/* roulang page: index */
:root {
      --primary: #1E6FFF;
      --primary-dark: #1557D8;
      --accent: #FF6B35;
      --accent-hover: #E55A2B;
      --bg: #F8FAFC;
      --white: #FFFFFF;
      --text: #1E293B;
      --text-secondary: #475569;
      --muted: #64748B;
      --border: #E2E8F0;
      --success: #10B981;
      --shadow-sm: 0 4px 12px rgba(0,0,0,0.04), 0 1px 2px rgba(0,0,0,0.06);
      --shadow-md: 0 8px 24px rgba(0,0,0,0.08);
      --radius: 12px;
      --transition: 0.25s ease;
      --font-stack: 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', system-ui, -apple-system, sans-serif;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    body {
      font-family: var(--font-stack);
      background: var(--bg);
      color: var(--text);
      line-height: 1.5;
      -webkit-font-smoothing: antialiased;
      overflow-x: hidden;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: var(--transition);
    }
    button, input, textarea {
      font-family: inherit;
    }
    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 20px;
    }
    @media (max-width: 640px) {
      .container {
        padding: 0 16px;
      }
    }

    /* 导航 */
    .nav {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 64px;
      background: rgba(255,255,255,0.95);
      backdrop-filter: blur(12px);
      box-shadow: 0 2px 8px rgba(0,0,0,0.03);
      z-index: 50;
      display: flex;
      align-items: center;
      border-bottom: 1px solid var(--border);
    }
    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 20px;
    }
    .logo {
      display: flex;
      align-items: center;
      gap: 6px;
      font-weight: 700;
      font-size: 22px;
      color: var(--primary);
      letter-spacing: -0.3px;
    }
    .logo .dot {
      width: 12px;
      height: 12px;
      background: var(--accent);
      border-radius: 50%;
      margin-left: 4px;
      box-shadow: 0 0 0 2px rgba(255,107,53,0.2);
    }
    .logo small {
      font-size: 14px;
      font-weight: 500;
      color: var(--muted);
      margin-left: 6px;
      letter-spacing: 0.2px;
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 28px;
      list-style: none;
    }
    .nav-links a {
      font-size: 15px;
      font-weight: 500;
      color: var(--text);
      transition: color 0.2s;
    }
    .nav-links a:hover {
      color: var(--primary);
    }
    .btn-nav {
      background: var(--accent);
      color: white !important;
      padding: 10px 24px;
      border-radius: 40px;
      font-weight: 600;
      font-size: 14px;
      box-shadow: 0 4px 10px rgba(255,107,53,0.25);
    }
    .btn-nav:hover {
      background: var(--accent-hover);
      transform: translateY(-1px);
    }
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
      background: none;
      border: none;
      padding: 8px;
    }
    .hamburger span {
      width: 24px;
      height: 2.5px;
      background: var(--text);
      border-radius: 4px;
      transition: 0.3s;
    }
    @media (max-width: 1024px) {
      .nav-links {
        gap: 20px;
      }
    }
    @media (max-width: 768px) {
      .hamburger {
        display: flex;
        z-index: 55;
      }
      .nav-links {
        position: fixed;
        top: 0;
        right: -100%;
        width: 75%;
        max-width: 300px;
        height: 100vh;
        background: white;
        flex-direction: column;
        justify-content: center;
        align-items: center;
        gap: 32px;
        box-shadow: -8px 0 24px rgba(0,0,0,0.08);
        transition: right 0.35s ease;
        z-index: 54;
        padding: 40px 20px;
      }
      .nav-links.active {
        right: 0;
      }
      .nav-links a {
        font-size: 20px;
        font-weight: 600;
      }
      .btn-nav {
        padding: 14px 32px;
        font-size: 16px;
      }
    }

