/* roulang page: index */
* {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    :root {
      --orange: #FF6B35;
      --orange-light: #FF8C42;
      --cyan: #00F2FE;
      --dark: #1A1A2E;
      --dark-secondary: #16213E;
      --gray-bg: #F0F2F5;
      --white: #FFFFFF;
      --text-primary: #1A1A2E;
      --text-secondary: #4A4A5A;
      --text-muted: #7A7A8A;
      --border-light: rgba(0,0,0,0.06);
      --shadow-card: 0 4px 20px rgba(0,0,0,0.04);
      --shadow-card-hover: 0 20px 40px -12px rgba(0,0,0,0.15), 0 0 0 1px rgba(0,0,0,0.03);
      --radius-xl: 24px;
      --radius-lg: 16px;
      --radius-md: 12px;
      --font-inter: 'Inter', 'PingFang SC', 'Microsoft YaHei', sans-serif;
      --transition: all 0.25s ease;
    }
    body {
      font-family: var(--font-inter);
      background-color: var(--white);
      color: var(--text-primary);
      line-height: 1.7;
      -webkit-font-smoothing: antialiased;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
    }
    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 32px;
    }
    @media (max-width: 768px) {
      .container {
        padding: 0 20px;
      }
    }
    /* 按钮基础 */
    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      font-weight: 600;
      border-radius: var(--radius-lg);
      transition: var(--transition);
      cursor: pointer;
      border: none;
      font-family: var(--font-inter);
      white-space: nowrap;
      padding: 14px 32px;
      font-size: 1rem;
    }
    .btn-primary {
      background: linear-gradient(135deg, var(--orange) 0%, var(--orange-light) 100%);
      color: white;
      box-shadow: 0 10px 20px -8px rgba(255,107,53,0.4);
    }
    .btn-primary:hover {
      transform: translateY(-2px);
      box-shadow: 0 16px 28px -8px rgba(255,107,53,0.5);
    }
    .btn-outline {
      background: transparent;
      border: 2px solid var(--cyan);
      color: var(--dark);
    }
    .btn-outline:hover {
      background: rgba(0,242,254,0.1);
    }
    .btn-ghost {
      background: transparent;
      border: 2px solid white;
      color: white;
    }
    .btn-ghost:hover {
      background: rgba(255,255,255,0.15);
    }
    .btn-white {
      background: white;
      color: var(--orange);
      font-weight: 700;
    }
    /* 导航 */
    .nav {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      padding: 16px 0;
      transition: var(--transition);
      background: transparent;
    }
    .nav.scrolled {
      background: rgba(255,255,255,0.92);
      backdrop-filter: blur(20px);
      box-shadow: 0 4px 20px rgba(0,0,0,0.05);
    }
    .nav .container {
      display: flex;
      align-items: center;
      justify-content: space-between;
    }
    .logo {
      font-weight: 800;
      font-size: 1.5rem;
      letter-spacing: -0.02em;
      color: white;
      display: flex;
      align-items: baseline;
      gap: 6px;
    }
    .nav.scrolled .logo {
      color: var(--dark);
    }
    .logo span {
      font-size: 0.75rem;
      font-weight: 500;
      opacity: 0.8;
      letter-spacing: 0;
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 32px;
      list-style: none;
    }
    .nav-links a {
      font-weight: 500;
      color: rgba(255,255,255,0.85);
      transition: var(--transition);
      font-size: 0.95rem;
    }
    .nav.scrolled .nav-links a {
      color: var(--text-secondary);
    }
    .nav-links a:hover {
      color: var(--orange);
    }
    .nav-cta {
      background: linear-gradient(135deg, var(--orange), var(--orange-light));
      color: white !important;
      padding: 10px 24px;
      border-radius: var(--radius-lg);
      font-weight: 600;
    }
    .nav.scrolled .nav-cta {
      color: white !important;
    }
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
      background: none;
      border: none;
      padding: 8px;
      z-index: 1001;
    }
    .hamburger span {
      width: 24px;
      height: 2px;
      background: white;
      transition: var(--transition);
    }
    .nav.scrolled .hamburger span {
      background: var(--dark);
    }
    @media (max-width: 1024px) {
      .nav-links {
        display: none;
      }
      .hamburger {
        display: flex;
      }
    }
    .mobile-menu {
      position: fixed;
      top: 0;
      right: 0;
