/* roulang page: index */
:root {
      --primary: #1C1E21;
      --primary-dark: #111315;
      --accent: #D97706;
      --accent-hover: #B45309;
      --bg-surface: #F4F5F7;
      --bg-card: #FFFFFF;
      --text-main: #1F2937;
      --text-muted: #6B7280;
      --border-color: #E5E7EB;
      --border-dark: rgba(255, 255, 255, 0.08);
      --radius: 8px;
      --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.05);
      --shadow-md: 0 4px 20px -2px rgba(0, 0, 0, 0.06);
      --shadow-lg: 0 10px 25px -5px rgba(0, 0, 0, 0.1);
      --container-max: 1240px;
    }

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

    body {
      font-family: system-ui, -apple-system, "PingFang SC", "Microsoft YaHei", "Heiti SC", sans-serif;
      line-height: 1.75;
      color: var(--text-main);
      background-color: #FAFBFD;
      -webkit-font-smoothing: antialiased;
    }

    a {
      color: inherit;
      text-decoration: none;
      transition: color 0.2s ease;
    }

    img {
      max-width: 100%;
      height: auto;
      display: block;
      border-radius: var(--radius);
    }

    button, input, select {
      font-family: inherit;
    }

    .container {
      width: 100%;
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 1.5rem;
    }

    /* 顶部导航 */
    .top-bar {
      background: #111315;
      color: #9CA3AF;
      font-size: 0.8125rem;
      padding: 0.5rem 0;
      border-bottom: 1px solid rgba(255, 255, 255, 0.08);
    }
    .top-bar .container {
      display: flex;
      justify-content: space-between;
      align-items: center;
      flex-wrap: wrap;
      gap: 0.5rem;
    }
    .top-bar a:hover {
      color: var(--accent);
    }

    .header-nav {
      position: sticky;
      top: 0;
      background: rgba(255, 255, 255, 0.94);
      backdrop-filter: blur(12px);
      z-index: 999;
      box-shadow: 0 2px 10px rgba(0, 0, 0, 0.04);
      border-bottom: 1px solid var(--border-color);
    }
    .header-nav .container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 4.5rem;
    }
    .logo-box {
      display: flex;
      align-items: center;
      gap: 0.6rem;
      font-size: 1.35rem;
      font-weight: 800;
      color: var(--primary);
      letter-spacing: -0.5px;
    }
    .logo-badge {
      background: var(--accent);
      color: #FFF;
      padding: 0.2rem 0.5rem;
      border-radius: 4px;
      font-size: 0.75rem;
      font-weight: 700;
    }
    .nav-menu {
      display: flex;
      gap: 1.75rem;
      align-items: center;
      list-style: none;
    }
    .nav-menu a {
      font-weight: 600;
      font-size: 0.95rem;
      color: #374151;
      padding: 0.35rem 0;
      position: relative;
    }
    .nav-menu a:hover, .nav-menu a.active {
      color: var(--accent);
    }
    .nav-menu a.active::after {
      content: '';
      position: absolute;
      bottom: -4px;
      left: 0;
      width: 100%;
      height: 2px;
      background: var(--accent);
    }
    .btn-cta {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      background: var(--accent);
      color: #FFF;
      font-weight: 600;
      font-size: 0.9rem;
      padding: 0.65rem 1.4rem;
      border-radius: var(--radius);
      border: 1px solid rgba(0, 0, 0, 0.05);
      cursor: pointer;
      box-shadow: 0 2px 8px rgba(217, 119, 6, 0.25);
      transition: all 0.2s ease;
      white-space: nowrap;
    }
    .btn-cta:hover {
      background: var(--accent-hover);
      transform: translateY(-2px);
      box-shadow: 0 4px 12px rgba(217, 119, 6, 0.35);
    }

    /* 板块通用 */
    section {
      padding: 5.5rem 0;
      border-bottom: 1px solid var(--border-color);
    }
    .section-header {
      margin-bottom: 3.5rem;
      max-width: 780px;
    }
    .section-tag {
      display: inline-block;
      font-size: 0.75rem;
      text-transform: uppercase;
      font-weight: 700;
      color: var(--accent);
      background: rgba(217, 119, 6, 0.1);
      padding: 0.25rem 0.65rem;
      border-radius: 4px;
      margin-bottom: 0.75rem;
      letter-spacing: 0.5px;
    }
    .section-title {
      font-size: 2.15rem;
      font-weight: 800;
      color: var(--primary);
      line-height: 1.3;
      margin-bottom: 1rem;
    }
    .section-desc {
      font-size: 1.05rem;
      color: var(--text-muted);
      line-height: 1.8;
    }

