/* roulang page: index */
:root {
      --deep-space: #0A0E27;
      --dark-bg: #1A1F3A;
      --fire-red: #FF4D2E;
      --electric-cyan: #00E5FF;
      --white-alpha-03: rgba(255, 255, 255, 0.03);
      --white-alpha-08: rgba(255, 255, 255, 0.08);
      --white-alpha-15: rgba(255, 255, 255, 0.15);
      --text-primary: #F0F0F0;
      --text-muted: #A0A5B5;
      --card-bg: rgba(255, 255, 255, 0.03);
      --card-border: rgba(255, 255, 255, 0.08);
      --card-hover-border: #00E5FF;
      --radius-lg: 16px;
      --radius-pill: 50px;
      --shadow-card: 0 8px 32px rgba(0, 0, 0, 0.4);
      --glow-red: 0 0 20px rgba(255, 77, 46, 0.5);
      --glow-cyan: 0 0 15px rgba(0, 229, 255, 0.3);
      --transition: all 0.25s ease;
    }

    * {
      box-sizing: border-box;
    }

    body {
      font-family: 'PingFang SC', 'Microsoft YaHei', 'Inter', 'Rajdhani', sans-serif;
      background: linear-gradient(135deg, var(--deep-space) 0%, #1A1F3A 100%);
      color: var(--text-primary);
      line-height: 1.7;
      margin: 0;
      overflow-x: hidden;
      position: relative;
    }

    /* Grid background texture */
    body::before {
      content: "";
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      background-image: 
        linear-gradient(rgba(0, 229, 255, 0.03) 1px, transparent 1px),
        linear-gradient(90deg, rgba(0, 229, 255, 0.03) 1px, transparent 1px);
      background-size: 40px 40px;
      pointer-events: none;
      z-index: -1;
    }

    a {
      text-decoration: none;
      color: var(--electric-cyan);
      transition: var(--transition);
    }
    a:hover {
      color: var(--fire-red);
    }

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

    /* Typography */
    h1, h2, h3, .h1, .h2, .h3 {
      font-weight: 700;
      letter-spacing: -0.5px;
    }

    .gradient-text {
      background: linear-gradient(to right, var(--fire-red), var(--electric-cyan));
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
    }

    /* Top Bar */
    .top-bar {
      background: rgba(10, 14, 39, 0.75);
      backdrop-filter: blur(8px);
      font-size: 13px;
      height: 36px;
      border-bottom: 1px solid rgba(255,255,255,0.05);
    }
    .top-bar .domain {
      color: var(--electric-cyan);
      font-weight: 600;
    }
    .top-bar .consult-btn {
      background: transparent;
      border: 1px solid var(--fire-red);
      color: var(--fire-red);
      padding: 2px 12px;
      border-radius: 20px;
      font-size: 12px;
      transition: var(--transition);
    }
    .top-bar .consult-btn:hover {
      background: var(--fire-red);
      color: #fff;
      box-shadow: var(--glow-red);
    }

    /* Main Nav */
    .main-nav {
      background: rgba(10, 14, 39, 0.8);
      backdrop-filter: blur(12px);
      height: 72px;
      border-bottom: 1px solid rgba(255,255,255,0.05);
      transition: background 0.3s, backdrop-filter 0.3s;
    }
    .main-nav.scrolled {
      background: rgba(10, 14, 39, 0.95);
      backdrop-filter: blur(20px);
      box-shadow: 0 4px 20px rgba(0,0,0,0.5);
    }
    .navbar-brand {
      font-family: 'Rajdhani', 'PingFang SC', sans-serif;
      font-weight: 700;
      font-size: 1.8rem;
      color: #fff !important;
      display: flex;
      align-items: center;
      gap: 8px;
    }
    .logo-icon {
      font-size: 2rem;
      color: var(--fire-red);
      filter: drop-shadow(0 0 8px var(--fire-red));
    }
    .nav-link {
      color: #ccc !important;
      font-weight: 500;
      margin: 0 10px;
      position: relative;
      transition: var(--transition);
    }
    .nav-link::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 50%;
      transform: translateX(-50%);
      width: 0;
      height: 2px;
      background: var(--electric-cyan);
      transition: width 0.3s ease;
      box-shadow: 0 0 10px var(--electric-cyan);
    }
    .nav-link:hover::after,
    .nav-link.active::after {
      width: 70%;
    }
    .nav-link:hover {
      color: #fff !important;
    }
    .navbar-toggler {
      border-color: rgba(255,255,255,0.3);
    }
    .navbar-toggler-icon {
      background-image: url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 30 30'%3e%3cpath stroke='rgba(255, 255, 255, 0.7)' stroke-linecap='round' stroke-miterlimit='10' stroke-width='2' d='M4 7h22M4 15h22M4 23h22'/%3e%3c/svg%3e");
    }

    /* Buttons */
    .btn-primary-custom {
      background: var(--fire-red);
      color: white;
      border-radius: var(--radius-pill);
      padding: 12px 28px;
      font-weight: 600;
      border: none;
      box-shadow: var(--glow-red);
      transition: var(--transition);
    }
    .btn-primary-custom:hover {
      background: #ff5a3e;
      box-shadow: 0 0 30px rgba(255,77,46,0.8);
      transform: scale(1.05);
      color: white;
    }
    .btn-outline-cyan {
      background: transparent;
      border: 1px solid var(--electric-cyan);
      color: var(--electric-cyan);
      border-radius: var(--radius-pill);
      padding: 12px 28px;
      font-weight: 600;
      transition: var(--transition);
    }
    .btn-outline-cyan:hover {
      background: rgba(0,229,255,0.1);
      box-shadow: var(--glow-cyan);
      color: var(--electric-cyan);
    }

