/* roulang page: index */
/* 设计变量与基础重置 */
    :root {
      --primary: #00E5FF;
      --primary-glow: rgba(0, 229, 255, 0.7);
      --secondary-bg: #0A0F1F;
      --deep-bg: #020616;
      --accent: #7B2FFF;
      --accent-glow: rgba(123, 47, 255, 0.5);
      --text-white: #FFFFFF;
      --text-gray: #B0C4DE;
      --card-bg: rgba(255, 255, 255, 0.03);
      --card-border: rgba(0, 229, 255, 0.15);
      --card-shadow: 0 8px 32px rgba(0, 229, 255, 0.08);
      --radius-card: 16px;
      --radius-btn: 30px;
      --radius-input: 10px;
      --font-sans: 'Inter', 'PingFang SC', 'Microsoft YaHei', 'SF Pro Display', system-ui, -apple-system, sans-serif;
      --transition: 0.3s ease;
      --container-max: 1280px;
      --section-gap: 80px;
    }

    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }

    body {
      background: radial-gradient(circle at 30% 10%, #0A1A2F, #020616 80%);
      font-family: var(--font-sans);
      color: var(--text-gray);
      line-height: 1.8;
      -webkit-font-smoothing: antialiased;
      overflow-x: hidden;
    }

    .container {
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 24px;
    }

    a {
      text-decoration: none;
      color: inherit;
      transition: var(--transition);
    }

    img {
      max-width: 100%;
      display: block;
    }

    button, input {
      font-family: inherit;
      border: none;
      outline: none;
      background: transparent;
    }

    /* 玻璃拟态卡片基础 */
    .glass-card {
      background: var(--card-bg);
      backdrop-filter: blur(18px);
      -webkit-backdrop-filter: blur(18px);
      border: 1px solid var(--card-border);
      border-radius: var(--radius-card);
      box-shadow: var(--card-shadow);
    }

    /* 导航栏 */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      background: transparent;
      transition: background 0.4s ease, backdrop-filter 0.4s ease;
    }

    .site-header.scrolled {
      background: rgba(10, 15, 31, 0.85);
      backdrop-filter: blur(20px);
      -webkit-backdrop-filter: blur(20px);
      border-bottom: 1px solid rgba(0, 229, 255, 0.15);
    }

    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      padding: 16px 24px;
      max-width: var(--container-max);
      margin: 0 auto;
    }

    .logo {
      font-size: 1.8rem;
      font-weight: 700;
      letter-spacing: -0.5px;
      color: var(--text-white);
      display: flex;
      align-items: center;
      gap: 6px;
    }
    .logo span {
      color: var(--primary);
      text-shadow: 0 0 12px var(--primary-glow);
    }

    .nav-links {
      display: flex;
      align-items: center;
      gap: 2rem;
    }

    .nav-links a {
      color: var(--text-gray);
      font-weight: 500;
      position: relative;
      padding: 4px 0;
    }

    .nav-links a:hover,
    .nav-links a.active {
      color: var(--primary);
      text-shadow: 0 0 8px var(--primary-glow);
    }

    .btn-primary {
      background: rgba(0, 229, 255, 0.1);
      border: 1px solid var(--primary);
      color: var(--primary);
      padding: 10px 28px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      box-shadow: 0 0 15px rgba(0, 229, 255, 0.3);
      transition: var(--transition);
      cursor: pointer;
      display: inline-block;
      text-align: center;
    }

    .btn-primary:hover {
      background: var(--primary);
      color: #020616;
      box-shadow: 0 0 30px var(--primary-glow);
      transform: translateY(-2px);
    }

    .menu-toggle {
      display: none;
      flex-direction: column;
      gap: 5px;
      background: transparent;
      border: none;
      cursor: pointer;
    }
    .menu-toggle span {
      width: 25px;
      height: 2px;
      background: var(--text-white);
      transition: 0.3s;
    }

    /* 移动端导航抽屉 */
    .mobile-nav {
      position: fixed;
      top: 0;
      right: 0;
      width: 75%;
      max-width: 320px;
      height: 100vh;
      background: rgba(10, 15, 31, 0.96);
      backdrop-filter: blur(30px);
      display: flex;
      flex-direction: column;
      padding: 2rem;
      transform: translateX(100%);
      transition: transform 0.4s ease;
      z-index: 999;
      border-left: 1px solid var(--card-border);
    }
    .mobile-nav.open {
      transform: translateX(0);
    }
    .mobile-nav a {
      padding: 1rem 0;
      font-size: 1.2rem;
      border-bottom: 1px solid rgba(0,229,255,0.1);
      color: var(--text-white);
    }

    /* 区块标题 */
    .section-title {
      font-size: 2.4rem;
      font-weight: 700;
      color: var(--text-white);
      margin-bottom: 0.75rem;
      letter-spacing: -0.5px;
    }
    .section-subtitle {
      color: var(--text-gray);
      margin-bottom: 2.5rem;
      font-size: 1.1rem;
    }

