/* roulang page: index */
:root {
      --primary: #1A8C3E;
      --primary-deep: #147A34;
      --primary-soft: rgba(26, 140, 62, 0.10);
      --accent: #F25C05;
      --accent-light: #E9732C;
      --bg-page: #F9F9F7;
      --bg-dark: #1E1E1E;
      --card-bg: #FFFFFF;
      --text-primary: #111111;
      --text-body: #3A3A3A;
      --text-muted: #6B6B6B;
      --text-on-dark: #F0F0F0;
      --border-light: rgba(0,0,0,0.05);
      --shadow-card: 0 2px 12px rgba(0,0,0,0.04), 0 1px 2px rgba(0,0,0,0.06);
      --shadow-hover: 0 8px 24px rgba(0,0,0,0.08);
      --radius-sm: 8px;
      --radius-md: 12px;
      --radius-lg: 16px;
      --font-sans: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", "Helvetica Neue", sans-serif;
      --transition: 0.25s ease;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    body {
      font-family: var(--font-sans);
      background-color: var(--bg-page);
      color: var(--text-body);
      line-height: 1.7;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
    }
    button, input {
      font-family: inherit;
      border: none;
      outline: none;
      background: none;
    }
    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 20px;
      width: 100%;
    }
    /* 导航 */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      background: rgba(255,255,255,0.92);
      backdrop-filter: blur(8px);
      z-index: 99;
      border-bottom: 1px solid var(--border-light);
      transition: box-shadow var(--transition);
    }
    .site-header.scrolled {
      box-shadow: 0 1px 8px rgba(0,0,0,0.06);
    }
    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 68px;
    }
    .logo-area {
      display: flex;
      align-items: center;
      gap: 8px;
      font-size: 22px;
      font-weight: 700;
      color: var(--primary);
    }
    .logo-icon {
      width: 34px;
      height: 34px;
      background: var(--primary);
      border-radius: 8px;
      display: flex;
      align-items: center;
      justify-content: center;
      color: white;
      font-size: 18px;
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 28px;
    }
    .nav-links a {
      font-size: 16px;
      font-weight: 500;
      color: var(--text-body);
      transition: color var(--transition);
      position: relative;
      padding: 4px 0;
    }
    .nav-links a:hover,
    .nav-links a.active {
      color: var(--primary);
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: -2px;
      left: 0;
      width: 0%;
      height: 2px;
      background: var(--primary);
      transition: width var(--transition);
    }
    .nav-links a:hover::after,
    .nav-links a.active::after {
      width: 100%;
    }
    .btn-primary {
      background: var(--primary);
      color: white;
      font-weight: 600;
      font-size: 16px;
      padding: 12px 24px;
      border-radius: var(--radius-sm);
      display: inline-flex;
      align-items: center;
      justify-content: center;
      cursor: pointer;
      transition: background var(--transition), box-shadow var(--transition);
      letter-spacing: 0.5px;
    }
    .btn-primary:hover {
      background: var(--primary-deep);
      box-shadow: 0 0 0 3px rgba(26,140,62,0.3);
    }
    .btn-outline {
      background: transparent;
      border: 2px solid var(--primary);
      color: var(--primary);
      font-weight: 600;
      padding: 10px 24px;
      border-radius: var(--radius-sm);
      transition: all var(--transition);
      cursor: pointer;
    }
    .btn-outline:hover {
      background: var(--primary-soft);
    }
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
    }
    .hamburger span {
      width: 24px;
      height: 2.5px;
      background: var(--primary);
      border-radius: 2px;
      transition: var(--transition);
    }
    .mobile-menu {
      position: fixed;
      top: 0;
      right: -100%;
      width: 280px;
      height: 100vh;
      background: white;
      box-shadow: -4px 0 20px rgba(0,0,0,0.1);
      padding: 24px;
      display: flex;
      flex-direction: column;
      transition: right 0.3s ease;
      z-index: 100;
    }
    .mobile-menu.active {
      right: 0;
    }
    .mobile-menu a {
      padding: 16px 0;
      font-size: 18px;
      border-bottom: 1px solid var(--border-light);
      color: var(--text-body);
    }
    .overlay {
      position: fixed;
      inset: 0;
      background: rgba(0,0,0,0.4);
      z-index: 99;
      display: none;
    }
    .overlay.show {
      display: block;
    }