    /* Hero */
    .hero {
      padding: 140px 0 90px;
      background: linear-gradient(135deg, #FFFFFF 0%, #EEF2FF 100%);
      position: relative;
      overflow: hidden;
    }
    .hero-grid {
      display: flex;
      align-items: center;
      gap: 60px;
    }
    .hero-content {
      flex: 1;
      animation: fadeUp 0.8s ease;
    }
    .hero-content h1 {
      font-size: 44px;
      font-weight: 700;
      line-height: 1.2;
      color: #0F172A;
      margin-bottom: 20px;
    }
    .hero-content p {
      font-size: 18px;
      color: var(--text-secondary);
      margin-bottom: 32px;
      max-width: 480px;
    }
    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 14px 32px;
      border-radius: var(--radius);
      font-weight: 600;
      font-size: 16px;
      transition: var(--transition);
      cursor: pointer;
      border: none;
    }
    .btn-primary {
      background: var(--primary);
      color: white;
      box-shadow: 0 6px 18px rgba(30,111,255,0.3);
    }
    .btn-primary:hover {
      background: var(--primary-dark);
      transform: scale(1.03);
    }
    .btn-outline {
      background: transparent;
      border: 2px solid var(--primary);
      color: var(--primary);
    }
    .btn-outline:hover {
      background: var(--primary);
      color: white;
    }
    .hero-image {
      flex: 1;
      position: relative;
      background: linear-gradient(135deg, rgba(30,111,255,0.08) 0%, rgba(30,111,255,0.02) 100%);
      border-radius: 32px;
      overflow: hidden;
      transform: rotate(0.5deg);
      box-shadow: var(--shadow-md);
    }
    .hero-image img {
      width: 100%;
      height: auto;
      object-fit: cover;
    }
    @media (max-width: 768px) {
      .hero-grid {
        flex-direction: column;
        gap: 48px;
      }
      .hero-content h1 {
        font-size: 32px;
      }
    }

    @keyframes fadeUp {
      0% { opacity: 0; transform: translateY(20px); }
      100% { opacity: 1; transform: translateY(0); }
    }

    /* 通用区块 */
    section {
      padding: 80px 0;
    }
    @media (max-width: 640px) {
      section {
        padding: 60px 0;
      }
    }
    .section-title {
      text-align: center;
      margin-bottom: 48px;
    }
    .section-title h2 {
      font-size: 32px;
      font-weight: 700;
      color: var(--text);
      margin-bottom: 12px;
    }
    .section-title p {
      color: var(--muted);
      font-size: 16px;
    }

    /* 服务卡片 */
    .cards-grid {
      display: grid;
      grid-template-columns: repeat(3,1fr);
      gap: 28px;
    }
    .card {
      background: var(--white);
      padding: 32px 24px;
      border-radius: var(--radius);
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
      text-align: center;
    }
    .card:hover {
      box-shadow: var(--shadow-md);
      transform: translateY(-6px);
    }
    .card-icon {
      width: 64px;
      height: 64px;
      background: #EEF2FF;
      border-radius: 50%;
      margin: 0 auto 20px;
      display: flex;
      align-items: center;
      justify-content: center;
      transition: 0.3s;
    }
    .card:hover .card-icon {
      background: var(--accent);
    }
    .card h3 {
      font-size: 20px;
      font-weight: 600;
      margin-bottom: 12px;
    }
    .card p {
      color: var(--muted);
      font-size: 15px;
    }
    @media (max-width: 768px) {
      .cards-grid {
        grid-template-columns: 1fr;
      }
    }

    /* 优势数据 */
    .advantages-bg {
      background: #F1F5F9;
    }
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4,1fr);
      gap: 24px;
      text-align: center;
    }
    .stat-number {
      font-size: 40px;
      font-weight: 700;
      color: var(--primary);
    }
    .stat-label {
      color: var(--muted);
      margin-top: 6px;
    }
    @media (max-width: 640px) {
      .stats-grid {
        grid-template-columns: repeat(2,1fr);
      }
    }

