/* roulang page: index */
:root {
      --bg-deep: #0A0E17;
      --bg-alt: #0D1320;
      --card-bg: #111827;
      --primary-neon: #00F0FF;
      --secondary-purple: #B347EA;
      --accent-gold: #FFB800;
      --text-main: #E0E8F0;
      --text-dim: #A0B0C0;
      --text-muted: #6B7A8D;
      --border-dim: rgba(0, 240, 255, 0.08);
      --border-glow: rgba(0, 240, 255, 0.25);
      --shadow-card: 0 4px 24px rgba(0,0,0,0.6);
      --shadow-hover: 0 8px 32px rgba(0, 240, 255, 0.2);
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-input: 6px;
      --font-family: "Inter", "PingFang SC", "Microsoft YaHei", sans-serif;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    html {
      scroll-behavior: smooth;
      scroll-padding-top: 80px;
    }
    body {
      font-family: var(--font-family);
      background-color: var(--bg-deep);
      color: var(--text-dim);
      line-height: 1.75;
      font-size: 1rem;
      -webkit-font-smoothing: antialiased;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: color 0.2s ease;
    }
    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 2rem;
    }
    @media (max-width: 768px) {
      .container {
        padding: 0 1.5rem;
      }
    }
    /* 导航栏 */
    header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      background-color: rgba(10, 14, 23, 0.92);
      backdrop-filter: blur(12px);
      border-bottom: 1px solid var(--border-glow);
      z-index: 1000;
      transition: background 0.3s;
    }
    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 72px;
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 2rem;
    }
    .logo {
      font-size: 1.7rem;
      font-weight: 800;
      letter-spacing: -0.02em;
      color: white;
      display: flex;
      align-items: center;
      gap: 0.5rem;
    }
    .logo i {
      color: var(--primary-neon);
      font-size: 2rem;
      text-shadow: 0 0 14px rgba(0,240,255,0.7);
    }
    .logo span {
      background: linear-gradient(135deg, #fff, #c0e0ff);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
    }
    .nav-menu {
      display: flex;
      align-items: center;
      gap: 2rem;
      list-style: none;
    }
    .nav-menu a {
      color: var(--text-dim);
      font-weight: 500;
      font-size: 0.95rem;
      padding: 0.4rem 0;
      position: relative;
      transition: 0.2s;
    }
    .nav-menu a:hover,
    .nav-menu a.active {
      color: white;
    }
    .nav-menu a.active {
      color: var(--primary-neon);
    }
    .nav-menu a::after {
      content: '';
      position: absolute;
      bottom: -4px;
      left: 0;
      width: 0;
      height: 3px;
      background: var(--primary-neon);
      box-shadow: 0 0 12px var(--primary-neon);
      transition: width 0.25s ease;
    }
    .nav-menu a:hover::after,
    .nav-menu a.active::after {
      width: 100%;
    }
    .btn-primary-nav {
      background: linear-gradient(135deg, #00F0FF, #0099CC);
      border: none;
      color: #fff !important;
      padding: 0.6rem 1.5rem;
      border-radius: var(--radius-btn);
      font-weight: 600;
      box-shadow: 0 0 14px rgba(0,240,255,0.4);
      transition: all 0.25s;
    }
    .btn-primary-nav:hover {
      box-shadow: 0 0 24px rgba(0,240,255,0.7);
      transform: translateY(-1px);
    }
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
      background: transparent;
      border: none;
    }
    .hamburger span {
      width: 26px;
      height: 2.5px;
      background: var(--primary-neon);
      border-radius: 2px;
    }
    @media (max-width: 1024px) {
      .nav-menu {
        gap: 1.2rem;
      }
    }
    @media (max-width: 768px) {
      .hamburger {
        display: flex;
      }
      .nav-menu {
        position: fixed;
        top: 72px;
        left: 0;
        width: 100%;
        background: #0D1320;
        flex-direction: column;
        padding: 2rem;
        gap: 1.5rem;
