/* roulang page: index */
:root {
      --primary-deep: #0A0E27;
      --accent-cyan: #00F0FF;
      --accent-magenta: #FF3CAC;
      --bg-light: #FAFAFC;
      --deep-bg: #060B1C;
      --text-main: #1A1A2E;
      --text-muted: #5A5A72;
      --white: #FFFFFF;
      --border-subtle: rgba(10, 14, 39, 0.08);
      --shadow-card: 0 8px 28px rgba(10, 14, 39, 0.04);
      --shadow-hover: 0 16px 36px rgba(0, 240, 255, 0.12);
      --radius-card: 20px;
      --radius-btn: 50px;
      --transition-bounce: 0.25s cubic-bezier(0.25, 0.8, 0.25, 1.2);
      --font-h1: 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', sans-serif;
      --font-body: 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
    }

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

    html {
      scroll-behavior: smooth;
      background-color: var(--bg-light);
    }

    body {
      font-family: var(--font-body);
      line-height: 1.7;
      color: var(--text-main);
      background-color: var(--bg-light);
      overflow-x: hidden;
    }

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

    a {
      text-decoration: none;
      color: inherit;
      transition: 0.2s ease;
    }

    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 28px;
    }

    /* 导航系统 */
    .main-nav {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 999;
      padding: 16px 0;
      background: transparent;
      backdrop-filter: blur(0px);
      transition: background 0.25s ease, backdrop-filter 0.3s, box-shadow 0.3s;
    }

    .main-nav.scrolled {
      background: rgba(250, 250, 252, 0.88);
      backdrop-filter: blur(17px);
      box-shadow: 0 1px16px rgba(0,0,0,0.03);
      border-bottom: 1px solid var(--border-subtle);
    }

    .main-nav.scrolled .nav-logo,
    .main-nav.scrolled .nav-links a {
      color: var(--text-main);
    }

    .main-nav.scrolled .nav-cta {
      background: var(--accent-cyan);
      color: #0A0E27;
    }

    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 28px;
    }

    .nav-logo {
      display: flex;
      align-items: center;
      gap: 8px;
      font-family: var(--font-h1);
      font-weight: 700;
      font-size: 22px;
      letter-spacing: 1px;
      color: white;
      transition: color 0.25s;
      white-space: nowrap;
    }
    .nav-logo i {
      font-size: 26px;
      background: linear-gradient(135deg, #00F0FF, #7B2FFF);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
    }

    .nav-links {
      display: flex;
      align-items: center;
      gap: 38px;
      font-weight: 500;
      white-space: nowrap;
    }

    .nav-links a {
      color: rgba(255,255,255,0.9);
      font-size: 15px;
      transition: 0.2s;
    }
    .nav-links a:hover {
      color: var(--accent-cyan);
    }
    .main-nav.scrolled .nav-links a:hover {
      color: var(--accent-cyan);
    }

    .nav-cta {
      background: transparent;
      border: 1.5px solid var(--accent-cyan);
      color: white;
      padding: 10px 26px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 14px;
      transition: 0.25s;
      white-space: nowrap;
    }
    .nav-cta:hover {
      background: var(--accent-cyan);
      color: #0A0E27;
      box-shadow: 0 0 22px rgba(0,240,255,0.4);
    }

    .mobile-menu-btn {
      display: none;
      background: transparent;
      border: none;
      color: white;
      font-size: 24px;
    }
    .main-nav.scrolled .mobile-menu-btn {
      color: var(--text-main);
    }

    /* 移动底部导航 */
    .mobile-bottom-nav {
      display: none;
    }

    /* Hero */
    .hero {
      background: var(--primary-deep);
      background-image: radial-gradient(circle at 25% 30%, rgba(0,240,255,0.06) 0%, transparent 45%);
      position: relative;
      padding: 160px 0 120px;
      overflow: hidden;
      color: white;
    }

    .hero-grid {
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 45px;
    }
    .hero-left {
      flex: 1;
    }
    .hero-right {
      flex: 1;
      position: relative;
      display: flex;
      justify-content: center;
    }

    .hero h1 {
      font-family: var(--font-h1);
      font-size: 58px;
      font-weight: 900;
      line-height: 1.15;
      background: linear-gradient(to right, #00F0FF, #C084FC);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
      margin-bottom: 18px;
    }
    .hero-sub {
      font-size: 22px;
      color: rgba(255,255,255,0.75);
      margin-bottom: 12px;
      font-weight: 400;
    }
    .hero-desc {
      color: #B0B8D1;
      margin: 24px 0 32px;
      font-size: 16px;
      max-width: 480px;
    }
    .btn-group {
      display: flex;
      gap: 15px;
      flex-wrap: wrap;
    }
    .btn-primary {
      background: linear-gradient(135deg, #00F0FF, #7B2FFF);
      color: white;
      border: none;
      padding: 14px 36px;
      border-radius: var(--radius-btn);
      font-weight: 700;
      font-size: 15px;
      transition: var(--transition-bounce);
      box-shadow: 0 8px 18px rgba(0,240,255,0.25);
    }
    .btn-primary:hover {
      box-shadow: 0 0 28px rgba(0,240,255,0.5);
      transform: scale(1.02);
    }
    .btn-outline {
      background: transparent;
      border: 1.5px solid var(--accent-cyan);
      color: white;
      padding: 14px 36px;
      border-radius: var(--radius-btn);
      font-weight: 600;
    }
    .btn-outline:hover {
      background: rgba(0,240,255,0.08);
    }
    .hero-stats {
      display: flex;
      gap: 45px;
      margin-top: 50px;
      flex-wrap: wrap;
    }
    .stat-digit {
      font-size: 36px;
      font-weight: 800;
      color: var(--accent-cyan);
    }

