/* roulang page: index */
:root {
      --primary: #1A5F7A;
      --secondary: #0D9488;
      --bg-light: #F8FAFC;
      --bg-white: #FFFFFF;
      --bg-alt: #F1F5F9;
      --text-dark: #0F172A;
      --text-muted: #475569;
      --accent: #F59E0B;
      --accent-hover: #D97706;
      --border: #E2E8F0;
      --border-focus: #1A5F7A;
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-tag: 8px;
      --shadow-sm: 0 1px 3px rgba(0,0,0,0.06), 0 4px 12px rgba(0,0,0,0.04);
      --shadow-hover: 0 8px 24px rgba(0,0,0,0.08);
      --font-sans: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", system-ui, -apple-system, sans-serif;
      --font-number: "Inter", "SF Pro Text", system-ui, -apple-system, sans-serif;
      --spacing-section: 90px;
      --max-width: 1200px;
    }
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }
    body {
      font-family: var(--font-sans);
      background: var(--bg-light);
      color: var(--text-dark);
      line-height: 1.6;
      -webkit-font-smoothing: antialiased;
      padding-top: 70px;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: color 0.2s ease;
    }
    button, .btn {
      cursor: pointer;
      font-family: inherit;
      transition: all 0.25s ease;
    }
    h1, h2, h3, h4 {
      font-weight: 600;
      line-height: 1.3;
    }
    .container {
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 24px;
    }
    /* 导航栏 */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      background: rgba(255,255,255,0.92);
      backdrop-filter: blur(12px);
      box-shadow: 0 1px 0 var(--border);
      z-index: 100;
      height: 70px;
      display: flex;
      align-items: center;
    }
    .header-inner {
      display: flex;
      justify-content: space-between;
      align-items: center;
      width: 100%;
    }
    .logo {
      font-size: 24px;
      font-weight: 700;
      color: var(--primary);
      letter-spacing: -0.3px;
      white-space: nowrap;
    }
    .logo small {
      font-size: 13px;
      font-weight: 400;
      color: var(--text-muted);
      margin-left: 6px;
      display: inline-block;
    }
    .nav-links {
      display: flex;
      gap: 32px;
      align-items: center;
    }
    .nav-links a {
      font-weight: 500;
      color: var(--text-muted);
      font-size: 15px;
      position: relative;
      padding: 4px 0;
    }
    .nav-links a:hover,
    .nav-links a.active {
      color: var(--primary);
    }
    .nav-links a.active::after {
      content: '';
      position: absolute;
      bottom: -4px;
      left: 0;
      width: 100%;
      height: 2px;
      background: var(--primary);
      border-radius: 2px;
    }
    .nav-cta {
      display: flex;
      align-items: center;
      gap: 10px;
    }
    .btn-cta {
      background: var(--accent);
      color: white;
      border: none;
      padding: 12px 26px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 15px;
      background: var(--accent);
      box-shadow: 0 2px 8px rgba(245,158,11,0.25);
      letter-spacing: 0.3px;
    }
    .btn-cta:hover {
      background: var(--accent-hover);
      box-shadow: 0 6px 16px rgba(217,119,6,0.3);
      transform: translateY(-1px);
    }
    .hot-badge {
      background: #DC2626;
      color: white;
      font-size: 12px;
      font-weight: 700;
      padding: 4px 8px;
      border-radius: 20px;
      margin-left: -8px;
    }
    .menu-toggle {
      display: none;
      background: none;
      border: none;
      font-size: 26px;
      color: var(--primary);
    }
    /* Hero */
    .hero {
      background: linear-gradient(135deg, #F8FAFC 0%, #E0F2F1 100%);
      padding: 70px 0 80px;
      min-height: 85vh;
      display: flex;
      align-items: center;
    }
    .hero-grid {
      display: flex;
      flex-wrap: wrap;
      align-items: center;
      gap: 48px;
    }
    .hero-left {
      flex: 1 1 500px;
    }
    .hero-right {
      flex: 1 1 400px;
      position: relative;
    }
    .hero h1 {
      font-size: 42px;
      font-weight: 700;
      letter-spacing: -0.5px;
      color: var(--text-dark);
      margin-bottom: 20px;
      line-height: 1.2;
    }
    .hero-sub {
      font-size: 18px;
      color: var(--text-muted);
      margin-bottom: 32px;
      max-width: 550px;
    }
    .micro-cards {
      display: flex;
      gap: 20px;
      margin-bottom: 32px;
      flex-wrap: wrap;
    }
    .micro-card {
      background: white;
      border-radius: 12px;
      padding: 16px 24px;
      box-shadow: var(--shadow-sm);
      display: flex;
      flex-direction: column;
      align-items: flex-start;
    }
    .micro-number {
      font-family: var(--font-number);
      font-size: 32px;
      font-weight: 700;
      color: var(--secondary);
    }
    .micro-label {
      color: var(--text-muted);
      font-size: 14px;
    }
    .btn-group {
      display: flex;
      gap: 16px;
      align-items: center;
      flex-wrap: wrap;
    }
    .btn-outline {
      background: transparent;
      border: 2px solid var(--primary);
      color: var(--primary);
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      font-weight: 600;
    }
    .btn-outline:hover {
      background: var(--primary);
      color: white;
    }
    .dashboard-mock {
      background: white;
      border-radius: 24px;
