/* roulang page: index */
:root {
      --primary: #1A5F7A;
      --primary-dark: #134b61;
      --accent: #F28C38;
      --accent-hover: #E07B2C;
      --bg: #F8FAFC;
      --card-bg: #FFFFFF;
      --text: #1E293B;
      --text-secondary: #64748B;
      --border: #E2E8F0;
      --success: #10B981;
      --radius: 12px;
      --radius-sm: 8px;
      --shadow: 0 4px 16px rgba(0,0,0,0.04);
      --shadow-hover: 0 8px 24px rgba(0,0,0,0.08);
      --font: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
      --max-width: 1200px;
      --header-height: 64px;
      --bottom-nav-height: 56px;
    }

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

    body {
      font-family: var(--font);
      background-color: var(--bg);
      color: var(--text);
      line-height: 1.7;
      font-size: 1rem;
      -webkit-font-smoothing: antialiased;
    }

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

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

    button, input, textarea {
      font-family: inherit;
    }

    .container {
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 24px;
    }

    /* 导航 PC */
    .main-header {
      position: sticky;
      top: 0;
      z-index: 50;
      background: white;
      height: var(--header-height);
      display: flex;
      align-items: center;
      border-bottom: 1px solid var(--border);
      box-shadow: 0 1px 4px rgba(0,0,0,0.02);
    }

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

    .logo {
      font-size: 1.5rem;
      font-weight: 800;
      color: var(--primary);
      letter-spacing: -0.02em;
      white-space: nowrap;
    }

    .nav-links {
      display: flex;
      gap: 28px;
    }

    .nav-links a {
      font-size: 0.95rem;
      font-weight: 500;
      color: var(--text);
      position: relative;
      padding: 6px 0;
      transition: color 0.2s;
    }

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

    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: -4px;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--accent);
      transition: width 0.2s;
    }

    .nav-links a:hover::after,
    .nav-links a.active::after {
      width: 100%;
    }

    /* 移动端底部导航 */
    .bottom-nav {
      display: none;
      position: fixed;
      bottom: 0;
      left: 0;
      right: 0;
      background: white;
      height: var(--bottom-nav-height);
      box-shadow: 0 -2px 10px rgba(0,0,0,0.04);
      z-index: 60;
      justify-content: space-around;
      align-items: center;
      border-top: 1px solid var(--border);
    }

    .bottom-nav a {
      display: flex;
      flex-direction: column;
      align-items: center;
      font-size: 0.7rem;
      color: var(--text-secondary);
      gap: 4px;
      transition: color 0.2s;
    }

    .bottom-nav a i {
      font-size: 1.2rem;
    }

    .bottom-nav a.active {
      color: var(--accent);
    }

    /* 区块通用 */
    section {
      padding: 80px 0;
    }

    @media (max-width: 768px) {
      section {
        padding: 48px 16px;
      }
      .container {
        padding: 0 16px;
      }
    }

    /* Hero */
    .hero {
      background: linear-gradient(rgba(26,95,122,0.65), rgba(26,95,122,0.75)), url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      min-height: 80vh;
      display: flex;
      align-items: center;
      justify-content: center;
      text-align: center;
      color: white;
    }

    .hero h1 {
      font-size: 2.75rem;
      font-weight: 800;
      letter-spacing: -0.02em;
      line-height: 1.2;
      margin-bottom: 20px;
    }

    .hero p {
      font-size: 1.2rem;
      margin-bottom: 32px;
      opacity: 0.9;
    }

    .btn {
      display: inline-block;
      background: var(--accent);
      color: white;
      font-weight: 600;
      padding: 14px 32px;
      border-radius: var(--radius-sm);
      border: none;
      cursor: pointer;
      transition: background 0.2s, transform 0.2s;
      font-size: 1rem;
    }

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

    .btn-outline {
      background: transparent;
      border: 1px solid white;
      margin-left: 12px;
    }

    .btn-outline:hover {
      background: rgba(255,255,255,0.1);
    }

    /* 卡片 */
    .card {
      background: var(--card-bg);
      border-radius: var(--radius);
      box-shadow: var(--shadow);
      transition: all 0.25s ease;
      overflow: hidden;
    }

    .card:hover {
      box-shadow: var(--shadow-hover);
      transform: translateY(-2px);
    }

    .card-img {
      height: 200px;
      object-fit: cover;
      width: 100%;
    }

    .card-body {
      padding: 20px;
    }

    .card-body h3 {
      font-size: 1.25rem;
      font-weight: 600;
      margin-bottom: 8px;
    }

    /* 解决方案图文交替 */
    .solution-row {
      display: flex;
      align-items: center;
      gap: 48px;
      margin-bottom: 60px;
    }

    .solution-row.reverse {
      flex-direction: row-reverse;
    }

    .solution-img {
      flex: 1;
      border-radius: var(--radius);
      overflow: hidden;
    }

    .solution-img img {
      width: 100%;
      height: 300px;
      object-fit: cover;
    }

    .solution-text {
      flex: 1;
    }

    /* 统计数字 */
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(3,1fr);
      gap: 24px;
      text-align: center;
    }

    .stat-number {
      font-size: 2.5rem;
      font-weight: 800;
      color: var(--success);
    }

    /* FAQ */
    .faq-item {
      background: var(--card-bg);
      border-radius: var(--radius-sm);
      margin-bottom: 12px;
      box-shadow: var(--shadow);
    }

    .faq-question {
      padding: 16px;
      font-weight: 600;
      display: flex;
      justify-content: space-between;
      cursor: pointer;
      background: none;
      border: none;
      width: 100%;
      text-align: left;
      font-size: 1rem;
    }

    .faq-answer {
      padding: 0 16px 16px;
      color: var(--text-secondary);
      display: none;
    }

    .faq-item.open .faq-answer {
      display: block;
    }

    /* 表单 */
    .contact-form {
      max-width: 480px;
      margin: 0 auto;
    }

    .contact-form input,
    .contact-form textarea {
      width: 100%;
      padding: 12px 16px;
      border: 1px solid var(--border);
      border-radius: var(--radius-sm);
      margin-bottom: 16px;
      transition: border 0.2s, box-shadow 0.2s;
    }

    .contact-form input:focus,
    .contact-form textarea:focus {
      border-color: var(--primary);
      box-shadow: 0 0 0 3px rgba(26,95,122,0.2);
      outline: none;
    }

    footer {
      background: #1E293B;
      color: #CBD5E1;
      padding: 40px 0;
    }

    .footer-grid {
      display: flex;
      justify-content: space-between;
      align-items: center;
      flex-wrap: wrap;
    }

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

    @media (max-width: 768px) {
      .main-header .nav-links { display: none; }
      .bottom-nav { display: flex; }
      .hero h1 { font-size: 2rem; }
      .solution-row, .solution-row.reverse { flex-direction: column; }
      .stats-grid { grid-template-columns: 1fr; }
      .footer-grid { flex-direction: column; text-align: center; gap: 16px; }
    }