/* roulang page: index */
:root {
      --primary: #0F9B4E;
      --primary-deep: #0B7A3D;
      --accent: #F85C2B;
      --dark-bg: #1A1D22;
      --soft-bg: #F7F6F3;
      --white: #ffffff;
      --text-heading: #111827;
      --text-body: #374151;
      --text-muted: #6B7280;
      --border-light: #E5E7EB;
      --radius-card: 16px;
      --radius-btn: 8px;
      --shadow-sm: 0 2px 12px rgba(0,0,0,0.06);
      --shadow-md: 0 8px 28px rgba(0,0,0,0.12);
      --font-stack: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
    }

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

    body {
      font-family: var(--font-stack);
      line-height: 1.7;
      color: var(--text-body);
      background-color: var(--white);
      -webkit-font-smoothing: antialiased;
    }

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

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

    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }

    /* 导航栏 */
    .header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 72px;
      background: rgba(255,255,255,0.92);
      backdrop-filter: blur(12px);
      box-shadow: 0 4px 20px rgba(0,0,0,0.04);
      z-index: 100;
      display: flex;
      align-items: center;
    }

    .nav-container {
      display: flex;
      justify-content: space-between;
      align-items: center;
      width: 100%;
    }

    .logo {
      font-size: 24px;
      font-weight: 700;
      color: var(--primary);
      letter-spacing: 1px;
      display: flex;
      align-items: center;
      gap: 8px;
    }

    .logo-icon {
      width: 28px;
      height: 28px;
      background: var(--primary);
      mask: url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24"><circle cx="12" cy="12" r="10" fill="black"/><path d="M12 2a10 10 0 0 1 7 17H5a10 10 0 0 1 7-17z" fill="white"/></svg>') center/cover no-repeat;
      background-color: var(--primary);
    }

    .nav-menu {
      display: flex;
      gap: 36px;
      align-items: center;
      list-style: none;
    }

    .nav-menu a {
      font-size: 16px;
      font-weight: 500;
      color: var(--text-body);
      position: relative;
      padding: 6px 0;
      transition: color 0.2s;
    }

    .nav-menu a::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--primary);
      transition: width 0.25s ease;
    }

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

    .nav-menu a:hover::after {
      width: 100%;
    }

    .btn-contact {
      background: var(--accent);
      color: white;
      padding: 12px 26px;
      border-radius: 40px;
      font-weight: 600;
      transition: all 0.25s;
      box-shadow: 0 4px 12px rgba(248,92,43,0.3);
      font-size: 15px;
    }

    .btn-contact:hover {
      background: #e14a1a;
      transform: translateY(-1px);
      box-shadow: 0 8px 20px rgba(248,92,43,0.4);
    }

    .mobile-toggle {
      display: none;
      font-size: 28px;
      background: none;
      border: none;
      color: var(--text-heading);
    }

    /* Hero */
    .hero {
      background: var(--dark-bg);
      min-height: 90vh;
      display: flex;
      align-items: center;
      margin-top: 72px;
      position: relative;
      overflow: hidden;
    }

    .hero::before {
      content: '';
      position: absolute;
      width: 600px;
      height: 600px;
      background: radial-gradient(circle, rgba(15,155,78,0.18) 0%, transparent 70%);
      top: -100px;
      right: -80px;
      border-radius: 50%;
    }

    .hero .container {
      display: flex;
      align-items: center;
      gap: 48px;
      flex-wrap: wrap;
    }

    .hero-text {
      flex: 1 1 45%;
      color: white;
    }

    .hero-text h1 {
      font-size: clamp(36px, 5vw, 52px);
      font-weight: 700;
      line-height: 1.2;
      margin-bottom: 24px;
      color: white;
    }

    .hero-text p {
      font-size: 18px;
      color: #d1d5db;
      margin-bottom: 36px;
      max-width: 500px;
    }

    .btn-group {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }

    .btn-primary {
      background: var(--primary);
      color: white;
      padding: 14px 36px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      transition: 0.25s;
      box-shadow: 0 6px 18px rgba(15,155,78,0.4);
    }

