/* roulang page: index */
:root {
      --deep-cyan: #0B3B42;
      --ice-white: #E6F0F2;
      --aurora-green: #2ED9A3;
      --bg-deep: #0A1A1F;
      --card-glass-bg: rgba(11, 59, 66, 0.45);
      --card-border: rgba(46, 217, 163, 0.18);
      --text-primary: #E6F0F2;
      --text-secondary: #9DB5B8;
      --shadow-glow: 0 20px 40px rgba(0,0,0,0.5);
      --button-glow: 0 0 18px rgba(46,217,163,0.6);
      --border-radius-card: 24px;
      --border-radius-btn: 40px;
      --font-mono: 'Inter', 'SF Mono', monospace;
      --font-sans: 'PingFang SC', 'Microsoft YaHei', 'Inter', sans-serif;
      --transition-fast: 0.25s ease;
      --container-max: 1320px;
      --gutter: 24px;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    html {
      scroll-behavior: smooth;
      font-size: 16px;
    }
    body {
      background-color: var(--bg-deep);
      color: var(--text-primary);
      font-family: var(--font-sans);
      line-height: 1.7;
      -webkit-font-smoothing: antialiased;
      overflow-x: hidden;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: color var(--transition-fast);
    }
    button, input, textarea {
      font-family: inherit;
      outline: none;
    }
    .container {
      width: 100%;
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 24px;
    }
    /* 导航 */
    .header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      background: rgba(10, 26, 31, 0.78);
      backdrop-filter: blur(20px);
      border-bottom: 1px solid rgba(46, 217, 163, 0.2);
      transition: background var(--transition-fast);
    }
    .nav {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 72px;
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 24px;
    }
    .logo {
      display: flex;
      align-items: center;
      gap: 12px;
      font-weight: 700;
      font-size: 1.5rem;
      letter-spacing: -0.3px;
      color: var(--ice-white);
    }
    .logo-icon {
      width: 24px;
      height: 24px;
      background: var(--aurora-green);
      transform: rotate(45deg);
      border-radius: 4px;
      box-shadow: 0 0 12px rgba(46,217,163,0.6);
    }
    .nav-links {
      display: flex;
      gap: 36px;
      align-items: center;
      list-style: none;
    }
    .nav-links a {
      color: var(--text-secondary);
      font-weight: 500;
      font-size: 0.95rem;
      position: relative;
      padding: 6px 0;
      transition: color var(--transition-fast);
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--aurora-green);
      transition: width var(--transition-fast);
    }
    .nav-links a:hover, .nav-links a.active {
      color: var(--aurora-green);
    }
    .nav-links a:hover::after, .nav-links a.active::after {
      width: 100%;
    }
    .hamburger {
      display: none;
      flex-direction: column;
      justify-content: space-between;
      width: 24px;
      height: 18px;
      background: none;
      border: none;
      cursor: pointer;
      padding: 0;
    }
    .hamburger span {
      display: block;
      width: 100%;
      height: 2px;
      background: var(--ice-white);
      transition: all var(--transition-fast);
    }
    .mobile-menu {
      display: none;
      position: fixed;
      top: 72px;
      left: 0;
      width: 100%;
      background: rgba(10, 26, 31, 0.95);
      backdrop-filter: blur(20px);
      flex-direction: column;
      align-items: center;
      gap: 36px;
      padding: 48px 24px;
      z-index: 999;
    }
    .mobile-menu a {
      font-size: 1.6rem;
      color: var(--ice-white);
      font-weight: 500;
    }
    /* 区块通用 */
    section {
      padding: 100px 0;
      position: relative;
    }
    .section-title {
      font-size: 2.25rem;
      font-weight: 600;
      letter-spacing: -0.3px;
      margin-bottom: 16px;
      color: var(--ice-white);
    }
    .section-sub {
      color: var(--text-secondary);
      font-size: 1.1rem;
      margin-bottom: 48px;
      max-width: 680px;
    }
    /* 玻璃卡片 */
    .glass-card {
      background: var(--card-glass-bg);
      backdrop-filter: blur(18px);
      border: 1px solid var(--card-border);
      border-radius: var(--border-radius-card);
      box-shadow: var(--shadow-glow);
      transition: border var(--transition-fast), background var(--transition-fast);
    }
    .glass-card:hover {
      border-color: rgba(46, 217, 163, 0.45);
      background: rgba(11, 59, 66, 0.55);
    }
    /* 按钮 */
    .btn-glow {
      background: var(--aurora-green);
      color: #0A1A1F;
      font-weight: 600;
      padding: 14px 32px;
      border-radius: var(--border-radius-btn);
      border: none;
      cursor: pointer;
      box-shadow: var(--button-glow);
      transition: all var(--transition-fast);
      display: inline-block;
      text-align: center;
      letter-spacing: -0.2px;
    }
    .btn-glow:hover {
      box-shadow: 0 0 30px rgba(46,217,163,0.8);
      background: #5EE8B8;
    }
    .btn-ghost {
      background: transparent;
      border: 1px solid var(--aurora-green);
      color: var(--aurora-green);
      padding: 12px 28px;
      border-radius: var(--border-radius-btn);
      font-weight: 500;
      transition: all var(--transition-fast);
      display: inline-block;
    }
    .btn-ghost:hover {
      background: rgba(46,217,163,0.1);
      border-color: #5EE8B8;
      color: #5EE8B8;
    }
    /* 数据看板 */
    .dashboard-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
    }
    .metric-card {
      text-align: center;
      padding: 32px 16px;
    }
    .metric-number {
      font-family: var(--font-mono);
