/* roulang page: index */
:root {
      --primary: #0A0E17;
      --accent: #D4AF37;
      --bg: #F5F3EF;
      --card-bg: #FFFFFF;
      --border: #EAE6DF;
      --text: #1A1A1A;
      --text-light: #5C5C5C;
      --red-accent: #C0392B;
      --white: #FFFFFF;
      
      --font-sans: 'Noto Sans SC', 'PingFang SC', 'Inter', 'Roboto', sans-serif;
      --shadow-sm: 0 1px 3px rgba(0,0,0,0.04), 0 6px 16px rgba(0,0,0,0.06);
      --shadow-hover: 0 4px 8px rgba(0,0,0,0.06), 0 12px 24px rgba(0,0,0,0.08);
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-input: 6px;
      --radius-pill: 20px;
      --transition: 0.25s ease;
      --max-width: 1280px;
      --section-gap: 120px;
    }

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

    body {
      font-family: var(--font-sans);
      background-color: var(--bg);
      color: var(--text);
      line-height: 1.7;
      font-size: 17px;
      -webkit-font-smoothing: antialiased;
    }

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

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

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

    .container {
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 24px;
    }

    /* 导航 */
    #nav {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      transition: background 0.3s ease, box-shadow 0.3s ease, backdrop-filter 0.3s ease;
      background: transparent;
      padding: 16px 0;
    }

    #nav.scrolled {
      background: rgba(255,255,255,0.92);
      backdrop-filter: blur(12px);
      box-shadow: 0 1px 6px rgba(0,0,0,0.05);
    }

    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 24px;
    }

    .brand {
      font-size: 22px;
      font-weight: 700;
      color: var(--primary);
      letter-spacing: -0.3px;
    }

    .nav-links {
      display: flex;
      align-items: center;
      gap: 32px;
      list-style: none;
    }

    .nav-links a {
      font-size: 15px;
      color: var(--text-light);
      font-weight: 500;
      position: relative;
      padding: 4px 0;
      transition: color 0.2s;
    }

    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: -2px;
      left: 50%;
      transform: translateX(-50%) scaleX(0);
      width: 100%;
      height: 2px;
      background: var(--primary);
      transition: transform 0.25s ease;
      transform-origin: center;
    }

    .nav-links a:hover {
      color: var(--primary);
    }

    .nav-links a:hover::after {
      transform: translateX(-50%) scaleX(1);
    }

    .nav-cta {
      background: var(--accent);
      color: var(--white) !important;
      padding: 10px 22px !important;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 15px;
      transition: background 0.2s, transform 0.2s;
    }

    .nav-cta:hover {
      background: #c9a52b;
      transform: scale(1.03);
    }

    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
      background: none;
      border: none;
    }

    .hamburger span {
      width: 24px;
      height: 2px;
      background: var(--primary);
      transition: 0.3s;
    }

    .mobile-menu {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100vh;
      background: var(--white);
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      gap: 28px;
      z-index: 999;
      transform: translateY(-100%);
      transition: transform 0.4s ease;
    }

    .mobile-menu.open {
      transform: translateY(0);
    }

    .mobile-menu a {
      font-size: 20px;
      font-weight: 600;
      color: var(--primary);
    }

    .mobile-close {
      position: absolute;
      top: 24px;
      right: 24px;
      font-size: 28px;
      background: none;
      border: none;
      cursor: pointer;
    }

    /* 区块标题 */
    .section-title {
      font-size: 36px;
      font-weight: 700;
      line-height: 1.25;
      color: var(--primary);
      margin-bottom: 16px;
    }

    .section-sub {
      color: var(--text-light);
      font-size: 18px;
      margin-bottom: 48px;
    }

    /* Hero */
    #hero {
      padding: 160px 0 100px;
      background: radial-gradient(circle at 30% 40%, #F5F3EF 0%, #E8E4DB 100%);
      display: flex;
      align-items: center;
    }

    .hero-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 60px;
      align-items: center;
    }

    .hero-left h1 {
      font-size: 52px;
      font-weight: 800;
      line-height: 1.1;
      letter-spacing: -0.02em;
      color: var(--primary);
      margin-bottom: 24px;
    }

    .hero-left p {
      font-size: 18px;
      color: var(--text-light);
      margin-bottom: 36px;
      max-width: 90%;
    }

    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }

    .btn-primary {
      background: var(--accent);
      color: var(--white);
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 16px;
      letter-spacing: 0.05em;
      border: none;
      cursor: pointer;
      transition: background 0.2s, transform 0.2s;
    }

    .btn-primary:hover {
      background: #c9a52b;
      transform: scale(1.03);
    }

    .btn-outline {
      border: 2px solid var(--accent);
      color: var(--accent);
      background: transparent;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 16px;
      letter-spacing: 0.05em;
      transition: all 0.2s;
    }

    .btn-outline:hover {
      background: var(--accent);
      color: var(--white);
      transform: scale(1.03);
    }

    .hero-right {
      position: relative;
    }

    .hero-img {
      border-radius: 16px;
      box-shadow: 0 20px 40px rgba(212,175,55,0.15);
      width: 100%;
    }

