/* roulang page: index */
:root {
      --primary: #0A2540;
      --primary-light: #1e3a5f;
      --accent: #FF6B35;
      --accent-hover: #e55a2b;
      --bg-white: #FFFFFF;
      --bg-light: #F8FAFC;
      --bg-gray: #EDF2F7;
      --text-body: #334155;
      --text-muted: #64748B;
      --text-dark: #1e293b;
      --border-light: #E2E8F0;
      --shadow-card: 0 4px 12px rgba(10, 37, 64, 0.06);
      --shadow-hover: 0 8px 24px rgba(10, 37, 64, 0.12);
      --radius-card: 16px;
      --radius-btn: 8px;
      --radius-icon: 12px;
      --font-sans: 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', sans-serif;
      --transition: 0.3s ease;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    body {
      font-family: var(--font-sans);
      color: var(--text-body);
      background: var(--bg-white);
      line-height: 1.75;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }
    img {
      max-width: 100%;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
    }
    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 32px;
    }
    /* 导航 */
    .nav {
      position: sticky;
      top: 0;
      z-index: 50;
      background: #FFFFFF;
      border-bottom: 1px solid transparent;
      box-shadow: 0 1px 4px rgba(10,37,64,0.04);
      height: 72px;
      display: flex;
      align-items: center;
      transition: box-shadow 0.3s;
    }
    .nav.scrolled {
      box-shadow: 0 4px 16px rgba(10,37,64,0.08);
    }
    .nav-inner {
      display: flex;
      justify-content: space-between;
      align-items: center;
      width: 100%;
    }
    .logo {
      font-size: 24px;
      font-weight: 700;
      color: var(--primary);
      letter-spacing: 1px;
    }
    .nav-menu {
      display: flex;
      gap: 32px;
      align-items: center;
    }
    .nav-menu a {
      font-size: 15px;
      color: #475569;
      font-weight: 500;
      position: relative;
      padding: 4px 0;
      transition: color 0.2s;
    }
    .nav-menu a:hover {
      color: var(--accent);
    }
    .nav-menu a::after {
      content: '';
      position: absolute;
      bottom: -2px;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--accent);
      transition: width 0.3s;
    }
    .nav-menu a:hover::after {
      width: 100%;
    }
    .btn-primary {
      background: var(--accent);
      color: white;
      border: none;
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 15px;
      cursor: pointer;
      transition: background 0.3s, box-shadow 0.3s;
      box-shadow: 0 4px 14px rgba(255,107,53,0.3);
      display: inline-block;
      text-align: center;
      min-width: 120px;
    }
    .btn-primary:hover {
      background: var(--accent-hover);
      box-shadow: 0 6px 20px rgba(255,107,53,0.45);
    }
    .btn-outline {
      background: transparent;
      border: 2px solid var(--primary);
      color: var(--primary);
      padding: 10px 26px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 15px;
      transition: 0.3s;
      display: inline-block;
      text-align: center;
    }
    .btn-outline:hover {
      background: #e8f0fe;
      border-color: var(--primary);
    }
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
      background: none;
      border: none;
      padding: 8px;
    }
    .hamburger span {
      width: 24px;
      height: 2px;
      background: var(--primary);
      border-radius: 2px;
      transition: 0.3s;
    }
    /* 区块通用 */
    section {
      padding: 90px 0;
    }
    .section-title {
      font-size: 34px;
      font-weight: 700;
      color: var(--primary);
      margin-bottom: 16px;
      line-height: 1.3;
    }
    .section-sub {
      font-size: 18px;
      color: var(--text-muted);
      margin-bottom: 48px;
    }
    /* Hero */
    .hero {
      background: linear-gradient(135deg, rgba(10,37,64,0.75) 0%, rgba(10,37,64,0.85) 100%), url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      color: white;
      min-height: 85vh;
      display: flex;
      align-items: center;
      position: relative;
    }
    .hero-content {
      max-width: 700px;
    }
    .hero h1 {
      font-size: 46px;
      font-weight: 700;
      line-height: 1.2;
      margin-bottom: 20px;
    }
    .hero p {
      font-size: 18px;
      opacity: 0.9;
      margin-bottom: 36px;
    }
    .hero-buttons {