    /* 区块通用 */
    section {
      padding: 100px 0;
    }
    .section-title {
      font-size: 32px;
      font-weight: 600;
      color: var(--text-primary);
      margin-bottom: 16px;
      line-height: 1.3;
    }
    .title-underline {
      width: 48px;
      height: 4px;
      background: var(--primary);
      margin-bottom: 40px;
    }
    /* Hero */
    .hero {
      padding: 120px 0 80px;
      background: linear-gradient(135deg, #F9F9F7 0%, #f0f5f1 100%);
    }
    .hero-grid {
      display: flex;
      align-items: center;
      gap: 60px;
    }
    .hero-text {
      flex: 1;
    }
    .hero-text h1 {
      font-size: 42px;
      font-weight: 700;
      line-height: 1.2;
      color: var(--text-primary);
      letter-spacing: -0.5px;
      margin-bottom: 20px;
    }
    .hero-text .sub {
      font-size: 18px;
      color: var(--text-body);
      margin-bottom: 32px;
    }
    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .hero-stats {
      display: flex;
      gap: 32px;
      margin-top: 40px;
    }
    .stat-item strong {
      font-size: 28px;
      color: var(--primary);
      display: block;
    }
    .hero-image {
      flex: 1;
      position: relative;
      transform: rotate(1deg);
      border-radius: 20px;
      overflow: hidden;
      box-shadow: 0 20px 30px rgba(0,0,0,0.15);
    }
    .hero-image img {
      width: 100%;
      object-fit: cover;
    }

    /* 功能 */
    .features-grid {
      display: grid;
      grid-template-columns: repeat(2,1fr);
      gap: 28px;
    }
    .feature-card {
      background: var(--card-bg);
      border-radius: var(--radius-md);
      padding: 28px;
      box-shadow: var(--shadow-card);
      display: flex;
      gap: 20px;
      align-items: flex-start;
      border-left: 4px solid var(--primary);
      transition: var(--transition);
    }
    .feature-card:hover {
      transform: translateY(-2px);
      box-shadow: var(--shadow-hover);
    }
    .feature-icon {
      font-size: 40px;
      color: var(--primary);
      flex-shrink: 0;
    }
    .feature-content h3 {
      font-size: 20px;
      font-weight: 600;
      margin-bottom: 8px;
      color: var(--text-primary);
    }

    /* 场景 */
    .scenario-row {
      display: flex;
      align-items: center;
      gap: 48px;
      margin-bottom: 80px;
    }
    .scenario-row.reverse {
      flex-direction: row-reverse;
    }
    .scenario-img {
      flex: 1;
      border-radius: var(--radius-lg);
      overflow: hidden;
      box-shadow: var(--shadow-card);
    }
    .scenario-text {
      flex: 1;
    }
    .tag {
      background: var(--accent);
      color: white;
      padding: 4px 12px;
      border-radius: 20px;
      font-size: 14px;
      display: inline-block;
      margin-bottom: 12px;
    }

    /* 案例墙 */
    .case-scroll {
      display: flex;
      gap: 24px;
      overflow-x: auto;
      padding-bottom: 16px;
      scrollbar-width: none;
      -ms-overflow-style: none;
    }
    .case-scroll::-webkit-scrollbar {
      display: none;
    }
    .case-card {
      min-width: 300px;
      background: white;
      border-radius: var(--radius-md);
      padding: 24px;
      box-shadow: var(--shadow-card);
      transition: var(--transition);
    }
    .case-card:hover {
      transform: scale(1.02);
    }
    .case-header {
      display: flex;
      align-items: center;
      gap: 12px;
      margin-bottom: 16px;
    }
    .avatar {
      width: 44px;
      height: 44px;
      border-radius: 50%;
      background: #ddd;
    }
    .case-data {
      font-size: 24px;
      font-weight: 700;
      color: var(--accent);
    }

    /* FAQ */
    .faq-item {
      border-bottom: 1px solid var(--border-light);
      margin-bottom: 12px;
    }
    .faq-question {
      display: flex;
      justify-content: space-between;
      align-items: center;
      padding: 20px 0;
      font-weight: 600;
      font-size: 18px;
      cursor: pointer;
      color: var(--text-primary);
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      color: var(--text-body);
      padding-right: 20px;
    }
    .faq-item.active .faq-answer {
      max-height: 120px;
      padding-bottom: 16px;
    }

    /* CTA深色区 */
    .cta-dark {
      background: var(--bg-dark);
      color: var(--text-on-dark);
      text-align: center;
    }
    .cta-form {
      display: flex;
      gap: 12px;
      justify-content: center;
      flex-wrap: wrap;
      margin-top: 30px;
    }
    .cta-form input {
      padding: 14px 16px;
      border-radius: 6px;
      background: white;
      min-width: 220px;
      font-size: 16px;
    }
    .btn-accent {
      background: var(--accent);
      color: white;
      font-weight: 600;
      padding: 14px 28px;
      border-radius: var(--radius-sm);
      cursor: pointer;
    }
    .btn-accent:hover {
      background: var(--accent-light);
    }

    footer {
      background: #f2f2ed;
      padding: 60px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 30px;
    }
    @media (max-width: 1024px) {
      .hero-grid { flex-direction: column; }
      .features-grid { grid-template-columns: 1fr; }
      .footer-grid { grid-template-columns: 1fr 1fr; }
    }
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .hamburger { display: flex; }
      .hero-text h1 { font-size: 32px; }
      section { padding: 60px 0; }
      .scenario-row, .scenario-row.reverse { flex-direction: column; }
    }