      padding: 20px;
      box-shadow: var(--shadow-hover);
      display: flex;
      flex-direction: column;
      gap: 16px;
    }
    .mock-chart {
      display: flex;
      gap: 12px;
      align-items: flex-end;
    }
    .bar {
      width: 28px;
      background: var(--secondary);
      border-radius: 6px 6px 0 0;
      opacity: 0.8;
    }
    .ring-placeholder {
      width: 80px;
      height: 80px;
      border: 8px solid #E2E8F0;
      border-top-color: var(--secondary);
      border-radius: 50%;
      margin: 10px auto;
    }
    /* 通用板块 */
    .section {
      padding: var(--spacing-section) 0;
    }
    .section h2 {
      font-size: 32px;
      font-weight: 600;
      margin-bottom: 16px;
      color: var(--text-dark);
      letter-spacing: -0.3px;
    }
    .section-sub {
      color: var(--text-muted);
      font-size: 17px;
      margin-bottom: 48px;
    }
    /* 卡片网格 */
    .card-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
      gap: 28px;
    }
    .card {
      background: white;
      border-radius: var(--radius-card);
      padding: 28px 24px;
      box-shadow: var(--shadow-sm);
      border: 1px solid var(--border);
      transition: all 0.25s;
      display: flex;
      flex-direction: column;
    }
    .card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-hover);
    }
    .card-icon {
      font-size: 40px;
      color: var(--secondary);
      margin-bottom: 18px;
    }
    .card h3 {
      font-size: 22px;
      margin-bottom: 12px;
    }
    .card p {
      color: var(--text-muted);
      font-size: 15px;
      line-height: 1.7;
      flex: 1;
      margin-bottom: 18px;
    }
    .metric {
      font-family: var(--font-number);
      font-weight: 700;
      font-size: 28px;
      color: var(--secondary);
    }
    /* 对比区 */
    .compare-panel {
      display: flex;
      flex-wrap: wrap;
      gap: 30px;
      background: white;
      border-radius: 20px;
      padding: 40px;
      box-shadow: var(--shadow-sm);
    }
    .compare-col {
      flex: 1;
      min-width: 220px;
    }
    .before-bg {
      background: #FEF2F2;
      padding: 24px;
      border-radius: 16px;
    }
    .after-bg {
      background: #ECFDF5;
      padding: 24px;
      border-radius: 16px;
    }
    .compare-item {
      display: flex;
      justify-content: space-between;
      margin: 18px 0;
    }
    .bar-visual {
      height: 8px;
      background: #CBD5E1;
      border-radius: 4px;
      width: 100%;
      margin: 4px 0;
    }
    .bar-fill {
      height: 8px;
      background: var(--secondary);
      border-radius: 4px;
    }
    /* 数据看板 */
    .metric-scroll {
      display: flex;
      gap: 24px;
      overflow-x: auto;
      padding: 12px 0 24px;
      scroll-snap-type: x mandatory;
    }
    .metric-card {
      flex: 0 0 200px;
      background: white;
      border-radius: 16px;
      padding: 24px;
      box-shadow: var(--shadow-sm);
      scroll-snap-align: start;
    }
    .big-number {
      font-family: var(--font-number);
      font-size: 38px;
      font-weight: 700;
      color: var(--secondary);
    }
    /* FAQ */
    .accordion-item {
      background: white;
      border-radius: 12px;
      margin-bottom: 14px;
      box-shadow: var(--shadow-sm);
      border: 1px solid var(--border);
    }
    .accordion-question {
      width: 100%;
      background: none;
      border: none;
      padding: 20px 24px;
      font-weight: 600;
      font-size: 17px;
      display: flex;
      justify-content: space-between;
      align-items: center;
      color: var(--text-dark);
    }
    .accordion-answer {
      padding: 0 24px 20px;
      color: var(--text-muted);
      display: none;
    }
    .accordion-item.active .accordion-answer {
      display: block;
    }
    /* 表单 */
    .form-section {
      background: #F1F5F9;
    }
    .form-grid {
      display: flex;
      flex-wrap: wrap;
      gap: 40px;
      align-items: center;
    }
    .form-left {
      flex: 1.2;
    }
    .form-right {
      flex: 0.8;
      display: flex;
      flex-direction: column;
      gap: 24px;
    }
    .input-field {
      width: 100%;
      padding: 14px 18px;
      border: 1px solid #CBD5E1;
      border-radius: 8px;
      margin-bottom: 18px;
      font-size: 15px;
    }
    .input-field:focus {
      outline: none;
      border-color: var(--primary);
      box-shadow: 0 0 0 3px rgba(26,95,122,0.2);
    }
    .trust-badge {
      display: flex;
      align-items: center;
      gap: 16px;
      background: white;
      padding: 16px;
      border-radius: 12px;
    }
    /* 页脚 */
    .footer {
      background: #0F172A;
      color: #CBD5E1;
      padding: 60px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 30px;
    }
    .footer a {
      color: #CBD5E1;
    }
    .footer a:hover {
      color: white;
    }
    @media (max-width: 1024px) {
      .footer-grid { grid-template-columns: repeat(2,1fr); }
    }
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .menu-toggle { display: block; }
      .hero h1 { font-size: 34px; }
      .footer-grid { grid-template-columns: 1fr; }
      .compare-panel { flex-direction: column; }
    }
    @media (max-width: 520px) {
      .container { padding: 0 16px; }
      .btn-group { flex-direction: column; align-items: stretch; }
    }