    .btn-primary:hover {
      background: var(--primary-deep);
      transform: translateY(-2px);
    }

    .btn-outline {
      background: transparent;
      border: 2px solid var(--primary);
      color: var(--primary);
      padding: 14px 36px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      transition: 0.25s;
    }

    .btn-outline:hover {
      background: var(--primary);
      color: white;
    }

    .hero-img {
      flex: 1 1 45%;
      border-radius: 28px;
      overflow: hidden;
      box-shadow: 0 20px 45px rgba(0,0,0,0.4);
    }

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

    /* 公共板块 */
    section {
      padding: 100px 0;
    }

    .section-title {
      text-align: center;
      margin-bottom: 60px;
    }

    .section-title h2 {
      font-size: 36px;
      font-weight: 700;
      color: var(--text-heading);
      margin-bottom: 12px;
    }

    .section-title p {
      color: var(--text-muted);
      font-size: 18px;
    }

    /* 服务卡片 */
    .services {
      background: white;
    }

    .cards-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }

    .service-card {
      background: white;
      padding: 36px 24px;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-sm);
      transition: all 0.3s;
      border-top: 6px solid var(--primary);
    }

    .service-card:hover {
      transform: translateY(-8px);
      box-shadow: var(--shadow-md);
      border-top-color: var(--accent);
    }

    .service-icon {
      width: 64px;
      height: 64px;
      background: rgba(15,155,78,0.08);
      border-radius: 20px;
      display: flex;
      align-items: center;
      justify-content: center;
      margin-bottom: 24px;
      color: var(--primary);
      font-size: 32px;
    }

    .service-card h3 {
      font-size: 22px;
      margin-bottom: 12px;
      color: var(--text-heading);
    }

    /* 数据墙 */
    .data-wall {
      background: var(--soft-bg);
    }

    .stats {
      display: flex;
      justify-content: space-around;
      text-align: center;
      flex-wrap: wrap;
    }

    .stat-item {
      flex: 1;
      min-width: 150px;
      padding: 30px;
    }

    .stat-number {
      font-size: 48px;
      font-weight: 800;
      color: var(--primary);
    }

    .stat-label {
      color: var(--text-muted);
      font-size: 16px;
      margin-top: 8px;
    }

    /* 流程 */
    .process {
      background: white;
    }

    .steps {
      display: flex;
      justify-content: space-between;
      align-items: center;
    }

    .step {
      text-align: center;
    }

    .step-circle {
      width: 60px;
      height: 60px;
      background: var(--primary);
      color: white;
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 700;
      font-size: 24px;
      margin: 0 auto 16px;
    }

    /* 案例 */
    .cases-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 32px;
    }

    .case-card {
      border-radius: 24px;
      overflow: hidden;
      background: white;
      box-shadow: var(--shadow-sm);
      transition: 0.3s;
    }

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

    .case-img img {
      height: 260px;
      object-fit: cover;
    }

    .case-content {
      padding: 24px;
    }

    /* FAQ */
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
    }

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

    .faq-question {
      font-weight: 600;
      font-size: 20px;
      display: flex;
      justify-content: space-between;
      cursor: pointer;
      color: var(--text-heading);
    }

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

    .faq-item.active .faq-answer {
      max-height: 200px;
      padding-top: 16px;
    }

    /* CTA */
    .cta-section {
      background: linear-gradient(135deg, #0F9B4E 0%, #0B7A3D 100%);
      color: white;
      text-align: center;
    }

    .cta-section h2 {
      font-size: 36px;
      font-weight: 700;
    }

    .footer {
      background: var(--dark-bg);
      color: #9CA3AF;
      padding: 60px 0 30px;
    }

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

    @media (max-width: 992px) {
      .cards-grid { grid-template-columns: repeat(2,1fr); }
      .footer-grid { grid-template-columns: 1fr 1fr; }
    }

    @media (max-width: 768px) {
      .nav-menu { display: none; }
      .mobile-toggle { display: block; }
      .hero .container { flex-direction: column; }
      .cards-grid, .cases-grid { grid-template-columns: 1fr; }
      .stats { flex-direction: column; }
    }