    /* 板块一：Hero 对比选型 */
    .hero-section {
      background: linear-gradient(180deg, #FFFFFF 0%, #F4F5F7 100%);
      padding: 4.5rem 0 5.5rem;
    }
    .hero-grid {
      display: grid;
      grid-template-columns: 1.15fr 0.85fr;
      gap: 3.5rem;
      align-items: center;
    }
    .hero-h1 {
      font-size: 2.75rem;
      line-height: 1.25;
      font-weight: 800;
      color: var(--primary);
      margin-bottom: 1.25rem;
      letter-spacing: -0.5px;
    }
    .hero-p {
      font-size: 1.1rem;
      color: #4B5563;
      margin-bottom: 2rem;
      line-height: 1.8;
    }
    .hero-tiers {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 1.25rem;
      margin-top: 2rem;
    }
    .tier-card {
      background: #FFF;
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      padding: 1.5rem;
      box-shadow: var(--shadow-sm);
      position: relative;
    }
    .tier-card.featured {
      border: 2px solid var(--accent);
      box-shadow: var(--shadow-lg);
    }
    .tier-badge {
      position: absolute;
      top: -12px;
      right: 15px;
      background: var(--accent);
      color: #FFF;
      font-size: 0.75rem;
      font-weight: 700;
      padding: 0.2rem 0.6rem;
      border-radius: 20px;
    }
    .tier-title {
      font-size: 1.15rem;
      font-weight: 700;
      color: var(--primary);
      margin-bottom: 0.5rem;
    }
    .tier-features {
      list-style: none;
      font-size: 0.875rem;
      color: #4B5563;
      margin: 1rem 0 1.25rem;
    }
    .tier-features li {
      margin-bottom: 0.5rem;
      display: flex;
      align-items: center;
      gap: 0.4rem;
    }
    .tier-features li::before {
      content: '✓';
      color: var(--accent);
      font-weight: bold;
    }

    /* 板块二：品牌与工法介绍 */
    .brand-story {
      background: #FFFFFF;
    }
    .story-grid {
      display: grid;
      grid-template-columns: 1fr 1.1fr;
      gap: 3.5rem;
      align-items: center;
    }
    .story-img-wrap {
      position: relative;
      border-radius: var(--radius);
      overflow: hidden;
      box-shadow: var(--shadow-md);
    }
    .story-badge {
      position: absolute;
      bottom: 1.5rem;
      left: 1.5rem;
      background: rgba(17, 19, 21, 0.85);
      color: #FFF;
      padding: 0.75rem 1.25rem;
      border-radius: var(--radius);
      backdrop-filter: blur(8px);
      font-size: 0.875rem;
    }
    .story-badge strong {
      color: var(--accent);
      font-size: 1.25rem;
      display: block;
    }

    /* 板块三：核心优势矩阵 */
    .grid-3x2 {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 1.75rem;
    }
    .card-matrix {
      background: #FFF;
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      padding: 2rem 1.75rem;
      transition: all 0.25s ease;
      box-shadow: var(--shadow-sm);
    }
    .card-matrix:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-md);
      border-color: #D1D5DB;
    }
    .card-num {
      font-size: 1.75rem;
      font-weight: 800;
      color: #E5E7EB;
      margin-bottom: 1rem;
      font-family: monospace;
    }
    .card-matrix:hover .card-num {
      color: var(--accent);
    }
    .card-title {
      font-size: 1.2rem;
      font-weight: 700;
      color: var(--primary);
      margin-bottom: 0.75rem;
    }
    .card-text {
      font-size: 0.925rem;
      color: var(--text-muted);
      line-height: 1.75;
    }

