/* roulang page: index */
:root {
      --primary-deep: #0A0E27;
      --accent-cyan: #00F0FF;
      --accent-magenta: #FF3CAC;
      --bg-light: #F5F5F7;
      --white: #FFFFFF;
      --gray-100: #F9FAFB;
      --gray-200: #E5E7EB;
      --gray-400: #9CA3AF;
      --gray-500: #6B7280;
      --gray-700: #374151;
      --text-main: #0A0E27;
      --shadow-sm: 0 1px 3px rgba(0,0,0,0.04), 0 1px 2px rgba(0,0,0,0.06);
      --shadow-hover: 0 10px 25px rgba(0,0,0,0.08), 0 4px 10px rgba(0,0,0,0.05);
      --border-radius-card: 12px;
      --border-radius-btn: 8px;
      --transition-base: 0.25s ease;
      --max-width: 1200px;
      --nav-height: 64px;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    body {
      font-family: 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', sans-serif;
      background-color: var(--white);
      color: var(--gray-700);
      line-height: 1.7;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }
    .container {
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 24px;
    }
    section {
      padding: 80px 0;
      scroll-margin-top: var(--nav-height);
    }
    h2 {
      font-size: 32px;
      font-weight: 600;
      line-height: 1.3;
      color: var(--text-main);
      margin-bottom: 16px;
      letter-spacing: -0.5px;
      text-align: center;
      position: relative;
    }
    h2::after {
      content: '';
      display: block;
      width: 48px;
      height: 3px;
      background: linear-gradient(90deg, var(--accent-cyan), var(--accent-magenta));
      margin: 12px auto 0;
      border-radius: 4px;
    }
    h3 {
      font-size: 22px;
      font-weight: 600;
      color: var(--text-main);
      margin-bottom: 8px;
      line-height: 1.4;
    }
    .section-subtitle {
      text-align: center;
      color: var(--gray-500);
      max-width: 600px;
      margin: 0 auto 48px;
      font-size: 16px;
    }
    /* 导航 */
    #nav {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: var(--nav-height);
      background: rgba(255,255,255,0.95);
      backdrop-filter: blur(10px);
      z-index: 100;
      box-shadow: 0 1px 6px rgba(0,0,0,0.02);
      transition: background 0.3s, box-shadow 0.3s;
      display: flex;
      align-items: center;
    }
    #nav.scrolled {
      background: rgba(255,255,255,1);
      box-shadow: 0 2px 12px rgba(0,0,0,0.06);
    }
    .nav-container {
      display: flex;
      justify-content: space-between;
      align-items: center;
      width: 100%;
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 24px;
    }
    .logo {
      font-size: 22px;
      font-weight: 700;
      color: var(--text-main);
      display: flex;
      align-items: center;
      gap: 6px;
      text-decoration: none;
    }
    .logo i {
      color: var(--accent-cyan);
      font-size: 24px;
    }
    .logo span {
      letter-spacing: -0.3px;
    }
    .nav-links {
      display: flex;
      gap: 32px;
      align-items: center;
    }
    .nav-links a {
      color: var(--gray-700);
      text-decoration: none;
      font-weight: 500;
      font-size: 15px;
      transition: color 0.2s;
      position: relative;
      padding-bottom: 4px;
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--accent-cyan);
      transition: width 0.2s;
    }
    .nav-links a:hover,
    .nav-links a.active {
      color: var(--accent-cyan);
    }
    .nav-links a:hover::after,
    .nav-links a.active::after {
      width: 100%;
    }
    .menu-toggle {
      display: none;
      font-size: 24px;
      background: none;
      border: none;
      color: var(--text-main);
      cursor: pointer;
    }
    /* Hero */
    #hero {
      background-color: var(--primary-deep);
      background-image: 
        linear-gradient(rgba(10,14,39,0.92), rgba(10,14,39,0.96)),
        url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      min-height: 90vh;
      display: flex;
      align-items: center;
      color: white;
      padding: 120px 0 80px;
      position: relative;
    }
    .hero-grid {
      display: grid;
      grid-template-columns: 1.1fr 0.9fr;
      gap: 48px;
      align-items: center;
    }
    .hero-content h1 {
      font-size: 52px;
      font-weight: 700;
      line-height: 1.2;
      background: linear-gradient(90deg, var(--accent-cyan), var(--accent-magenta));
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
      margin-bottom: 20px;
      letter-spacing: -0.8px;
    }
    .hero-content .subtitle {
      font-size: 18px;
      color: var(--gray-400);
      margin-bottom: 32px;
    }
    .btn-group {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
      align-items: center;
    }
    .btn-primary {
      background: var(--accent-cyan);
      color: var(--primary-deep);
      font-weight: 600;
      padding: 14px 32px;
      border-radius: var(--border-radius-btn);
      border: none;
      cursor: pointer;
      font-size: 16px;
      transition: background 0.2s, transform 0.2s;
      text-decoration: none;
      display: inline-block;
    }
    .btn-primary:hover {
      background: #00D4E0;
      transform: scale(1.02);
      color: var(--primary-deep);
    }
    .btn-outline {
      background: transparent;
      border: 1.5px solid white;
      color: white;
      padding: 14px 28px;
      border-radius: var(--border-radius-btn);
      font-weight: 500;
      text-decoration: none;
      transition: 0.2s;
    }
    .btn-outline:hover {
      background: white;
      color: var(--primary-deep);
    }
    .hero-image img {
      width: 100%;
      border-radius: 16px;
      box-shadow: 0 20px 40px rgba(0,0,0,0.5);
    }
    /* 数据看板 */
    #dashboard {
      background: var(--bg-light);
    }
