/* roulang page: index */
:root {
      --primary-blue: #2C5F7C;
      --accent-orange: #E87A3E;
      --bg-light: #F8FAFB;
      --card-white: #FFFFFF;
      --text-dark: #1A2B34;
      --text-body: #3E4F5A;
      --text-muted: #6B7C89;
      --success-green: #2D9D6B;
      --border-light: #DDE4EA;
      --shadow-sm: 0 2px 12px rgba(44, 95, 124, 0.08);
      --shadow-hover: 0 8px 24px rgba(44, 95, 124, 0.15);
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-input: 6px;
      --font-title: 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', sans-serif;
      --transition-base: 0.2s ease;
      --max-width: 1200px;
    }

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

    body {
      font-family: var(--font-title);
      background-color: var(--bg-light);
      color: var(--text-body);
      line-height: 1.7;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }

    .container {
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 24px;
    }

    /* 导航 */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      background: rgba(255, 255, 255, 0.85);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
      box-shadow: 0 1px 8px rgba(0,0,0,0.02);
      border-bottom: 1px solid var(--border-light);
      z-index: 100;
      transition: var(--transition-base);
    }

    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 72px;
    }

    .logo {
      font-size: 24px;
      font-weight: 700;
      color: var(--primary-blue);
      text-decoration: none;
      letter-spacing: 0.5px;
      display: flex;
      align-items: center;
      gap: 6px;
    }
    .logo span {
      color: var(--accent-orange);
    }

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

    .nav-links a {
      text-decoration: none;
      color: var(--text-body);
      font-weight: 500;
      font-size: 15px;
      transition: color 0.2s;
      white-space: nowrap;
    }

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

    .btn-primary {
      background: var(--accent-orange);
      color: white;
      font-weight: 600;
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      text-decoration: none;
      display: inline-block;
      transition: background 0.2s, transform 0.2s, box-shadow 0.2s;
      border: none;
      cursor: pointer;
      font-size: 15px;
      letter-spacing: 0.3px;
      box-shadow: 0 4px 10px rgba(232, 122, 62, 0.2);
    }

    .btn-primary:hover {
      background: #CF6A32;
      transform: scale(1.03);
      box-shadow: 0 8px 18px rgba(232, 122, 62, 0.3);
    }

    .btn-outline {
      background: transparent;
      border: 2px solid var(--primary-blue);
      color: var(--primary-blue);
      font-weight: 600;
      padding: 10px 26px;
      border-radius: var(--radius-btn);
      text-decoration: none;
      transition: background 0.2s, color 0.2s;
      display: inline-block;
    }

    .btn-outline:hover {
      background: #EBF2F7;
      color: #1d4b63;
    }

    .mobile-menu-btn {
      display: none;
      background: none;
      border: none;
      font-size: 28px;
      color: var(--primary-blue);
      cursor: pointer;
    }

    @media (max-width: 768px) {
      .nav-links {
        display: none;
        position: absolute;
        top: 72px;
        left: 0;
        width: 100%;
        background: white;
        flex-direction: column;
        padding: 24px;
        box-shadow: var(--shadow-sm);
        border-bottom: 1px solid var(--border-light);
        gap: 18px;
      }
      .nav-links.active {
        display: flex;
      }
      .mobile-menu-btn {
        display: block;
      }
      .header-cta-desktop {
        display: none;
      }
      .nav-links .btn-primary {
        width: 100%;
        text-align: center;
        margin-top: 8px;
      }
    }

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

    /* Hero */
    #hero {
      padding: 140px 0 80px;
      background: linear-gradient(135deg, #f0f4f8 0%, #ffffff 100%);
    }

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

    .hero-content {
      flex: 1;
    }

    .hero-content h1 {
      font-size: 44px;
      font-weight: 700;
      color: var(--text-dark);
      line-height: 1.2;
      margin-bottom: 20px;
    }

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

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

    .hero-image {
      flex: 1;
      text-align: center;
    }

    .hero-image img {
      max-width: 100%;
      border-radius: 24px;
      box-shadow: 0 20px 35px rgba(0,0,0,0.08);
    }

    @media (max-width: 768px) {
      .hero-grid {
        flex-direction: column;
      }
      .hero-content h1 {
        font-size: 32px;
      }
    }

    /* 通用板块 */
    section {
      padding: 80px 0;
    }

    .section-title {
      text-align: center;
      margin-bottom: 48px;
    }
    .section-title h2 {
      font-size: 32px;
      font-weight: 600;
      color: var(--text-dark);
      margin-bottom: 12px;
    }
    .section-title p {
      color: var(--text-muted);
      max-width: 600px;
      margin: 0 auto;
    }

