/* roulang page: index */
:root {
      --primary-deep: #0A1929;
      --accent-cyan: #00E5FF;
      --highlight-orange: #FF5722;
      --bg-page: #0D1B2A;
      --card-glass: rgba(255, 255, 255, 0.03);
      --text-main: #E0E6ED;
      --text-muted: #8899AA;
      --text-white: #FFFFFF;
      --border-glow: rgba(0, 229, 255, 0.15);
      --border-hover: rgba(0, 229, 255, 0.4);
      --shadow-card: 0 8px 32px rgba(0, 0, 0, 0.4);
      --shadow-hover: 0 12px 40px rgba(0, 229, 255, 0.15);
      --radius-card: 16px;
      --radius-btn: 12px;
      --radius-input: 8px;
      --font-sans: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
      --transition-smooth: all 0.3s ease;
    }

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

    body {
      font-family: var(--font-sans);
      background-color: var(--bg-page);
      color: var(--text-main);
      line-height: 1.7;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }

    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 24px;
      width: 100%;
    }

    h1, h2, h3 {
      font-weight: 600;
      color: var(--text-white);
    }

    h1 {
      font-size: 48px;
      line-height: 1.2;
      font-weight: 700;
      letter-spacing: -0.5px;
    }

    h2 {
      font-size: 36px;
      line-height: 1.3;
      margin-bottom: 24px;
      padding-left: 16px;
      border-left: 4px solid var(--accent-cyan);
      display: flex;
      align-items: center;
    }

    h3 {
      font-size: 22px;
      line-height: 1.4;
      color: var(--text-main);
      margin-bottom: 8px;
    }

    p, .text-body {
      color: var(--text-muted);
      font-size: 16px;
      line-height: 1.7;
    }

    .text-label {
      font-size: 13px;
      text-transform: uppercase;
      letter-spacing: 1px;
      color: var(--accent-cyan);
      font-weight: 500;
    }

    a {
      color: var(--accent-cyan);
      text-decoration: none;
      transition: var(--transition-smooth);
    }
    a:hover {
      color: var(--text-white);
    }

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

    /* 按钮系统 */
    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 16px;
      transition: var(--transition-smooth);
      cursor: pointer;
      border: none;
      background: transparent;
      text-align: center;
      white-space: nowrap;
    }

    .btn-primary {
      background: var(--highlight-orange);
      color: white;
      box-shadow: 0 0 20px rgba(255, 87, 34, 0.5);
    }
    .btn-primary:hover {
      transform: translateY(-2px);
      box-shadow: 0 0 28px rgba(255, 87, 34, 0.7);
      color: white;
    }

    .btn-secondary {
      border: 1px solid var(--accent-cyan);
      color: var(--accent-cyan);
      background: transparent;
    }
    .btn-secondary:hover {
      background: rgba(0, 229, 255, 0.1);
      box-shadow: 0 0 15px rgba(0, 229, 255, 0.4);
      transform: translateY(-2px);
      color: var(--accent-cyan);
    }

    .btn-lg {
      padding: 16px 48px;
      font-size: 18px;
      border-radius: var(--radius-btn);
    }

    /* 玻璃拟态卡片 */
    .glass-card {
      background: var(--card-glass);
      backdrop-filter: blur(20px) saturate(180%);
      border: 1px solid var(--border-glow);
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-card);
      transition: var(--transition-smooth);
    }
    .glass-card:hover {
      box-shadow: var(--shadow-hover);
      border-color: var(--border-hover);
      transform: translateY(-4px);
    }

    /* 导航 */
    #nav {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      background: rgba(10, 25, 41, 0.85);
      backdrop-filter: blur(10px);
      border-bottom: 1px solid rgba(0, 229, 255, 0.1);
      z-index: 100;
      padding: 12px 0;
    }
    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
    }
    .logo {
      font-size: 24px;
      font-weight: 700;
      color: var(--text-white);
      letter-spacing: 1px;
    }
    .logo span {
      color: var(--accent-cyan);
    }
    .nav-links {
      display: flex;
      gap: 32px;
      align-items: center;
    }
    .nav-links a {
      color: var(--text-muted);
      font-weight: 500;
      font-size: 15px;
      transition: var(--transition-smooth);
      position: relative;
    }
    .nav-links a:hover,
    .nav-links a.active {
      color: var(--accent-cyan);
    }
    .nav-links a.active::after {
      content: '';
      position: absolute;
      bottom: -4px;
      left: 0;
      width: 100%;
      height: 2px;
      background: var(--accent-cyan);
    }
    .menu-toggle {
      display: none;
      background: none;
      border: none;
      color: var(--accent-cyan);
      font-size: 28px;
      cursor: pointer;
    }
    /* 移动端导航 */
    @media (max-width: 768px) {
      .nav-links {
        position: fixed;
        top: 0;
        right: -100%;
        width: 80%;
        height: 100vh;
        background: #0A1929;
        flex-direction: column;
        justify-content: center;
        align-items: center;
        gap: 40px;
        transition: right 0.3s ease;
        backdrop-filter: blur(15px);
        background: rgba(10, 25, 41, 0.98);
      }
      .nav-links.open {
        right: 0;
      }
      .menu-toggle {
        display: block;
        z-index: 110;
      }
      .nav-container {
        flex-wrap: wrap;
      }
    }