    /* 板块四：指标看板 */
    .dashboard-strip {
      background: #F4F5F7;
      padding: 4rem 0;
    }
    .dash-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 2rem;
      text-align: center;
    }
    .dash-item {
      padding: 1.5rem;
      background: #FFF;
      border-radius: var(--radius);
      border: 1px solid var(--border-color);
    }
    .dash-val {
      font-size: 2.75rem;
      font-weight: 800;
      color: var(--primary);
      line-height: 1.1;
      margin-bottom: 0.5rem;
      font-family: monospace;
    }
    .dash-val span {
      color: var(--accent);
      font-size: 1.5rem;
      margin-left: 2px;
    }
    .dash-label {
      font-size: 1rem;
      font-weight: 700;
      color: var(--primary);
      margin-bottom: 0.35rem;
    }
    .dash-desc {
      font-size: 0.825rem;
      color: var(--text-muted);
    }

    /* 板块五：热门选型三大装备 */
    .trio-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 2rem;
    }
    .product-card {
      background: #FFF;
      border-radius: var(--radius);
      border: 1px solid var(--border-color);
      overflow: hidden;
      display: flex;
      flex-direction: column;
      box-shadow: var(--shadow-sm);
      transition: all 0.25s ease;
    }
    .product-card:hover {
      box-shadow: var(--shadow-lg);
      transform: translateY(-4px);
    }
    .product-img-box {
      height: 220px;
      overflow: hidden;
      position: relative;
    }
    .product-img-box img {
      width: 100%;
      height: 100%;
      object-fit: cover;
      transition: transform 0.4s ease;
    }
    .product-card:hover .product-img-box img {
      transform: scale(1.05);
    }
    .product-body {
      padding: 1.75rem;
      flex: 1;
      display: flex;
      flex-direction: column;
    }
    .product-tag {
      font-size: 0.75rem;
      font-weight: 700;
      color: var(--accent);
      margin-bottom: 0.5rem;
    }
    .product-name {
      font-size: 1.25rem;
      font-weight: 700;
      color: var(--primary);
      margin-bottom: 0.75rem;
    }
    .product-spec {
      background: #F9FAFB;
      padding: 0.75rem 1rem;
      border-radius: 4px;
      margin-bottom: 1rem;
      font-size: 0.85rem;
      color: #4B5563;
    }
    .product-spec div {
      display: flex;
      justify-content: space-between;
      margin-bottom: 0.25rem;
    }
    .product-spec div:last-child {
      margin-bottom: 0;
    }

    /* 板块六：深色极限施工区 */
    .dark-zone {
      background: var(--primary-dark);
      color: #FFF;
      border-bottom: 1px solid #222;
    }
    .dark-zone .section-title {
      color: #FFF;
    }
    .dark-zone .section-desc {
      color: #9CA3AF;
    }
    .dark-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 3rem;
      align-items: center;
    }
    .dark-card-list {
      display: flex;
      flex-direction: column;
      gap: 1.5rem;
    }
    .dark-card {
      background: #1C1E21;
      border: 1px solid var(--border-dark);
      padding: 1.5rem;
      border-radius: var(--radius);
      border-left: 3px solid var(--accent);
    }
    .dark-card h4 {
      font-size: 1.15rem;
      margin-bottom: 0.5rem;
      color: #F3F4F6;
    }
    .dark-card p {
      font-size: 0.9rem;
      color: #9CA3AF;
      line-height: 1.7;
    }

    /* 板块七：结果对比表 */
    .compare-container {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 2rem;
    }
    .compare-box {
      border-radius: var(--radius);
      padding: 2.25rem;
      border: 1px solid var(--border-color);
    }
    .compare-box.old {
      background: #FAFAFA;
    }
    .compare-box.pro {
      background: #FFF;
      border: 2px solid var(--accent);
      box-shadow: var(--shadow-md);
    }
    .compare-box h3 {
      font-size: 1.35rem;
      font-weight: 800;
      margin-bottom: 1.25rem;
      display: flex;
      align-items: center;
      gap: 0.5rem;
    }
    .compare-box.old h3 {
      color: #6B7280;
    }
    .compare-box.pro h3 {
      color: var(--primary);
    }
    .compare-list {
      list-style: none;
    }
    .compare-list li {
      padding: 1rem 0;
      border-bottom: 1px solid var(--border-color);
      font-size: 0.925rem;
      line-height: 1.7;
    }
    .compare-list li:last-child {
      border-bottom: none;
    }
    .compare-list strong {
      display: block;
      margin-bottom: 0.25rem;
    }

