/* roulang page: index */
:root {
      --primary: #C8102E;
      --primary-hover: #A00D24;
      --secondary: #1A1A1A;
      --bg: #FAFAFA;
      --card-bg: #FFFFFF;
      --text: #2D2D2D;
      --text-muted: #6B6B6B;
      --border: #E5E5E5;
      --success: #0F7B4E;
      --shadow-sm: 0 2px 12px rgba(0,0,0,0.04);
      --shadow-hover: 0 8px 30px rgba(0,0,0,0.08);
      --shadow-nav: 0 2px 20px rgba(0,0,0,0.06);
      --radius-card: 16px;
      --radius-btn: 12px;
      --radius-input: 8px;
      --font-cn: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", sans-serif;
      --font-en: "Inter", "SF Pro Display", system-ui, sans-serif;
      --section-padding: 120px 0;
    }

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

    body {
      font-family: var(--font-cn);
      background: var(--bg);
      color: var(--text);
      line-height: 1.6;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }

    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 20px;
      width: 100%;
    }

    h1, h2, h3, h4 {
      font-family: var(--font-cn);
      font-weight: 600;
    }

    a {
      text-decoration: none;
      color: inherit;
      transition: color 0.2s;
    }

    img {
      max-width: 100%;
      height: auto;
      display: block;
    }

    button, input, textarea {
      font-family: var(--font-cn);
      font-size: 16px;
      outline: none;
    }

    /* 导航 */
    .navbar {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 64px;
      background: transparent;
      transition: background 0.3s, box-shadow 0.3s;
      z-index: 1000;
      padding: 0 24px;
      display: flex;
      align-items: center;
      justify-content: space-between;
    }

    .navbar.scrolled {
      background: var(--card-bg);
      box-shadow: var(--shadow-nav);
    }

    .logo {
      font-size: 24px;
      font-weight: 700;
      color: var(--primary);
      letter-spacing: 0.5px;
      transition: color 0.2s;
      z-index: 1001;
    }

    .nav-links {
      display: flex;
      gap: 32px;
      align-items: center;
      list-style: none;
    }

    .nav-links a {
      font-size: 15px;
      font-weight: 500;
      color: var(--text);
      position: relative;
      padding: 4px 0;
      transition: color 0.2s;
    }

    .nav-links a:hover,
    .nav-links a.active {
      color: var(--primary);
    }

    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: -8px;
      left: 0;
      width: 100%;
      height: 3px;
      background: var(--primary);
      transform: scaleX(0);
      transition: transform 0.2s;
      border-radius: 2px;
    }

    .nav-links a.active::after {
      transform: scaleX(1);
    }

    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      background: none;
      border: none;
      cursor: pointer;
      z-index: 1001;
      padding: 5px;
    }

    .hamburger span {
      width: 24px;
      height: 2px;
      background: var(--secondary);
      border-radius: 2px;
      transition: 0.3s;
    }

    .mobile-menu {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100vh;
      background: var(--card-bg);
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      gap: 36px;
      transform: translateY(-100%);
      transition: transform 0.3s ease;
      z-index: 999;
      list-style: none;
    }

    .mobile-menu.active {
      transform: translateY(0);
    }

    .mobile-menu a {
      font-size: 22px;
      font-weight: 600;
      color: var(--text);
    }

    .mobile-menu-close {
      position: absolute;
      top: 24px;
      right: 24px;
      background: none;
      border: none;
      font-size: 32px;
      color: var(--text);
      cursor: pointer;
    }

    /* Hero */
    .hero {
      padding: 160px 0 100px;
      background: linear-gradient(135deg, #FAFAFA 0%, #FFFFFF 100%);
      position: relative;
      overflow: hidden;
    }

    .hero .container {
      display: flex;
      align-items: center;
      gap: 60px;
    }

    .hero-content {
      flex: 1 1 55%;
    }

    .hero h1 {
      font-size: 48px;
      line-height: 1.2;
      font-weight: 700;
      color: var(--secondary);
      margin-bottom: 20px;
    }

    .hero h1 span {
      color: var(--primary);
    }

    .hero-subtitle {
      font-size: 18px;
      color: var(--text-muted);
      margin-bottom: 32px;
      max-width: 500px;
    }

    .hero-buttons {
      display: flex;
      gap: 16px;
      margin-bottom: 40px;
      flex-wrap: wrap;
    }

    .btn-primary {
      background: var(--primary);
      color: white;
      border: none;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      cursor: pointer;
      transition: background 0.2s, transform 0.2s;
      display: inline-block;
    }

    .btn-primary:hover {
      background: var(--primary-hover);
      transform: translateY(-2px);
    }

    .btn-outline {
      background: transparent;
      border: 2px solid var(--primary);
      color: var(--primary);
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      cursor: pointer;
      transition: background 0.2s, color 0.2s;
    }

    .btn-outline:hover {
      background: var(--primary);
      color: white;
    }

    .hero-stats {
      display: flex;
      gap: 32px;
      flex-wrap: wrap;
    }

    .stat-item {
      display: flex;
      flex-direction: column;
    }

    .stat-number {
      font-family: var(--font-en);
      font-size: 28px;
      font-weight: 700;
      color: var(--primary);
    }

    .stat-label {
      font-size: 14px;
      color: var(--text-muted);
    }

    .hero-visual {
      flex: 1 1 45%;
      display: flex;
      justify-content: center;
      align-items: center;
    }

    .hero-image {
      width: 400px;
      height: 400px;
      background: radial-gradient(circle at 30% 30%, #e02b4b, var(--primary));
      border-radius: 32px;
      display: flex;
      align-items: center;
      justify-content: center;
      color: white;
      font-size: 72px;
      box-shadow: 0 20px 40px rgba(200,16,46,0.2);
    }

