/* roulang page: index */
:root {
      --primary-green: #1B8C3E;
      --dark-green: #0E5E28;
      --accent-orange: #F5A623;
      --dark-bg: #1A1D23;
      --light-bg: #FAFBF7;
      --light-green-bg: #E8F5E9;
      --text-primary: #1E1E1E;
      --text-secondary: #5F6B7A;
      --border-color: #DDE1E6;
      --card-radius: 12px;
      --btn-radius: 8px;
      --font-heading: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
      --font-body: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    body {
      font-family: var(--font-body);
      background-color: var(--light-bg);
      color: var(--text-primary);
      line-height: 1.7;
      font-size: 16px;
      scroll-behavior: smooth;
    }
    h1, h2, h3 {
      font-family: var(--font-heading);
      font-weight: 700;
      line-height: 1.3;
    }
    a {
      text-decoration: none;
      color: inherit;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 20px;
    }
    /* 导航 */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      background-color: rgba(26, 29, 35, 0.9);
      backdrop-filter: blur(10px);
      z-index: 100;
      transition: background-color 0.3s ease;
    }
    .site-header.scrolled {
      background-color: rgba(26, 29, 35, 1);
    }
    .nav-container {
      display: flex;
      justify-content: space-between;
      align-items: center;
      padding: 16px 20px;
      max-width: 1200px;
      margin: 0 auto;
    }
    .logo {
      font-family: var(--font-heading);
      font-weight: 700;
      font-size: 1.8rem;
      color: #fff;
      display: flex;
      align-items: center;
      gap: 8px;
    }
    .logo-icon {
      width: 28px;
      height: 28px;
      background: var(--primary-green);
      mask: url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24"><circle cx="12" cy="12" r="10" fill="white"/><path d="M12 2 L15 9 L22 9 L16 14 L18 21 L12 17 L6 21 L8 14 L2 9 L9 9 Z" fill="%231B8C3E"/></svg>') center/contain no-repeat;
      display: inline-block;
    }
    .nav-links {
      display: flex;
      gap: 28px;
      align-items: center;
    }
    .nav-links a {
      color: #dddee1;
      font-weight: 500;
      font-size: 1rem;
      transition: color 0.2s;
      position: relative;
    }
    .nav-links a:hover {
      color: var(--primary-green);
    }
    .btn-nav {
      background: var(--primary-green);
      color: #fff !important;
      padding: 10px 22px;
      border-radius: var(--btn-radius);
      font-weight: 600;
    }
    .btn-nav:hover {
      background: var(--dark-green);
    }
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
      background: transparent;
      border: none;
    }
    .hamburger span {
      width: 26px;
      height: 3px;
      background: #fff;
      border-radius: 3px;
      transition: 0.3s;
    }
    @media (max-width: 768px) {
      .nav-links {
        display: none;
        flex-direction: column;
        position: fixed;
        top: 0;
        left: 0;
        width: 100%;
        height: 100vh;
        background: var(--dark-green);
        justify-content: center;
        align-items: center;
        gap: 32px;
        font-size: 1.4rem;
      }
      .nav-links.open {
        display: flex;
      }
      .hamburger {
        display: flex;
        z-index: 110;
      }
    }
    /* 区块间距 */
    section {
      padding: 80px 0;
    }
    @media (max-width: 768px) {
      section {
        padding: 60px 0;
      }
    }
    /* Hero */
    .hero {
      background: var(--dark-bg);
      color: #fff;
      padding-top: 100px;
      padding-bottom: 80px;
      position: relative;
      overflow: hidden;
    }
    .hero::after {
      content: '';
      position: absolute;
      right: 0;
      bottom: 0;
      width: 50%;
      height: 100%;
      background: radial-gradient(circle at 20% 50%, rgba(27,140,62,0.1) 0%, transparent 70%);
