/* roulang page: index */
:root {
      --primary: #0B0E2D;
      --accent: #00F0FF;
      --bg: #FFFFFF;
      --bg-secondary: #F5F7FA;
      --emphasis: #FF3E6C;
      --text-primary: #1A1A2E;
      --text-secondary: #5A5A7A;
      --success: #00E676;
      --warning: #FFB300;
      --border-light: rgba(11, 14, 45, 0.06);
      --shadow-card: 0 4px 20px rgba(11, 14, 45, 0.06);
      --shadow-hover: 0 8px 30px rgba(11, 14, 45, 0.12);
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-xl: 20px;
      --font-sans: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", system-ui, -apple-system, sans-serif;
      --font-number: "Inter", "SF Pro Display", system-ui, sans-serif;
      --transition: all 0.25s ease;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    html {
      scroll-behavior: smooth;
    }
    body {
      font-family: var(--font-sans);
      background: var(--bg);
      color: var(--text-primary);
      line-height: 1.7;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: var(--transition);
    }
    button, .btn {
      cursor: pointer;
      font-family: inherit;
      transition: var(--transition);
    }
    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }
    /* 导航 */
    #nav {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 72px;
      background: rgba(255, 255, 255, 0.92);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
      border-bottom: 1px solid rgba(11, 14, 45, 0.06);
      z-index: 100;
      display: flex;
      align-items: center;
      transition: var(--transition);
    }
    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }
    .logo {
      display: flex;
      align-items: center;
      gap: 8px;
      font-weight: 700;
      font-size: 1.5rem;
      color: var(--primary);
      letter-spacing: 1px;
    }
    .logo-icon {
      width: 28px;
      height: 28px;
      background: radial-gradient(circle, #00F0FF 10%, #0B0E2D 80%);
      border-radius: 50%;
      box-shadow: 0 0 10px rgba(0,240,255,0.5);
      position: relative;
    }
    .logo-icon::after {
      content: "";
      position: absolute;
      top: 2px;
      left: 2px;
      width: 24px;
      height: 24px;
      border: 2px solid rgba(255,255,255,0.3);
      border-radius: 50%;
      transform: rotate(30deg);
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 28px;
    }
    .nav-links a {
      font-size: 15px;
      font-weight: 500;
      color: var(--text-secondary);
      position: relative;
      padding: 4px 0;
    }
    .nav-links a::after {
      content: "";
      position: absolute;
      bottom: -2px;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--accent);
      transition: width 0.2s ease;
    }
    .nav-links a:hover {
      color: var(--accent);
    }
    .nav-links a:hover::after {
      width: 100%;
    }
    .btn-nav {
      background: transparent;
      border: 2px solid var(--accent);
      color: var(--accent);
      padding: 8px 20px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 14px;
      margin-left: 12px;
    }
    .btn-nav:hover {
      background: var(--accent);
      color: var(--primary);
    }
    /* 移动端底部导航 */
    .mobile-bottom-nav {
      display: none;
      position: fixed;
      bottom: 0;
      left: 0;
      width: 100%;
      height: 56px;
      background: #fff;
      border-top: 1px solid rgba(11,14,45,0.08);
      z-index: 110;
      justify-content: space-around;
      align-items: center;
      padding: 0 8px;
    }
    .mobile-tab {
      display: flex;
      flex-direction: column;
      align-items: center;
      gap: 4px;
      font-size: 11px;
      color: var(--text-secondary);
      font-weight: 500;
      transition: var(--transition);
    }
    .mobile-tab i {
      font-size: 20px;
      color: inherit;
    }
    .mobile-tab.active {
      color: var(--accent);
    }
    /* Hero */
    #hero {
      padding: 140px 0 100px;
      background: linear-gradient(135deg, #0B0E2D 0%, #1A1A3E 100%);
      position: relative;
      overflow: hidden;
      color: white;
    }
    .hero-content {
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 40px;
      flex-wrap: wrap;
      position: relative;
      z-index: 2;
    }
    .hero-text {
      flex: 1 1 500px;
    }
    .hero-text h1 {
      font-size: 52px;
      font-weight: 700;
      line-height: 1.2;
      margin-bottom: 20px;
      color: white;
    }
    .hero-text p {
      font-size: 18px;
      color: rgba(255,255,255,0.7);
      margin-bottom: 32px;
      max-width: 500px;
    }
    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .btn-primary {
      background: var(--accent);
      color: var(--primary);
      font-weight: 600;
      padding: 12px 32px;
      border-radius: var(--radius-btn);
      border: none;
      font-size: 16px;
      box-shadow: 0 4px 14px rgba(0,240,255,0.3);
    }
    .btn-primary:hover {
      background: #00d4e0;
      box-shadow: 0 0 20px rgba(0,240,255,0.6);
    }
    .btn-outline {
      background: transparent;
      border: 2px solid rgba(255,255,255,0.5);
      color: white;
      padding: 12px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 16px;
    }
    .btn-outline:hover {
      background: rgba(255,255,255,0.1);
      border-color: var(--accent);
    }
