/* roulang page: index */
:root {
      --deep-blue: #0A0E27;
      --bg-gradient-start: #0F1429;
      --bg-gradient-end: #080c1f;
      --electric-blue: #1E6FFF;
      --electric-glow: rgba(30, 111, 255, 0.5);
      --accent-orange: #FF6B2C;
      --orange-glow: rgba(255, 107, 44, 0.5);
      --success-green: #00C48C;
      --card-bg: rgba(20, 27, 56, 0.65);
      --card-border: rgba(30, 111, 255, 0.2);
      --text-primary: #FFFFFF;
      --text-secondary: #B0B8D1;
      --text-muted: #6B7394;
      --surface-dark: #1E2340;
      --surface-light: #2A2F4A;
      --radius-lg: 16px;
      --radius-md: 12px;
      --radius-sm: 8px;
      --shadow-card: 0 8px 24px rgba(0, 0, 0, 0.5), inset 0 1px 0 rgba(255, 255, 255, 0.05);
      --shadow-glow-blue: 0 0 18px var(--electric-glow);
      --shadow-glow-hover: 0 0 28px var(--electric-glow);
      --font-title: "PingFang SC", "Microsoft YaHei", "苹方", "雅黑", system-ui, -apple-system, sans-serif;
      --font-mono: "SF Mono", "Fira Code", monospace;
        transition: all 0.25s ease;
    }

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

    body {
      font-family: var(--font-title);
      background: radial-gradient(circle at 30% 10%, #0F1429 0%, #060918 100%);
      color: var(--text-primary);
      line-height: 1.7;
      scroll-behavior: smooth;
      -webkit-font-smoothing: antialiased;
    }

    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 32px;
    }

    /* 细腻网格背景 */
    body::before {
      content: "";
      position: fixed;
      inset: 0;
      background-image: 
        linear-gradient(rgba(30, 111, 255, 0.03) 1px, transparent 1px),
        linear-gradient(90deg, rgba(30, 111, 255, 0.03) 1px, transparent 1px);
      background-size: 40px 40px;
      pointer-events: none;
      z-index: 0;
    }

    /* 导航 */
    .nav {
      position: sticky;
      top: 0;
      z-index: 50;
      background: rgba(10, 14, 39, 0.88);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
      border-bottom: 1px solid transparent;
      background-image: linear-gradient(rgba(10,14,39,0.9), rgba(10,14,39,0.9)), 
                        linear-gradient(90deg, var(--electric-blue), var(--accent-orange));
      background-origin: border-box;
      background-clip: padding-box, border-box;
      border-bottom: 1px solid rgba(30,111,255,0.3);
    }
    .nav-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 70px;
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 32px;
    }
    .logo {
      font-size: 1.8rem;
      font-weight: 700;
      letter-spacing: 1px;
      display: flex;
      align-items: center;
      gap: 10px;
      color: white;
      text-decoration: none;
    }
    .logo-icon {
      width: 34px;
      height: 34px;
      background: var(--electric-blue);
      border-radius: 8px;
      display: inline-block;
      position: relative;
      box-shadow: var(--shadow-glow-blue);
    }
    .nav-links {
      display: flex;
      gap: 35px;
      align-items: center;
      list-style: none;
    }
    .nav-links a {
      color: var(--text-secondary);
      text-decoration: none;
      font-weight: 500;
      font-size: 0.95rem;
      position: relative;
      padding: 8px 0;
    }
    .nav-links a::after {
      content: "";
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 3px;
      background: var(--accent-orange);
      transition: 0.25s;
      box-shadow: 0 0 12px var(--accent-orange);
    }
    .nav-links a:hover { color: white; }
    .nav-links a:hover::after { width: 100%; }
    .nav-cta {
      background: var(--electric-blue);
      padding: 10px 22px;
      border-radius: 30px;
      color: white !important;
      font-weight: 600;
      box-shadow: var(--shadow-glow-blue);
      transition: 0.3s;
    }
    .nav-cta:hover {
      box-shadow: var(--shadow-glow-hover);
      background: #3b82ff;
      transform: translateY(-2px);
    }
    .hamburger { display: none; background: none; border: none; color: white; font-size: 28px; }

