/* roulang page: index */
/* 设计变量与全局重置 */
    :root {
      --primary: #0A2540;
      --primary-light: #1a3a5c;
      --secondary: #00A86B;
      --secondary-hover: #008C5A;
      --accent: #FF6B35;
      --bg: #F7F9FC;
      --card-bg: #FFFFFF;
      --text: #1A1A2E;
      --text-secondary: #5A6A7E;
      --text-on-dark: #FFFFFF;
      --border: #E8ECF1;
      --shadow-sm: 0 2px 12px rgba(10,37,64,0.06);
      --shadow-hover: 0 8px 30px rgba(10,37,64,0.12);
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-input: 6px;
      --radius-table: 16px;
      --font-sans: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", "Noto Sans SC", sans-serif;
      --font-number: "Inter", "Roboto", system-ui;
    }
    
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    
    html {
      scroll-behavior: smooth;
    }
    
    body {
      font-family: var(--font-sans);
      background-color: var(--bg);
      color: var(--text);
      line-height: 1.7;
      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;
    }
    
    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 24px;
    }
    
    /* 按钮系统 */
    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      font-weight: 600;
      border-radius: var(--radius-btn);
      transition: all 0.25s ease;
      cursor: pointer;
      border: none;
      font-size: 16px;
      padding: 12px 28px;
      letter-spacing: 0.3px;
    }
    .btn-primary {
      background-color: var(--secondary);
      color: white;
      box-shadow: 0 4px 10px rgba(0,168,107,0.25);
    }
    .btn-primary:hover {
      background-color: var(--secondary-hover);
      transform: translateY(-2px);
      box-shadow: 0 8px 18px rgba(0,168,107,0.35);
    }
    .btn-outline {
      background: transparent;
      border: 2px solid var(--primary);
      color: var(--primary);
    }
    .btn-outline:hover {
      background-color: var(--primary);
      color: white;
    }
    .btn-light {
      background: white;
      color: var(--primary);
      font-weight: 600;
    }
    .btn-light:hover {
      background: #f0f4f8;
    }
    
    /* 导航 */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      background: rgba(255,255,255,0.85);
      backdrop-filter: blur(10px);
      transition: box-shadow 0.3s, background 0.3s;
      border-bottom: 1px solid transparent;
    }
    .site-header.scrolled {
      background: rgba(255,255,255,0.98);
      box-shadow: 0 4px 20px rgba(0,0,0,0.04);
      border-bottom: 1px solid var(--border);
    }
    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 72px;
    }
    .logo {
      font-size: 22px;
      font-weight: 700;
      color: var(--primary);
      letter-spacing: -0.3px;
      display: flex;
      align-items: center;
      gap: 6px;
    }
    .logo i {
      color: var(--secondary);
      font-size: 26px;
    }
    .nav-menu {
      display: flex;
      align-items: center;
      gap: 32px;
      list-style: none;
    }
    .nav-menu a {
      font-weight: 500;
      color: var(--text);
      font-size: 15px;
      transition: color 0.2s;
      position: relative;
    }
    .nav-menu a::after {
      content: '';
      position: absolute;
      bottom: -6px;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--secondary);
      transition: width 0.3s;
    }
    .nav-menu a:hover {
      color: var(--secondary);
    }
    .nav-menu a:hover::after {
      width: 100%;
    }
    .nav-cta {
      margin-left: 8px;
    }
    .hamburger {
      display: none;
      font-size: 28px;
      cursor: pointer;
      color: var(--primary);
    }
    .mobile-panel {
      position: fixed;
      top: 0;
      right: 0;
      width: 80%;
      max-width: 360px;
      height: 100vh;
      background: white;
      box-shadow: -10px 0 30px rgba(0,0,0,0.08);
      transform: translateX(100%);
      transition: transform 0.4s cubic-bezier(0.23, 1, 0.32, 1);
      z-index: 2000;
      padding: 24px;
      display: flex;
      flex-direction: column;
    }
    .mobile-panel.active {
      transform: translateX(0);
    }
    .mobile-panel .close-panel {
      align-self: flex-end;
      font-size: 30px;
      margin-bottom: 30px;
    }
    .mobile-panel a {
      display: block;
      padding: 14px 0;
      font-size: 18px;
      border-bottom: 1px solid var(--border);
      font-weight: 500;
    }
    
    /* 区块间距 */
    section {
      padding: 100px 0;
    }
    
    /* Hero */
    .hero {
      padding-top: 150px;
      padding-bottom: 80px;
      background: linear-gradient(180deg, #f0f4fa 0%, var(--bg) 100%);
    }
    .hero-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 60px;
      align-items: center;
    }
    .hero-content h1 {
      font-size: 48px;
      line-height: 1.2;
      font-weight: 700;
      color: var(--primary);
      margin-bottom: 20px;
      letter-spacing: -0.5px;
    }
    .hero-content .subtitle {
      font-size: 18px;
      color: var(--text-secondary);
      margin-bottom: 32px;
    }
    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
      margin-bottom: 28px;
    }
    .trust-badge {
      display: flex;
      align-items: center;
      gap: 12px;
      color: var(--text-secondary);
      font-size: 14px;
    }
    .trust-badge i {
      color: var(--secondary);
      font-size: 20px;
    }
    .hero-image {
      position: relative;
      border-radius: 24px;
      overflow: hidden;
      box-shadow: 0 20px 40px rgba(10,37,64,0.15);
      background: linear-gradient(135deg, #0A2540 0%, #1a3a5c 100%);
    }
    .hero-image img {
      width: 100%;
      height: auto;
      opacity: 0.9;
      mix-blend-mode: overlay;
    }
    