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .stat-card {
      background: var(--primary-deep);
      border-radius: var(--border-radius-card);
      padding: 28px 20px;
      text-align: center;
      color: white;
      transition: transform 0.25s, box-shadow 0.25s;
    }
    .stat-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
    }
    .stat-number {
      font-family: 'DIN Alternate', 'SF Mono', monospace;
      font-size: 44px;
      font-weight: 700;
      color: var(--accent-cyan);
      margin-bottom: 8px;
    }
    .stat-label {
      font-size: 16px;
      color: var(--gray-400);
    }
    /* 服务体系 */
    #services {
      background: white;
    }
    .services-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
    }
    .service-card {
      background: white;
      border: 1px solid var(--gray-200);
      border-radius: var(--border-radius-card);
      padding: 28px 20px;
      box-shadow: var(--shadow-sm);
      transition: all 0.25s;
      display: flex;
      flex-direction: column;
    }
    .service-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
      border-color: var(--accent-cyan);
    }
    .service-icon {
      width: 64px;
      height: 64px;
      margin-bottom: 20px;
      border-radius: 12px;
      overflow: hidden;
      background: var(--bg-light);
      display: flex;
      align-items: center;
      justify-content: center;
    }
    .service-icon img {
      width: 100%;
      height: 100%;
      object-fit: cover;
    }
    .service-card h3 {
      font-size: 20px;
      margin-bottom: 8px;
    }
    .service-card p {
      color: var(--gray-500);
      font-size: 15px;
    }
    /* 战绩对比 */
    #comparison {
      background: var(--bg-light);
    }
    .comparison-table {
      background: white;
      border-radius: 16px;
      overflow: hidden;
      box-shadow: var(--shadow-sm);
    }
    .table-row {
      display: grid;
      grid-template-columns: 1.5fr 2fr 2fr;
      padding: 16px 24px;
      align-items: center;
      border-bottom: 1px solid var(--gray-200);
    }
    .table-row.header {
      background: var(--primary-deep);
      color: white;
      font-weight: 600;
      border-bottom: none;
    }
    .table-row:nth-child(even):not(.header) {
      background: var(--gray-100);
    }
    .mk-highlight {
      color: var(--accent-cyan);
      font-weight: 700;
    }
    .competitor {
      color: var(--gray-500);
    }
    /* FAQ */
    #faq {
      background: white;
    }
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
    }
    .faq-item {
      border-bottom: 1px solid var(--gray-200);
    }
    .faq-question {
      width: 100%;
      background: none;
      border: none;
      padding: 20px 8px;
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-weight: 600;
      font-size: 17px;
      color: var(--text-main);
      cursor: pointer;
      transition: color 0.2s;
    }
    .faq-question i {
      transition: 0.3s;
      color: var(--accent-magenta);
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      padding: 0 8px;
    }
    .faq-answer p {
      padding-bottom: 20px;
      color: var(--gray-700);
    }
    .faq-item.active .faq-question {
      color: var(--accent-cyan);
    }
    .faq-item.active .faq-question i {
      transform: rotate(180deg);
      color: var(--accent-cyan);
    }
    /* CTA */
    #cta {
      background: var(--primary-deep);
      color: white;
    }
    .cta-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 40px;
      align-items: center;
    }
    .cta-form input, .cta-form textarea {
      width: 100%;
      padding: 14px;
      margin-bottom: 16px;
      border-radius: 6px;
      border: 1px solid var(--gray-200);
      font-family: inherit;
      background: white;
      transition: 0.2s;
    }
    .cta-form input:focus, .cta-form textarea:focus {
      outline: none;
      border-color: var(--accent-cyan);
      box-shadow: 0 0 0 3px rgba(0,240,255,0.2);
    }
    .cta-image img {
      width: 100%;
      border-radius: 20px;
    }
    .trust-text {
      font-size: 14px;
      color: var(--gray-400);
      margin-top: 12px;
    }
    /* footer */
    #footer {
      background: var(--primary-deep);
      color: var(--gray-400);
      padding: 48px 0 24px;
    }
    .footer-grid {
      display: flex;
      justify-content: space-between;
      flex-wrap: wrap;
      gap: 32px;
    }
    .footer-links a {
      color: var(--gray-400);
      text-decoration: none;
      margin-right: 20px;
    }
    .back-top {
      background: var(--accent-cyan);
      width: 44px;
      height: 44px;
      border-radius: 50%;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      color: var(--primary-deep);
      font-size: 20px;
    }
    @media (max-width: 1024px) {
      .services-grid { grid-template-columns: repeat(2,1fr); }
      .stats-grid { grid-template-columns: repeat(2,1fr); }
    }
    @media (max-width: 768px) {
      .menu-toggle { display: block; }
      .nav-links {
        position: fixed; top: 64px; left: 0; background: white;
        width: 100%; flex-direction: column; gap: 24px; padding: 32px;
        transform: translateY(-120%); transition: 0.3s; box-shadow: 0 10px 20px rgba(0,0,0,0.05);
      }
      .nav-links.open { transform: translateY(0); }
      .hero-grid { grid-template-columns: 1fr; }
      .hero-content h1 { font-size: 36px; }
      .stats-grid, .services-grid { grid-template-columns: 1fr; }
      .table-row { grid-template-columns: 1fr; gap: 8px; }
      .cta-grid { grid-template-columns: 1fr; }
    }
    .fade-up { opacity: 0; transform: translateY(20px); transition: 0.6s; }
    .fade-up.visible { opacity: 1; transform: translateY(0); }