/* roulang page: index */
:root {
      --primary: #C8102E;
      --primary-hover: #a50d24;
      --secondary: #1A1A2E;
      --accent: #F5A623;
      --accent-hover: #e0950f;
      --bg-light: #F8F9FA;
      --text-main: #212529;
      --text-muted: #6C757D;
      --border: #DEE2E6;
      --white: #ffffff;
      --shadow-card: 0 4px 12px rgba(0,0,0,0.06);
      --shadow-card-hover: 0 8px 24px rgba(0,0,0,0.1);
      --shadow-nav: 0 2px 8px rgba(0,0,0,0.05);
      --radius-sm: 8px;
      --radius-md: 12px;
      --radius-lg: 16px;
      --font-sans: "Noto Sans SC", -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
      --font-number: "Inter", "Noto Sans SC", -apple-system, sans-serif;
    }

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

    body {
      font-family: var(--font-sans);
      background-color: var(--white);
      color: var(--text-main);
      line-height: 1.75;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }

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

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

    button, input {
      font-family: inherit;
      font-size: inherit;
      border: none;
      outline: none;
      background: transparent;
    }

    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
      width: 100%;
    }

    /* 导航 */
    #nav {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 64px;
      background: var(--white);
      border-bottom: 1px solid var(--border);
      z-index: 1000;
      display: flex;
      align-items: center;
      transition: box-shadow 0.3s ease;
    }

    #nav.scrolled {
      box-shadow: var(--shadow-nav);
    }

    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
    }

    .logo {
      font-size: 20px;
      font-weight: 700;
      color: var(--primary);
      letter-spacing: 0.5px;
      white-space: nowrap;
    }

    .nav-links {
      display: flex;
      align-items: center;
      gap: 28px;
    }

    .nav-link {
      font-size: 15px;
      font-weight: 500;
      color: var(--text-main);
      transition: color 0.2s;
      white-space: nowrap;
    }

    .nav-link:hover {
      color: var(--primary);
    }

    .btn-primary {
      background: var(--primary);
      color: var(--white);
      font-weight: 600;
      padding: 12px 32px;
      border-radius: var(--radius-sm);
      display: inline-flex;
      align-items: center;
      justify-content: center;
      transition: background 0.2s, transform 0.1s;
      cursor: pointer;
      border: none;
      white-space: nowrap;
    }

    .btn-primary:hover {
      background: var(--primary-hover);
      transform: translateY(-1px);
    }

    .btn-outline {
      background: transparent;
      border: 2px solid var(--primary);
      color: var(--primary);
      font-weight: 600;
      padding: 10px 28px;
      border-radius: var(--radius-sm);
      transition: all 0.2s;
      cursor: pointer;
    }

    .btn-outline:hover {
      background: rgba(200,16,46,0.08);
    }

    .btn-accent {
      background: var(--accent);
      color: #1A1A2E;
      font-weight: 700;
      padding: 14px 36px;
      border-radius: var(--radius-sm);
      box-shadow: 0 4px 10px rgba(245,166,35,0.3);
      transition: all 0.25s;
      cursor: pointer;
    }

    .btn-accent:hover {
      background: var(--accent-hover);
      box-shadow: 0 6px 16px rgba(245,166,35,0.4);
      transform: translateY(-2px);
    }

    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
      background: transparent;
      border: none;
      padding: 4px;
    }

    .hamburger span {
      width: 24px;
      height: 2px;
      background: var(--text-main);
      transition: 0.3s;
      display: block;
    }

    /* 移动端导航 */
    @media (max-width: 768px) {
      .nav-links {
        position: fixed;
        top: 64px;
        left: 0;
        width: 100%;
        background: rgba(26,26,46,0.97);
        flex-direction: column;
        align-items: center;
        gap: 24px;
        padding: 40px 0;
        transform: translateY(-120%);
        transition: transform 0.35s ease;
        backdrop-filter: blur(8px);
      }
      .nav-links.active {
        transform: translateY(0);
      }
      .nav-link {
        color: white;
        font-size: 18px;
      }
      .hamburger {
        display: flex;
      }
      .btn-primary.desktop-only {
        display: none;
      }
      .nav-links .btn-primary {
        display: inline-flex;
      }
    }

    @media (min-width: 769px) {
      .mobile-only-btn {
        display: none;
      }
    }

    /* Hero */
    #hero {
      background: linear-gradient(135deg, #1A1A2E 0%, #2D2D44 100%);
      min-height: 90vh;
      display: flex;
      align-items: center;
      padding-top: 64px;
      position: relative;
      overflow: hidden;
    }

    .hero-grid {
      display: flex;
      align-items: center;
      gap: 48px;
      width: 100%;
    }

    .hero-text {
      flex: 1;
      color: white;
    }

    .hero-text h1 {
      font-size: 36px;
      font-weight: 700;
      line-height: 1.3;
      margin-bottom: 20px;
    }

    .hero-sub {
      font-size: 18px;
      color: #CED4DA;
      margin-bottom: 32px;
      line-height: 1.6;
    }

