/* roulang page: index */
:root {
      --primary: #F15A24;
      --primary-dark: #D94A1A;
      --secondary: #1B2A4A;
      --secondary-light: #2C3E5A;
      --bg: #FAFAFA;
      --card-bg: #FFFFFF;
      --text: #1F2937;
      --text-secondary: #4B5563;
      --text-light: #6B7280;
      --border: #E5E7EB;
      --shadow-sm: 0 4px 12px rgba(0,0,0,0.04);
      --shadow: 0 4px 20px rgba(0,0,0,0.06);
      --shadow-lg: 0 8px 30px rgba(0,0,0,0.10);
      --radius: 12px;
      --radius-btn: 8px;
      --transition: 0.3s ease;
      --container: 1200px;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    body {
      font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
      background-color: var(--bg);
      color: var(--text);
      line-height: 1.7;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }
    .container {
      max-width: var(--container);
      margin: 0 auto;
      padding: 0 24px;
    }
    a {
      text-decoration: none;
      color: inherit;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    button, .btn {
      cursor: pointer;
      font-family: inherit;
      font-size: 16px;
      transition: var(--transition);
      border: none;
      outline: none;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      border-radius: var(--radius-btn);
      font-weight: 600;
    }
    /* 导航 */
    .header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      background: rgba(255,255,255,0.9);
      backdrop-filter: blur(10px);
      transition: var(--transition);
      border-bottom: 1px solid transparent;
    }
    .header.scrolled {
      background: rgba(255,255,255,0.98);
      box-shadow: 0 2px 12px rgba(0,0,0,0.06);
      border-bottom-color: var(--border);
    }
    .nav {
      display: flex;
      align-items: center;
      justify-content: space-between;
      padding: 16px 0;
    }
    .logo {
      display: flex;
      align-items: center;
      gap: 10px;
      font-weight: 700;
      font-size: 1.5rem;
      color: var(--secondary);
      letter-spacing: -0.3px;
    }
    .logo-icon {
      width: 32px;
      height: 32px;
      background: var(--primary);
      border-radius: 8px;
      display: flex;
      align-items: center;
      justify-content: center;
      color: white;
      font-size: 18px;
    }
    .logo small {
      font-size: 0.7rem;
      font-weight: 400;
      color: var(--text-light);
      margin-left: 5px;
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 32px;
    }
    .nav-links a {
      font-weight: 500;
      font-size: 0.95rem;
      color: var(--text-secondary);
      transition: color 0.2s;
      white-space: nowrap;
    }
    .nav-links a:hover, .nav-links a:active {
      color: var(--primary);
    }
    .menu-toggle {
      display: none;
      background: transparent;
      font-size: 1.8rem;
      color: var(--secondary);
      padding: 8px;
      border-radius: 8px;
    }
    /* 英雄区 */
    .hero {
      padding: 140px 0 100px;
      background: linear-gradient(135deg, #FAFAFA 0%, #F0F4F8 100%);
      position: relative;
      overflow: hidden;
    }
    .hero .container {
      display: flex;
      align-items: center;
      gap: 60px;
    }
    .hero-content {
      flex: 1;
    }
    .hero h1 {
      font-size: 48px;
      font-weight: 700;
      letter-spacing: -0.5px;
      color: var(--secondary);
      line-height: 1.2;
      margin-bottom: 20px;
    }
    .hero .subtitle {
      font-size: 1.25rem;
      color: var(--text-light);
      margin-bottom: 32px;
      max-width: 540px;
    }
    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .btn-primary {
      background: var(--primary);
      color: white;
      padding: 14px 32px;
      box-shadow: 0 8px 20px rgba(241,90,36,0.25);
    }
    .btn-primary:hover {
      background: var(--primary-dark);
      transform: translateY(-2px);
      box-shadow: 0 12px 28px rgba(241,90,36,0.35);
    }
    .btn-outline {
      background: transparent;
      border: 2px solid var(--secondary);
      color: var(--secondary);
      padding: 14px 32px;
    }
    .btn-outline:hover {
      background: var(--secondary);
      color: white;
    }
    .hero-image {
      flex: 1;
      border-radius: 24px;
      overflow: hidden;
      box-shadow: var(--shadow-lg);
    }
    .hero-image img {
      width: 100%;
      height: auto;
      object-fit: cover;
    }
    /* 通用板块 */
    section {
      padding: 110px 0;
    }
    .section-title {
      text-align: center;
      margin-bottom: 56px;
    }
    .section-title h2 {
      font-size: 36px;
      font-weight: 700;
      letter-spacing: -0.3px;
      color: var(--secondary);
    }
    .section-title p {
      color: var(--text-light);
      font-size: 1.1rem;
      margin-top: 12px;
    }
    /* 核心优势卡片 */
    .cards-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .card {
      background: var(--card-bg);
      border-radius: var(--radius);
      padding: 32px;
      box-shadow: var(--shadow);