    /* 板块八：时间轴里程碑 */
    .timeline-wrap {
      position: relative;
      max-width: 900px;
      margin: 0 auto;
    }
    .timeline-wrap::before {
      content: '';
      position: absolute;
      top: 0;
      bottom: 0;
      left: 20px;
      width: 2px;
      background: #E5E7EB;
    }
    .time-node {
      position: relative;
      padding-left: 60px;
      margin-bottom: 2.5rem;
    }
    .time-node:last-child {
      margin-bottom: 0;
    }
    .node-dot {
      position: absolute;
      left: 11px;
      top: 4px;
      width: 20px;
      height: 20px;
      border-radius: 50%;
      background: #FFF;
      border: 4px solid var(--accent);
    }
    .node-phase {
      font-size: 0.8125rem;
      font-weight: 700;
      color: var(--accent);
      text-transform: uppercase;
      margin-bottom: 0.25rem;
    }
    .node-title {
      font-size: 1.2rem;
      font-weight: 700;
      color: var(--primary);
      margin-bottom: 0.5rem;
    }
    .node-content {
      background: #FFF;
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      padding: 1.25rem 1.5rem;
      font-size: 0.925rem;
      color: #4B5563;
      box-shadow: var(--shadow-sm);
    }

    /* 板块九：实操案例故事 */
    .case-card {
      background: #FFF;
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      overflow: hidden;
      display: grid;
      grid-template-columns: 1.1fr 1fr;
      box-shadow: var(--shadow-sm);
    }
    .case-img img {
      width: 100%;
      height: 100%;
      object-fit: cover;
      border-radius: 0;
    }
    .case-detail {
      padding: 2.5rem;
      display: flex;
      flex-direction: column;
      justify-content: center;
    }
    .case-meta {
      display: flex;
      gap: 1.5rem;
      font-size: 0.875rem;
      color: #6B7280;
      margin-bottom: 1rem;
      border-bottom: 1px solid var(--border-color);
      padding-bottom: 0.75rem;
    }
    .case-title {
      font-size: 1.45rem;
      font-weight: 800;
      color: var(--primary);
      margin-bottom: 1rem;
    }
    .case-quote {
      font-size: 0.95rem;
      color: #4B5563;
      line-height: 1.8;
      margin-bottom: 1.5rem;
    }

    /* 板块十：内嵌技术动态资讯 */
    .news-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 1.75rem;
    }
    .news-item {
      background: #FFF;
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      padding: 1.75rem;
      display: flex;
      flex-direction: column;
      box-shadow: var(--shadow-sm);
    }
    .news-date {
      font-size: 0.8125rem;
      color: #9CA3AF;
      margin-bottom: 0.5rem;
    }
    .news-item-title {
      font-size: 1.15rem;
      font-weight: 700;
      color: var(--primary);
      margin-bottom: 0.75rem;
      line-height: 1.4;
    }
    .news-excerpt {
      font-size: 0.875rem;
      color: var(--text-muted);
      line-height: 1.75;
      flex: 1;
      margin-bottom: 1.25rem;
    }

    /* 板块十一：常见专业问题 */
    .faq-accordion {
      max-width: 860px;
      margin: 0 auto;
    }
    .faq-entry {
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      background: #FFF;
      margin-bottom: 1rem;
      overflow: hidden;
    }
    .faq-entry input[type="checkbox"] {
      display: none;
    }
    .faq-header {
      padding: 1.25rem 1.5rem;
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
      font-weight: 700;
      font-size: 1.05rem;
      color: var(--primary);
    }
    .faq-icon {
      transition: transform 0.25s ease;
      font-weight: bold;
      color: var(--accent);
    }
    .faq-entry input:checked ~ .faq-header .faq-icon {
      transform: rotate(45deg);
    }
    .faq-content {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease, padding 0.3s ease;
      background: #FAFAFA;
      padding: 0 1.5rem;
      color: #4B5563;
      font-size: 0.925rem;
      line-height: 1.8;
      border-top: 1px solid transparent;
    }
    .faq-entry input:checked ~ .faq-content {
      max-height: 300px;
      padding: 1.25rem 1.5rem;
      border-top-color: var(--border-color);
    }