    /* 板块通用 */
    .section {
      padding: 110px 0;
    }
    .section h2 {
      font-family: var(--font-h1);
      font-size: 40px;
      font-weight: 700;
      margin-bottom: 18px;
      color: var(--text-main);
    }
    .section-sub {
      color: var(--text-muted);
      max-width: 660px;
      margin-bottom: 54px;
      font-size: 16px;
    }

    /* 优势卡片 */
    .grid-3 {
      display: grid;
      grid-template-columns: repeat(3,1fr);
      gap: 28px;
    }
    .adv-card {
      background: white;
      padding: 36px 28px;
      border-radius: 22px;
      box-shadow: var(--shadow-card);
      border: 1px solid var(--border-subtle);
      transition: all 0.2s ease;
    }
    .adv-card:hover {
      transform: translateY(-6px);
      box-shadow: 0 18px 35px rgba(0,240,255,0.12);
      border-color: rgba(0,240,255,0.35);
    }
    .icon-circle {
      width: 54px;
      height: 54px;
      background: rgba(0,240,255,0.08);
      border-radius: 16px;
      display: flex;
      align-items: center;
      justify-content: center;
      color: var(--accent-cyan);
      font-size: 24px;
      margin-bottom: 22px;
    }

    /* 产品左右交替 */
    .product-row {
      display: flex;
      align-items: center;
      gap: 64px;
      margin-bottom: 90px;
    }
    .product-img {
      flex: 1;
      border-radius: 24px;
      overflow: hidden;
      box-shadow: 0 16px 30px rgba(0,0,0,0.08);
    }
    .product-text {
      flex: 1;
    }

    /* 场景卡片 */
    .scene-card {
      background: white;
      border-radius: 20px;
      overflow: hidden;
      box-shadow: var(--shadow-card);
      transition: 0.25s;
    }
    .scene-card:hover { transform: translateY(-5px); }
    .scene-img { height: 200px; object-fit: cover; }
    .scene-content { padding: 26px; }

    /* 案例 */
    .case-grid {
      display: grid;
      grid-template-columns: repeat(4,1fr);
      gap: 22px;
    }
    .case-card {
      background: white;
      padding: 26px;
      border-radius: 18px;
      text-align: center;
    }

    /* 价格 */
    .pricing-grid {
      display: grid;
      grid-template-columns: repeat(3,1fr);
      gap: 26px;
    }
    .price-card {
      background: white;
      border-radius: 24px;
      padding: 42px 28px;
      box-shadow: 0 10px 25px rgba(0,0,0,0.03);
      border: 1px solid #eee;
      position: relative;
      transition: 0.25s;
    }
    .price-card.popular {
      border: 2px solid var(--accent-cyan);
      box-shadow: 0 18px 42px rgba(0,240,255,0.14);
      transform: scale(1.03);
    }
    .badge {
      background: #00F0FF;
      color: #0A0E27;
      padding: 4px 14px;
      border-radius: 20px;
      font-size: 12px;
      font-weight: 700;
    }

    /* FAQ */
    .faq-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 24px;
    }
    .faq-item {
      background: white;
      border-radius: 16px;
      padding: 22px;
      border-left: 3px solid transparent;
      transition: 0.2s;
    }
    .faq-item.active {
      border-left-color: var(--accent-cyan);
    }

    /* CTA深色 */
    .cta-dark {
      background: #060B1C;
      padding: 100px 0;
      text-align: center;
    }

    footer {
      background: #0A0E27;
      color: #B0B8D1;
      padding: 80px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 30px;
    }

    @media (max-width: 1024px) {
      .nav-links { display: none; }
      .mobile-menu-btn { display: block; }
      .hero h1 { font-size: 42px; }
      .grid-3, .pricing-grid { grid-template-columns: 1fr 1fr; }
      .case-grid { grid-template-columns: 1fr 1fr; }
      .product-row { flex-direction: column; }
    }

    @media (max-width: 768px) {
      .container { padding: 0 20px; }
      .mobile-bottom-nav {
        display: flex;
        position: fixed;
        bottom: 16px;
        left: 10px;
        right: 10px;
        background: white;
        border-radius: 30px;
        padding: 10px 18px;
        justify-content: space-around;
        box-shadow: 0 8px 28px rgba(0,0,0,0.15);
        z-index: 1000;
      }
      .hero { padding: 130px 0 90px; }
      .hero-grid { flex-direction: column; }
      .section { padding: 70px 0; }
      h2 { font-size: 32px !important; }
      .grid-3, .pricing-grid, .faq-grid { grid-template-columns: 1fr; }
      .price-card.popular { transform: scale(1); }
      .footer-grid { grid-template-columns: 1fr 1fr; }
    }

    .animate-up {
      opacity: 0;
      transform: translateY(30px);
      transition: 0.65s ease;
    }
    .animate-up.visible {
      opacity: 1;
      transform: translateY(0);
    }