/* roulang page: index */
:root {
      --primary-green: #0A8F3C;
      --dark-charcoal: #1E1E1E;
      --accent-cyan: #00E676;
      --warm-gray-bg: #F5F5F0;
      --card-bg: #FFFFFF;
      --text-body: #4A4A4A;
      --text-light: #B0B0B0;
      --card-radius: 16px;
      --card-shadow: 0 4px 20px rgba(0,0,0,0.04);
      --card-shadow-hover: 0 12px 32px rgba(0,0,0,0.1);
      --btn-radius: 12px;
      --transition: all 0.3s ease;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    body {
      font-family: 'Noto Sans SC', 'PingFang SC', 'Microsoft YaHei', sans-serif;
      background-color: var(--warm-gray-bg);
      color: var(--text-body);
      line-height: 1.7;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
      padding-bottom: 70px; /* for mobile bottom tab */
    }
    .inter-font {
      font-family: 'Inter', 'Noto Sans SC', sans-serif;
    }
    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 24px;
    }
    h1, h2, h3, h4 {
      color: var(--dark-charcoal);
      font-weight: 700;
    }
    h1 {
      font-size: 44px;
      line-height: 1.2;
      font-weight: 800;
      letter-spacing: -0.5px;
    }
    h2 {
      font-size: 32px;
      line-height: 1.3;
      margin-bottom: 16px;
    }
    h3 {
      font-size: 22px;
      line-height: 1.4;
      font-weight: 600;
    }
    p {
      margin-bottom: 1.2rem;
      color: var(--text-body);
    }
    a {
      text-decoration: none;
      color: var(--primary-green);
      transition: var(--transition);
    }
    a:hover {
      color: #067A2E;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    /* 导航 */
    .desktop-nav {
      background: var(--dark-charcoal);
      position: fixed;
      top: 0;
      left: 0;
      right: 0;
      z-index: 100;
      padding: 0 24px;
      height: 72px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      box-shadow: 0 4px 12px rgba(0,0,0,0.1);
    }
    .logo {
      font-size: 28px;
      font-weight: 800;
      color: white;
      letter-spacing: 1px;
      display: flex;
      align-items: center;
      gap: 8px;
    }
    .logo i {
      color: var(--accent-cyan);
      font-size: 32px;
    }
    .nav-links {
      display: flex;
      gap: 32px;
      align-items: center;
    }
    .nav-links a {
      color: #CCCCCC;
      font-weight: 500;
      font-size: 15px;
      transition: var(--transition);
      position: relative;
      padding: 8px 0;
    }
    .nav-links a:hover,
    .nav-links a.active {
      color: white;
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 3px;
      background: var(--accent-cyan);
      transition: width 0.25s ease;
    }
    .nav-links a:hover::after,
    .nav-links a.active::after {
      width: 100%;
    }
    /* 移动端底部Tab */
    .mobile-bottom-nav {
      display: none;
      position: fixed;
      bottom: 0;
      left: 0;
      right: 0;
      background: white;
      border-top: 1px solid #e2e2e2;
      z-index: 110;
      padding: 8px 16px;
      justify-content: space-around;
      box-shadow: 0 -2px 10px rgba(0,0,0,0.04);
    }
    .mobile-tab {
      display: flex;
      flex-direction: column;
      align-items: center;
      color: #888;
      font-size: 12px;
      transition: var(--transition);
      gap: 4px;
    }
    .mobile-tab i {
      font-size: 20px;
    }
    .mobile-tab.active {
      color: var(--primary-green);
      font-weight: 600;
    }
    /* 区块间距 */
    section {
      padding: 100px 0;
      scroll-margin-top: 80px;
    }
    /* 卡片 */
    .card {
      background: var(--card-bg);
      border-radius: var(--card-radius);
      box-shadow: var(--card-shadow);
      padding: 32px;
      transition: var(--transition);
      height: 100%;
    }
    .card:hover {
      transform: translateY(-6px);
      box-shadow: var(--card-shadow-hover);
    }
    .badge {
      background: var(--accent-cyan);
      color: var(--dark-charcoal);
      font-weight: 700;
      padding: 6px 14px;