    /* 案例 */
    .cases-grid {
      display: grid;
      grid-template-columns: repeat(2,1fr);
      gap: 28px;
    }
    .case-card {
      background: white;
      border-radius: var(--radius);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
      display: flex;
      transition: var(--transition);
    }
    .case-card:hover {
      box-shadow: var(--shadow-md);
      transform: translateY(-4px);
    }
    .case-img {
      width: 45%;
      background: #E2E8F0;
    }
    .case-img img {
      width: 100%;
      height: 100%;
      object-fit: cover;
    }
    .case-info {
      padding: 28px;
      display: flex;
      flex-direction: column;
      justify-content: center;
    }
    .case-info h4 {
      font-size: 20px;
      font-weight: 600;
    }
    .case-info p {
      color: var(--muted);
      margin: 8px 0 12px;
    }
    .badge {
      background: var(--accent);
      color: white;
      padding: 4px 12px;
      border-radius: 20px;
      font-size: 12px;
      font-weight: 600;
      display: inline-block;
      width: fit-content;
    }
    @media (max-width: 768px) {
      .cases-grid {
        grid-template-columns: 1fr;
      }
      .case-card {
        flex-direction: column;
      }
      .case-img {
        width: 100%;
        height: 180px;
      }
    }

    /* 流程 */
    .process-steps {
      display: flex;
      justify-content: space-between;
      align-items: center;
      text-align: center;
      gap: 24px;
    }
    .step {
      flex: 1;
      position: relative;
    }
    .step-circle {
      width: 72px;
      height: 72px;
      background: rgba(30,111,255,0.08);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 28px;
      font-weight: 700;
      color: var(--primary);
      margin: 0 auto 16px;
    }
    .step h4 {
      font-weight: 600;
    }
    @media (max-width: 640px) {
      .process-steps {
        flex-direction: column;
      }
    }

    /* 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: 18px 8px;
      font-size: 17px;
      font-weight: 600;
      text-align: left;
      display: flex;
      justify-content: space-between;
      cursor: pointer;
      color: var(--text);
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.35s ease, padding 0.3s;
      background: #F8FAFC;
      border-radius: 8px;
      padding: 0 12px;
      color: var(--text-secondary);
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding: 16px 12px;
      margin-bottom: 12px;
      border-left: 3px solid var(--primary);
    }

    /* CTA 横幅 */
    .cta-band {
      background: linear-gradient(135deg, #1E6FFF 0%, #3B82F6 100%);
      padding: 70px 0;
      text-align: center;
      color: white;
    }
    .cta-band h2 {
      font-size: 34px;
      margin-bottom: 20px;
    }
    .btn-cta {
      background: var(--accent);
      color: white;
      padding: 16px 40px;
      font-size: 18px;
      border-radius: 40px;
      font-weight: 700;
      display: inline-block;
      margin-top: 16px;
    }
    .btn-cta:hover {
      background: var(--accent-hover);
      transform: scale(1.05);
    }

    /* 联系 */
    .contact-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 40px;
    }
    .contact-form input, .contact-form textarea {
      width: 100%;
      padding: 14px;
      border: 1px solid var(--border);
      border-radius: 10px;
      margin-bottom: 16px;
      font-size: 16px;
      transition: 0.2s;
    }
    .contact-form input:focus, .contact-form textarea:focus {
      border-color: var(--primary);
      box-shadow: 0 0 0 3px rgba(30,111,255,0.15);
      outline: none;
    }
    .btn-submit {
      background: var(--primary);
      color: white;
      border: none;
      padding: 14px 28px;
      border-radius: 10px;
      font-weight: 600;
      width: 100%;
      cursor: pointer;
    }
    .contact-info {
      background: #F8FAFC;
      padding: 32px;
      border-radius: var(--radius);
    }
    @media (max-width: 768px) {
      .contact-grid {
        grid-template-columns: 1fr;
      }
    }

    footer {
      background: #1E293B;
      color: #94A3B8;
      text-align: center;
      padding: 28px 0;
      font-size: 14px;
    }