/* roulang page: index */
:root {
      --primary: #00F0FF;
      --primary-glow: rgba(0,240,255,0.5);
      --accent: #FF3CAC;
      --accent-glow: rgba(255,60,172,0.45);
      --bg-deep: #0A0E27;
      --bg-darker: #060918;
      --glass-bg: rgba(255,255,255,0.04);
      --glass-border: rgba(0,240,255,0.12);
      --text-primary: #FFFFFF;
      --text-secondary: rgba(255,255,255,0.75);
      --text-muted: rgba(255,255,255,0.45);
      --radius-card: 16px;
      --radius-btn: 8px;
      --font-sans: "PingFang SC", "Microsoft YaHei", "Noto Sans SC", sans-serif;
      --font-english: "Inter", "Rajdhani", sans-serif;
      --transition: 0.25s ease-out;
    }

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

    body {
      font-family: var(--font-sans);
      background-color: var(--bg-deep);
      color: var(--text-secondary);
      line-height: 1.5;
      -webkit-font-smoothing: antialiased;
      overflow-x: hidden;
    }

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

    h1, h2, h3, h4 {
      color: var(--text-primary);
      font-weight: 700;
    }

    h1 {
      font-size: 44px;
      line-height: 1.2;
      letter-spacing: -0.5px;
    }

    h2 {
      font-size: 32px;
      line-height: 1.25;
    }

    h3 {
      font-size: 22px;
      line-height: 1.3;
      font-weight: 600;
    }

    h4 {
      font-size: 18px;
      line-height: 1.4;
      font-weight: 600;
    }

    p {
      font-size: 15px;
      line-height: 1.7;
      color: var(--text-secondary);
    }

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

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

    button, .btn {
      cursor: pointer;
      font-family: var(--font-sans);
      font-weight: 700;
      transition: all var(--transition);
      display: inline-flex;
      align-items: center;
      justify-content: center;
      border: none;
      outline: none;
    }

    /* 导航 */
    .navbar {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      height: 72px;
      display: flex;
      align-items: center;
      background: transparent;
      transition: background 0.3s ease, backdrop-filter 0.3s ease;
      border-bottom: 1px solid transparent;
    }

    .navbar.scrolled {
      background: rgba(10,14,39,0.85);
      backdrop-filter: blur(20px);
      border-bottom: 1px solid rgba(0,240,255,0.15);
    }

    .navbar-inner {
      display: flex;
      justify-content: space-between;
      align-items: center;
      width: 100%;
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 24px;
    }

    .logo {
      font-size: 28px;
      font-weight: 800;
      color: var(--primary);
      font-family: var(--font-english);
      letter-spacing: 2px;
      text-shadow: 0 0 15px var(--primary-glow);
      display: flex;
      align-items: center;
      gap: 4px;
    }
    .logo span {
      color: var(--text-primary);
      font-family: var(--font-sans);
      font-size: 24px;
      margin-left: 8px;
    }

    .nav-links {
      display: flex;
      gap: 32px;
      align-items: center;
    }

    .nav-links a {
      font-size: 15px;
      font-weight: 500;
      color: var(--text-secondary);
      position: relative;
      padding: 4px 0;
      transition: color var(--transition);
    }

    .nav-links a:hover,
    .nav-links a.active {
      color: var(--primary);
    }

    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: -4px;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--primary);
      box-shadow: 0 0 12px var(--primary);
      transition: width var(--transition);
    }

    .nav-links a:hover::after,
    .nav-links a.active::after {
      width: 100%;
    }

    .btn-primary {
      background: var(--primary);
      color: var(--bg-deep);
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      box-shadow: 0 0 24px var(--primary-glow);
      font-weight: 700;
    }

    .btn-primary:hover {
      box-shadow: 0 0 36px rgba(0,240,255,0.75);
      transform: translateY(-2px);
    }

    .btn-ghost {
      background: transparent;
      border: 1px solid rgba(0,240,255,0.5);
      color: var(--primary);
      padding: 12px 28px;
      border-radius: var(--radius-btn);
    }

    .btn-ghost:hover {
      background: rgba(0,240,255,0.08);
      border-color: var(--primary);
    }

    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
      background: transparent;
      border: none;
    }
    .hamburger span {
      width: 28px;
      height: 2px;
      background: var(--primary);
      display: block;
      transition: 0.3s;
    }

    /* 移动端导航 */
    .mobile-menu {
      position: fixed;
      top: 0;
      right: -100%;
      width: 100%;
      height: 100vh;
      background: var(--bg-darker);
      backdrop-filter: blur(25px);
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      gap: 40px;
      z-index: 2000;
      transition: right 0.35s ease-out;
    }
    .mobile-menu.open {
      right: 0;
    }
    .mobile-menu a {
      font-size: 20px;
      color: var(--text-primary);
      font-weight: 600;
      letter-spacing: 1px;
    }
    .mobile-close {
      position: absolute;
      top: 24px;
      right: 24px;
      font-size: 32px;
      background: none;
      border: none;
      color: var(--primary);
      cursor: pointer;
    }

    /* 区块间距 */
    section {
      padding: 100px 0;
    }
    @media (max-width: 768px) {
      section {
        padding: 64px 0;
      }
    }

    /* Hero */
    .hero {
      min-height: 100vh;
      display: flex;
      align-items: center;
      background: radial-gradient(circle at 20% 30%, rgba(0,240,255,0.08) 0%, transparent 50%),
                  url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      background-blend-mode: overlay;
      position: relative;
      padding-top: 72px;
    }

    .hero-content {
      max-width: 700px;
      z-index: 2;
    }

    .hero h1 {
      text-shadow: 0 0 25px var(--primary-glow);
      margin-bottom: 24px;
    }

