/* roulang page: index */
/* ===== 设计变量与全局重置 ===== */
    :root {
      --primary: #E53935;
      --primary-dark: #C62828;
      --primary-light: #FFEBEE;
      --secondary-green: #1B5E20;
      --secondary-green-light: #E8F5E9;
      --accent-amber: #FFC107;
      --bg-page: #FAFAFA;
      --bg-card: #FFFFFF;
      --bg-dark: #263238;
      --text-primary: #212121;
      --text-secondary: #757575;
      --text-on-dark: #FFFFFF;
      --text-on-dark-muted: #B0BEC5;
      --border-light: #E0E0E0;
      --border-card: #EEEEEE;
      --radius-sm: 8px;
      --radius-md: 12px;
      --radius-lg: 16px;
      --shadow-sm: 0 2px 8px rgba(0,0,0,0.04);
      --shadow-md: 0 8px 24px rgba(0,0,0,0.08);
      --shadow-nav: 0 2px 12px rgba(0,0,0,0.06);
      --transition: all 0.3s ease;
      --max-width: 1200px;
      --nav-height: 64px;
    }
    
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    
    html {
      scroll-behavior: smooth;
      scroll-padding-top: var(--nav-height);
    }
    
    body {
      font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
      background-color: var(--bg-page);
      color: var(--text-primary);
      line-height: 1.8;
      font-size: 1rem;
      -webkit-font-smoothing: antialiased;
    }
    
    a {
      text-decoration: none;
      color: inherit;
      transition: var(--transition);
    }
    
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    
    button, .btn {
      cursor: pointer;
      font-family: inherit;
      border: none;
      outline: none;
      transition: var(--transition);
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      font-weight: 600;
      border-radius: var(--radius-sm);
      white-space: nowrap;
    }
    
    .container {
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 24px;
    }
    
    /* ===== 导航栏 ===== */
    .header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: var(--nav-height);
      background: var(--bg-card);
      z-index: 1000;
      box-shadow: 0 1px 0 rgba(0,0,0,0.05);
      transition: var(--transition);
    }
    
    .header.scrolled {
      box-shadow: var(--shadow-nav);
    }
    
    .nav {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 100%;
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 24px;
    }
    
    .logo {
      display: flex;
      align-items: center;
      gap: 10px;
      font-weight: 700;
      font-size: 1.3rem;
      color: var(--text-primary);
      letter-spacing: 0.5px;
    }
    
    .logo i {
      color: var(--primary);
      font-size: 1.8rem;
    }
    
    .nav-links {
      display: flex;
      align-items: center;
      gap: 32px;
      list-style: none;
    }
    
    .nav-links a {
      font-weight: 500;
      color: var(--text-primary);
      position: relative;
      padding: 4px 0;
    }
    
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: -4px;
      left: 0;
      width: 0;
      height: 3px;
      background: var(--primary);
      transition: width 0.3s ease;
    }
    
    .nav-links a:hover::after,
    .nav-links a.active::after {
      width: 100%;
    }
    
    .btn-nav {
      background: var(--secondary-green);
      color: white;
      padding: 10px 24px;
      border-radius: var(--radius-sm);
      font-weight: 600;
    }
    
    .btn-nav:hover {
      background: #144d18;
    }
    
    .hamburger {
      display: none;
      background: none;
      border: none;
      font-size: 1.8rem;
      color: var(--text-primary);
      padding: 8px;
    }
    
    /* 移动端导航 */
    @media (max-width: 768px) {
      .nav-links {
        position: fixed;
        top: 0;
        right: -100%;
        width: 80%;
        max-width: 320px;
        height: 100vh;
        background: var(--bg-card);
        flex-direction: column;
        justify-content: center;
        gap: 40px;
        padding: 40px;
        box-shadow: -5px 0 25px rgba(0,0,0,0.1);
        transition: right 0.3s ease;
        z-index: 999;
      }
      
      .nav-links.active {
        right: 0;
      }
      
      .nav-links a {
        font-size: 1.2rem;
        font-weight: 600;
      }
      
      .hamburger {
        display: block;
        z-index: 1001;
      }
      
      .btn-nav {
        padding: 14px 32px;
        font-size: 1.1rem;
        width: 100%;
      }
    }
    