    .hero-image {
      flex: 1 1 400px;
      border-radius: var(--radius-xl);
      overflow: hidden;
      box-shadow: 0 0 40px rgba(0,240,255,0.2);
      border: 1px solid rgba(255,255,255,0.15);
    }
    .hero-image img {
      width: 100%;
      object-fit: cover;
      aspect-ratio: 4/3;
    }
    .particles {
      position: absolute;
      top:0;left:0;width:100%;height:100%;
      pointer-events: none;
      background: radial-gradient(circle at 20% 30%, rgba(0,240,255,0.08) 0%, transparent 40%);
    }
    /* 板块通用 */
    section {
      padding: 90px 0;
    }
    .section-title {
      text-align: center;
      margin-bottom: 60px;
    }
    .section-title h2 {
      font-size: 38px;
      font-weight: 600;
      color: var(--primary);
    }
    .section-title p {
      color: var(--text-secondary);
      margin-top: 12px;
      font-size: 18px;
    }
    .grid-3 {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .card {
      background: white;
      border-radius: var(--radius-card);
      padding: 32px 24px;
      box-shadow: var(--shadow-card);
      border: 1px solid var(--border-light);
      transition: var(--transition);
    }
    .card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
    }
    /* 价值主张 */
    .value-icon {
      width: 48px;
      height: 48px;
      color: var(--accent);
      font-size: 40px;
      margin-bottom: 20px;
    }
    .card h3 {
      font-size: 24px;
      margin-bottom: 12px;
      font-weight: 600;
    }
    /* 功能图文 */
    .feature-row {
      display: flex;
      align-items: center;
      gap: 60px;
      margin-bottom: 80px;
    }
    .feature-row.reverse {
      flex-direction: row-reverse;
    }
    .feature-text {
      flex:1;
    }
    .feature-text h2 {
      font-size: 32px;
      margin-bottom: 16px;
    }
    .feature-list {
      list-style: none;
      margin-top: 20px;
    }
    .feature-list li {
      display: flex;
      align-items: center;
      gap: 12px;
      margin-bottom: 12px;
      color: var(--text-secondary);
    }
    .feature-list i {
      color: var(--success);
      font-size: 18px;
    }
    .feature-image {
      flex:1;
      border-radius: var(--radius-xl);
      overflow: hidden;
      box-shadow: 0 10px 25px rgba(0,0,0,0.2);
    }
    /* 场景 */
    .scenario-card {
      background: var(--bg-secondary);
      border-radius: var(--radius-card);
      padding: 32px 24px;
      text-align: center;
      transition: var(--transition);
      border: 1px solid transparent;
    }
    .scenario-card:hover {
      background: white;
      box-shadow: var(--shadow-hover);
      border-color: var(--border-light);
    }
    /* 案例 */
    .cases-grid {
      display: grid;
      grid-template-columns: repeat(2,1fr);
      gap: 24px;
    }
    .case-card {
      background: white;
      border-radius: var(--radius-card);
      padding: 24px;
      border-left: 5px solid var(--accent);
      box-shadow: var(--shadow-card);
    }
    .stats-row {
      display: flex;
      justify-content: space-around;
      margin: 40px 0;
      flex-wrap: wrap;
    }
    .stat-item {
      text-align: center;
    }
    .stat-number {
      font-family: var(--font-number);
      font-size: 48px;
      font-weight: 700;
      color: var(--emphasis);
    }
    /* 价格 */
    .pricing-card {
      background: white;
      border-radius: var(--radius-card);
      padding: 32px;
      box-shadow: var(--shadow-card);
      text-align: center;
      position: relative;
    }
    .pricing-card.featured {
      background: var(--primary);
      color: white;
      transform: scale(1.03);
      border: 1px solid var(--accent);
    }
    .badge {
      background: var(--emphasis);
      color: white;
      padding: 4px 16px;
      border-radius: 20px;
      font-size: 13px;
      font-weight: 600;
      display: inline-block;
      margin-bottom: 12px;
    }
    .price {
      font-family: var(--font-number);
      font-size: 42px;
      font-weight: 700;
      margin: 16px 0;
    }
    /* FAQ */
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
    }
    .faq-item {
      border-bottom: 1px solid rgba(0,0,0,0.06);
      padding: 20px 0;
    }
    .faq-question {
      font-weight: 600;
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
      font-size: 18px;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      color: var(--text-secondary);
      margin-top: 8px;
    }
    .faq-item.open .faq-answer {
      max-height: 200px;
    }
    /* CTA */
    #cta {
      background: var(--primary);
      color: white;
      text-align: center;
    }
    /* 页脚 */
    footer {
      background: var(--bg-secondary);
      padding: 60px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
    }
    @media (max-width: 1024px) {
      .grid-3 { grid-template-columns: repeat(2,1fr); }
      .cases-grid { grid-template-columns: 1fr; }
    }
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .mobile-bottom-nav { display: flex; }
      #nav { height: 64px; }
      .hero-text h1 { font-size: 36px; }
      .grid-3, .cases-grid { grid-template-columns: 1fr; }
      .feature-row { flex-direction: column; }
      .footer-grid { grid-template-columns: 1fr; }
      .btn-nav { display: none; }
      section { padding: 60px 0; }
    }