      border-radius: 30px;
      font-size: 14px;
      display: inline-block;
      letter-spacing: 0.3px;
    }
    .btn-primary {
      background: var(--primary-green);
      color: white;
      border: none;
      padding: 14px 32px;
      border-radius: var(--btn-radius);
      font-weight: 600;
      font-size: 16px;
      cursor: pointer;
      transition: var(--transition);
      display: inline-block;
      text-align: center;
      box-shadow: 0 4px 12px rgba(10,143,60,0.2);
    }
    .btn-primary:hover {
      background: #067A2E;
      box-shadow: 0 0 20px rgba(10,143,60,0.35);
      color: white;
      transform: translateY(-1px);
    }
    .btn-outline {
      background: transparent;
      border: 2px solid var(--primary-green);
      color: var(--primary-green);
      padding: 12px 30px;
      border-radius: var(--btn-radius);
      font-weight: 600;
      transition: var(--transition);
      display: inline-block;
    }
    .btn-outline:hover {
      background: rgba(10,143,60,0.05);
      color: #067A2E;
      border-color: #067A2E;
    }
    .data-badge-number {
      font-size: 48px;
      font-weight: 800;
      line-height: 1;
      color: var(--accent-cyan);
      font-family: 'Inter', sans-serif;
    }
    /* Hero */
    .hero-section {
      background: linear-gradient(135deg, #f5f5f0 0%, #ffffff 100%);
      position: relative;
      overflow: hidden;
      padding-top: 120px;
      padding-bottom: 80px;
    }
    .hero-grid {
      display: flex;
      align-items: center;
      gap: 60px;
    }
    .hero-left {
      flex: 1;
    }
    .hero-right {
      flex: 1;
      position: relative;
    }
    .hero-illustration {
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      min-height: 380px;
      border-radius: 32px;
      box-shadow: 0 20px 40px rgba(0,0,0,0.08);
      position: relative;
    }
    .floating-badge {
      position: absolute;
      bottom: 20px;
      right: -10px;
      background: white;
      padding: 12px 24px;
      border-radius: 40px;
      box-shadow: 0 10px 25px rgba(0,0,0,0.1);
      font-weight: 700;
      color: var(--dark-charcoal);
      display: flex;
      align-items: center;
      gap: 8px;
    }
    /* 痛点卡片 */
    .pain-card {
      border-left: 5px solid var(--primary-green);
    }
    /* 成果深色区 */
    .results-section {
      background: var(--dark-charcoal);
      color: white;
    }
    .results-section h2, .results-section .text-light {
      color: #ddd;
    }
    /* FAQ */
    .faq-item {
      border-bottom: 1px solid #e0e0e0;
      padding: 18px 0;
      cursor: pointer;
    }
    .faq-question {
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-weight: 600;
      color: var(--dark-charcoal);
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      color: #5a5a5a;
      padding-right: 30px;
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      margin-top: 12px;
    }
    /* CTA渐变 */
    .cta-gradient {
      background: linear-gradient(135deg, #0A8F3C 0%, #1E1E1E 100%);
      border-radius: 32px;
      padding: 70px 40px;
      text-align: center;
      color: white;
    }
    footer {
      background: var(--dark-charcoal);
      color: #B0B0B0;
      padding: 60px 0 20px;
    }
    /* 响应式 */
    @media (max-width: 1024px) {
      h1 { font-size: 38px; }
      h2 { font-size: 28px; }
      .hero-grid { flex-direction: column; }
    }
    @media (max-width: 768px) {
      .desktop-nav { display: none; }
      .mobile-bottom-nav { display: flex; }
      body { padding-bottom: 80px; }
      section { padding: 70px 0; }
      h1 { font-size: 32px; }
      h2 { font-size: 26px; }
      h3 { font-size: 20px; }
      .container { padding: 0 20px; }
      .hero-section { padding-top: 40px; }
      .data-badge-number { font-size: 36px; }
    }
    @media (max-width: 480px) {
      .card { padding: 24px; }
      .btn-primary, .btn-outline { width: 100%; margin-bottom: 12px; }
    }