/* roulang page: index */
:root {
      --primary: #0F4C3A;
      --primary-dark: #0A2E24;
      --accent: #F5A623;
      --accent-hover: #E09510;
      --bg: #FAFBF7;
      --white: #FFFFFF;
      --text: #1A1A1A;
      --text-soft: #4A4A4A;
      --border: #E0E6DF;
      --success: #2E8B57;
      --card-shadow: 0 4px 20px rgba(15, 76, 58, 0.06);
      --card-shadow-hover: 0 8px 30px rgba(15, 76, 58, 0.12);
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-input: 6px;
      --font-stack: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", sans-serif;
      --max-width: 1200px;
      --section-gap: 120px;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    body {
      font-family: var(--font-stack);
      background-color: var(--bg);
      color: var(--text);
      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;
      transition: color 0.2s ease, background-color 0.2s ease;
    }
    .container {
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 24px;
    }
    /* 按钮体系 */
    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      font-weight: 600;
      font-size: 16px;
      letter-spacing: 0.5px;
      border-radius: var(--radius-btn);
      padding: 14px 32px;
      cursor: pointer;
      transition: all 0.2s ease;
      border: 2px solid transparent;
      min-width: 44px;
      min-height: 44px;
      text-align: center;
    }
    .btn-primary {
      background-color: var(--accent);
      color: #fff;
      border-color: var(--accent);
    }
    .btn-primary:hover {
      background-color: var(--accent-hover);
      border-color: var(--accent-hover);
      transform: translateY(-2px);
      box-shadow: 0 6px 18px rgba(245, 166, 35, 0.3);
    }
    .btn-outline {
      background: transparent;
      border: 2px solid var(--primary);
      color: var(--primary);
    }
    .btn-outline:hover {
      background-color: var(--primary);
      color: #fff;
      transform: translateY(-2px);
    }
    .btn-link {
      background: transparent;
      border: none;
      color: var(--primary);
      padding: 0;
      font-weight: 600;
      text-decoration: underline;
      text-underline-offset: 4px;
    }
    .btn-link:hover {
      font-weight: 700;
    }
    /* 导航 */
    .header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      background: var(--white);
      height: 72px;
      z-index: 100;
      box-shadow: 0 2px 12px rgba(0,0,0,0.03);
      display: flex;
      align-items: center;
    }
    .header .container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
    }
    .logo {
      font-size: 24px;
      font-weight: 700;
      color: var(--primary);
      display: flex;
      align-items: center;
      gap: 6px;
    }
    .logo span {
      color: var(--primary);
    }
    .logo::before {
      content: "▲";
      font-size: 18px;
      color: var(--accent);
      transform: rotate(0deg);
      margin-right: 4px;
    }
    .nav-menu {
      display: flex;
      align-items: center;
      gap: 32px;
    }
    .nav-menu a {
      color: var(--text-soft);
      font-weight: 500;
      padding: 8px 0;
      border-bottom: 3px solid transparent;
      transition: all 0.2s;
    }
    .nav-menu a:hover,
    .nav-menu a.active {
      color: var(--primary);
      border-bottom-color: var(--primary);
    }
    .hamburger {
      display: none;
      background: none;
      border: none;
      font-size: 28px;
      color: var(--primary);
      cursor: pointer;
      padding: 8px;
    }
    .mobile-menu {
      display: none;
      position: fixed;
      top: 72px;
      left: 0;
      width: 100%;
      background: var(--white);
      flex-direction: column;
      padding: 24px;
      gap: 24px;
      box-shadow: 0 10px 20px rgba(0,0,0,0.05);
      z-index: 99;
    }
    .mobile-menu a {
      font-size: 18px;
      font-weight: 500;
      color: var(--text);
      border-bottom: 1px solid var(--border);
      padding-bottom: 12px;
    }
    .mobile-menu .btn-primary {
      margin-top: 12px;
      width: fit-content;
    }
    /* Hero */
    .hero {
      padding: 160px 0 100px;
      background: linear-gradient(135deg, #FAFBF7 0%, #f0f5ed 100%);
    }
    .hero .container {
      display: flex;
      align-items: center;
      gap: 60px;
    }
    .hero-content {
      flex: 1;
    }
    .hero-content h1 {
      font-size: 44px;
      font-weight: 700;
      line-height: 1.2;
      color: var(--primary-dark);
      margin-bottom: 24px;
    }
    .hero-content .subtitle {
      font-size: 18px;
      color: var(--text-soft);
      margin-bottom: 36px;
      max-width: 550px;
    }
    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .hero-image {
      flex: 1;
      border-radius: var(--radius-card);
      overflow: hidden;
      box-shadow: var(--card-shadow);
    }
    .hero-image img {
      width: 100%;
      height: auto;
      object-fit: cover;
    }
    /* 通用板块 */
    .section {
      padding: var(--section-gap) 0;
    }
    .section-title {
      text-align: center;
      margin-bottom: 16px;
    }
    .section-title h2 {
      font-size: 32px;
      font-weight: 600;
      color: var(--primary-dark);
    }
    .section-subtitle {
      text-align: center;
      color: var(--text-soft);
      margin-bottom: 48px;
      font-size: 17px;
    }
    /* 优势数据 */
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
    }
    .stat-card {
      background: var(--white);
      border-radius: var(--radius-card);
      padding: 32px 24px;
      text-align: center;
      box-shadow: var(--card-shadow);
      transition: transform 0.2s, box-shadow 0.2s;
    }
    .stat-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--card-shadow-hover);
    }
    .stat-number {
      font-size: 44px;
