/* roulang page: index */
:root {
      --primary-deep: #0A0E27;
      --accent-pink: #E94057;
      --accent-cyan: #00E5FF;
      --bg-light: #F5F6FA;
      --card-white: #FFFFFF;
      --text-main: #2D3748;
      --text-soft: #718096;
      --border-light: #E2E8F0;
      --shadow-card: 0 4px 20px rgba(0,0,0,0.06);
      --shadow-hover: 0 8px 30px rgba(0,0,0,0.12);
      --radius-md: 12px;
      --radius-sm: 8px;
      --max-width: 1280px;
      --transition: 0.25s ease;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    body {
      font-family: 'Inter', 'Noto Sans SC', sans-serif;
      font-weight: 400;
      font-size: 16px;
      line-height: 1.7;
      color: var(--text-main);
      background-color: var(--bg-light);
      -webkit-font-smoothing: antialiased;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: var(--transition);
    }
    button, .btn {
      cursor: pointer;
      font-family: inherit;
      font-weight: 600;
      border: none;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 6px;
      transition: var(--transition);
      border-radius: var(--radius-sm);
      padding: 12px 28px;
      font-size: 15px;
      letter-spacing: 0.3px;
      outline: none;
    }
    .container {
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 24px;
      width: 100%;
    }
    /* 导航 */
    .header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 90;
      background-color: rgba(10, 14, 39, 0.92);
      backdrop-filter: blur(10px);
      -webkit-backdrop-filter: blur(10px);
      border-bottom: 1px solid rgba(0, 229, 255, 0.25);
    }
    .nav {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 72px;
    }
    .logo {
      font-size: 28px;
      font-weight: 700;
      letter-spacing: 2px;
      color: white;
      position: relative;
      display: inline-block;
      line-height: 1.2;
      text-decoration: none;
    }
    .logo::after {
      content: '';
      position: absolute;
      left: 0;
      bottom: -4px;
      width: 60%;
      height: 3px;
      background: var(--accent-cyan);
      border-radius: 2px;
      box-shadow: 0 0 12px var(--accent-cyan);
    }
    .nav-links {
      display: flex;
      gap: 36px;
      align-items: center;
      list-style: none;
    }
    .nav-links a {
      color: #e2e8f0;
      font-weight: 500;
      font-size: 16px;
      position: relative;
      padding: 6px 0;
    }
    .nav-links a:hover {
      color: var(--accent-cyan);
    }
    .nav-cta {
      background: var(--accent-pink);
      color: white;
      border-radius: 40px;
      padding: 10px 24px;
      font-weight: 600;
    }
    .nav-cta:hover {
      background: #C81E3A;
    }
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      background: transparent;
      border: none;
      padding: 6px;
    }
    .hamburger span {
      width: 26px;
      height: 2.5px;
      background: white;
      transition: var(--transition);
    }
    /* 移动导航面板 */
    .mobile-menu {
      display: none;
      position: fixed;
      top: 72px;
      left: 0;
      width: 100%;
      background: rgba(10,14,39,0.98);
      backdrop-filter: blur(12px);
      flex-direction: column;
      padding: 32px;
      gap: 24px;
      z-index: 80;
    }
    .mobile-menu a {
      color: white;
      font-size: 18px;
      font-weight: 500;
    }
    /* 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;
      color: white;
      margin-top: 0;
    }
    .hero-overlay {
      position: absolute;
      top: 0; left: 0; right: 0; bottom: 0;
      background: linear-gradient(135deg, rgba(10,14,39,0.88) 0%, rgba(10,14,39,0.7) 100%);
      z-index: 1;
    }
    .hero-content {
      position: relative;
      z-index: 2;
      max-width: 720px;
      padding: 0 24px;
    }
    .hero h1 {
      font-size: clamp(36px, 5vw, 58px);
      font-weight: 700;
      line-height: 1.2;
      margin-bottom: 24px;
    }
    .hero-sub {
      font-size: 18px;
      opacity: 0.9;
      margin-bottom: 36px;
      max-width: 600px;
    }
    .btn-primary {
      background: var(--accent-pink);
      color: white;
    }
    .btn-primary:hover {
      background: #C81E3A;
    }
    .btn-outline {
      background: transparent;
      border: 1px solid var(--accent-cyan);
      color: var(--accent-cyan);
    }
    .btn-outline:hover {
      background: var(--accent-cyan);
      color: var(--primary-deep);
      border-color: var(--accent-cyan);
    }
    .hero-buttons {
      display: flex;
      gap: 18px;
      flex-wrap: wrap;
    }
    .light-dots {
      position: absolute;
      right: 40px;
      bottom: 100px;
      width: 200px;