      width: 80%;
      max-width: 320px;
      height: 100vh;
      background: white;
      box-shadow: -10px 0 30px rgba(0,0,0,0.1);
      transform: translateX(100%);
      transition: transform 0.3s ease;
      z-index: 1002;
      display: flex;
      flex-direction: column;
      padding: 32px;
      gap: 24px;
    }
    .mobile-menu.active {
      transform: translateX(0);
    }
    .mobile-menu a {
      font-size: 1.2rem;
      font-weight: 600;
      color: var(--dark);
      padding: 8px 0;
      border-bottom: 1px solid var(--gray-bg);
    }
    .mobile-menu .btn-primary {
      margin-top: auto;
      text-align: center;
    }
    /* Hero */
    .hero {
      background: linear-gradient(180deg, #1A1A2E 0%, #16213E 100%);
      min-height: 100vh;
      display: flex;
      align-items: center;
      padding: 120px 0 80px;
      position: relative;
      overflow: hidden;
    }
    .hero::before {
      content: '';
      position: absolute;
      width: 600px;
      height: 600px;
      background: radial-gradient(circle, rgba(255,107,53,0.15) 0%, transparent 70%);
      top: -100px;
      right: -100px;
      border-radius: 50%;
    }
    .hero-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 60px;
      align-items: center;
    }
    .hero-title {
      font-weight: 800;
      font-size: clamp(2.5rem, 6vw, 4.5rem);
      line-height: 1.1;
      letter-spacing: -0.02em;
      color: white;
      margin-bottom: 24px;
    }
    .hero-title .highlight {
      background: linear-gradient(90deg, #FF6B35 0%, #00F2FE 100%);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
    }
    .hero-desc {
      font-size: 1.2rem;
      color: rgba(255,255,255,0.7);
      margin-bottom: 32px;
      max-width: 480px;
    }
    .hero-actions {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
      margin-bottom: 48px;
    }
    .hero-stats {
      display: flex;
      gap: 32px;
      flex-wrap: wrap;
    }
    .stat-item {
      color: white;
    }
    .stat-number {
      font-family: 'Inter', sans-serif;
      font-weight: 700;
      font-size: 2rem;
      background: linear-gradient(90deg, #FF6B35, #00F2FE);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
    }
    .hero-visual img {
      border-radius: var(--radius-xl);
      box-shadow: 0 30px 50px rgba(0,0,0,0.4);
    }
    @media (max-width: 768px) {
      .hero-grid {
        grid-template-columns: 1fr;
        text-align: center;
      }
      .hero-desc {
        max-width: 100%;
        margin-left: auto;
        margin-right: auto;
      }
      .hero-actions {
        justify-content: center;
      }
      .hero-stats {
        justify-content: center;
      }
      .hero-visual {
        display: none;
      }
    }
    /* 通用板块标题 */
    .section {
      padding: 100px 0;
    }
    @media (max-width: 768px) {
      .section {
        padding: 60px 0;
      }
    }
    .section-title {
      font-weight: 700;
      font-size: clamp(2rem, 4vw, 2.8rem);
      margin-bottom: 16px;
      display: flex;
      align-items: center;
      gap: 16px;
    }
    .section-title::before {
      content: '';
      display: block;
      width: 40px;
      height: 4px;
      background: #FF6B35;
      border-radius: 2px;
    }
    .section-sub {
      color: var(--text-secondary);
      margin-bottom: 48px;
      font-size: 1.1rem;
    }
    /* 服务卡片 非对称 */
    .services-grid {
      display: grid;
      grid-template-columns: 1fr 1.2fr 1fr;
      gap: 24px;
      align-items: start;
    }
    @media (max-width: 1024px) {
      .services-grid {
        grid-template-columns: 1fr 1fr;
      }
    }
    @media (max-width: 768px) {
      .services-grid {
        grid-template-columns: 1fr;
      }
    }
    .service-card {
      background: white;
      border-radius: var(--radius-xl);
      padding: 40px 32px;
      box-shadow: var(--shadow-card);
      transition: var(--transition);
      border: 1px solid var(--border-light);
    }
    .service-card:hover {
      box-shadow: var(--shadow-card-hover);
      transform: translateY(-4px);
    }
    .service-card.featured {
      background: linear-gradient(135deg, #FF6B35 0%, #FF8C42 100%);
      color: white;
      transform: scale(1.03);
      border: none;
    }
    .service-card.featured:hover {