        transform: translateY(-150%);
        transition: transform 0.4s ease;
        border-bottom: 1px solid var(--border-glow);
        box-shadow: 0 12px 30px rgba(0,0,0,0.8);
      }
      .nav-menu.active {
        transform: translateY(0);
      }
    }
    /* 板块通用 */
    .section {
      padding: 5rem 0;
    }
    .section-alt {
      background-color: var(--bg-alt);
    }
    .section-title {
      font-size: clamp(1.8rem, 3.5vw, 2.5rem);
      font-weight: 700;
      color: white;
      margin-bottom: 1rem;
      text-align: center;
    }
    .section-sub {
      color: var(--text-dim);
      text-align: center;
      max-width: 640px;
      margin: 0 auto 3rem;
    }
    /* Hero */
    .hero {
      min-height: 100vh;
      display: flex;
      align-items: center;
      background: radial-gradient(circle at 30% 40%, rgba(0,240,255,0.08) 0%, transparent 50%), 
                  linear-gradient(135deg, #0A0E17 0%, #0D1320 100%);
      position: relative;
      overflow: hidden;
    }
    .hero-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 3rem;
      align-items: center;
    }
    .hero h1 {
      font-size: clamp(2.5rem, 5vw, 4rem);
      font-weight: 800;
      letter-spacing: -0.02em;
      color: white;
      line-height: 1.2;
      margin-bottom: 1.5rem;
    }
    .hero .highlight {
      color: var(--primary-neon);
      text-shadow: 0 0 20px rgba(0,240,255,0.55);
    }
    .hero p {
      font-size: 1.2rem;
      color: var(--text-dim);
      margin-bottom: 2.5rem;
    }
    .hero-buttons {
      display: flex;
      gap: 1.2rem;
      flex-wrap: wrap;
    }
    .btn {
      padding: 0.8rem 2rem;
      border-radius: var(--radius-btn);
      font-weight: 600;
      transition: all 0.25s;
      display: inline-block;
      text-align: center;
    }
    .btn-primary {
      background: linear-gradient(135deg, #00F0FF, #0099CC);
      color: #fff;
      box-shadow: 0 0 18px rgba(0,240,255,0.45);
      border: none;
    }
    .btn-primary:hover {
      box-shadow: 0 0 30px rgba(0,240,255,0.8);
      transform: translateY(-2px);
    }
    .btn-outline {
      border: 1px solid var(--primary-neon);
      color: var(--primary-neon);
      background: transparent;
    }
    .btn-outline:hover {
      background: rgba(0,240,255,0.1);
      box-shadow: 0 0 20px rgba(0,240,255,0.3);
    }
    .hero-image {
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      min-height: 380px;
      border-radius: 24px;
      border: 1px solid rgba(0,240,255,0.2);
      box-shadow: 0 0 40px rgba(0,240,255,0.15);
      position: relative;
    }
    @media (max-width: 768px) {
      .hero-grid {
        grid-template-columns: 1fr;
        text-align: center;
      }
      .hero-buttons {
        justify-content: center;
      }
    }
    /* 优势卡片 */
    .cards-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 2rem;
      margin-top: 2rem;
    }
    .advantage-card {
      background: var(--card-bg);
      border: 1px solid var(--border-dim);
      border-radius: var(--radius-card);
      padding: 2rem 1.5rem;
      transition: all 0.3s;
      text-align: center;
    }
    .advantage-card:hover {
      transform: translateY(-6px);
      border-color: var(--primary-neon);
      box-shadow: var(--shadow-hover);
    }
    .advantage-card i {
      font-size: 2.4rem;
      color: var(--primary-neon);
      margin-bottom: 1.2rem;
      text-shadow: 0 0 14px rgba(0,240,255,0.5);
    }
    .advantage-card h3 {
      color: white;
      font-weight: 600;
      margin-bottom: 0.8rem;
    }
    @media (max-width: 768px) {
      .cards-grid {
        grid-template-columns: 1fr;
      }
    }
    /* 产品服务 4卡片 */
    .service-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 2rem;
    }
    .service-card {
      background: var(--card-bg);
      border-radius: var(--radius-card);
      overflow: hidden;