    .hero .subtitle {
      font-size: 20px;
      color: var(--text-secondary);
      margin-bottom: 16px;
      font-weight: 400;
    }

    .hero .desc {
      font-size: 16px;
      color: var(--text-muted);
      margin-bottom: 40px;
      max-width: 500px;
    }

xiv;
    .hero-buttons {
      display: flex;
      gap: 20px;
      flex-wrap: wrap;
    }

    /* 核心优势 错落卡片 */
    .features-grid {
      display: flex;
      justify-content: center;
      align-items: flex-start;
      gap: 32px;
      flex-wrap: wrap;
      margin-top: 48px;
    }

    .feature-card {
      background: var(--glass-bg);
      backdrop-filter: blur(12px);
      border: 1px solid var(--glass-border);
      border-radius: var(--radius-card);
      padding: 32px 24px;
      flex: 1;
      min-width: 260px;
      max-width: 340px;
      transition: transform 0.3s ease, box-shadow 0.3s ease;
      position: relative;
      top: 0;
    }
    .feature-card.center {
      transform: scale(1.05);
      border-color: rgba(0,240,255,0.25);
      box-shadow: 0 8px 30px rgba(0,240,255,0.1);
    }
    .feature-card:hover {
      transform: translateY(-10px);
      box-shadow: 0 12px 32px rgba(0,240,255,0.15);
    }
    .feature-icon {
      font-size: 32px;
      color: var(--primary);
      margin-bottom: 20px;
      text-shadow: 0 0 15px var(--primary);
    }
    .feature-card h3 {
      margin-bottom: 12px;
    }

    /* 服务体系 2x2 grid */
    .services-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 24px;
      margin-top: 48px;
    }

    .service-card {
      background: var(--glass-bg);
      backdrop-filter: blur(12px);
      border: 1px solid rgba(0,240,255,0.15);
      border-radius: var(--radius-card);
      padding: 36px 28px;
      box-shadow: 0 0 0 transparent;
      transition: all 0.3s ease;
    }
    .service-card:hover {
      border-color: var(--primary);
      box-shadow: 0 0 25px var(--primary-glow);
    }
    .service-card ul {
      list-style: none;
      margin: 16px 0;
      color: var(--text-secondary);
      font-size: 14px;
    }
    .service-card li {
      margin-bottom: 8px;
      display: flex;
      align-items: baseline;
      gap: 8px;
    }
    .service-link {
      color: var(--primary);
      font-weight: 600;
      font-size: 14px;
      margin-top: 12px;
      display: inline-block;
    }

    /* 案例横向滚动 */
    .cases-scroll {
      display: flex;
      gap: 24px;
      overflow-x: auto;
      padding: 24px 0 32px;
      scrollbar-width: thin;
      scrollbar-color: var(--primary) transparent;
    }
    .cases-scroll::-webkit-scrollbar {
      height: 4px;
    }
    .cases-scroll::-webkit-scrollbar-thumb {
      background: var(--primary);
      border-radius: 4px;
    }
    .case-card {
      min-width: 340px;
      background: rgba(255,255,255,0.03);
      border: 1px solid rgba(255,255,255,0.08);
      border-radius: var(--radius-card);
      overflow: hidden;
      flex-shrink: 0;
      transition: all 0.3s;
    }
    .case-card img {
      height: 200px;
      object-fit: cover;
      transition: transform 0.4s;
    }
    .case-card:hover img {
      transform: scale(1.06);
    }
    .case-info {
      padding: 20px;
    }
    .badge {
      background: var(--accent);
      color: #fff;
      font-size: 12px;
      padding: 4px 12px;
      border-radius: 20px;
      display: inline-block;
      font-weight: 600;
    }

    /* FAQ */
    .faq-item {
      border-bottom: 1px solid rgba(255,255,255,0.1);
      padding: 5px 0;
    }
    .faq-question {
      display: flex;
      justify-content: space-between;
      align-items: center;
      padding: 20px 0;
      cursor: pointer;
      font-weight: 600;
      color: var(--text-primary);
      transition: 0.2s;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease-out;
      color: var(--text-secondary);
      font-size: 15px;
      padding-left: 16px;
      border-left: 3px solid transparent;
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding-bottom: 20px;
      border-left-color: var(--primary);
      box-shadow: 0 0 12px var(--primary-glow);
    }
    .faq-icon {
      font-size: 22px;
      color: var(--primary);
    }

    /* CTA 尾屏 */
    .cta-section {
      background: var(--bg-darker);
      text-align: center;
    }
    .contact-form {
      max-width: 500px;
      margin: 32px auto 0;
      display: flex;
      flex-direction: column;
      gap: 20px;
    }
    input, select, textarea {
      background: rgba(255,255,255,0.05);
      border: 1px solid rgba(255,255,255,0.12);
      border-radius: var(--radius-btn);
      padding: 14px 16px;
      color: #fff;
      font-family: var(--font-sans);
    }
    input:focus, select:focus {
      border-color: var(--primary);
      box-shadow: 0 0 14px var(--primary-glow);
    }

    footer {
      background: #060918;
      border-top: 1px solid rgba(0,240,255,0.08);
      padding: 60px 0 24px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr;
      gap: 40px;
    }

    @media (max-width: 1024px) {
      .features-grid { justify-content: center; }
      .feature-card.center { transform: none; }
    }
    @media (max-width: 768px) {
      h1 { font-size: 28px; }
      h2 { font-size: 24px; }
      .nav-links { display: none; }
      .hamburger { display: flex; }
      .services-grid { grid-template-columns:1fr; }
      .footer-grid { grid-template-columns:1fr; }
      .case-card { min-width: 280px; }
      .hero { background-position: 30% center; }
    }