      transition: var(--transition);
      display: flex;
      flex-direction: column;
    }
    .card:hover {
      box-shadow: var(--shadow-lg);
      transform: translateY(-4px);
    }
    .card-icon {
      width: 56px;
      height: 56px;
      background: rgba(241,90,36,0.1);
      border-radius: 16px;
      display: flex;
      align-items: center;
      justify-content: center;
      margin-bottom: 20px;
      color: var(--primary);
      font-size: 28px;
    }
    .card h3 {
      font-size: 22px;
      font-weight: 600;
      margin-bottom: 10px;
    }
    .card p {
      color: var(--text-secondary);
      line-height: 1.6;
    }
    /* 服务栅格 2x3 */
    .service-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .service-card {
      background: var(--card-bg);
      border-radius: var(--radius);
      padding: 32px 24px;
      box-shadow: var(--shadow);
      transition: var(--transition);
      text-align: left;
    }
    .service-card:hover {
      box-shadow: var(--shadow-lg);
      transform: translateY(-4px);
    }
    .service-card img {
      width: 100%;
      height: 140px;
      object-fit: cover;
      border-radius: 8px;
      margin-bottom: 20px;
    }
    /* 场景交替 */
    .scene-row {
      display: flex;
      align-items: center;
      gap: 80px;
      margin-bottom: 80px;
    }
    .scene-row.reverse {
      flex-direction: row-reverse;
    }
    .scene-text {
      flex: 1;
    }
    .scene-image {
      flex: 1;
      border-radius: 20px;
      overflow: hidden;
      box-shadow: var(--shadow);
    }
    .scene-image img {
      width: 100%;
      height: auto;
    }
    /* 案例卡片 */
    .case-scroll {
      display: flex;
      gap: 24px;
      overflow-x: auto;
      padding-bottom: 12px;
      scroll-snap-type: x mandatory;
    }
    .case-card {
      min-width: 280px;
      background: var(--card-bg);
      border-radius: var(--radius);
      padding: 24px;
      box-shadow: var(--shadow);
      scroll-snap-align: start;
      transition: var(--transition);
    }
    .case-card:hover {
      box-shadow: var(--shadow-lg);
    }
    .case-number {
      font-size: 2.5rem;
      font-weight: 700;
      color: var(--primary);
    }
    /* FAQ */
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
    }
    .faq-item {
      border-bottom: 1px solid var(--border);
    }
    .faq-question {
      width: 100%;
      background: transparent;
      padding: 20px 0;
      font-weight: 600;
      font-size: 1.1rem;
      display: flex;
      justify-content: space-between;
      align-items: center;
      color: var(--secondary);
      text-align: left;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease, padding 0.3s;
      color: var(--text-secondary);
    }
    .faq-item.active .faq-answer {
      max-height: 150px;
      padding-bottom: 20px;
    }
    /* CTA 带表单 */
    .cta-block {
      background: var(--secondary);
      color: white;
      text-align: center;
      padding: 80px 0;
      border-radius: 0;
    }
    .cta-block h2 {
      font-size: 2.2rem;
      font-weight: 700;
      color: white;
    }
    .inline-form {
      display: flex;
      justify-content: center;
      gap: 12px;
      margin-top: 24px;
      flex-wrap: wrap;
    }
    .inline-form input {
      padding: 14px 20px;
      border-radius: var(--radius-btn);
      border: 1px solid transparent;
      background: white;
      min-width: 260px;
      font-size: 1rem;
      outline: none;
    }
    .inline-form input:focus {
      box-shadow: 0 0 0 3px rgba(241,90,36,0.4);
    }
    /* 页脚 */
    .footer {
      background: var(--secondary);
      color: #ddd;
      padding: 60px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr;
      gap: 40px;
      margin-bottom: 40px;
    }
    .footer a {
      color: #ccc;
    }
    .footer a:hover {
      color: var(--primary);
    }
    .social-icons i {
      font-size: 1.4rem;
      margin-right: 16px;
      transition: 0.2s;
      color: #ccc;
    }
    .social-icons i:hover {
      color: var(--primary);
    }
    .copyright {
      border-top: 1px solid rgba(255,255,255,0.2);
      padding-top: 20px;
      text-align: center;
      color: #9CA3AF;
    }
    /* 响应式 */
    @media (max-width: 1024px) {
      .hero .container { flex-direction: column; }
      .cards-grid, .service-grid { grid-template-columns: repeat(2, 1fr); }
    }
    @media (max-width: 768px) {
      .nav-links { display: none; position: fixed; top: 72px; left:0; right:0; background: white; flex-direction: column; padding: 24px; gap: 20px; box-shadow: var(--shadow); }
      .nav-links.open { display: flex; }
      .menu-toggle { display: block; }
      .cards-grid, .service-grid { grid-template-columns: 1fr; }
      .hero h1 { font-size: 34px; }
      .scene-row, .scene-row.reverse { flex-direction: column; gap: 28px; }
      .footer-grid { grid-template-columns: 1fr; }
      .inline-form { flex-direction: column; align-items: center; }
    }