    /* Glass card */
    .glass-card {
      background: var(--card-bg);
      backdrop-filter: blur(12px);
      border: 1px solid var(--card-border);
      border-radius: var(--radius-lg);
      box-shadow: var(--shadow-card);
      transition: var(--transition);
    }
    .glass-card:hover {
      border-color: var(--card-hover-border);
      box-shadow: 0 0 25px rgba(0,229,255,0.2), var(--shadow-card);
      transform: translateY(-4px);
    }

    /* Hero */
    .hero-bg-img {
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      position: relative;
      border-radius: 20px;
      overflow: hidden;
      min-height: 300px;
    }
    .hero-data-card {
      background: rgba(10,14,39,0.7);
      backdrop-filter: blur(16px);
      border: 1px solid rgba(255,255,255,0.15);
      border-radius: 16px;
      color: white;
    }
    .stat-number {
      font-family: 'Rajdhani', sans-serif;
      font-weight: 700;
      font-size: 2.2rem;
      color: var(--electric-cyan);
      text-shadow: 0 0 15px var(--electric-cyan);
    }

    /* Advantages grid 2x3 offset */
    .adv-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 30px;
    }
    .adv-item:nth-child(1), .adv-item:nth-child(2) {
      /* first row 2 items centered? we use grid placement */
    }
    /* make first row only 2 items by spanning */
    .adv-item.row1 {
      grid-column: span 1;
    }
    /* adjust placement for asymmetric look: row1 items placed in col 1 and 3? We'll use manual classes */
    @media(min-width: 992px) {
      .adv-grid {
        grid-template-columns: repeat(3, 1fr);
      }
      .adv-item:nth-child(1) { grid-column: 1 / 2; }
      .adv-item:nth-child(2) { grid-column: 3 / 4; }
      .adv-item:nth-child(3) { grid-column: 1 / 2; }
      .adv-item:nth-child(4) { grid-column: 2 / 3; }
      .adv-item:nth-child(5) { grid-column: 3 / 4; }
    }

    /* Cases waterfall */
    .cases-masonry {
      column-count: 3;
      column-gap: 24px;
    }
    .case-card {
      break-inside: avoid;
      margin-bottom: 24px;
      background: var(--card-bg);
      backdrop-filter: blur(12px);
      border-radius: var(--radius-lg);
      overflow: hidden;
      border: 1px solid var(--card-border);
      transition: var(--transition);
    }
    .case-card:hover {
      border-color: var(--electric-cyan);
    }
    .case-img-wrap {
      position: relative;
      overflow: hidden;
    }
    .case-img-wrap img {
      transition: transform 0.4s ease;
      width: 100%;
    }
    .case-card:hover .case-img-wrap img {
      transform: scale(1.08);
    }
    .case-overlay {
      position: absolute;
      bottom: 0;
      left: 0;
      width: 100%;
      background: linear-gradient(transparent, rgba(10,14,39,0.9));
      padding: 20px 16px 12px;
    }

    /* Solution table */
    .solution-table {
      width: 100%;
      border-collapse: separate;
      border-spacing: 0 8px;
    }
    .solution-table th {
      background: rgba(0,229,255,0.1);
      color: var(--electric-cyan);
      font-weight: 600;
      padding: 12px 16px;
      border-radius: 8px 8px 0 0;
    }
    .solution-table td {
      background: rgba(255,255,255,0.03);
      padding: 12px 16px;
      vertical-align: middle;
    }
    .highlight-row td {
      background: rgba(255,77,46,0.1);
      border-left: 3px solid var(--fire-red);
    }

    /* FAQ Accordion */
    .accordion-button {
      background: rgba(255,255,255,0.03);
      color: #ddd;
      font-weight: 600;
      border: 1px solid rgba(255,255,255,0.05);
      border-radius: 12px !important;
      margin-bottom: 8px;
      transition: var(--transition);
    }
    .accordion-button:not(.collapsed) {
      background: rgba(0,229,255,0.05);
      color: white;
      border-left: 3px solid var(--electric-cyan);
    }
    .accordion-body {
      background: rgba(0,0,0,0.2);
      color: #b0b5c5;
      border-radius: 0 0 12px 12px;
    }

    /* CTA Banner */
    .cta-banner {
      background: linear-gradient(135deg, #0A0E27, #2a1a2e);
      position: relative;
      overflow: hidden;
    }
    .cta-banner::before {
      content: "";
      position: absolute;
      top: -50%;
      right: -20%;
      width: 400px;
      height: 400px;
      background: radial-gradient(circle, rgba(255,77,46,0.25) 0%, transparent 70%);
      border-radius: 50%;
    }

    /* Footer */
    .footer {
      background: #050A18;
      color: #8a8f9a;
    }
    .footer a {
      color: #aaa;
    }
    .footer a:hover {
      color: var(--electric-cyan);
    }

    @media (max-width: 768px) {
      h1 { font-size: 32px; }
      h2 { font-size: 26px; }
      .cases-masonry { column-count: 2; }
      .adv-grid {
        grid-template-columns: 1fr;
      }
      .adv-item:nth-child(n) { grid-column: auto; }
      .navbar-brand { font-size: 1.5rem; }
    }
    @media (max-width: 520px) {
      .cases-masonry { column-count: 1; }
    }