      display: flex;
      gap: 20px;
      flex-wrap: wrap;
    }
    /* 卡片网格 */
    .grid-3, .grid-4 {
      display: grid;
      gap: 32px;
    }
    .grid-3 { grid-template-columns: repeat(3, 1fr); }
    .grid-4 { grid-template-columns: repeat(4, 1fr); }
    .card {
      background: var(--bg-white);
      border: 1px solid var(--border-light);
      border-radius: var(--radius-card);
      padding: 32px;
      box-shadow: var(--shadow-card);
      transition: var(--transition);
      display: flex;
      flex-direction: column;
    }
    .card:hover {
      box-shadow: var(--shadow-hover);
      transform: translateY(-2px);
    }
    .card-icon {
      width: 56px;
      height: 56px;
      background: rgba(255,107,53,0.1);
      border-radius: var(--radius-icon);
      display: flex;
      align-items: center;
      justify-content: center;
      margin-bottom: 20px;
      color: var(--accent);
      font-size: 26px;
    }
    .card h3 {
      font-size: 20px;
      font-weight: 600;
      margin-bottom: 12px;
      color: var(--text-dark);
    }
    .card p {
      font-size: 15px;
      color: var(--text-muted);
      line-height: 1.6;
    }
    .accent-line {
      width: 40px;
      height: 4px;
      background: var(--accent);
      margin-top: 16px;
      border-radius: 2px;
    }
    /* 解决方案图文 */
    .split {
      display: flex;
      gap: 60px;
      align-items: center;
    }
    .split-text {
      flex: 1;
    }
    .split-img {
      flex: 1;
      border-radius: var(--radius-card);
      overflow: hidden;
      box-shadow: var(--shadow-card);
    }
    /* 流程 */
    .steps {
      display: flex;
      justify-content: space-between;
      position: relative;
    }
    .step {
      text-align: center;
      flex: 1;
      position: relative;
    }
    .step-num {
      width: 48px;
      height: 48px;
      background: var(--primary);
      color: white;
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 700;
      font-size: 20px;
      margin: 0 auto 16px;
    }
    .step h4 {
      font-weight: 600;
      margin-bottom: 8px;
    }
    /* 数据卡片 */
    .stat-card {
      background: #f0f4ff;
      border-left: 4px solid var(--accent);
      padding: 24px;
      border-radius: 12px;
    }
    .stat-num {
      font-size: 38px;
      font-weight: 700;
      color: var(--accent);
    }
    /* 证言 */
    .testimonial-card {
      background: white;
      border-radius: var(--radius-card);
      padding: 28px;
      box-shadow: var(--shadow-card);
      position: relative;
    }
    .testimonial-card::before {
      content: "“";
      font-size: 48px;
      color: var(--accent);
      position: absolute;
      top: 10px;
      left: 16px;
      opacity: 0.3;
    }
    /* FAQ */
    .faq-item {
      border-bottom: 1px solid var(--border-light);
      padding: 20px 0;
    }
    .faq-question {
      font-weight: 600;
      font-size: 18px;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      color: var(--text-muted);
      font-size: 15px;
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      margin-top: 12px;
    }
    /* CTA */
    .cta-block {
      background: var(--primary);
      color: white;
      text-align: center;
    }
    /* 页脚 */
    .footer {
      background: var(--primary);
      color: #cbd5e1;
      padding: 60px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
    }
    .footer a {
      color: #cbd5e1;
      font-size: 14px;
    }
    @media (max-width: 1024px) {
      .grid-4 { grid-template-columns: repeat(2, 1fr); }
      .split { flex-direction: column; }
    }
    @media (max-width: 768px) {
      .nav-menu { display: none; }
      .hamburger { display: flex; }
      .container { padding: 0 20px; }
      .grid-3, .grid-4 { grid-template-columns: 1fr; }
      .hero h1 { font-size: 32px; }
      .section-title { font-size: 28px; }
      .steps { flex-direction: column; gap: 30px; }
      .footer-grid { grid-template-columns: 1fr; }
    }
    .mobile-menu {
      position: fixed;
      top: 72px;
      left: 0;
      width: 100%;
      background: white;
      flex-direction: column;
      padding: 24px;
      box-shadow: 0 10px 20px rgba(0,0,0,0.1);
      display: none;
      z-index: 40;
    }
    .mobile-menu.active {
      display: flex;
    }