    /* 板块十二：收口转化表单 */
    .conversion-zone {
      background: #F4F5F7;
    }
    .form-wrap {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 3.5rem;
      background: #FFF;
      border-radius: var(--radius);
      border: 1px solid var(--border-color);
      padding: 3rem;
      box-shadow: var(--shadow-md);
    }
    .form-left h3 {
      font-size: 1.75rem;
      font-weight: 800;
      color: var(--primary);
      margin-bottom: 1rem;
    }
    .form-left p {
      color: var(--text-muted);
      line-height: 1.8;
      margin-bottom: 2rem;
    }
    .form-trust-item {
      display: flex;
      gap: 1rem;
      margin-bottom: 1.25rem;
    }
    .form-trust-icon {
      width: 24px;
      height: 24px;
      background: rgba(217, 119, 6, 0.15);
      color: var(--accent);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 0.85rem;
      font-weight: bold;
      flex-shrink: 0;
      margin-top: 2px;
    }
    .form-field {
      margin-bottom: 1.25rem;
    }
    .form-field label {
      display: block;
      font-size: 0.875rem;
      font-weight: 700;
      color: #374151;
      margin-bottom: 0.4rem;
    }
    .form-field input, .form-field select {
      width: 100%;
      padding: 0.75rem 1rem;
      border: 1px solid var(--border-color);
      border-radius: var(--radius);
      font-size: 0.95rem;
      background: #FAFAFA;
      transition: border-color 0.2s ease;
    }
    .form-field input:focus, .form-field select:focus {
      outline: none;
      border-color: var(--accent);
      background: #FFF;
    }
    .btn-submit {
      width: 100%;
      background: var(--accent);
      color: #FFF;
      border: none;
      padding: 0.85rem;
      font-size: 1rem;
      font-weight: 700;
      border-radius: var(--radius);
      cursor: pointer;
      transition: background 0.2s ease;
      box-shadow: 0 4px 12px rgba(217, 119, 6, 0.3);
    }
    .btn-submit:hover {
      background: var(--accent-hover);
    }

    /* 移动端菜单开关 */
    .menu-toggle {
      display: none;
      background: none;
      border: none;
      font-size: 1.5rem;
      cursor: pointer;
      color: var(--primary);
    }

    /* 页脚 */
    footer {
      background: var(--primary-dark);
      color: #9CA3AF;
      padding: 5rem 0 2rem;
      font-size: 0.875rem;
      border-top: 1px solid #222;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 1.5fr 1fr 1fr 1.25fr;
      gap: 3rem;
      margin-bottom: 3.5rem;
    }
    .footer-col h4 {
      color: #F3F4F6;
      font-size: 1.05rem;
      margin-bottom: 1.25rem;
      font-weight: 700;
    }
    .footer-links {
      list-style: none;
    }
    .footer-links li {
      margin-bottom: 0.65rem;
    }
    .footer-links a:hover {
      color: var(--accent);
    }
    .footer-contact li {
      margin-bottom: 0.75rem;
      line-height: 1.6;
    }
    .footer-bottom {
      border-top: 1px solid rgba(255, 255, 255, 0.08);
      padding-top: 2rem;
      display: flex;
      justify-content: space-between;
      align-items: center;
      flex-wrap: wrap;
      gap: 1rem;
      font-size: 0.8125rem;
    }

    /* 响应式断点 */
    @media (max-width: 1024px) {
      .hero-grid, .story-grid, .dark-grid, .case-card, .form-wrap {
        grid-template-columns: 1fr;
        gap: 2.5rem;
      }
      .grid-3x2, .trio-grid, .news-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .footer-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 2rem;
      }
      .dash-grid {
        grid-template-columns: repeat(2, 1fr);
      }
    }

    @media (max-width: 768px) {
      .top-bar {
        display: none;
      }
      .menu-toggle {
        display: block;
      }
      .nav-menu {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: #FFF;
        flex-direction: column;
        padding: 1.5rem;
        border-bottom: 1px solid var(--border-color);
        box-shadow: var(--shadow-lg);
        gap: 1rem;
      }
      .nav-menu.open {
        display: flex;
      }
      .hero-tiers, .grid-3x2, .trio-grid, .news-grid, .compare-container, .dash-grid {
        grid-template-columns: 1fr;
      }
      .footer-grid {
        grid-template-columns: 1fr;
      }
      .section-title {
        font-size: 1.75rem;
      }
      .hero-h1 {
        font-size: 2.15rem;
      }
      .form-wrap {
        padding: 1.75rem;
      }
      .timeline-wrap::before {
        left: 10px;
      }
      .time-node {
        padding-left: 35px;
      }
      .node-dot {
        left: 1px;
      }
    }