    /* 板块通用 */
    section {
      padding: var(--section-padding);
    }

    .section-title {
      font-size: 36px;
      font-weight: 600;
      color: var(--secondary);
      text-align: center;
      margin-bottom: 16px;
    }

    .section-subtitle {
      text-align: center;
      color: var(--text-muted);
      max-width: 600px;
      margin: 0 auto 48px;
      font-size: 17px;
    }

    /* 数据看板 */
    .data-board {
      background: var(--card-bg);
    }

    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
    }

    .stat-card {
      background: var(--card-bg);
      padding: 28px;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-sm);
      transition: transform 0.3s, box-shadow 0.3s;
    }

    .stat-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
    }

    .stat-big {
      font-family: var(--font-en);
      font-size: 40px;
      font-weight: 700;
      color: var(--primary);
    }

    .stat-desc {
      font-size: 14px;
      color: var(--text-muted);
      margin: 8px 0 12px;
    }

    .trend-up {
      color: var(--success);
      font-weight: 600;
      font-size: 14px;
    }

    /* 服务矩阵 */
    .services-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }

    .service-card {
      background: var(--card-bg);
      padding: 32px;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-sm);
      transition: 0.3s;
      border-left: 4px solid transparent;
    }

    .service-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-hover);
      border-left-color: var(--primary);
    }

    .service-icon {
      font-size: 40px;
      margin-bottom: 20px;
      color: var(--primary);
    }

    .service-card h3 {
      font-size: 22px;
      margin-bottom: 10px;
    }

    .service-card p {
      color: var(--text-muted);
      font-size: 14px;
      margin-bottom: 16px;
    }

    .service-link {
      font-weight: 600;
      color: var(--primary);
      font-size: 15px;
    }

    /* 对比区 */
    .compare-section {
      background: #F9F9F9;
    }

    .compare-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 32px;
    }

    .compare-card {
      padding: 32px;
      border-radius: var(--radius-card);
      background: white;
    }

    .compare-card.old {
      background: #f2f2f2;
      color: #555;
    }

    .compare-card.new {
      background: white;
      border: 1px solid var(--border);
      box-shadow: var(--shadow-sm);
    }

    .compare-item {
      display: flex;
      align-items: center;
      gap: 12px;
      margin-bottom: 16px;
      font-size: 16px;
    }

    .icon-red { color: var(--primary); font-weight: bold; }
    .icon-green { color: var(--success); font-weight: bold; }
    .strikethrough { text-decoration: line-through; color: #999; }

    /* FAQ */
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
    }

    .faq-item {
      border-bottom: 1px solid var(--border);
    }

    .faq-question {
      width: 100%;
      background: none;
      border: none;
      padding: 20px 0;
      font-size: 16px;
      font-weight: 500;
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
      color: var(--text);
      transition: color 0.2s;
    }

    .faq-question.active {
      color: var(--primary);
    }

    .faq-icon {
      font-size: 20px;
      transition: transform 0.2s;
    }

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      padding: 0 0;
      color: var(--text-muted);
      font-size: 15px;
    }

    .faq-answer.open {
      max-height: 200px;
      padding-bottom: 20px;
    }

    /* CTA */
    .cta-band {
      background: var(--secondary);
      text-align: center;
      color: white;
    }

    .cta-band h2 {
      color: white;
      margin-bottom: 12px;
    }

    .cta-form {
      display: flex;
      gap: 16px;
      max-width: 700px;
      margin: 32px auto 0;
      flex-wrap: wrap;
      justify-content: center;
    }

    .cta-form input {
      flex: 1 1 200px;
      padding: 14px;
      border-radius: var(--radius-input);
      border: 1px solid var(--border);
      background: white;
    }

    .cta-form input:focus {
      border-color: var(--primary);
    }

    .btn-submit {
      background: var(--primary);
      color: white;
      border: none;
      padding: 14px 28px;
      border-radius: var(--radius-input);
      font-weight: 600;
      cursor: pointer;
      transition: background 0.2s;
    }

    .btn-submit:hover {
      background: var(--primary-hover);
    }

    /* Footer */
    .footer {
      background: #F5F5F5;
      padding: 60px 0 30px;
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
    }

    .footer-logo {
      font-size: 22px;
      font-weight: 700;
      color: var(--primary);
      margin-bottom: 12px;
    }

    .footer-desc {
      color: var(--text-muted);
      font-size: 14px;
    }

    .footer h4 {
      font-size: 16px;
      margin-bottom: 16px;
    }

    .footer ul {
      list-style: none;
    }

    .footer li {
      margin-bottom: 8px;
      font-size: 14px;
      color: var(--text-muted);
    }

    .footer a:hover {
      color: var(--primary);
    }

    .copyright {
      text-align: center;
      margin-top: 40px;
      padding-top: 20px;
      border-top: 1px solid var(--border);
      font-size: 13px;
      color: var(--text-muted);
    }

    @media (max-width: 1024px) {
      .hero .container { flex-direction: column; text-align: center; }
      .hero-buttons { justify-content: center; }
      .hero-stats { justify-content: center; }
      .stats-grid { grid-template-columns: repeat(2, 1fr); }
      .services-grid { grid-template-columns: repeat(2, 1fr); }
      .compare-grid { grid-template-columns: 1fr; }
      .footer-grid { grid-template-columns: 1fr 1fr; }
    }

    @media (max-width: 768px) {
      .nav-links { display: none; }
      .hamburger { display: flex; }
      .hero h1 { font-size: 32px; }
      .stats-grid { grid-template-columns: 1fr; }
      .services-grid { grid-template-columns: 1fr; }
      .cta-form { flex-direction: column; }
      .footer-grid { grid-template-columns: 1fr; }
    }