/* roulang page: index */
:root {
      --primary: #0F1F1A;
      --accent: #C8A96E;
      --bg-warm: #FAF8F5;
      --bg-dark: #0A1510;
      --card-bg: #FFFFFF;
      --data-bg: #F0F3F1;
      --text-primary: #0F1F1A;
      --text-body: #3A3F3D;
      --text-muted: #7A7F7D;
      --text-light: #FFFFFF;
      --text-warm: #E8E3D9;
      --border-light: #E5E2DD;
      --border-data: #D5D9D6;
      --success: #2D5A46;
      --warning: #C87A2E;
      --link: #1A6B4A;
      --shadow-sm: 0 4px 20px rgba(15,31,26,0.04);
      --shadow-card: 0 4px 20px rgba(15,31,26,0.06);
      --shadow-hover: 0 12px 32px rgba(15,31,26,0.10);
      --shadow-nav: 0 2px 16px rgba(15,31,26,0.08);
      --shadow-btn: 0 6px 18px rgba(200,169,110,0.25);
      --radius-lg: 12px;
      --radius-md: 8px;
      --radius-sm: 6px;
      --radius-xs: 4px;
      --font-cn: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", system-ui, sans-serif;
      --font-en: "Inter", "SF Pro Display", -apple-system, sans-serif;
      --max-width: 1280px;
      --gap-section: 120px;
      --gap-mobile: 80px;
      --card-padding: 32px;
      --card-padding-m: 24px;
      --transition-default: 0.3s ease;
      --transition-smooth: 0.6s ease-out;
    }

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

    html {
      scroll-behavior: smooth;
      font-size: 16px;
    }

    body {
      font-family: var(--font-cn);
      background-color: var(--bg-warm);
      color: var(--text-body);
      line-height: 1.75;
      -webkit-font-smoothing: antialiased;
      overflow-x: hidden;
    }

    .container {
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 32px;
    }

    @media (max-width: 1024px) {
      .container {
        padding: 0 24px;
      }
    }

    @media (max-width: 768px) {
      .container {
        padding: 0 20px;
      }
    }

    /* 导航 */
    .main-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      padding: 20px 40px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      background: transparent;
      transition: background 0.3s, box-shadow 0.3s, padding 0.3s;
    }

    .main-header.scrolled {
      background: rgba(255,255,255,0.95);
      backdrop-filter: blur(12px);
      box-shadow: var(--shadow-nav);
      padding: 16px 40px;
    }

    .logo {
      display: flex;
      align-items: center;
      height: 36px;
      font-size: 24px;
      font-weight: 700;
      letter-spacing: -0.02em;
      color: var(--text-light);
      transition: color 0.3s;
      text-decoration: none;
      font-family: var(--font-cn);
    }

    .main-header.scrolled .logo {
      color: var(--primary);
    }

    .nav-links {
      display: flex;
      gap: 40px;
      align-items: center;
      list-style: none;
    }

    .nav-links a {
      text-decoration: none;
      font-size: 16px;
      font-weight: 500;
      color: var(--text-warm);
      transition: color 0.3s;
      position: relative;
      padding-bottom: 6px;
    }

    .main-header.scrolled .nav-links a {
      color: var(--text-primary);
    }

    .nav-links a:hover,
    .nav-links a.active {
      color: var(--accent);
    }

    .nav-links a.active::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 100%;
      height: 2px;
      background: var(--accent);
    }

    .nav-cta {
      background: var(--accent);
      color: var(--text-light) !important;
      padding: 12px 28px;
      border-radius: var(--radius-sm);
      font-weight: 600;
      transition: background 0.3s, box-shadow 0.3s;
    }

    .nav-cta:hover {
      background: #b8944f;
      box-shadow: var(--shadow-btn);
    }

    .mobile-toggle {
      display: none;
      background: none;
      border: none;
      cursor: pointer;
      padding: 8px;
      flex-direction: column;
      gap: 5px;
      z-index: 1001;
    }

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

    .main-header:not(.scrolled) .mobile-toggle span {
      background: var(--text-light);
    }

    .mobile-menu {
      position: fixed;
      top: 0;
      right: -100%;
      width: 100%;
      height: 100vh;
      background: var(--primary);
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      gap: 32px;
      transition: right 0.35s ease-out;
      z-index: 1000;
    }

    .mobile-menu.active {
      right: 0;
    }

    .mobile-menu a {
      color: var(--text-light);
      font-size: 24px;
      text-decoration: none;
      font-weight: 500;
    }

    .mobile-close {
      position: absolute;
      top: 24px;
      right: 24px;
      background: none;
      border: none;
      color: var(--text-light);
      font-size: 32px;
      cursor: pointer;
    }

    @media (max-width: 1024px) {
      .nav-links {
        display: none;
      }
      .mobile-toggle {
        display: flex;
      }
    }

