/* roulang page: index */
/* ----- 设计变量 & Reset ----- */
    :root {
      --primary-red: #E53E3E;
      --primary-red-hover: #C53030;
      --deep-blue: #1A202C;
      --deep-blue-light: #2D3748;
      --gold: #D69E2E;
      --gold-light: #ECC94B;
      --bg-light: #F7FAFC;
      --bg-blueish: #EBF8FF;
      --white: #FFFFFF;
      --text-dark: #1A202C;
      --text-body: #4A5568;
      --text-muted: #718096;
      --border-light: #E2E8F0;
      --shadow-sm: 0 4px 12px rgba(0, 0, 0, 0.04);
      --shadow-md: 0 8px 24px rgba(0, 0, 0, 0.08);
      --radius-card: 12px;
      --radius-btn: 8px;
      --transition: all 0.25s ease;
    }
    * {
      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-light);
      color: var(--text-body);
      line-height: 1.75;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: var(--transition);
    }
    ul {
      list-style: none;
    }
    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 20px;
    }
    h1, h2, h3, h4 {
      color: var(--text-dark);
      font-weight: 700;
    }
    h1 {
      font-size: 48px;
      line-height: 1.2;
      letter-spacing: -0.5px;
      font-weight: 800;
    }
    h2 {
      font-size: 36px;
      line-height: 1.3;
      margin-bottom: 16px;
    }
    h3 {
      font-size: 24px;
      font-weight: 600;
      line-height: 1.4;
    }
    /* 按钮系统 */
    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      font-weight: 600;
      border-radius: var(--radius-btn);
      transition: var(--transition);
      cursor: pointer;
      border: none;
      font-size: 16px;
      padding: 14px 32px;
      text-align: center;
    }
    .btn-primary {
      background-color: var(--primary-red);
      color: var(--white);
      box-shadow: 0 4px 10px rgba(229, 62, 62, 0.3);
    }
    .btn-primary:hover {
      background-color: var(--primary-red-hover);
      transform: translateY(-1px);
      box-shadow: 0 8px 18px rgba(229, 62, 62, 0.4);
    }
    .btn-outline {
      background: transparent;
      border: 2px solid var(--primary-red);
      color: var(--primary-red);
    }
    .btn-outline:hover {
      background: var(--primary-red);
      color: white;
    }
    .btn-gold {
      background-color: var(--gold);
      color: var(--deep-blue);
      font-weight: 700;
    }
    .btn-gold:hover {
      background-color: var(--gold-light);
    }
    .btn-white {
      background: white;
      color: var(--primary-red);
      font-weight: 700;
    }
    .btn-white:hover {
      background: #EDF2F7;
    }
    /* 导航 */
    .navbar {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      background: rgba(26, 32, 44, 0.88);
      backdrop-filter: blur(12px);
      z-index: 1000;
      padding: 14px 0;
      box-shadow: 0 4px 20px rgba(0,0,0,0.2);
    }
    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 20px;
    }
    .logo {
      font-size: 28px;
      font-weight: 800;
      color: white;
      letter-spacing: -0.5px;
    }
    .logo span {
      color: var(--primary-red);
    }
    .nav-menu {
      display: flex;
      align-items: center;
      gap: 32px;
    }
    .nav-link {
      color: rgba(255,255,255,0.85);
      font-weight: 500;
      font-size: 15px;
      position: relative;
      padding: 4px 0;
    }
    .nav-link:hover, .nav-link.active {
      color: white;
    }
    .nav-link::after {
      content: '';
      position: absolute;
      bottom: -4px;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--primary-red);
      transition: width 0.3s;
    }
    .nav-link:hover::after, .nav-link.active::after {
      width: 100%;
    }
    .hamburger {
      display: none;
      font-size: 24px;
      color: white;
      cursor: pointer;
    }
    /* Hero */
    .hero {
      background: linear-gradient(135deg, #1A202C 0%, #2D3748 100%);
      padding: 140px 0 100px;
      color: white;
    }
    .hero-grid {
      display: flex;
      align-items: center;
      gap: 60px;
    }
    .hero-text {
      flex: 1;
    }
    .hero-text h1 {
      color: white;
      margin-bottom: 24px;
    }
    .hero-text h1 span {
      color: var(--primary-red);
    }
    .hero-sub {
      font-size: 18px;
      color: rgba(255,255,255,0.8);
      margin-bottom: 36px;
      line-height: 1.7;
    }
    .hero-actions {
      display: flex;