    /* ===== 通用板块 ===== */
    section {
      padding: 80px 0;
    }
    
    .section-title {
      text-align: center;
      margin-bottom: 56px;
    }
    
    .section-title h2 {
      font-size: 1.8rem;
      font-weight: 700;
      line-height: 1.4;
      margin-bottom: 16px;
      color: var(--text-primary);
    }
    
    .section-title p {
      color: var(--text-secondary);
      font-size: 1.1rem;
      max-width: 680px;
      margin: 0 auto;
    }
    
    /* ===== Hero 首屏 ===== */
    .hero {
      padding: 120px 0 80px;
      background: var(--bg-card);
      display: flex;
      align-items: center;
    }
    
    .hero-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 60px;
      align-items: center;
    }
    
    .hero-content h1 {
      font-size: 2.5rem;
      font-weight: 700;
      line-height: 1.3;
      margin-bottom: 24px;
      color: var(--text-primary);
    }
    
    .hero-content .subtitle {
      font-size: 1.15rem;
      color: var(--text-secondary);
      margin-bottom: 36px;
      line-height: 1.7;
    }
    
    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    
    .btn-primary {
      background: var(--primary);
      color: white;
      padding: 16px 40px;
      font-size: 1.1rem;
      border-radius: var(--radius-sm);
      box-shadow: 0 4px 12px rgba(229,57,53,0.3);
    }
    
    .btn-primary:hover {
      background: var(--primary-dark);
      box-shadow: 0 6px 18px rgba(229,57,53,0.4);
      transform: translateY(-1px);
    }
    
    .btn-outline {
      background: transparent;
      border: 2px solid var(--primary);
      color: var(--primary);
      padding: 16px 40px;
      font-size: 1.1rem;
    }
    
    .btn-outline:hover {
      background: var(--primary-light);
      border-color: var(--primary-dark);
      color: var(--primary-dark);
    }
    
    .hero-image img {
      border-radius: var(--radius-lg);
      box-shadow: var(--shadow-md);
    }
    
    @media (max-width: 768px) {
      .hero-grid {
        grid-template-columns: 1fr;
        text-align: center;
      }
      .hero-content h1 {
        font-size: 1.8rem;
      }
      .hero-buttons {
        justify-content: center;
      }
    }
    
    /* ===== 痛点区 ===== */
    .pain-points {
      background: var(--bg-page);
    }
    
    .cards-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }
    
    .pain-card {
      background: var(--bg-card);
      padding: 32px;
      border-radius: var(--radius-md);
      box-shadow: var(--shadow-sm);
      border: 1px solid var(--border-card);
      transition: var(--transition);
      text-align: center;
    }
    
    .pain-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-md);
    }
    
    .pain-icon {
      font-size: 2.8rem;
      color: var(--secondary-green);
      margin-bottom: 20px;
    }
    
    .pain-card h3 {
      font-size: 1.2rem;
      margin-bottom: 12px;
    }
    
    .pain-card p {
      color: var(--text-secondary);
      font-size: 0.95rem;
      line-height: 1.7;
    }
    
    /* ===== 解决方案 ===== */
    .solution {
      background: #F5F5F5;
    }
    
    .solution-row {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 60px;
      align-items: center;
      margin-bottom: 60px;
    }
    
    .solution-row:last-child {
      margin-bottom: 0;
    }
    
    .solution-text h3 {
      font-size: 1.4rem;
      margin-bottom: 14px;
      color: var(--text-primary);
    }
    
    .solution-text p {
      color: var(--text-secondary);
    }
    
    .solution-img img {
      border-radius: var(--radius-md);
      box-shadow: var(--shadow-sm);
    }
    
    @media (max-width: 768px) {
      .solution-row {
        grid-template-columns: 1fr;
        gap: 30px;
      }
      .solution-row.reverse {
        display: flex;
        flex-direction: column-reverse;
      }
    }
    
    /* ===== 成果数字 ===== */
    .results {
      background: var(--bg-card);
    }
    
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 20px;
      text-align: center;
    }
    