      pointer-events: none;
    }
    .hero-grid {
      display: flex;
      align-items: center;
      gap: 48px;
    }
    .hero-text {
      flex: 1;
    }
    .hero-text h1 {
      font-size: 40px;
      margin-bottom: 20px;
    }
    .hero-text p {
      font-size: 18px;
      color: #ccc;
      margin-bottom: 32px;
    }
    .hero-img {
      flex: 1;
    }
    .hero-img img {
      border-radius: 16px;
      box-shadow: 0 20px 35px rgba(0,0,0,0.5);
    }
    @media (max-width: 768px) {
      .hero-grid {
        flex-direction: column;
      }
      .hero-text h1 {
        font-size: 30px;
      }
    }
    .btn-primary {
      background: var(--primary-green);
      color: #fff;
      padding: 14px 32px;
      border-radius: var(--btn-radius);
      font-weight: 700;
      display: inline-block;
      transition: all 0.3s ease;
      border: none;
      cursor: pointer;
      font-size: 16px;
    }
    .btn-primary:hover {
      background: var(--dark-green);
      transform: translateY(-2px);
      box-shadow: 0 8px 18px rgba(0,0,0,0.15);
    }
    /* 痛点 */
    .pain-grid {
      display: grid;
      grid-template-columns: repeat(3,1fr);
      gap: 24px;
    }
    .pain-card {
      background: var(--light-green-bg);
      padding: 28px 22px;
      border-radius: 16px;
      font-weight: 500;
      border-left: 6px solid var(--primary-green);
    }
    @media (max-width: 768px) {
      .pain-grid {
        grid-template-columns: 1fr;
      }
    }
    /* 方案卡片 */
    .solution-grid {
      display: grid;
      grid-template-columns: repeat(2,1fr);
      gap: 28px;
    }
    .sol-card {
      background: #fff;
      padding: 30px;
      border-radius: var(--card-radius);
      box-shadow: 0 4px 14px rgba(0,0,0,0.05);
      transition: 0.3s;
      border-left: 5px solid var(--primary-green);
      display: flex;
      gap: 20px;
    }
    .sol-card:hover {
      transform: translateY(-6px);
      box-shadow: 0 18px 28px rgba(0,0,0,0.1);
    }
    @media (max-width: 768px) {
      .solution-grid {
        grid-template-columns: 1fr;
      }
      .sol-card {
        flex-direction: column;
      }
    }
    /* 成果数字 */
    .results {
      background: var(--dark-bg);
      color: #fff;
    }
    .stats {
      display: flex;
      justify-content: space-around;
      text-align: center;
      flex-wrap: wrap;
    }
    .stat-number {
      font-size: 48px;
      color: var(--accent-orange);
      font-weight: 700;
    }
    /* 证言 */
    .testimonial-grid {
      display: grid;
      grid-template-columns: repeat(3,1fr);
      gap: 24px;
    }
    .testimonial-card {
      background: var(--light-green-bg);
      padding: 28px;
      border-radius: 16px;
    }
    @media (max-width: 768px) {
      .testimonial-grid { grid-template-columns: 1fr; }
    }
    /* FAQ */
    .faq-item {
      background: #fff;
      border: 1px solid var(--border-color);
      border-radius: 12px;
      margin-bottom: 16px;
      overflow: hidden;
    }
    .faq-question {
      padding: 20px 24px;
      font-weight: 700;
      background: var(--light-green-bg);
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      background: #fff;
      padding: 0 24px;
    }
    .faq-answer.open {
      max-height: 200px;
      padding: 20px 24px;
    }
    /* CTA */
    .final-cta {
      background: var(--dark-green);
      color: #fff;
      text-align: center;
    }
    .btn-inverse {
      background: #fff;
      color: var(--primary-green);
      padding: 14px 38px;
      border-radius: var(--btn-radius);
      font-weight: 700;
    }
    footer {
      background: var(--dark-bg);
      color: #aaa;
      padding: 50px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 30px;
    }
    @media (max-width: 768px) {
      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }
    }