      align-items: center;
      gap: 24px;
      flex-wrap: wrap;
    }
    .hero-image {
      flex: 1;
      background: rgba(255,255,255,0.05);
      border-radius: 24px;
      padding: 20px;
      backdrop-filter: blur(10px);
      box-shadow: 0 20px 40px rgba(0,0,0,0.4);
    }
    .hero-image img {
      border-radius: 16px;
      width: 100%;
    }
    /* 通用区块 */
    .section {
      padding: 90px 0;
    }
    .section-header {
      text-align: center;
      margin-bottom: 60px;
    }
    .section-header p {
      color: var(--text-muted);
      font-size: 18px;
      max-width: 700px;
      margin: 0 auto;
    }
    /* 功能卡片网格 */
    .features-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 30px;
    }
    .feature-card {
      background: white;
      padding: 32px;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
    }
    .feature-card:hover {
      box-shadow: var(--shadow-md);
      transform: translateY(-5px);
    }
    .feature-icon {
      font-size: 36px;
      color: var(--primary-red);
      margin-bottom: 20px;
    }
    .feature-card h3 {
      margin-bottom: 12px;
    }
    /* 场景图文混排 */
    .scene-row {
      display: flex;
      align-items: center;
      gap: 60px;
      margin-bottom: 80px;
    }
    .scene-row.reverse {
      flex-direction: row-reverse;
    }
    .scene-img {
      flex: 1;
      background: #EBF8FF;
      border-radius: 20px;
      overflow: hidden;
    }
    .scene-img img {
      width: 100%;
      height: auto;
    }
    .scene-text {
      flex: 1;
    }
    .scene-text h3 {
      margin-bottom: 16px;
    }
    /* 案例卡片 */
    .cases-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 30px;
    }
    .case-card {
      background: white;
      padding: 32px;
      border-radius: var(--radius-card);
      text-align: center;
      box-shadow: var(--shadow-sm);
    }
    .case-number {
      font-size: 48px;
      font-weight: 800;
      color: var(--primary-red);
      line-height: 1.2;
    }
    /* FAQ */
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
    }
    .faq-item {
      background: white;
      border-radius: 12px;
      margin-bottom: 16px;
      box-shadow: var(--shadow-sm);
    }
    .faq-question {
      padding: 20px 28px;
      font-weight: 600;
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
      color: var(--deep-blue);
    }
    .faq-answer {
      padding: 0 28px 20px;
      color: var(--text-body);
      display: none;
    }
    .faq-item.active .faq-answer {
      display: block;
    }
    /* 最终CTA */
    .cta-banner {
      background: var(--primary-red);
      border-radius: 20px;
      padding: 64px;
      text-align: center;
      color: white;
    }
    .cta-banner h2 {
      color: white;
      font-size: 40px;
      margin-bottom: 16px;
    }
    /* 页脚 */
    .footer {
      background: #1A202C;
      color: #A0AEC0;
      padding: 60px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
    }
    .footer-brand p {
      margin-top: 12px;
    }
    .footer-links h4 {
      color: white;
      margin-bottom: 16px;
    }
    .footer-links a {
      display: block;
      color: #A0AEC0;
      margin-bottom: 10px;
    }
    .footer-links a:hover {
      color: white;
    }
    .social-icons i {
      font-size: 20px;
      margin-right: 16px;
      color: #A0AEC0;
      transition: var(--transition);
    }
    .social-icons i:hover {
      color: var(--primary-red);
    }
    .copyright {
      border-top: 1px solid #2D3748;
      margin-top: 40px;
      padding-top: 24px;
      text-align: center;
      font-size: 14px;
    }
    /* 响应式 */
    @media (max-width: 1024px) {
      h1 { font-size: 40px; }
      .features-grid, .cases-grid { grid-template-columns: repeat(2,1fr); }
      .footer-grid { grid-template-columns: 1fr 1fr; }
    }
    @media (max-width: 768px) {
      .nav-menu { display: none; flex-direction: column; position: absolute; top: 70px; left: 0; width: 100%; background: #1A202C; padding: 20px; gap: 20px; }
      .nav-menu.active { display: flex; }
      .hamburger { display: block; }
      .hero-grid { flex-direction: column; }
      .scene-row, .scene-row.reverse { flex-direction: column; }
      .features-grid, .cases-grid { grid-template-columns: 1fr; }
      .cta-banner { padding: 40px 24px; }
    }