    .hero-visual {
      flex: 1;
      display: flex;
      justify-content: center;
    }

    .hero-visual img {
      max-height: 380px;
      border-radius: var(--radius-lg);
      box-shadow: 0 20px 40px rgba(0,0,0,0.3);
    }

    @media (max-width: 768px) {
      .hero-grid {
        flex-direction: column;
        text-align: center;
        gap: 32px;
      }
      .hero-text h1 {
        font-size: 28px;
      }
      .hero-visual img {
        max-height: 260px;
      }
    }

    /* 通用区块 */
    section {
      padding: 80px 0;
    }

    .section-title {
      font-size: 28px;
      font-weight: 600;
      margin-bottom: 16px;
      line-height: 1.4;
      color: var(--text-main);
      text-align: center;
    }

    .section-sub {
      color: var(--text-muted);
      text-align: center;
      max-width: 700px;
      margin: 0 auto 48px;
    }

    /* 数据看板 */
    #dashboard {
      background: var(--bg-light);
    }

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

    .stat-card {
      background: white;
      border-radius: var(--radius-md);
      padding: 32px 16px;
      text-align: center;
      box-shadow: var(--shadow-card);
    }

    .stat-number {
      font-size: 40px;
      font-weight: 700;
      color: var(--primary);
      font-family: var(--font-number);
      margin-bottom: 8px;
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 6px;
    }

    .stat-label {
      color: var(--text-muted);
      font-size: 15px;
    }

    @media (max-width: 768px) {
      .stats-grid {
        grid-template-columns: 1fr 1fr;
      }
      .stat-number {
        font-size: 32px;
      }
    }

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

    .service-card {
      background: white;
      padding: 32px 24px;
      border-radius: var(--radius-md);
      box-shadow: var(--shadow-card);
      transition: all 0.25s;
      text-align: center;
    }

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

    .service-icon {
      width: 56px;
      height: 56px;
      background: rgba(200,16,46,0.08);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      margin: 0 auto 16px;
      color: var(--primary);
      font-size: 28px;
    }

    .service-title {
      font-weight: 600;
      font-size: 18px;
      margin-bottom: 8px;
    }

    .service-desc {
      color: var(--text-muted);
      font-size: 15px;
    }

    @media (max-width: 768px) {
      .services-grid {
        grid-template-columns: 1fr;
      }
    }

    /* 对比区 */
    #comparison {
      background: var(--secondary);
      color: white;
    }

    .compare-wrapper {
      display: flex;
      gap: 32px;
      align-items: stretch;
    }

    .compare-col {
      flex: 1;
      background: rgba(255,255,255,0.05);
      border-radius: var(--radius-md);
      padding: 40px 32px;
    }

    .compare-col.right {
      background: rgba(200,16,46,0.15);
      border: 1px solid var(--primary);
    }

    .compare-title {
      font-size: 22px;
      font-weight: 600;
      margin-bottom: 24px;
      display: flex;
      align-items: center;
      gap: 8px;
    }

    .compare-list {
      list-style: none;
    }

    .compare-list li {
      margin-bottom: 16px;
      display: flex;
      align-items: flex-start;
      gap: 10px;
    }

    .icon-fail {
      color: #adb5bd;
      font-weight: bold;
    }

    .icon-check {
      color: var(--accent);
      font-weight: bold;
    }

    @media (max-width: 768px) {
      .compare-wrapper {
        flex-direction: column;
      }
    }

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

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

    .faq-question {
      width: 100%;
      text-align: left;
      padding: 20px 8px;
      font-weight: 600;
      font-size: 17px;
      background: transparent;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
      color: var(--text-main);
    }

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      padding: 0 8px;
      color: var(--text-muted);
    }

    .faq-item.active .faq-answer {
      max-height: 200px;
      padding-bottom: 16px;
    }

    .faq-icon {
      font-size: 20px;
      transition: transform 0.3s;
    }

    .faq-item.active .faq-icon {
      transform: rotate(45deg);
    }

    /* CTA */
    #cta {
      background: linear-gradient(135deg, #C8102E 0%, #a50d24 100%);
      color: white;
      text-align: center;
    }

    .cta-form {
      display: flex;
      justify-content: center;
      gap: 12px;
      margin-top: 24px;
      flex-wrap: wrap;
    }

    .cta-input {
      padding: 14px 20px;
      border-radius: var(--radius-sm);
      border: 1px solid transparent;
      min-width: 260px;
      background: white;
    }

    .cta-input:focus {
      border-color: var(--accent);
      box-shadow: 0 0 0 3px rgba(245,166,35,0.3);
    }

    /* 页脚 */
    #footer {
      background: var(--secondary);
      color: #CED4DA;
      padding: 40px 0;
      text-align: center;
    }

    .footer-links {
      display: flex;
      justify-content: center;
      gap: 24px;
      margin: 16px 0;
      flex-wrap: wrap;
    }

    .footer-links a {
      color: #CED4DA;
      font-size: 14px;
    }

    .footer-links a:hover {
      color: white;
    }