    /* Hero */
    #hero {
      min-height: 90vh;
      display: flex;
      align-items: center;
      background: linear-gradient(135deg, #0A1929 0%, #0D1B2A 100%);
      position: relative;
      overflow: hidden;
    }
    .hero-bg {
      position: absolute;
      top:0;left:0;width:100%;height:100%;
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      opacity: 0.3;
      background-blend-mode: overlay;
    }
    .hero-content {
      position: relative;
      z-index: 2;
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 40px;
      width: 100%;
    }
    .hero-text {
      flex: 1;
    }
    .hero-text h1 {
      margin-bottom: 24px;
    }
    .hero-text .highlight {
      color: var(--accent-cyan);
    }
    .hero-text p {
      font-size: 18px;
      margin-bottom: 32px;
      max-width: 500px;
    }
    .hero-actions {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .hero-visual {
      flex: 1;
      display: flex;
      justify-content: center;
    }
    .hero-visual img {
      max-width: 100%;
      border-radius: var(--radius-card);
      box-shadow: 0 20px 40px rgba(0,0,0,0.6);
    }

    section {
      padding: 100px 0;
    }

    /* 三列网格 */
    .grid-3 {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .advantage-card {
      text-align: center;
      padding: 32px 24px;
    }
    .icon-placeholder {
      width: 64px;
      height: 64px;
      margin: 0 auto 20px;
      background: rgba(0,229,255,0.1);
      border-radius: 20px;
      display: flex;
      align-items: center;
      justify-content: center;
      color: var(--accent-cyan);
      font-size: 30px;
    }

    /* 左右交替 */
    .feature-row {
      display: flex;
      align-items: center;
      gap: 60px;
      margin-bottom: 80px;
    }
    .feature-row.reverse {
      flex-direction: row-reverse;
    }
    .feature-img {
      flex: 1;
      border-radius: var(--radius-card);
      overflow: hidden;
      box-shadow: 0 15px 30px rgba(0,0,0,0.5);
    }
    .feature-text {
      flex: 1;
    }
    .tech-tag {
      display: inline-block;
      background: rgba(0,229,255,0.1);
      color: var(--accent-cyan);
      padding: 6px 14px;
      border-radius: 20px;
      font-size: 13px;
      margin-right: 8px;
      margin-top: 12px;
    }

    .scenario-card {
      overflow: hidden;
      padding: 0;
    }
    .scenario-card img {
      width: 100%;
      height: 200px;
      object-fit: cover;
    }
    .scenario-card .card-body {
      padding: 24px;
    }

    .case-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .case-card {
      display: flex;
      align-items: center;
      gap: 16px;
      background: rgba(255,255,255,0.02);
      padding: 20px;
      border-radius: 12px;
      border: 1px solid var(--border-glow);
    }
    .case-logo {
      width: 48px;
      height: 48px;
      background: #0A1929;
      border-radius: 12px;
      display: flex;
      align-items: center;
      justify-content: center;
      color: var(--accent-cyan);
    }
    .case-data {
      color: var(--highlight-orange);
      font-weight: 700;
    }

    /* FAQ */
    .faq-item {
      background: rgba(255,255,255,0.02);
      border: 1px solid rgba(0,229,255,0.08);
      border-radius: 12px;
      margin-bottom: 12px;
      overflow: hidden;
      transition: var(--transition-smooth);
    }
    .faq-question {
      padding: 20px 24px;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-weight: 600;
      color: var(--text-white);
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      padding: 0 24px;
      color: var(--text-muted);
    }
    .faq-item.active {
      border-color: rgba(0,229,255,0.3);
      background: rgba(0,229,255,0.03);
    }
    .faq-item.active .faq-answer {
      max-height: 500px;
      padding-bottom: 20px;
    }
    .faq-icon {
      color: var(--accent-cyan);
      font-size: 20px;
    }

    #cta {
      background: #0A1929;
      text-align: center;
    }

    footer {
      background: #060F1A;
      padding: 60px 0 30px;
      color: var(--text-muted);
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 30px;
      margin-bottom: 40px;
    }
    .social-icons i {
      font-size: 18px;
      width: 40px;
      height: 40px;
      border: 1px solid rgba(0,229,255,0.2);
      border-radius: 50%;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      margin-right: 12px;
      transition: var(--transition-smooth);
    }
    .social-icons i:hover {
      background: var(--accent-cyan);
      color: #0A1929;
    }

    @media (max-width: 1024px) {
      .grid-3, .case-grid { grid-template-columns: repeat(2,1fr); }
      .feature-row { flex-direction: column; gap: 30px; }
      .feature-row.reverse { flex-direction: column; }
      .hero-content { flex-direction: column; text-align: center; }
      .hero-text p { margin: 0 auto 24px; }
    }
    @media (max-width: 768px) {
      h1 { font-size: 32px; }
      h2 { font-size: 26px; }
      h3 { font-size: 18px; }
      .grid-3, .case-grid, .footer-grid { grid-template-columns: 1fr; }
      section { padding: 60px 0; }
      .btn-lg { width: 100%; }
      .hero-actions { justify-content: center; }
      .nav-links .btn { display: none; }
    }