/* roulang page: index */
:root {
      --primary: #0B5E42;
      --primary-hover: #094a35;
      --accent: #F5A623;
      --accent-light: rgba(245, 166, 35, 0.1);
      --bg: #F9FAFB;
      --dark: #1F2937;
      --text: #374151;
      --text-light: #6B7280;
      --white: #FFFFFF;
      --border: #E5E7EB;
      --radius-lg: 1.25rem;
      --radius-md: 1rem;
      --radius-sm: 0.5rem;
      --radius-full: 50px;
      --shadow-sm: 0 4px 12px rgba(0,0,0,0.04);
      --shadow-md: 0 8px 24px rgba(0,0,0,0.08);
      --transition: 0.25s ease;
      --container-max: 1200px;
      --nav-height: 72px;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    html {
      scroll-behavior: smooth;
    }
    body {
      font-family: system-ui, -apple-system, 'Segoe UI', 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', sans-serif;
      background: var(--bg);
      color: var(--text);
      line-height: 1.7;
      font-weight: 400;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: var(--transition);
    }
    button, .btn {
      cursor: pointer;
      border: none;
      background: none;
      font-family: inherit;
      font-size: 16px;
      transition: var(--transition);
    }
    .container {
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 24px;
    }
    /* 导航 */
    .nav {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: var(--nav-height);
      background: var(--white);
      box-shadow: 0 1px 0 var(--border);
      z-index: 1000;
      display: flex;
      align-items: center;
    }
    .nav .container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
    }
    .logo {
      font-size: 1.6rem;
      font-weight: 700;
      color: var(--primary);
      letter-spacing: -0.5px;
    }
    .logo span {
      color: var(--accent);
    }
    .nav-links {
      display: flex;
      gap: 2rem;
      list-style: none;
    }
    .nav-links a {
      font-weight: 500;
      color: var(--dark);
      padding: 0.25rem 0;
      border-bottom: 2px solid transparent;
    }
    .nav-links a:hover,
    .nav-links a.active {
      color: var(--primary);
      border-bottom-color: var(--accent);
    }
    .btn-primary {
      background: var(--primary);
      color: var(--white);
      padding: 0.7rem 2rem;
      border-radius: var(--radius-full);
      font-weight: 600;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 0.5rem;
      white-space: nowrap;
      box-shadow: 0 4px 10px rgba(11,94,66,0.2);
    }
    .btn-primary:hover {
      background: var(--primary-hover);
      transform: translateY(-1px);
      box-shadow: 0 8px 18px rgba(11,94,66,0.25);
    }
    .btn-outline {
      border: 2px solid var(--primary);
      color: var(--primary);
      padding: 0.65rem 2rem;
      border-radius: var(--radius-full);
      font-weight: 600;
      background: transparent;
    }
    .btn-outline:hover {
      background: rgba(11,94,66,0.05);
      border-color: var(--primary-hover);
      color: var(--primary-hover);
    }
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      background: none;
      border: none;
      cursor: pointer;
    }
    .hamburger span {
      width: 26px;
      height: 2.5px;
      background: var(--dark);
      border-radius: 2px;
      transition: 0.3s;
    }
    /* Hero */
    .hero {
      padding: calc(var(--nav-height) + 40px) 0 80px;
      background: radial-gradient(circle at 20% 30%, rgba(11,94,66,0.03) 0%, transparent 60%);
    }
    .hero-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      align-items: center;
      gap: 3rem;
    }
    .hero-content h1 {
      font-size: clamp(2rem, 5vw, 2.8rem);
      font-weight: 700;
      line-height: 1.2;
      color: var(--dark);
      margin-bottom: 1.2rem;
    }
    .hero-content .subtitle {
      font-size: 1.2rem;
      color: var(--text-light);
      margin-bottom: 2rem;
    }
    .hero-buttons {
      display: flex;
      gap: 1rem;
      flex-wrap: wrap;
    }
    .hero-image {
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      border-radius: var(--radius-lg);
      min-height: 320px;
      box-shadow: var(--shadow-md);
      position: relative;
      overflow: hidden;
    }
    .hero-image::after {
      content: "";
      position: absolute;
      inset: 0;
      background: linear-gradient(135deg, rgba(11,94,66,0.1) 0%, transparent 60%);
    }
    /* 通用板块 */
    .section {
      padding: 80px 0;
    }
    .section-title {
      text-align: center;
      margin-bottom: 3rem;
    }
    .section-title h2 {
      font-size: 2rem;
      font-weight: 700;
      color: var(--dark);
      margin-bottom: 0.5rem;
    }
    .section-title p {
      color: var(--text-light);
    }
    /* 优势卡片 */
    .cards-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 2rem;
    }
    .feature-card {
      background: var(--white);
      padding: 2rem 1.5rem;
      border-radius: var(--radius-lg);
      text-align: center;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