    /* 板块通用 */
    section {
      padding: var(--gap-section) 0;
    }

    @media (max-width: 768px) {
      section {
        padding: var(--gap-mobile) 0;
      }
    }

    .section-title {
      font-size: 42px;
      font-weight: 600;
      line-height: 1.2;
      color: var(--text-primary);
      letter-spacing: -0.02em;
      margin-bottom: 16px;
    }

    .section-subtitle {
      font-size: 20px;
      color: var(--text-muted);
      margin-bottom: 48px;
      max-width: 680px;
    }

    @media (max-width: 768px) {
      .section-title {
        font-size: 28px;
      }
      .section-subtitle {
        font-size: 18px;
        margin-bottom: 32px;
      }
    }

    /* Hero */
    .hero {
      height: 100vh;
      min-height: 700px;
      background: var(--primary);
      background-image: radial-gradient(circle at 85% 30%, rgba(200,169,110,0.12) 0%, transparent 50%);
      display: flex;
      align-items: center;
      position: relative;
      overflow: hidden;
    }

    .hero-content {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 32px;
    }

    .hero-text {
      width: 55%;
      z-index: 2;
    }

    .hero h1 {
      font-size: 56px;
      font-weight: 700;
      line-height: 1.15;
      color: var(--text-light);
      letter-spacing: -0.02em;
      margin-bottom: 24px;
    }

    .hero-sub {
      font-size: 20px;
      color: var(--text-warm);
      margin-bottom: 40px;
    }

    .hero-buttons {
      display: flex;
      gap: 20px;
      flex-wrap: wrap;
    }

    .btn-primary {
      background: var(--accent);
      color: var(--text-light);
      padding: 16px 40px;
      border-radius: var(--radius-sm);
      font-weight: 600;
      text-decoration: none;
      transition: background 0.3s, box-shadow 0.3s;
      border: none;
      cursor: pointer;
      display: inline-block;
    }

    .btn-primary:hover {
      background: #b8944f;
      box-shadow: var(--shadow-btn);
    }

    .btn-outline {
      border: 1.5px solid var(--text-warm);
      color: var(--text-warm);
      padding: 16px 40px;
      border-radius: var(--radius-sm);
      font-weight: 500;
      text-decoration: none;
      transition: all 0.3s;
      background: transparent;
    }

    .btn-outline:hover {
      background: rgba(255,255,255,0.08);
      border-color: var(--accent);
      color: var(--accent);
    }

    .hero-graphic {
      width: 45%;
      height: 450px;
      position: relative;
    }

    .graphic-lines {
      position: absolute;
      width: 100%;
      height: 100%;
      opacity: 0.7;
    }

    .line {
      position: absolute;
      background: rgba(200,169,110,0.25);
    }

    .line1 { width: 120px; height: 1px; top: 20%; left: 10%; transform: rotate(25deg); }
    .line2 { width: 90px; height: 2px; top: 35%; right: 15%; transform: rotate(-15deg); background: var(--accent); }
    .line3 { width: 160px; height: 1px; bottom: 30%; left: 20%; transform: rotate(45deg); }
    .line4 { width: 70px; height: 1px; top: 55%; right: 25%; transform: rotate(10deg); }
    .line5 { width: 100px; height: 2px; bottom: 20%; right: 30%; background: var(--accent); transform: rotate(-35deg); }
    .dot {
      position: absolute;
      width: 6px;
      height: 6px;
      background: var(--accent);
      border-radius: 50%;
    }

    @media (max-width: 1024px) {
      .hero-content {
        flex-direction: column;
        text-align: center;
      }
      .hero-text, .hero-graphic {
        width: 100%;
      }
      .hero-graphic {
        height: 200px;
        margin-top: 40px;
      }
      .hero h1 {
        font-size: 42px;
      }
    }

    @media (max-width: 768px) {
      .hero h1 {
        font-size: 36px;
      }
      .hero-buttons {
        flex-direction: column;
        align-items: center;
      }
    }

    /* 优势 */
    .advantages-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 24px;
    }

    .adv-card {
      background: var(--card-bg);
      border-radius: var(--radius-md);
      padding: var(--card-padding);
      box-shadow: var(--shadow-sm);
      transition: transform 0.3s, box-shadow 0.3s;
    }

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

    .adv-card.large {
      grid-row: span 2;
    }

    .adv-icon {
      width: 48px;
      height: 48px;
      background: var(--data-bg);
      border-radius: var(--radius-xs);
      display: flex;
      align-items: center;
      justify-content: center;
      color: var(--accent);
      font-size: 24px;
      margin-bottom: 20px;
    }

    .adv-card h4 {
      font-size: 20px;
      font-weight: 600;
      color: var(--text-primary);
      margin-bottom: 12px;
    }

