/* roulang page: index */
:root {
      --primary-deep: #0A0E27;
      --accent-cyan: #00F0FF;
      --accent-red: #FF3D00;
      --bg-light: #FAFAFC;
      --card-white: #FFFFFF;
      --text-main: #1A1A2E;
      --text-muted: #5A5A72;
      --text-on-dark: #FFFFFF;
      --border-light: rgba(10, 14, 39, 0.08);
      --shadow-card: 0 2px 12px rgba(10, 14, 39, 0.06);
      --shadow-glow: 0 8px 28px rgba(0, 240, 255, 0.18);
      --radius-card: 16px;
      --radius-inner: 10px;
      --radius-btn: 30px;
      --radius-sec-btn: 8px;
      --font-zh: 'PingFang SC', 'Microsoft YaHei', 'Noto Sans SC', sans-serif;
      --font-en: 'Inter', 'SF Pro Display', system-ui;
      --section-gap: 100px;
    }

    * {
      box-sizing: border-box;
    }

    body {
      font-family: var(--font-zh);
      font-weight: 400;
      line-height: 1.7;
      color: var(--text-main);
      background-color: var(--bg-light);
      margin: 0;
      -webkit-font-smoothing: antialiased;
    }

    h1, h2, h3, h4 {
      font-family: var(--font-zh);
      letter-spacing: -0.02em;
    }

    .font-en, .data-number, .counter {
      font-family: var(--font-en);
    }

    /* Bootstrap overrides */
    .container {
      max-width: 1280px;
      padding-left: 24px;
      padding-right: 24px;
    }

    .row {
      --bs-gutter-x: 24px;
    }

    .btn {
      border-radius: var(--radius-btn);
      padding: 12px 28px;
      font-weight: 600;
      transition: all 0.25s ease;
      border: none;
    }

    .btn-primary {
      background: linear-gradient(15deg, var(--accent-cyan), var(--primary-deep));
      color: white;
      border: none;
    }

    .btn-primary:hover {
      background: linear-gradient(45deg, var(--accent-cyan), var(--primary-deep));
      box-shadow: 0 4px 18px var(--accent-cyan);
      transform: scale(1.03);
      color: white;
    }

    .btn-outline-primary {
      border: 1px solid var(--accent-cyan);
      color: var(--accent-cyan);
      background: transparent;
    }

    .btn-outline-primary:hover {
      background: rgba(0, 240, 255, 0.15);
      border-color: var(--accent-cyan);
      color: var(--accent-cyan);
    }

    .btn-secondary-custom {
      background: transparent;
      border: 1px solid rgba(255,255,255,0.4);
      color: white;
      border-radius: var(--radius-btn);
      padding: 12px 28px;
      font-weight: 500;
    }
    .btn-secondary-custom:hover {
      background: rgba(255,255,255,0.1);
      border-color: white;
      color: white;
    }

    .card {
      border: none;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-card);
      background: var(--card-white);
      transition: transform 0.25s, box-shadow 0.25s;
    }
    .card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-glow);
    }

    /* Navbar */
    .navbar {
      background: rgba(255,255,255,0.85);
      backdrop-filter: blur(12px);
      height: 64px;
      box-shadow: none;
      transition: background 0.2s, box-shadow 0.2s;
    }
    .navbar.scrolled {
      background: white;
      box-shadow: 0 1px 8px rgba(0,0,0,0.05);
    }
    .navbar-brand {
      font-family: var(--font-zh);
      font-weight: 700;
      font-size: 24px;
      background: linear-gradient(135deg, var(--accent-cyan), #0A0E27);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
      letter-spacing: 0.5px;
    }
    .navbar-nav .nav-link {
      color: var(--text-main) !important;
      font-weight: 500;
      margin: 0 4px;
      position: relative;
      transition: color 0.2s;
    }
    .navbar-nav .nav-link::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 50%;
      width: 0;
      height: 2px;
      background: var(--accent-cyan);
      transition: width 0.25s ease, left 0.25s ease;
    }
    .navbar-nav .nav-link:hover::after,
    .navbar-nav .nav-link.active::after {
      width: 100%;
      left: 0;
    }
    .navbar-nav .nav-link.active {
      color: var(--accent-cyan) !important;
    }
    .btn-nav {
      background: linear-gradient(15deg, var(--accent-cyan), var(--primary-deep));
      color: white !important;
      border-radius: 30px;
      padding: 8px 20px !important;
      font-weight: 600;
      box-shadow: 0 2px 8px rgba(0,240,255,0.3);
    }
    .btn-nav:hover {
      box-shadow: 0 4px 14px var(--accent-cyan);
    }

