/* roulang page: index */
:root {
      --deep-space: #0A0E27;
      --midnight-blue: #1A1F3A;
      --electric-blue: #00C2FF;
      --energy-orange: #FF6B35;
      --titanium-gray: #B0B8C8;
      --subtle-gray: #7A8395;
      --glass-bg: rgba(255, 255, 255, 0.05);
      --glass-border: rgba(255, 255, 255, 0.15);
      --glass-bg-hover: rgba(255, 255, 255, 0.1);
      --card-radius: 16px;
      --btn-radius: 8px;
      --shadow-card: 0 8px 32px rgba(0, 0, 0, 0.4);
      --glow-blue: 0 0 20px rgba(0, 194, 255, 0.6);
      --glow-orange: 0 0 15px rgba(255, 107, 53, 0.7);
      --container-max: 1200px;
      --section-gap: 120px;
      --card-gap: 24px;
      --text-body: #B0B8C8;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    html {
      scroll-behavior: smooth;
      font-size: 16px;
    }
    body {
      font-family: 'Inter', 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', sans-serif;
      background: radial-gradient(circle at 20% 10%, #1A1F3A 0%, #0A0E27 90%);
      color: #E6EDF5;
      line-height: 1.5;
      min-height: 100vh;
      -webkit-font-smoothing: antialiased;
      -moz-osx-font-smoothing: grayscale;
      background-attachment: fixed;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: color 0.2s ease;
    }
    button, input, textarea {
      font-family: inherit;
      outline: none;
    }
    .container {
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 20px;
    }
    /* 导航 */
    .header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 72px;
      background: rgba(10, 14, 39, 0.85);
      backdrop-filter: blur(20px);
      -webkit-backdrop-filter: blur(20px);
      border-bottom: 1px solid rgba(255, 255, 255, 0.08);
      z-index: 100;
      display: flex;
      align-items: center;
    }
    .nav-container {
      display: flex;
      justify-content: space-between;
      align-items: center;
      width: 100%;
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 20px;
    }
    .logo {
      font-weight: 700;
      font-size: 1.7rem;
      letter-spacing: -0.5px;
      color: white;
      display: flex;
      align-items: center;
      gap: 8px;
    }
    .logo span {
      background: linear-gradient(135deg, #00C2FF 0%, #6EE7FF 100%);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
    }
    .nav-menu {
      display: flex;
      align-items: center;
      gap: 32px;
    }
    .nav-link {
      font-size: 0.95rem;
      color: #B0B8C8;
      font-weight: 500;
      position: relative;
      padding: 8px 0;
      transition: color 0.2s;
    }
    .nav-link:hover, .nav-link.active {
      color: white;
    }
    .nav-link::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0%;
      height: 2px;
      background: var(--electric-blue);
      box-shadow: 0 0 12px var(--electric-blue);
      transition: width 0.25s ease;
    }
    .nav-link:hover::after, .nav-link.active::after {
      width: 100%;
    }
    .cta-btn {
      background: var(--electric-blue);
      color: #0A0E27;
      border: none;
      padding: 10px 24px;
      border-radius: var(--btn-radius);
      font-weight: 600;
      font-size: 0.9rem;
      cursor: pointer;
      box-shadow: var(--glow-blue);
      transition: all 0.25s ease;
      letter-spacing: 0.3px;
      white-space: nowrap;
    }
    .cta-btn:hover {
      box-shadow: 0 0 30px rgba(0, 194, 255, 0.9);
      transform: scale(1.05);
      background: #33d0ff;
    }
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      background: transparent;
      border: none;
      cursor: pointer;
      padding: 8px;
    }
    .hamburger span {
      width: 25px;
      height: 2px;
      background: white;
      border-radius: 2px;
      transition: 0.2s;
    }
    @media (max-width: 1024px) {
      .nav-menu {
        gap: 24px;
      }
    }
    @media (max-width: 768px) {
      .nav-menu {
        position: fixed;
        top: 72px;
        left: 0;
        width: 100%;
        background: rgba(10, 14, 39, 0.95);
        backdrop-filter: blur(24px);
        flex-direction: column;
        padding: 32px 20px;
        gap: 24px;
        display: none;
        border-bottom: 1px solid rgba(255,255,255,0.1);
      }
      .nav-menu.active {
        display: flex;
      }
      .hamburger {
        display: flex;
      }
      .cta-btn.desktop-cta {
        display: none;
      }
    }
    .mobile-cta {
      display: none;
    }
    @media (max-width: 768px) {
      .mobile-cta {
        display: block;
        width: 100%;
      }
    }
    /* Hero */
    .hero {
      min-height: 100vh;
      display: flex;
      align-items: center;
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      position: relative;
      margin-top: 0;
    }
    .hero-overlay {
      position: absolute;
