    .strip-box {
      display: grid;
      grid-template-columns: 1.2fr 1fr;
      gap: 40px;
      align-items: center;
    }
    .strip-title {
      font-size: 28px;
      font-weight: 700;
      margin-bottom: 12px;
    }
    .strip-desc {
      color: #94A3B8;
      font-size: 15px;
      line-height: 1.6;
    }
    .strip-form {
      display: flex;
      gap: 12px;
    }
    .strip-input {
      flex: 1;
      padding: 14px 18px;
      background: #090D16;
      border: 1px solid #334155;
      border-radius: var(--radius);
      color: #FFFFFF;
      font-size: 15px;
    }
    .strip-input:focus {
      outline: none;
      border-color: var(--accent);
    }

    /* 页脚 */
    .main-footer {
      background: #060911;
      color: #64748B;
      padding: 64px 0 32px;
      font-size: 14px;
      border-top: 1px solid rgba(255, 255, 255, 0.05);
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1.5fr;
      gap: 40px;
      margin-bottom: 48px;
    }
    .footer-brand {
      font-size: 18px;
      font-weight: 700;
      color: #F8FAFC;
      margin-bottom: 14px;
    }
    .footer-desc {
      line-height: 1.7;
      margin-bottom: 16px;
    }
    .footer-heading {
      font-size: 15px;
      font-weight: 700;
      color: #CBD5E1;
      margin-bottom: 18px;
    }
    .footer-links {
      list-style: none;
      display: flex;
      flex-direction: column;
      gap: 10px;
    }
    .footer-links a:hover {
      color: #FFFFFF;
    }
    .footer-contact-item {
      margin-bottom: 10px;
    }
    .footer-bottom {
      border-top: 1px solid rgba(255, 255, 255, 0.08);
      padding-top: 28px;
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-size: 13px;
    }

    /* 响应式断点 */
    @media (max-width: 1024px) {
      .hero-grid, .strip-box {
        grid-template-columns: 1fr;
      }
      .calendar-grid, .metrics-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .topics-grid, .standards-grid, .scenarios-grid, .news-grid, .media-row {
        grid-template-columns: repeat(2, 1fr);
      }
      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }
    }

    @media (max-width: 768px) {
      .top-bar-meta span:last-child {
        display: none;
      }
      .nav-menu {
        display: none;
      }
      .hero-title {
        font-size: 32px;
      }
      .calendar-grid, .metrics-grid, .topics-grid, .standards-grid, .scenarios-grid, .news-grid, .media-row, .insights-layout {
        grid-template-columns: 1fr;
      }
      .strip-form {
        flex-direction: column;
      }
      .footer-grid {
        grid-template-columns: 1fr;
      }
      .footer-bottom {
        flex-direction: column;
        gap: 12px;
        text-align: center;
      }
    }