    /* Hero */
    .hero-section {
      padding-top: 120px;
      padding-bottom: 80px;
      background: white;
    }
    .hero-left {
      padding-right: 60px;
    }
    .hero-tag {
      color: var(--accent-cyan);
      font-weight: 600;
      font-size: 14px;
      letter-spacing: 1px;
      margin-bottom: 16px;
    }
    .hero-title {
      font-size: 48px;
      font-weight: 800;
      line-height: 1.15;
      color: var(--primary-deep);
      margin-bottom: 24px;
    }
    .hero-sub {
      font-size: 18px;
      color: var(--text-muted);
      max-width: 480px;
      margin-bottom: 32px;
    }
    .hero-data-item {
      font-family: var(--font-en);
      font-weight: 700;
      color: var(--primary-deep);
    }
    .hero-right-img {
      width: 100%;
      height: auto;
      border-radius: 24px;
      filter: drop-shadow(0 16px 24px rgba(0,240,255,0.15));
    }

    /* Hex Grid */
    .hex-grid {
      display: flex;
      flex-wrap: wrap;
      justify-content: center;
      gap: 24px;
    }
    .hex-item {
      width: 180px;
      height: 200px;
      background: white;
      clip-path: polygon(25% 0%, 75% 0%, 100% 50%, 75% 100%, 25% 100%, 0% 50%);
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      text-align: center;
      padding: 20px;
      transition: 0.2s;
      box-shadow: 0 4px 12px rgba(0,0,0,0.04);
    }
    .hex-item:hover {
      border: 2px solid var(--accent-cyan);
      box-shadow: 0 0 18px rgba(0,240,255,0.25);
    }
    .hex-icon {
      font-size: 28px;
      color: var(--accent-cyan);
      margin-bottom: 8px;
    }
    .hex-title {
      font-weight: 700;
      font-size: 16px;
    }

    /* Cases waterfall */
    .case-col-1 { margin-top: 0; }
    .case-col-2 { margin-top: 40px; }
    .case-col-3 { margin-top: 20px; }
    .case-img {
      width: 100%;
      aspect-ratio: 16/9;
      object-fit: cover;
      border-radius: var(--radius-inner);
    }
    .case-tag {
      background: rgba(0,240,255,0.15);
      color: var(--primary-deep);
      font-size: 12px;
      padding: 2px 10px;
      border-radius: 20px;
    }

    /* Table compare */
    .compare-card {
      background: white;
      border-radius: 20px;
      padding: 32px 20px;
      text-align: center;
      box-shadow: 0 6px 18px rgba(0,0,0,0.04);
    }
    .compare-highlight {
      border: 2px solid var(--accent-red);
      box-shadow: 0 10px 24px rgba(255,61,0,0.15);
    }
    .price {
      font-size: 36px;
      font-weight: 700;
      font-family: var(--font-en);
    }

    /* Dashboard */
    .dashboard {
      background: var(--primary-deep);
      background-image: radial-gradient(circle at 20% 30%, rgba(0,240,255,0.08) 0%, transparent 40%);
    }
    .counter {
      font-size: 48px;
      font-weight: 700;
      color: var(--accent-cyan);
      font-feature-settings: "tnum";
    }

    /* FAQ */
    .accordion-button {
      background: white;
      font-weight: 600;
      font-size: 18px;
      color: var(--text-main);
      box-shadow: none;
    }
    .accordion-button:not(.collapsed) {
      background: #F0F4FF;
      color: var(--primary-deep);
    }
    .accordion-button::after {
      background-image: none;
      content: "+";
      font-weight: 700;
      color: var(--accent-cyan);
      font-size: 24px;
      transition: 0.2s;
    }
    .accordion-button:not(.collapsed)::after {
      content: "−";
    }

    .cta-section {
      background: var(--primary-deep);
    }

    footer {
      background: var(--primary-deep);
      border-top: 3px solid var(--accent-cyan);
    }
    .footer-link {
      color: #8A8A9A;
      text-decoration: none;
    }
    .footer-link:hover {
      color: var(--accent-cyan);
    }

    @media (max-width: 992px) {
      .hero-left { padding-right: 0; }
      .hex-item { width: 150px; height: 170px; }
      .case-col-2, .case-col-3 { margin-top: 0; }
    }
    @media (max-width: 768px) {
      .hero-title { font-size: 36px; }
      .compare-scroll { overflow-x: auto; }
    }