/* roulang page: index */
/* 设计系统变量 & 基础重置 */
    :root {
      --deep-space: #0B0E14;
      --live-red: #E6332D;
      --neon-cyan: #00F0C8;
      --warm-white: #F4F4F5;
      --text-secondary: #B0B3C1;
      --card-bg: rgba(26, 29, 38, 0.7);
      --glass-border: rgba(255, 255, 255, 0.06);
      --shadow-card: 0 8px 32px rgba(0, 0, 0, 0.4);
      --radius-card: 16px;
      --radius-pill: 50px;
      --font-sans: 'Inter', 'PingFang SC', 'Microsoft YaHei', 'Noto Sans SC', system-ui, -apple-system, sans-serif;
      
      --h1-size: 42px;
      --h1-weight: 700;
      --h1-letter-spacing: -0.5px;
      --h2-size: 32px;
      --h2-weight: 700;
      --h3-size: 20px;
      --h3-weight: 600;
      --body-size: 16px;
      --body-line-height: 1.75;
      
      --container-max: 1280px;
      --grid-gap: 24px;
      --nav-height: 72px;
    }
    
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    
    html {
      scroll-behavior: smooth;
      background-color: var(--deep-space);
    }
    
    body {
      font-family: var(--font-sans);
      font-size: var(--body-size);
      line-height: var(--body-line-height);
      color: var(--warm-white);
      background: var(--deep-space);
      background-image: 
        linear-gradient(rgba(255,255,255,0.02) 1px, transparent 1px),
        linear-gradient(90deg, rgba(255,255,255,0.02) 1px, transparent 1px);
      background-size: 40px 40px;
      -webkit-font-smoothing: antialiased;
      overflow-x: hidden;
    }
    
    .container {
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 24px;
      width: 100%;
    }
    
    a, button, input, textarea {
      font-family: var(--font-sans);
      text-decoration: none;
      border: none;
      outline: none;
      transition: all 0.3s ease;
    }
    
    img {
      max-width: 100%;
      display: block;
      height: auto;
    }
    
    h1, h2, h3 {
      letter-spacing: -0.3px;
    }
    
    /* 栅格工具 */
    .grid {
      display: grid;
      gap: var(--grid-gap);
    }
    
    .grid-4 {
      grid-template-columns: repeat(4, 1fr);
    }
    .grid-3 {
      grid-template-columns: repeat(3, 1fr);
    }
    .grid-2 {
      grid-template-columns: repeat(2, 1fr);
    }
    
    /* ══════════ 导航 ══════════ */
    header {
      position: sticky;
      top: 0;
      z-index: 100;
      background: rgba(11, 14, 20, 0.9);
      backdrop-filter: blur(16px);
      -webkit-backdrop-filter: blur(16px);
      border-bottom: 1px solid rgba(0, 240, 200, 0.25);
      height: var(--nav-height);
      display: flex;
      align-items: center;
    }
    
    .nav-bar {
      display: flex;
      justify-content: space-between;
      align-items: center;
      width: 100%;
    }
    
    .logo {
      display: flex;
      align-items: center;
      gap: 10px;
    }
    .logo-text {
      font-size: 24px;
      font-weight: 800;
      color: var(--warm-white);
      letter-spacing: -0.2px;
    }
    .logo-icon {
      color: var(--neon-cyan);
      font-size: 28px;
    }
    .logo-icon i {
      filter: drop-shadow(0 0 6px var(--neon-cyan));
    }
    
    .nav-links {
      display: flex;
      align-items: center;
      gap: 32px;
    }
    
    .nav-links a {
      font-size: 16px;
      font-weight: 500;
      color: var(--text-secondary);
      position: relative;
    }
    .nav-links a:hover {
      color: var(--neon-cyan);
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: -6px;
      left: 0;
      width: 0%;
      height: 2px;
      background: var(--neon-cyan);
      transition: width 0.3s ease;
    }
    .nav-links a:hover::after {
      width: 100%;
    }
    
    .btn-nav-cta {
      background: var(--live-red);
      color: white;
      padding: 10px 24px;
      border-radius: var(--radius-pill);
      font-weight: 600;
      font-size: 15px;
      margin-left: 12px;
      box-shadow: 0 4px 12px rgba(230, 51, 45, 0.3);
    }
    .btn-nav-cta:hover {
      box-shadow: 0 0 20px rgba(230,51,45,0.65);
      transform: scale(1.05);
    }
    
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 6px;
      cursor: pointer;
    }
    .hamburger span {
      width: 28px;
      height: 3px;
      background: var(--warm-white);
      border-radius: 4px;
      transition: 0.3s;
    }
    
    /* ══════════ 板块间距 ══════════ */
    section {
      padding: 90px 0;
      position: relative;
    }
    
    /* ══════════ Hero ══════════ */
    .hero-content {
      display: flex;
      align-items: center;
      gap: 60px;
    }
    .hero-text {
      flex: 1;
    }
    .hero-text h1 {
      font-size: var(--h1-size);
      font-weight: var(--h1-weight);
      letter-spacing: var(--h1-letter-spacing);
      line-height: 1.3;
      margin-bottom: 18px;
      color: white;
    }
    .hero-sub {
      font-size: 18px;
      color: var(--text-secondary);
      margin-bottom: 30px;
    }
    .btn-group {
      display: flex;
      flex-wrap: wrap;
      gap: 16px;
    }
    .btn-primary {
      background: var(--live-red);
      color: white;
      padding: 14px 36px;
      border-radius: var(--radius-pill);
      font-weight: 600;
      box-shadow: 0 4px 16px rgba(230,51,45,0.4);
      display: inline-flex;
      align-items: center;
      gap: 8px;
    }
    .btn-primary:hover {
      box-shadow: 0 0 28px rgba(230,51,45,0.75);
      transform: translateY(-2px);
    }
    .btn-secondary {
      background: transparent;
      border: 2px solid var(--neon-cyan);
      color: var(--neon-cyan);
      padding: 14px 36px;
      border-radius: var(--radius-pill);
      font-weight: 600;
    }
    .btn-secondary:hover {
      background: rgba(0,240,200,0.08);
      box-shadow: 0 0 18px rgba(0,240,200,0.4);
      transform: translateY(-2px);
    }
    