    .data-badge {
      position: absolute;
      bottom: -18px;
      left: 20px;
      background: rgba(10,14,23,0.85);
      backdrop-filter: blur(8px);
      color: var(--white);
      padding: 12px 20px;
      border-radius: 12px;
      font-weight: 600;
      border-left: 4px solid var(--accent);
    }

    /* 优势 */
    #advantages {
      padding: var(--section-gap) 0;
    }

    .advantages-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }

    .adv-card {
      background: var(--card-bg);
      border: 1px solid var(--border);
      border-radius: var(--radius-card);
      padding: 32px 28px;
      transition: var(--transition);
      box-shadow: var(--shadow-sm);
    }

    .adv-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-hover);
      border-color: var(--accent);
    }

    .icon-geo {
      width: 40px;
      height: 40px;
      border: 2px solid var(--accent);
      display: flex;
      align-items: center;
      justify-content: center;
      margin-bottom: 20px;
      transition: transform 0.3s;
    }

    .adv-card:hover .icon-geo {
      transform: rotate(15deg);
    }

    .adv-card h3 {
      font-size: 22px;
      font-weight: 600;
      margin-bottom: 12px;
    }

    /* 服务 */
    #services {
      padding: var(--section-gap) 0;
    }

    .services-masonry {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }

    .service-card {
      background: var(--card-bg);
      border-radius: var(--radius-card);
      border: 1px solid var(--border);
      overflow: hidden;
      transition: var(--transition);
      box-shadow: var(--shadow-sm);
    }

    .service-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-hover);
      border-color: var(--accent);
    }

    .service-img {
      height: 200px;
      object-fit: cover;
      width: 100%;
    }

    .service-content {
      padding: 22px 28px;
    }

    .service-tag {
      background: var(--accent);
      color: var(--white);
      font-size: 12px;
      padding: 4px 12px;
      border-radius: var(--radius-pill);
      display: inline-block;
      margin-top: 12px;
    }

    /* 案例瀑布 */
    #cases {
      padding: var(--section-gap) 0;
    }

    .cases-waterfall {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 20px;
    }

    .case-card {
      background: var(--card-bg);
      border-radius: var(--radius-card);
      border: 1px solid var(--border);
      overflow: hidden;
      transition: var(--transition);
      box-shadow: var(--shadow-sm);
    }

    .case-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-hover);
      border-color: var(--accent);
    }

    .case-img {
      height: 180px;
      object-fit: cover;
    }

    .case-info {
      padding: 20px;
    }

    .case-stat {
      font-size: 28px;
      font-weight: 700;
      color: var(--accent);
    }

    /* 对比表 */
    #comparison {
      padding: var(--section-gap) 0;
    }

    .table-wrap {
      overflow-x: auto;
      border-radius: var(--radius-card);
    }

    .compare-table {
      width: 100%;
      border-collapse: collapse;
      background: var(--white);
    }

    .compare-table th {
      background: var(--primary);
      color: var(--white);
      padding: 20px;
      font-weight: 600;
    }

    .compare-table td, .compare-table th {
      padding: 16px 20px;
      border-bottom: 1px solid var(--border);
    }

    .highlight-col {
      background: #F9F7F2;
    }

    /* FAQ */
    #faq {
      padding: var(--section-gap) 0;
    }

    .faq-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 20px;
    }

    .faq-item {
      border-bottom: 1px solid var(--border);
      padding: 16px 0;
    }

    .faq-question {
      font-weight: 600;
      font-size: 18px;
      display: flex;
      justify-content: space-between;
      cursor: pointer;
    }

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease-in-out;
      color: var(--text-light);
    }

    /* CTA */
    #contact {
      background: var(--primary);
      color: var(--white);
      padding: 80px 0;
    }

    .contact-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 48px;
    }

    .contact-form input, .contact-form textarea {
      width: 100%;
      background: rgba(255,255,255,0.08);
      border: 1px solid rgba(255,255,255,0.2);
      border-radius: var(--radius-input);
      padding: 14px;
      color: white;
      margin-bottom: 20px;
    }

    .contact-form input:focus {
      border-color: var(--accent);
    }

    .social-icons i {
      font-size: 22px;
      margin-right: 16px;
      color: var(--white);
      transition: color 0.2s;
    }

    .social-icons i:hover {
      color: var(--accent);
    }

    /* footer */
    #footer {
      background: var(--primary);
      color: #ccc;
      padding: 60px 0 30px;
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
    }

    .tag-cloud span {
      background: #2a2e37;
      padding: 5px 12px;
      border-radius: 20px;
      font-size: 13px;
      margin: 4px;
      display: inline-block;
    }

    @media (max-width: 1024px) {
      .hero-grid, .advantages-grid, .services-masonry, .cases-waterfall, .contact-grid, .footer-grid {
        grid-template-columns: 1fr 1fr;
      }
      .faq-grid { grid-template-columns: 1fr; }
    }

    @media (max-width: 768px) {
      .nav-links { display: none; }
      .hamburger { display: flex; }
      .hero-grid, .advantages-grid, .services-masonry, .cases-waterfall, .contact-grid, .footer-grid {
        grid-template-columns: 1fr;
      }
      h1 { font-size: 38px !important; }
    }