    .adv-desc {
      color: var(--text-body);
      margin-bottom: 20px;
    }

    .adv-stat {
      font-size: 32px;
      font-weight: 700;
      font-family: var(--font-en);
      color: var(--accent);
      letter-spacing: -0.04em;
    }

    @media (max-width: 768px) {
      .advantages-grid {
        grid-template-columns: 1fr;
      }
    }

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

    .service-card {
      background: var(--bg-warm);
      border: 1px solid var(--border-light);
      border-radius: var(--radius-md);
      padding: var(--card-padding);
      transition: all 0.3s;
    }

    .service-card:hover {
      border-color: var(--accent);
      background: var(--card-bg);
    }

    .service-num {
      font-size: 14px;
      color: var(--text-muted);
      margin-bottom: 8px;
    }

    .service-card h4 {
      font-size: 20px;
      font-weight: 600;
      color: var(--text-primary);
      margin-bottom: 12px;
    }

    .service-link {
      color: var(--accent);
      text-decoration: none;
      font-weight: 500;
      margin-top: 20px;
      display: inline-block;
    }

    @media (max-width: 1024px) {
      .services-grid {
        grid-template-columns: repeat(2, 1fr);
      }
    }

    @media (max-width: 768px) {
      .services-grid {
        grid-template-columns: 1fr;
      }
    }

    /* 数据 */
    .data-band {
      background: var(--data-bg);
      padding: 80px 0;
    }

    .data-scroll {
      display: flex;
      justify-content: space-between;
      overflow-x: auto;
      scrollbar-width: none;
    }

    .data-item {
      text-align: center;
      padding: 0 24px;
      border-right: 1px solid var(--border-data);
      flex: 1;
    }

    .data-item:last-child {
      border-right: none;
    }

    .data-number {
      font-size: 64px;
      font-weight: 700;
      font-family: var(--font-en);
      color: var(--accent);
      letter-spacing: -0.04em;
    }

    @media (max-width: 768px) {
      .data-number {
        font-size: 42px;
      }
      .data-item {
        min-width: 160px;
      }
    }

    /* 案例 */
    .case-row {
      display: flex;
      gap: 60px;
      align-items: center;
      margin-bottom: 80px;
    }

    .case-img {
      width: 50%;
      height: 380px;
      background: #e5e2dd;
      border-radius: var(--radius-lg);
      overflow: hidden;
    }

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

    .case-text {
      width: 50%;
    }

    .case-tag {
      font-size: 12px;
      letter-spacing: 0.1em;
      color: var(--accent);
      font-weight: 600;
      margin-bottom: 12px;
    }

    @media (max-width: 1024px) {
      .case-row {
        flex-direction: column;
        gap: 32px;
      }
      .case-img, .case-text {
        width: 100%;
      }
    }

    /* 方案 */
    .steps-vertical {
      display: flex;
      flex-direction: column;
      align-items: center;
      gap: 24px;
    }

    .step-node {
      display: flex;
      align-items: center;
      gap: 24px;
      width: 100%;
      max-width: 680px;
    }

    .step-icon {
      width: 64px;
      height: 64px;
      background: var(--data-bg);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      color: var(--accent);
      font-size: 28px;
    }

    /* FAQ */
    .faq-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 0 40px;
    }

    .faq-item {
      border-bottom: 1px solid var(--border-light);
      padding: 20px 0;
    }

    .faq-question {
      font-weight: 500;
      font-size: 18px;
      display: flex;
      justify-content: space-between;
      cursor: pointer;
      color: var(--text-primary);
    }

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

    @media (max-width: 768px) {
      .faq-grid {
        grid-template-columns: 1fr;
      }
    }

    /* CTA */
    .cta-section {
      background: var(--bg-dark);
      color: var(--text-light);
    }

    .cta-wrapper {
      display: flex;
      gap: 60px;
    }

    .cta-form {
      background: var(--card-bg);
      border-radius: var(--radius-lg);
      padding: 40px;
      width: 50%;
    }

    .cta-form input, .cta-form textarea {
      width: 100%;
      padding: 14px;
      border: 1px solid var(--border-light);
      border-radius: var(--radius-sm);
      margin-bottom: 16px;
      font-family: inherit;
    }

    @media (max-width: 768px) {
      .cta-wrapper {
        flex-direction: column;
      }
      .cta-form {
        width: 100%;
      }
    }

    /* Footer */
    .footer {
      background: var(--primary);
      color: var(--text-warm);
      padding: 60px 0 30px;
    }

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

    @media (max-width: 768px) {
      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }
    }

    .footer-bottom {
      border-top: 1px solid rgba(255,255,255,0.1);
      margin-top: 40px;
      padding-top: 20px;
      text-align: center;
      font-size: 12px;
      color: var(--text-muted);
    }