      height: 200px;
      background: radial-gradient(circle, rgba(0,229,255,0.25) 5%, transparent 70%);
      z-index: 1;
      animation: pulse 3s infinite;
    }
    @keyframes pulse {
      0% { opacity: 0.4; transform: scale(1);}
      50% { opacity: 0.8; transform: scale(1.05);}
      100% { opacity: 0.4; transform: scale(1);}
    }

    section {
      padding: 100px 0;
    }
    .section-title {
      font-size: 36px;
      font-weight: 600;
      margin-bottom: 16px;
      color: var(--primary-deep);
    }

    /* 核心优势 - 左大图右三行 */
    .advantage-grid {
      display: flex;
      gap: 50px;
      align-items: center;
    }
    .adv-img {
      flex: 1;
      border-radius: var(--radius-md);
      overflow: hidden;
      box-shadow: var(--shadow-card);
    }
    .adv-list {
      flex: 1;
      display: flex;
      flex-direction: column;
      gap: 24px;
    }
    .adv-item {
      display: flex;
      gap: 18px;
      align-items: flex-start;
      padding-bottom: 20px;
      border-bottom: 1px solid var(--border-light);
    }
    .adv-icon {
      font-size: 28px;
      color: var(--accent-cyan);
    }
    /* 产品卡片网格 */
    .cards-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 28px;
    }
    .card {
      background: var(--card-white);
      border-radius: var(--radius-md);
      box-shadow: var(--shadow-card);
      overflow: hidden;
      transition: var(--transition);
    }
    .card:hover {
      transform: translateY(-5px);
      box-shadow: var(--shadow-hover);
    }
    .card-img {
      aspect-ratio: 16/9;
      object-fit: cover;
      width: 100%;
    }
    .card-body {
      padding: 22px 24px 28px;
    }
    .card h3 {
      font-size: 20px;
      margin-bottom: 8px;
    }
    .link-pink {
      color: var(--accent-pink);
      font-weight: 600;
      display: inline-flex;
      align-items: center;
    }
    /* 场景交替 */
    .scene-row {
      display: flex;
      align-items: center;
      gap: 50px;
      margin-bottom: 80px;
    }
    .scene-text {
      flex: 1;
    }
    .scene-img {
      flex: 1;
      border-radius: var(--radius-md);
      overflow: hidden;
      transition: var(--transition);
    }
    .scene-img:hover {
      transform: scale(1.02);
    }
    /* 数据墙 */
    .data-scroll {
      display: flex;
      gap: 24px;
      overflow-x: auto;
      padding-bottom: 12px;
      scrollbar-width: thin;
    }
    .data-card {
      min-width: 180px;
      background: #edf2f7;
      border-radius: var(--radius-sm);
      padding: 24px;
      text-align: center;
      transition: var(--transition);
    }
    .data-card:hover {
      background: white;
      box-shadow: var(--shadow-card);
    }
    .data-num {
      font-family: 'Rajdhani', sans-serif;
      font-size: 44px;
      font-weight: 600;
      color: var(--accent-cyan);
    }
    /* FAQ 手风琴 */
    .faq-item {
      border-bottom: 1px solid var(--border-light);
    }
    .faq-question {
      background: transparent;
      width: 100%;
      text-align: left;
      padding: 20px 0;
      font-weight: 600;
      font-size: 18px;
      display: flex;
      justify-content: space-between;
      align-items: center;
      color: var(--primary-deep);
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.35s ease;
      background: #f8fafc;
      padding: 0 20px;
      border-radius: 0 0 8px 8px;
    }
    .faq-answer p {
      padding: 12px 0;
    }
    .faq-icon {
      font-size: 22px;
      color: var(--accent-pink);
    }
    /* CTA banner */
    .cta-banner {
      background: var(--primary-deep);
      border-radius: var(--radius-md);
      text-align: center;
      padding: 70px 24px;
      position: relative;
      overflow: hidden;
    }
    .cta-glow {
      position: absolute;
      top: -30%;
      right: -10%;
      width: 250px;
      height: 250px;
      background: radial-gradient(circle, rgba(0,229,255,0.2) 0%, transparent 80%);
    }
    .footer {
      background: var(--primary-deep);
      color: #cbd5e0;
      padding: 60px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1.2fr 1fr;
      gap: 40px;
    }
    @media (max-width: 1024px) {
      .cards-grid { grid-template-columns: repeat(2, 1fr); }
      .advantage-grid { flex-direction: column; }
    }
    @media (max-width: 768px) {
      .nav-links, .nav-cta { display: none; }
      .hamburger { display: flex; }
      section { padding: 70px 0; }
      .hero h1 { font-size: 36px; }
      .cards-grid { grid-template-columns: 1fr; }
      .scene-row { flex-direction: column; }
      .footer-grid { grid-template-columns: 1fr; }
      .data-scroll { gap: 14px; }
    }