      inset: 0;
      background: linear-gradient(90deg, rgba(10,14,39,0.85) 0%, rgba(10,14,39,0.6) 100%);
      z-index: 1;
    }
    .hero-content {
      position: relative;
      z-index: 2;
      max-width: 700px;
      padding: 0 20px;
    }
    .hero h1 {
      font-size: clamp(2.2rem, 5vw, 3.2rem);
      font-weight: 700;
      line-height: 1.2;
      margin-bottom: 24px;
      color: white;
    }
    .hero .subtitle {
      font-size: 1.2rem;
      color: #B0B8C8;
      margin-bottom: 40px;
      max-width: 550px;
    }
    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .btn-primary {
      background: var(--electric-blue);
      color: #0A0E27;
      padding: 14px 32px;
      border-radius: var(--btn-radius);
      font-weight: 700;
      box-shadow: var(--glow-blue);
      border: none;
      cursor: pointer;
      transition: 0.25s;
      display: inline-block;
    }
    .btn-primary:hover {
      box-shadow: 0 0 35px rgba(0,194,255,0.9);
      transform: translateY(-2px);
    }
    .btn-secondary {
      background: transparent;
      border: 2px solid var(--electric-blue);
      color: var(--electric-blue);
      padding: 14px 32px;
      border-radius: var(--btn-radius);
      font-weight: 600;
      transition: 0.25s;
      cursor: pointer;
    }
    .btn-secondary:hover {
      background: rgba(0,194,255,0.1);
      border-color: #33d0ff;
    }
    /* 通用板块 */
    section {
      padding: var(--section-gap) 0;
    }
    @media (max-width: 768px) {
      section {
        padding: 80px 0;
      }
    }
    .section-title {
      font-size: 2.2rem;
      font-weight: 700;
      margin-bottom: 16px;
      color: white;
    }
    .section-desc {
      color: #B0B8C8;
      max-width: 700px;
      margin-bottom: 48px;
    }
    /* 玻璃卡片 */
    .glass-card {
      background: var(--glass-bg);
      border: 1px solid var(--glass-border);
      backdrop-filter: blur(16px);
      -webkit-backdrop-filter: blur(16px);
      border-radius: var(--card-radius);
      padding: 32px;
      box-shadow: var(--shadow-card);
      transition: all 0.3s ease;
    }
    .glass-card:hover {
      background: var(--glass-bg-hover);
      border-color: rgba(0,194,255,0.5);
      box-shadow: 0 0 25px rgba(0,194,255,0.4);
      transform: translateY(-6px);
    }
    .features-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
      gap: var(--card-gap);
    }
    .icon-placeholder {
      width: 48px;
      height: 48px;
      background: rgba(0,194,255,0.15);
      border-radius: 12px;
      margin-bottom: 20px;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 24px;
    }
    /* 解决方案左右交替 */
    .solution-row {
      display: flex;
      flex-wrap: wrap;
      align-items: center;
      gap: 48px;
      margin-bottom: 80px;
    }
    .solution-text, .solution-img {
      flex: 1 1 300px;
    }
    .solution-img img {
      border-radius: 20px;
      box-shadow: 0 10px 30px rgba(0,0,0,0.5);
    }
    /* 数据卡片 */
    .stats-grid {
      display: flex;
      flex-wrap: wrap;
      gap: 24px;
      justify-content: center;
    }
    .stat-card {
      background: rgba(255,255,255,0.03);
      border: 1px solid rgba(255,255,255,0.1);
      border-radius: 20px;
      padding: 32px 24px;
      text-align: center;
      min-width: 180px;
      backdrop-filter: blur(8px);
    }
    .stat-number {
      font-size: 2.8rem;
      font-weight: 700;
      color: var(--energy-orange);
      text-shadow: 0 0 18px rgba(255,107,53,0.7);
    }
    /* 证言 */
    .testimonial-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
      gap: 24px;
    }
    /* FAQ */
    .faq-item {
      border: 1px solid rgba(255,255,255,0.08);
      border-radius: 12px;
      margin-bottom: 16px;
      background: rgba(255,255,255,0.02);
      overflow: hidden;
    }
    .faq-question {
      background: rgba(255,255,255,0.04);
      padding: 20px;
      font-weight: 600;
      display: flex;
      justify-content: space-between;
      cursor: pointer;
    }
    .faq-answer {
      padding: 20px;
      background: rgba(255,255,255,0.06);
      color: #B0B8C8;
      display: none;
    }
    .faq-item.active .faq-answer {
      display: block;
    }
    /* CTA */
    .cta-section {
      background: linear-gradient(145deg, #0A0E27, #141a36);
      border-radius: 28px;
      padding: 60px 32px;
      text-align: center;
      border: 1px solid rgba(0,194,255,0.3);
    }
    .footer {
      background: #080B1A;
      padding: 60px 0 30px;
      color: #7A8395;
    }
    .footer-grid {
      display: flex;
      flex-wrap: wrap;
      gap: 40px;
      justify-content: space-between;
    }
    @media (max-width: 768px) {
      .footer-grid {
        flex-direction: column;
      }
    }