      border: 1px solid transparent;
    }
    .feature-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-md);
      border-color: var(--primary);
    }
    .feature-icon {
      width: 64px;
      height: 64px;
      background: rgba(11,94,66,0.08);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      margin: 0 auto 1.2rem;
      font-size: 2rem;
      color: var(--primary);
    }
    .feature-card h3 {
      font-size: 1.25rem;
      margin-bottom: 0.5rem;
      color: var(--dark);
    }
    /* 场景卡片 */
    .scene-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 2rem;
    }
    .scene-card {
      background: var(--white);
      border-radius: var(--radius-lg);
      border: 1px solid var(--border);
      overflow: hidden;
      transition: var(--transition);
      box-shadow: var(--shadow-sm);
    }
    .scene-card:hover {
      border-color: var(--primary);
      box-shadow: var(--shadow-md);
      transform: translateY(-4px);
    }
    .scene-img {
      height: 200px;
      background-size: cover;
      background-position: center;
    }
    .scene-body {
      padding: 1.5rem;
    }
    .scene-body h3 {
      font-size: 1.25rem;
      margin-bottom: 0.4rem;
      color: var(--dark);
    }
    /* 数据区块 */
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 2rem;
      text-align: center;
    }
    .stat-number {
      font-size: 2.8rem;
      font-weight: 700;
      color: var(--primary);
      line-height: 1.2;
    }
    .stat-label {
      color: var(--text-light);
      margin-top: 0.3rem;
    }
    .partner-placeholder {
      display: flex;
      justify-content: center;
      gap: 2rem;
      margin-top: 2.5rem;
    }
    .partner-block {
      width: 80px;
      height: 40px;
      background: #E5E7EB;
      border-radius: 8px;
    }
    /* 功能详情 */
    .feature-detail {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 3rem;
      align-items: center;
      margin-bottom: 4rem;
    }
    .feature-detail.reverse {
      direction: rtl;
    }
    .feature-detail.reverse .detail-text {
      direction: ltr;
    }
    .detail-text h2 {
      font-size: 1.8rem;
      margin-bottom: 1rem;
      color: var(--dark);
    }
    .detail-img {
      background-size: cover;
      background-position: center;
      border-radius: var(--radius-lg);
      min-height: 280px;
      box-shadow: var(--shadow-sm);
    }
    /* FAQ */
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
    }
    .faq-item {
      background: var(--white);
      border-radius: var(--radius-md);
      margin-bottom: 1rem;
      box-shadow: var(--shadow-sm);
      border-left: 4px solid transparent;
      transition: var(--transition);
    }
    .faq-item.active {
      border-left-color: var(--primary);
    }
    .faq-question {
      width: 100%;
      padding: 1.2rem 1.5rem;
      display: flex;
      align-items: center;
      gap: 0.8rem;
      font-weight: 600;
      color: var(--dark);
      background: transparent;
      border: none;
      text-align: left;
      font-size: 1.1rem;
      cursor: pointer;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      background: #F3F4F6;
      margin: 0 1rem 1rem;
      border-radius: 0.5rem;
      padding: 0 1rem;
    }
    .faq-item.active .faq-answer {
      max-height: 120px;
      padding: 1rem;
    }
    /* CTA */
    .cta-band {
      background: var(--primary);
      color: white;
      text-align: center;
      padding: 4rem 1.5rem;
      border-radius: var(--radius-lg);
    }
    .cta-band h2 {
      font-size: 2rem;
      margin-bottom: 1rem;
    }
    /* 页脚 */
    .footer {
      background: var(--dark);
      color: #D1D5DB;
      padding: 3rem 0 1.5rem;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 2rem;
    }
    .footer a {
      color: #D1D5DB;
    }
    .footer a:hover {
      color: var(--accent);
    }
    .copyright {
      border-top: 1px solid #374151;
      margin-top: 2rem;
      padding-top: 1.5rem;
      text-align: center;
      font-size: 0.9rem;
    }
    @media (max-width: 768px) {
      .container {
        padding: 0 20px;
      }
      .hamburger {
        display: flex;
      }
      .nav-links {
        position: fixed;
        top: var(--nav-height);
        left: 0;
        width: 100%;
        background: white;
        flex-direction: column;
        padding: 2rem;
        gap: 1.5rem;
        transform: translateY(-120%);
        opacity: 0;
        transition: 0.3s;
        box-shadow: 0 8px 20px rgba(0,0,0,0.05);
      }
      .nav-links.open {
        transform: translateY(0);
        opacity: 1;
      }
      .hero-grid,
      .feature-detail,
      .cards-grid,
      .scene-grid,
      .stats-grid,
      .footer-grid {
        grid-template-columns: 1fr;
      }
      .hero-image {
        min-height: 250px;
      }
      .section {
        padding: 60px 0;
      }
      .feature-detail.reverse {
        direction: ltr;
      }
    }