      font-size: 3.5rem;
      font-weight: 700;
      color: var(--aurora-green);
      text-shadow: 0 0 12px rgba(46,217,163,0.4);
      animation: breathe 3s infinite ease-in-out;
    }
    @keyframes breathe {
      0% { text-shadow: 0 0 8px rgba(46,217,163,0.3); }
      50% { text-shadow: 0 0 18px rgba(46,217,163,0.7); }
      100% { text-shadow: 0 0 8px rgba(46,217,163,0.3); }
    }
    .metric-label {
      color: var(--text-secondary);
      font-size: 0.9rem;
      margin-top: 8px;
      letter-spacing: 0.4px;
    }
    /* 服务矩阵 */
    .services-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
      gap: 24px;
    }
    .service-card {
      padding: 32px;
      display: flex;
      flex-direction: column;
    }
    .service-icon {
      font-size: 2rem;
      color: var(--aurora-green);
      margin-bottom: 20px;
      opacity: 0.8;
    }
    .service-card h3 {
      font-size: 1.4rem;
      font-weight: 500;
      margin-bottom: 12px;
    }
    .service-desc {
      color: var(--text-secondary);
      margin-bottom: 24px;
      flex: 1;
    }
    .service-link {
      color: var(--aurora-green);
      font-weight: 500;
      display: inline-flex;
      align-items: center;
      gap: 6px;
      transition: gap var(--transition-fast);
      align-self: flex-start;
    }
    .service-link:hover {
      gap: 12px;
    }
    /* 对比区块 */
    .compare-row {
      display: flex;
      gap: 40px;
      align-items: center;
      flex-wrap: wrap;
    }
    .compare-col {
      flex: 1 1 300px;
      background: rgba(11,59,66,0.35);
      border-radius: 24px;
      padding: 32px;
      border: 1px solid rgba(255,255,255,0.05);
    }
    .compare-col.highlight {
      border-color: var(--aurora-green);
      box-shadow: 0 0 24px rgba(46,217,163,0.2);
    }
    .compare-item {
      display: flex;
      align-items: center;
      justify-content: space-between;
      margin: 20px 0;
    }
    .progress-bar {
      width: 60%;
      height: 4px;
      background: rgba(255,255,255,0.1);
      border-radius: 4px;
      overflow: hidden;
    }
    .progress-fill {
      height: 100%;
      background: var(--aurora-green);
      width: 0%;
      box-shadow: 0 0 8px var(--aurora-green);
    }
    .vs-badge {
      font-weight: 700;
      font-size: 1.4rem;
      color: var(--aurora-green);
      text-align: center;
      padding: 0 20px;
    }
    /* FAQ */
    .faq-list {
      display: flex;
      flex-direction: column;
      gap: 16px;
    }
    .faq-item {
      background: rgba(11,59,66,0.35);
      border-radius: 20px;
      overflow: hidden;
      border: 1px solid transparent;
      transition: border var(--transition-fast);
    }
    .faq-item.active {
      border-left: 3px solid var(--aurora-green);
      background: rgba(11,59,66,0.5);
    }
    .faq-question {
      padding: 24px 28px;
      font-weight: 500;
      cursor: pointer;
      display: flex;
      align-items: center;
      gap: 12px;
    }
    .faq-icon {
      color: var(--aurora-green);
      font-size: 1.2rem;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      background: rgba(0,0,0,0.25);
      padding: 0 28px;
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding: 20px 28px;
    }
    /* CTA 表单 */
    .cta-form {
      display: flex;
      flex-wrap: wrap;
      gap: 20px;
      align-items: flex-end;
      justify-content: space-between;
    }
    .form-group {
      flex: 1 1 220px;
    }
    .form-input {
      width: 100%;
      background: rgba(11,59,66,0.4);
      border: 1px solid rgba(46,217,163,0.25);
      border-radius: 40px;
      padding: 14px 20px;
      color: white;
      transition: border var(--transition-fast), box-shadow var(--transition-fast);
    }
    .form-input:focus {
      border-color: var(--aurora-green);
      box-shadow: 0 0 14px rgba(46,217,163,0.4);
    }
    .privacy-note {
      font-size: 0.8rem;
      color: var(--text-secondary);
      margin-top: 20px;
    }
    /* 页脚 */
    .footer-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 40px;
      margin-bottom: 48px;
    }
    .footer-col h4 {
      color: var(--ice-white);
      margin-bottom: 20px;
      font-weight: 600;
    }
    .footer-col a {
      display: block;
      color: var(--text-secondary);
      margin-bottom: 12px;
      transition: color var(--transition-fast);
    }
    .footer-col a:hover {
      color: var(--aurora-green);
    }
    .back-to-top {
      position: fixed;
      bottom: 32px;
      right: 32px;
      width: 48px;
      height: 48px;
      border-radius: 50%;
      background: var(--aurora-green);
      box-shadow: 0 0 18px rgba(46,217,163,0.7);
      display: flex;
      align-items: center;
      justify-content: center;
      color: #0A1A1F;
      font-size: 1.4rem;
      z-index: 800;
      transition: 0.2s;
      border: none;
      cursor: pointer;
    }
    .back-to-top:hover {
      background: #5EE8B8;
    }
    /* 响应式 */
    @media (max-width: 1024px) {
      .dashboard-grid { grid-template-columns: repeat(2,1fr); }
    }
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .hamburger { display: flex; }
      .mobile-menu.open { display: flex; }
      .dashboard-grid { grid-template-columns: 1fr; }
      .metric-number { font-size: 2.5rem; }
      h1 { font-size: 2rem !important; }
      .compare-row { flex-direction: column; }
      .footer-grid { grid-template-columns: 1fr 1fr; }
    }
    @media (max-width: 520px) {
      .footer-grid { grid-template-columns: 1fr; }
      .cta-form { flex-direction: column; }
    }