      font-weight: 700;
      color: var(--accent);
      margin-bottom: 8px;
    }
    .stat-label {
      font-size: 16px;
      color: var(--text-soft);
    }
    /* 服务卡片 2x3 */
    .services-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .service-card {
      background: var(--white);
      border-radius: var(--radius-card);
      padding: 32px 28px;
      box-shadow: var(--card-shadow);
      transition: all 0.25s ease;
      display: flex;
      flex-direction: column;
      align-items: flex-start;
    }
    .service-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--card-shadow-hover);
    }
    .service-icon {
      width: 64px;
      height: 64px;
      background: rgba(15, 76, 58, 0.08);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      margin-bottom: 20px;
      transition: transform 0.3s ease;
    }
    .service-card:hover .service-icon {
      transform: rotate(5deg);
    }
    .service-icon img {
      width: 36px;
      height: 36px;
    }
    .service-card h3 {
      font-size: 20px;
      font-weight: 600;
      margin-bottom: 12px;
    }
    .service-card p {
      color: var(--text-soft);
      font-size: 15px;
      line-height: 1.6;
    }
    /* 案例 */
    .cases-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
      margin-bottom: 40px;
    }
    .case-logo {
      background: var(--white);
      border-radius: var(--radius-card);
      padding: 24px;
      display: flex;
      align-items: center;
      justify-content: center;
      filter: grayscale(100%);
      opacity: 0.8;
      transition: all 0.3s;
      box-shadow: var(--card-shadow);
    }
    .case-logo:hover {
      filter: grayscale(0%);
      opacity: 1;
    }
    .case-highlight {
      display: flex;
      gap: 24px;
      flex-wrap: wrap;
    }
    .case-card {
      background: var(--white);
      border-radius: var(--radius-card);
      padding: 28px;
      flex: 1;
      min-width: 240px;
      box-shadow: var(--card-shadow);
    }
    .case-card strong {
      display: block;
      font-size: 24px;
      color: var(--success);
      margin-bottom: 8px;
    }
    /* 流程 */
    .process-steps {
      display: flex;
      justify-content: space-between;
      align-items: flex-start;
      gap: 16px;
      position: relative;
    }
    .process-step {
      flex: 1;
      text-align: center;
      position: relative;
    }
    .step-circle {
      width: 56px;
      height: 56px;
      background: var(--primary);
      color: #fff;
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 700;
      font-size: 24px;
      margin: 0 auto 16px;
    }
    .process-step h4 {
      font-weight: 600;
      margin-bottom: 8px;
    }
    .process-arrow {
      position: absolute;
      top: 28px;
      right: -20px;
      color: var(--border);
      font-size: 24px;
    }
    /* FAQ */
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
    }
    .faq-item {
      border-bottom: 1px solid var(--border);
    }
    .faq-question {
      width: 100%;
      background: none;
      border: none;
      padding: 20px 16px;
      text-align: left;
      font-weight: 600;
      font-size: 18px;
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
      color: var(--text);
      transition: background 0.2s;
    }
    .faq-question:hover {
      background: #f4f7f2;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      background: #F4F7F2;
      padding: 0 16px;
    }
    .faq-answer p {
      padding: 16px 0;
      color: var(--text-soft);
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
    }
    .faq-item.active .faq-question {
      color: var(--primary);
    }
    /* CTA */
    .cta-section {
      background: var(--primary-dark);
      color: #fff;
      text-align: center;
      padding: 100px 0;
      background-image: radial-gradient(circle at 20% 30%, rgba(255,255,255,0.05) 0%, transparent 40%);
    }
    .cta-section h2 {
      font-size: 36px;
      margin-bottom: 20px;
    }
    .cta-section .btn-primary {
      margin-top: 32px;
      font-size: 18px;
      padding: 16px 40px;
    }
    /* 页脚 */
    .footer {
      background: var(--primary-dark);
      color: #ddd;
      padding: 60px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 32px;
      margin-bottom: 40px;
    }
    .footer h4 {
      color: #fff;
      margin-bottom: 16px;
    }
    .footer a {
      color: #ccc;
      display: block;
      margin-bottom: 8px;
    }
    .footer a:hover {
      color: var(--accent);
    }
    .copyright {
      border-top: 1px solid rgba(255,255,255,0.15);
      padding-top: 24px;
      text-align: center;
      font-size: 14px;
      color: #aaa;
    }
    /* 响应式 */
    @media (max-width: 1024px) {
      .stats-grid { grid-template-columns: repeat(2, 1fr); }
      .services-grid { grid-template-columns: repeat(2, 1fr); }
      .cases-grid { grid-template-columns: repeat(3, 1fr); }
    }
    @media (max-width: 768px) {
      .nav-menu { display: none; }
      .hamburger { display: block; }
      .mobile-menu.active { display: flex; }
      .hero .container { flex-direction: column; text-align: center; }
      .hero-content h1 { font-size: 36px; }
      .hero-buttons { justify-content: center; }
      .stats-grid { grid-template-columns: 1fr; }
      .services-grid { grid-template-columns: 1fr; }
      .cases-grid { grid-template-columns: repeat(2, 1fr); }
      .process-steps { flex-direction: column; align-items: center; }
      .process-arrow { display: none; }
      .footer-grid { grid-template-columns: 1fr 1fr; }
      :root { --section-gap: 80px; }
      .section { padding: 80px 0; }
    }
    @media (max-width: 520px) {
      .footer-grid { grid-template-columns: 1fr; }
      .case-highlight { flex-direction: column; }
    }