    /* Hero */
    .hero-section {
      position: relative;
      padding: 100px 0 120px;
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
    }
    .hero-overlay {
      position: absolute; inset: 0; background: radial-gradient(circle at 20% 30%, rgba(10,14,39,0.6) 0%, #0A0E27 90%);
    }
    .hero-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      align-items: center;
      gap: 60px;
      position: relative;
      z-index: 2;
    }
    .hero-left h1 {
      font-size: 3.2rem;
      font-weight: 700;
      line-height: 1.2;
      margin-bottom: 20px;
    }
    .hero-sub {
      color: var(--text-secondary);
      font-size: 1.2rem;
      margin-bottom: 36px;
    }
    .btn-group { display: flex; gap: 18px; flex-wrap: wrap; }
    .btn-primary {
      background: var(--electric-blue);
      padding: 16px 38px;
      border-radius: 40px;
      font-weight: 700;
      color: white;
      text-decoration: none;
      box-shadow: var(--shadow-glow-blue);
      border: none;
      cursor: pointer;
      transition: 0.3s;
    }
    .btn-ghost {
      background: transparent;
      border: 1.5px solid var(--electric-blue);
      padding: 16px 38px;
      border-radius: 40px;
      font-weight: 700;
      color: white;
      text-decoration: none;
    }
    .btn-ghost:hover { background: var(--electric-blue); }
    .hero-right-panel {
      background: rgba(20,27,56,0.7);
      backdrop-filter: blur(20px);
      border: 1px solid var(--card-border);
      border-radius: 24px;
      padding: 32px;
    }
    .stat-dynamic { font-family: var(--font-mono); font-size: 2rem; color: var(--accent-orange); }

    /* 通用区块 */
    section {
      padding: 100px 0;
      position: relative;
      z-index: 3;
    }
    h2 {
      font-size: 2.5rem;
      font-weight: 700;
      margin-bottom: 52px;
      letter-spacing: 2px;
    }

    /* 服务卡片 */
    .cards-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }
    .service-card {
      background: var(--card-bg);
      backdrop-filter: blur(16px);
      border: 1px solid var(--card-border);
      border-radius: var(--radius-lg);
      padding: 36px 32px;
      transition: 0.3s;
    }
    .service-card.middle { border-top: 4px solid var(--accent-orange); transform: scale(1.03); }
    .service-card h3 { font-size: 1.5rem; margin: 16px 0 12px; }

    /* 优势数据 */
    .advantage-stats {
      display: grid;
      grid-template-columns: repeat(4,1fr);
      gap: 32px;
      background: rgba(18,24,42,0.7);
      padding: 48px;
      border-radius: var(--radius-lg);
    }
    .stat-item { text-align: center; }
    .stat-number { font-size: 3rem; font-weight: 700; color: var(--accent-orange); font-family: var(--font-mono); }

    /* 案例卡片 */
    .case-scroll {
      display: flex;
      gap: 28px;
      overflow-x: auto;
      padding-bottom: 15px;
    }
    .case-card {
      min-width: 300px;
      background: var(--card-bg);
      backdrop-filter: blur(16px);
      border-radius: var(--radius-lg);
      overflow: hidden;
      border: 1px solid rgba(255,255,255,0.08);
    }
    .case-img { height: 160px; background: url('/assets/images/coverpic/cover-2.webp') center/cover; }

    /* FAQ */
    .faq-item {
      background: rgba(20,27,56,0.5);
      backdrop-filter: blur(14px);
      border-radius: var(--radius-md);
      margin-bottom: 16px;
      padding: 22px 30px;
      border-left: 4px solid transparent;
      transition: 0.2s;
    }
    .faq-item.active { border-left-color: var(--accent-orange); background: rgba(20,27,56,0.75); }

    @media (max-width: 1024px) {
      .container { padding: 0 24px; }
      .hero-grid { grid-template-columns: 1fr; }
      .cards-grid { grid-template-columns: repeat(2,1fr); }
      .advantage-stats { grid-template-columns: repeat(2,1fr); }
    }
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .hamburger { display: block; }
      .cards-grid, .advantage-stats { grid-template-columns: 1fr; }
      h2 { font-size: 2rem; }
    }