    .stat-item {
      padding: 24px 16px;
      border: 1px solid var(--border-light);
      border-radius: var(--radius-md);
      background: var(--bg-card);
    }
    
    .stat-number {
      font-size: 2.2rem;
      font-weight: 700;
      color: var(--primary);
      line-height: 1.2;
    }
    
    .stat-label {
      color: var(--text-secondary);
      font-size: 0.95rem;
      margin-top: 8px;
    }
    
    @media (max-width: 768px) {
      .stats-grid {
        grid-template-columns: repeat(2, 1fr);
      }
    }
    
    /* ===== 证言 ===== */
    .testimonials {
      background: var(--bg-page);
    }
    
    .testimonial-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }
    
    .testimonial-card {
      background: var(--bg-card);
      padding: 28px;
      border-radius: var(--radius-md);
      box-shadow: var(--shadow-sm);
      display: flex;
      gap: 16px;
      align-items: flex-start;
      border: 1px solid var(--border-card);
    }
    
    .testimonial-card img {
      width: 48px;
      height: 48px;
      border-radius: 50%;
      object-fit: cover;
    }
    
    .testimonial-text p {
      font-style: italic;
      color: var(--text-primary);
      margin-bottom: 8px;
    }
    
    .testimonial-text .name {
      font-weight: 600;
      color: var(--secondary-green);
      font-style: normal;
    }
    
    @media (max-width: 768px) {
      .testimonial-grid {
        grid-template-columns: 1fr;
      }
    }
    
    /* ===== CTA 转化区 ===== */
    .cta-section {
      background: linear-gradient(135deg, rgba(229,57,53,0.08) 0%, rgba(27,94,32,0.08) 100%);
      text-align: center;
    }
    
    .cta-content h2 {
      font-size: 2rem;
      margin-bottom: 16px;
    }
    
    .cta-buttons {
      display: flex;
      gap: 20px;
      justify-content: center;
      margin-top: 32px;
    }
    
    .btn-cta {
      background: white;
      color: var(--primary);
      border: 2px solid var(--primary);
      padding: 18px 48px;
      font-size: 1.2rem;
      font-weight: 700;
    }
    
    .btn-cta:hover {
      background: var(--primary-light);
    }
    
    /* ===== FAQ ===== */
    .faq {
      background: var(--bg-card);
    }
    
    .accordion {
      max-width: 800px;
      margin: 0 auto;
    }
    
    .accordion-item {
      border: 1px solid var(--border-light);
      border-radius: var(--radius-sm);
      margin-bottom: 12px;
      overflow: hidden;
    }
    
    .accordion-header {
      width: 100%;
      background: var(--bg-card);
      padding: 18px 24px;
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-weight: 600;
      font-size: 1.05rem;
      border: none;
      cursor: pointer;
      text-align: left;
    }
    
    .accordion-header i {
      color: var(--primary);
      transition: transform 0.3s;
    }
    
    .accordion-body {
      padding: 0 24px 18px;
      color: var(--text-secondary);
      display: none;
      line-height: 1.8;
    }
    
    .accordion-item.active .accordion-body {
      display: block;
    }
    
    .accordion-item.active .accordion-header i {
      transform: rotate(45deg);
    }
    
    /* ===== 页脚 ===== */
    .footer {
      background: var(--bg-dark);
      color: var(--text-on-dark);
      padding: 60px 0 30px;
    }
    
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
      margin-bottom: 40px;
    }
    
    .footer-col h4 {
      color: white;
      margin-bottom: 20px;
      font-size: 1.1rem;
    }
    
    .footer-col p, .footer-col a {
      color: var(--text-on-dark-muted);
      font-size: 0.95rem;
      margin-bottom: 12px;
      display: block;
    }
    
    .footer-col a:hover {
      color: white;
    }
    
    .footer-bottom {
      border-top: 1px solid rgba(255,255,255,0.1);
      padding-top: 24px;
      text-align: center;
      color: var(--text-on-dark-muted);
      font-size: 0.9rem;
    }
    
    @media (max-width: 768px) {
      .footer-grid {
        grid-template-columns: 1fr;
        text-align: center;
      }
    }
    
    /* 工具类 */
    .text-center { text-align: center; }
    .mt-16 { margin-top: 16px; }