    /* 功能卡片 */
    .features-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }

    .feature-card {
      background: var(--card-white);
      padding: 32px;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-sm);
      transition: transform 0.2s, box-shadow 0.2s;
    }

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

    .feature-icon {
      width: 48px;
      height: 48px;
      margin-bottom: 20px;
    }

    .feature-card h3 {
      font-size: 22px;
      font-weight: 600;
      margin-bottom: 12px;
      color: var(--text-dark);
    }

    @media (max-width: 1024px) {
      .features-grid {
        grid-template-columns: repeat(2, 1fr);
      }
    }
    @media (max-width: 640px) {
      .features-grid {
        grid-template-columns: 1fr;
      }
    }

    /* 场景 */
    .scenarios-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 24px;
    }

    .scenario-card {
      background: var(--card-white);
      border-radius: var(--radius-card);
      overflow: hidden;
      display: flex;
      box-shadow: var(--shadow-sm);
      transition: 0.2s;
    }

    .scenario-card:hover {
      box-shadow: var(--shadow-hover);
      transform: translateY(-3px);
    }

    .scenario-img {
      width: 45%;
      object-fit: cover;
    }

    .scenario-text {
      padding: 28px;
      display: flex;
      flex-direction: column;
      justify-content: center;
    }

    .scenario-text h3 {
      font-size: 22px;
      font-weight: 600;
      margin-bottom: 10px;
    }

    .tag {
      background: #eef3f7;
      color: var(--primary-blue);
      padding: 4px 12px;
      border-radius: 20px;
      font-size: 13px;
      font-weight: 500;
      display: inline-block;
      margin-top: 10px;
      width: fit-content;
    }

    @media (max-width: 768px) {
      .scenarios-grid {
        grid-template-columns: 1fr;
      }
      .scenario-card {
        flex-direction: column;
      }
      .scenario-img {
        width: 100%;
        height: 200px;
      }
    }

    /* 案例 */
    .cases-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }

    .case-card {
      background: var(--card-white);
      padding: 28px;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-sm);
      text-align: center;
    }

    .case-number {
      font-size: 42px;
      font-weight: 700;
      color: var(--accent-orange);
      margin-bottom: 10px;
    }

    .case-title {
      font-weight: 600;
      font-size: 20px;
      margin-bottom: 8px;
    }

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

    /* 价格 */
    .pricing-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
      align-items: start;
    }

    .pricing-card {
      background: white;
      border-radius: var(--radius-card);
      padding: 32px;
      box-shadow: var(--shadow-sm);
      text-align: center;
      position: relative;
      border: 1px solid var(--border-light);
    }

    .pricing-card.recommended {
      border: 2px solid var(--success-green);
      box-shadow: 0 10px 25px rgba(45,157,107,0.1);
    }

    .badge {
      background: var(--success-green);
      color: white;
      font-size: 13px;
      padding: 4px 16px;
      border-radius: 20px;
      position: absolute;
      top: -12px;
      left: 50%;
      transform: translateX(-50%);
      font-weight: 600;
    }

    .price {
      font-size: 36px;
      font-weight: 700;
      color: var(--primary-blue);
      margin: 20px 0;
    }

    .feature-list {
      list-style: none;
      text-align: left;
      margin: 24px 0;
    }

    .feature-list li {
      margin-bottom: 10px;
      display: flex;
      align-items: center;
      gap: 8px;
    }

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

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

    .faq-item {
      border-bottom: 1px solid var(--border-light);
      padding: 16px 0;
      cursor: pointer;
    }

    .faq-question {
      font-weight: 600;
      font-size: 18px;
      color: var(--primary-blue);
      display: flex;
      justify-content: space-between;
      align-items: center;
    }

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

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

    /* 联系 */
    .contact-form {
      max-width: 600px;
      margin: 0 auto;
      display: flex;
      flex-direction: column;
      gap: 20px;
    }

    .contact-form input,
    .contact-form textarea {
      padding: 14px;
      border: 1px solid var(--border-light);
      border-radius: var(--radius-input);
      font-family: inherit;
      font-size: 16px;
      transition: 0.2s;
    }

    .contact-form input:focus,
    .contact-form textarea:focus {
      outline: none;
      border-color: var(--primary-blue);
      box-shadow: 0 0 0 3px rgba(44,95,124,0.1);
    }

    .btn-submit {
      background: var(--accent-orange);
      color: white;
      font-weight: 600;
      padding: 15px;
      border: none;
      border-radius: var(--radius-btn);
      cursor: pointer;
      font-size: 17px;
    }

    /* 页脚 */
    .site-footer {
      background: #1E3F52;
      color: #d0dbe4;
      padding: 48px 0 24px;
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 32px;
    }

    .footer-links a {
      color: #cbd5e0;
      text-decoration: none;
      display: block;
      margin-bottom: 8px;
    }

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