      transform: scale(1.03) translateY(-4px);
    }
    .service-icon {
      font-size: 2.5rem;
      margin-bottom: 20px;
    }
    .service-card h3 {
      font-weight: 600;
      font-size: 1.5rem;
      margin-bottom: 12px;
    }
    .service-card p {
      color: var(--text-secondary);
      margin-bottom: 24px;
      font-size: 0.95rem;
    }
    .service-card.featured p {
      color: rgba(255,255,255,0.85);
    }
    .service-link {
      font-weight: 600;
      color: var(--orange);
      display: inline-flex;
      align-items: center;
      gap: 4px;
    }
    .service-card.featured .service-link {
      color: white;
    }
    /* 数据优势 */
    .advantages-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
    }
    @media (max-width: 768px) {
      .advantages-grid {
        grid-template-columns: 1fr 1fr;
      }
    }
    .adv-card {
      background: var(--gray-bg);
      border-radius: var(--radius-xl);
      padding: 32px 24px;
      text-align: center;
      transition: var(--transition);
    }
    .adv-card:hover {
      background: linear-gradient(135deg, rgba(255,107,53,0.05), rgba(0,242,254,0.05));
    }
    .adv-number {
      font-family: 'Inter', sans-serif;
      font-weight: 700;
      font-size: 2.8rem;
      background: linear-gradient(90deg, #FF6B35, #00F2FE);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      margin-bottom: 8px;
    }
    /* 流程 */
    .steps-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 32px;
      position: relative;
    }
    @media (max-width: 768px) {
      .steps-grid {
        grid-template-columns: 1fr;
      }
    }
    .step-item {
      text-align: center;
      position: relative;
    }
    .step-number {
      font-size: 4rem;
      font-weight: 800;
      color: rgba(255,107,53,0.1);
      position: absolute;
      top: -30px;
      left: 50%;
      transform: translateX(-50%);
      z-index: 0;
    }
    .step-icon {
      font-size: 2.5rem;
      margin-bottom: 16px;
      position: relative;
      z-index: 1;
    }
    /* 案例卡片 */
    .cases-scroll {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 24px;
    }
    @media (max-width: 768px) {
      .cases-scroll {
        grid-template-columns: 1fr;
      }
    }
    .case-card {
      background: white;
      border-radius: var(--radius-xl);
      overflow: hidden;
      box-shadow: var(--shadow-card);
      transition: var(--transition);
    }
    .case-card:hover {
      box-shadow: var(--shadow-card-hover);
    }
    .case-img {
      height: 200px;
      background: #e0e0e0;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 700;
      color: #aaa;
    }
    .case-img img {
      width: 100%;
      height: 100%;
      object-fit: cover;
    }
    .case-content {
      padding: 24px;
    }
    .case-stat {
      color: var(--orange);
      font-weight: 700;
      font-size: 1.2rem;
    }
    /* FAQ */
    .faq-item {
      border-bottom: 1px solid var(--border-light);
      padding: 20px 0;
      cursor: pointer;
    }
    .faq-question {
      font-weight: 600;
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-size: 1.1rem;
    }
    .faq-icon {
      color: var(--orange);
      font-size: 1.4rem;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      color: var(--text-secondary);
      padding-top: 0;
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding-top: 12px;
    }
    /* CTA横幅 */
    .cta-band {
      background: linear-gradient(90deg, #FF6B35 0%, #00F2FE 100%);
      padding: 80px 0;
      text-align: center;
      color: white;
      position: relative;
    }
    .cta-band h2 {
      font-size: 2.5rem;
      margin-bottom: 16px;
    }
    /* 页脚 */
    .footer {
      background: var(--dark);
      color: rgba(255,255,255,0.7);
      padding: 60px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
    }
    @media (max-width: 768px) {
      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }
    }
    .footer-logo {
      font-weight: 800;
      font-size: 1.8rem;
      color: white;
      margin-bottom: 12px;
    }
    .footer a {
      color: rgba(255,255,255,0.6);
      display: block;
      margin-bottom: 8px;
      transition: var(--transition);
    }
    .footer a:hover {
      color: var(--orange);
    }