    /* 数据条 */
    .stats-bar {
      background: white;
      border-top: 1px solid var(--border);
      border-bottom: 1px solid var(--border);
      padding: 28px 0;
    }
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      text-align: center;
    }
    .stat-item .stat-number {
      font-family: var(--font-number);
      font-size: 32px;
      font-weight: 700;
      color: var(--primary);
      display: block;
    }
    .stat-item .stat-label {
      font-size: 14px;
      color: var(--text-secondary);
      margin-top: 6px;
    }
    
    /* 亮点网格 */
    .features-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
      margin-top: 40px;
    }
    .feature-card {
      background: var(--card-bg);
      padding: 28px;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-sm);
      transition: all 0.3s ease;
      border: 1px solid transparent;
    }
    .feature-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-hover);
      border-color: var(--secondary);
    }
    .feature-icon {
      width: 52px;
      height: 52px;
      background: rgba(0,168,107,0.1);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      color: var(--secondary);
      font-size: 24px;
      margin-bottom: 20px;
    }
    .feature-card h3 {
      font-size: 22px;
      margin-bottom: 12px;
    }
    .feature-card p {
      color: var(--text-secondary);
      margin-bottom: 16px;
    }
    .feature-link {
      font-weight: 600;
      color: var(--secondary);
      font-size: 15px;
    }
    
    /* 案例瀑布流 */
    .masonry-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
      margin-top: 40px;
    }
    .case-card {
      background: white;
      border-radius: var(--radius-card);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
      transition: 0.3s;
      border: 1px solid var(--border);
    }
    .case-card:hover {
      box-shadow: var(--shadow-hover);
      border-color: var(--primary);
    }
    .case-img {
      height: 160px;
      background-size: cover;
      background-position: center;
    }
    .case-info {
      padding: 20px;
    }
    .case-info h4 {
      font-size: 18px;
      margin-bottom: 8px;
    }
    .tags {
      display: flex;
      flex-wrap: wrap;
      gap: 8px;
      margin-top: 12px;
    }
    .tag {
      background: #eef2f6;
      color: var(--primary);
      padding: 4px 10px;
      border-radius: 20px;
      font-size: 12px;
      font-weight: 600;
    }
    
    /* 对比表 */
    .pricing-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
      margin-top: 40px;
    }
    .plan-card {
      background: white;
      border-radius: var(--radius-table);
      padding: 32px 24px;
      box-shadow: var(--shadow-sm);
      border: 1px solid var(--border);
      text-align: center;
    }
    .plan-card.featured {
      border: 2px solid var(--secondary);
      background: #f9fffc;
      position: relative;
    }
    .badge {
      background: var(--accent);
      color: white;
      padding: 6px 16px;
      border-radius: 20px;
      font-size: 13px;
      font-weight: 700;
      display: inline-block;
      margin-bottom: 12px;
    }
    .price {
      font-family: var(--font-number);
      font-size: 40px;
      font-weight: 700;
      color: var(--primary);
      margin: 16px 0;
    }
    .feature-list {
      list-style: none;
      text-align: left;
      margin: 24px 0;
    }
    .feature-list li {
      padding: 8px 0;
      border-bottom: 1px solid #f0f0f0;
    }
    
    /* FAQ */
    .faq-grid {
      display: grid;
      grid-template-columns: 1fr 1.2fr;
      gap: 60px;
      align-items: start;
    }
    .accordion-item {
      border-bottom: 1px solid var(--border);
      padding: 20px 0;
      cursor: pointer;
    }
    .accordion-header {
      display: flex;
      justify-content: space-between;
      font-weight: 600;
      font-size: 18px;
    }
    .accordion-content {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      color: var(--text-secondary);
    }
    
    /* CTA横幅 */
    .cta-banner {
      background: var(--primary);
      color: white;
      text-align: center;
      border-radius: 24px;
      padding: 70px 24px;
    }
    
    /* 页脚 */
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1.5fr;
      gap: 40px;
    }
    .copyright {
      border-top: 1px solid var(--border);
      margin-top: 40px;
      padding-top: 24px;
      text-align: center;
      color: var(--text-secondary);
    }
    
    /* 响应式 */
    @media (max-width: 992px) {
      .hero-grid, .faq-grid { grid-template-columns: 1fr; }
      .features-grid { grid-template-columns: repeat(2,1fr); }
      .masonry-grid { grid-template-columns: repeat(2,1fr); }
      .pricing-grid { grid-template-columns: 1fr; max-width: 500px; margin-left: auto; margin-right: auto; }
      .footer-grid { grid-template-columns: 1fr 1fr; }
    }
    @media (max-width: 768px) {
      .nav-menu { display: none; }
      .hamburger { display: block; }
      .features-grid, .masonry-grid { grid-template-columns: 1fr; }
      .stats-grid { grid-template-columns: repeat(2,1fr); gap: 20px; }
      .hero-content h1 { font-size: 36px; }
    }