    /* Hero */
    .hero {
      display: flex;
      align-items: center;
      justify-content: space-between;
      min-height: 100vh;
      padding-top: 80px;
      gap: 2rem;
    }
    .hero-content {
      flex: 1;
    }
    .hero h1 {
      font-size: 3.5rem;
      font-weight: 700;
      color: var(--text-white);
      line-height: 1.3;
      margin-bottom: 1.2rem;
    }
    .hero-highlight {
      color: var(--primary);
      text-shadow: 0 0 25px var(--primary-glow);
    }
    .hero-desc {
      font-size: 1.15rem;
      margin-bottom: 2rem;
      max-width: 500px;
    }
    .hero-buttons {
      display: flex;
      gap: 1rem;
      flex-wrap: wrap;
    }
    .btn-secondary {
      border: 1px solid rgba(255,255,255,0.25);
      color: var(--text-white);
      padding: 10px 28px;
      border-radius: var(--radius-btn);
      font-weight: 500;
      transition: var(--transition);
    }
    .btn-secondary:hover {
      border-color: var(--primary);
      color: var(--primary);
      box-shadow: 0 0 18px rgba(0,229,255,0.3);
    }
    .hero-visual {
      flex: 1;
      position: relative;
      min-height: 320px;
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      border-radius: 32px;
      overflow: hidden;
      box-shadow: 0 20px 40px rgba(0,0,0,0.6);
      border: 1px solid rgba(0,229,255,0.2);
    }
    .hero-visual::after {
      content: '';
      position: absolute;
      inset: 0;
      background: linear-gradient(135deg, rgba(0,229,255,0.15), rgba(123,47,255,0.2));
    }

    /* 指标看板 */
    .dashboard-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
      margin-top: 2rem;
    }
    .stat-card {
      text-align: center;
      padding: 2rem 1rem;
    }
    .stat-number {
      font-size: 2.8rem;
      font-weight: 800;
      color: var(--primary);
      text-shadow: 0 0 20px var(--primary-glow);
      font-feature-settings: "tnum";
      letter-spacing: 0.5px;
    }
    .stat-label {
      color: var(--text-gray);
      margin-top: 0.5rem;
    }

    /* 服务卡片网格 */
    .services-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .service-card {
      padding: 2rem;
      transition: all 0.3s ease;
      display: flex;
      flex-direction: column;
    }
    .service-card:hover {
      border-color: var(--primary);
      box-shadow: 0 12px 28px rgba(0,229,255,0.2);
      transform: translateY(-6px);
    }
    .service-icon {
      font-size: 2.2rem;
      margin-bottom: 1rem;
      color: var(--primary);
    }
    .service-card h3 {
      color: var(--primary);
      margin-bottom: 0.75rem;
    }
    .text-link {
      color: var(--primary);
      margin-top: 1rem;
      font-weight: 500;
      display: inline-block;
    }

    /* 对比区域 */
    .comparison-row {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 2rem;
    }
    .compare-card {
      padding: 2rem;
      background: rgba(255,255,255,0.02);
      backdrop-filter: blur(12px);
      border-radius: 24px;
      border: 1px solid rgba(255,255,255,0.08);
    }
    .compare-card.highlight {
      border-color: var(--accent);
      box-shadow: 0 0 24px rgba(123,47,255,0.25);
      background: rgba(123,47,255,0.05);
    }
    .compare-item {
      display: flex;
      align-items: center;
      gap: 10px;
      margin: 1rem 0;
    }

    /* 案例卡片 */
    .cases-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .case-card {
      padding: 2rem;
      background: rgba(0,0,0,0.25);
      border-left: 4px solid var(--primary);
    }
    .case-quote {
      font-style: italic;
      margin: 1rem 0;
      color: #ddd;
    }

    /* FAQ */
    .faq-item {
      border-bottom: 1px solid rgba(0,229,255,0.2);
      padding: 1.2rem 0;
      cursor: pointer;
    }
    .faq-question {
      display: flex;
      justify-content: space-between;
      font-weight: 600;
      color: white;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: 0.4s;
      color: var(--text-gray);
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding-top: 0.8rem;
    }

    /* CTA表单 */
    .cta-box {
      background: radial-gradient(circle at center, rgba(0,229,255,0.08), transparent 70%);
      padding: 3rem;
      border-radius: 32px;
      text-align: center;
    }
    .input-group {
      display: flex;
      max-width: 480px;
      margin: 2rem auto 0;
    }
    .input-group input {
      flex:1;
      background: rgba(255,255,255,0.05);
      border: 1px solid var(--card-border);
      border-radius: var(--radius-input) 0 0 var(--radius-input);
      padding: 14px 20px;
      color: white;
      backdrop-filter: blur(8px);
    }
    .input-group button {
      border-radius: 0 var(--radius-input) var(--radius-input) 0;
      background: var(--primary);
      color: #020616;
      font-weight: bold;
      padding: 0 28px;
      cursor: pointer;
    }

    /* 页脚 */
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 2rem;
      padding: 3rem 0;
    }
    .copyright {
      text-align: center;
      border-top: 1px solid rgba(255,255,255,0.08);
      padding: 1.5rem 0;
      font-size: 0.9rem;
    }

    @media (max-width: 1024px) {
      .hero {
        flex-direction: column;
        text-align: center;
      }
      .dashboard-grid { grid-template-columns: repeat(2,1fr); }
      .services-grid { grid-template-columns: 1fr 1fr; }
      .cases-grid { grid-template-columns: 1fr; }
    }
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .menu-toggle { display: flex; }
      .hero h1 { font-size: 2.4rem; }
      .comparison-row { grid-template-columns: 1fr; }
      .footer-grid { grid-template-columns: 1fr; }
      .section-title { font-size: 2rem; }
      .dashboard-grid { grid-template-columns: 1fr; }
      .services-grid { grid-template-columns: 1fr; }
    }