      border: 1px solid var(--border-dim);
      transition: 0.3s;
      display: flex;
      flex-direction: column;
    }
    .service-card:hover {
      border-color: var(--primary-neon);
      box-shadow: var(--shadow-hover);
      transform: translateY(-4px);
    }
    .service-img {
      height: 180px;
      background-size: cover;
      background-position: center;
    }
    .service-body {
      padding: 1.5rem;
    }
    .service-body h3 {
      color: white;
      margin-bottom: 0.6rem;
    }
    .service-link {
      color: var(--primary-neon);
      margin-top: 1rem;
      display: inline-block;
      font-weight: 500;
    }
    @media (max-width: 768px) {
      .service-grid {
        grid-template-columns: 1fr;
      }
    }
    /* 应用场景 */
    .scene-row {
      display: flex;
      align-items: center;
      gap: 2.5rem;
      margin-bottom: 4rem;
    }
    .scene-reverse {
      flex-direction: row-reverse;
    }
    .scene-img {
      flex: 1;
      min-height: 280px;
      background-size: cover;
      background-position: center;
      border-radius: 16px;
      border: 1px solid rgba(179,71,234,0.3);
    }
    .scene-text {
      flex: 1;
    }
    .scene-text .tag {
      color: var(--primary-neon);
      font-weight: 600;
      margin-bottom: 0.5rem;
    }
    @media (max-width: 768px) {
      .scene-row, .scene-reverse {
        flex-direction: column;
      }
    }
    /* 案例数字 */
    .stats {
      display: flex;
      justify-content: center;
      gap: 3rem;
      flex-wrap: wrap;
      margin: 2.5rem 0;
    }
    .stat-item {
      text-align: center;
    }
    .stat-number {
      font-size: 2.8rem;
      font-weight: 800;
      color: var(--accent-gold);
      text-shadow: 0 0 18px rgba(255,184,0,0.5);
    }
    .logo-wall {
      display: flex;
      justify-content: center;
      gap: 3rem;
      flex-wrap: wrap;
      filter: grayscale(1);
      opacity: 0.7;
      margin-top: 2rem;
    }
    .logo-wall img {
      height: 40px;
      transition: 0.3s;
    }
    .logo-wall img:hover {
      filter: grayscale(0);
      opacity: 1;
    }
    /* 套餐 */
    .pricing-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 2rem;
    }
    .pricing-card {
      background: var(--card-bg);
      border-radius: var(--radius-card);
      padding: 2rem;
      border: 1px solid var(--border-dim);
      text-align: center;
      transition: 0.3s;
    }
    .pricing-card.recommend {
      border-color: var(--secondary-purple);
      box-shadow: 0 0 24px rgba(179,71,234,0.3);
      position: relative;
    }
    .badge {
      background: var(--secondary-purple);
      color: white;
      padding: 0.25rem 1rem;
      border-radius: 20px;
      font-size: 0.8rem;
    }
    .price {
      font-size: 2.5rem;
      color: var(--primary-neon);
      font-weight: 700;
    }
    @media (max-width: 768px) {
      .pricing-grid {
        grid-template-columns: 1fr;
      }
    }
    /* FAQ */
    .faq-item {
      background: #111827;
      border-radius: 10px;
      margin-bottom: 1rem;
      border-left: 5px solid transparent;
      transition: 0.2s;
    }
    .faq-item.active {
      border-left-color: var(--primary-neon);
      background: #151D2B;
    }
    .faq-question {
      padding: 1.2rem;
      font-weight: 600;
      color: white;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      padding: 0 1.2rem;
      color: var(--text-dim);
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding-bottom: 1.2rem;
    }
    /* CTA 横幅 */
    .cta-banner {
      background: #0D1320;
      text-align: center;
      padding: 4rem 2rem;
    }
    /* 页脚 */
    footer {
      background: #0A0E17;
      padding: 3rem 2rem;
      border-top: 1px solid rgba(0,240,255,0.2);
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 2rem;
    }
    @media (max-width: 768px) {
      .footer-grid {
        grid-template-columns: 1fr;
      }
    }