    .hero-visual {
      flex: 1;
      background: rgba(26,29,38,0.55);
      backdrop-filter: blur(20px);
      border-radius: 24px;
      padding: 20px;
      border: 1px solid var(--glass-border);
      position: relative;
    }
    .live-badge {
      position: absolute;
      top: 20px;
      left: 20px;
      background: var(--live-red);
      color: white;
      font-weight: 700;
      font-size: 14px;
      padding: 4px 14px;
      border-radius: 20px;
      letter-spacing: 0.6px;
      display: flex;
      align-items: center;
      gap: 6px;
      animation: pulse-badge 1.8s infinite;
    }
    @keyframes pulse-badge {
      0% { box-shadow: 0 0 8px var(--live-red); }
      50% { box-shadow: 0 0 22px var(--live-red), 0 0 35px var(--live-red); }
      100% { box-shadow: 0 0 8px var(--live-red); }
    }
    
    /* ═══════ Section Headings ═══════ */
    .section-title {
      font-size: var(--h2-size);
      font-weight: var(--h2-weight);
      margin-bottom: 50px;
      text-align: center;
    }
    .card {
      background: var(--card-bg);
      backdrop-filter: blur(20px);
      border-radius: var(--radius-card);
      border: 1px solid var(--glass-border);
      box-shadow: var(--shadow-card);
      padding: 32px 24px;
      transition: all 0.3s ease;
    }
    .card:hover {
      transform: translateY(-6px);
      border-color: var(--neon-cyan);
      box-shadow: 0 16px 40px rgba(0,240,200,0.1);
    }
    
    /* ═══════ 服务矩阵卡片图像 ═══════ */
    .service-card-img {
      height: 200px;
      background-size: cover;
      background-position: center;
      border-radius: 12px;
      margin-bottom: 20px;
      position: relative;
      overflow: hidden;
      transition: transform 0.4s;
    }
    .card:hover .service-card-img {
      transform: scale(1.04);
    }
    
    /* ═══════ 数据看板 ═══════ */
    .dashboard-grid {
      display: flex;
      flex-wrap: wrap;
      gap: 28px;
      justify-content: center;
    }
    .data-card {
      background: rgba(20,24,38,0.8);
      backdrop-filter: blur(18px);
      padding: 30px 24px;
      border-radius: 20px;
      text-align: center;
      flex: 1 1 200px;
      border: 1px solid rgba(0,240,200,0.15);
    }
    .data-number {
      font-size: 48px;
      font-weight: 800;
      color: var(--neon-cyan);
      line-height: 1.2;
    }
    
    /* ═══════ 解决方案插图 ═══════ */
    .solution-row {
      display: flex;
      align-items: center;
      gap: 50px;
      margin-bottom: 80px;
    }
    .solution-img {
      flex: 1;
      background-size: cover;
      background-position: center;
      height: 280px;
      border-radius: 20px;
    }
    
    /* 表单 */
    input, textarea {
      background: #1a1d26;
      border: 1px solid rgba(255,255,255,0.08);
      border-radius: 14px;
      padding: 14px 18px;
      width: 100%;
      color: white;
      margin-bottom: 16px;
      font-size: 16px;
    }
    input:focus, textarea:focus {
      border-color: var(--neon-cyan);
      box-shadow: 0 0 14px rgba(0,240,200,0.3);
    }
    .btn-form {
      width: 100%;
      background: var(--live-red);
      color: white;
      padding: 16px;
      border-radius: 50px;
      font-weight: 700;
    }
    
    /* FAQ */
    details {
      background: rgba(26,29,38,0.7);
      backdrop-filter: blur(16px);
      border-radius: 14px;
      padding: 20px 28px;
      margin-bottom: 16px;
      border: 1px solid var(--glass-border);
      cursor: pointer;
    }
    summary {
      font-weight: 600;
      font-size: 18px;
      display: flex;
      justify-content: space-between;
    }
    
    /* 浮空按钮 */
    .floating-cta {
      position: fixed;
      bottom: 32px;
      right: 32px;
      width: 56px;
      height: 56px;
      background: var(--live-red);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      box-shadow: 0 0 24px rgba(230,51,45,0.7);
      animation: float-pulse 2s infinite;
      z-index: 200;
      color: white;
      font-size: 22px;
    }
    @keyframes float-pulse {
      0% { transform: scale(1); }
      50% { transform: scale(1.12); }
      100% { transform: scale(1); }
    }
    
    footer {
      background: #070a10;
      padding: 60px 0 30px;
    }
    
    /* 移动端 */
    @media (max-width: 768px) {
      .hamburger { display: flex; }
      .nav-links { display: none; position: fixed; top: 72px; left:0; width:100%; background: rgba(11,14,20,0.97); flex-direction: column; padding: 32px; gap: 24px; backdrop-filter: blur(24px); }
      .nav-links.active { display: flex; }
      .hero-content { flex-direction: column; }
      .grid-4, .grid-3 { grid-template-columns: repeat(2,1fr); }
      .solution-row { flex-direction: column; }
    }
    @media (max-width: 520px) {
      .grid-4, .grid-3 { grid-template-columns: 1fr; }
    }