/* roulang page: index */
:root {
      --primary: #0D8C4A;
      --primary-light: #1AB563;
      --primary-deep: #063D20;
      --accent: #F47B20;
      --accent-hover: #e06d16;
      --bg-page: #F7F9F8;
      --bg-card: #FFFFFF;
      --text-main: #2C3E35;
      --text-muted: #6B7F73;
      --border-light: #DDE5E0;
      --shadow-card: 0 4px 20px rgba(13, 140, 74, 0.06);
      --shadow-hover: 0 12px 32px rgba(13, 140, 74, 0.12);
      --radius-card: 20px;
      --radius-btn: 12px;
      --radius-badge: 24px;
      --max-width: 1200px;
      --nav-height: 68px;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    body {
      font-family: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", system-ui, -apple-system, sans-serif;
      background-color: var(--bg-page);
      color: var(--text-main);
      line-height: 1.7;
      font-size: 16px;
      scroll-behavior: smooth;
    }
    .container {
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 24px;
    }
    h1, h2, h3 {
      font-weight: 700;
      letter-spacing: -0.5px;
    }
    h2 {
      font-size: 2.25rem;
      margin-bottom: 1rem;
      line-height: 1.3;
    }
    @media (max-width: 768px) {
      h2 { font-size: 1.8rem; }
    }
    a {
      text-decoration: none;
      color: inherit;
    }
    img {
      max-width: 100%;
      display: block;
      height: auto;
    }
    button, .btn {
      cursor: pointer;
      font-family: "Inter", "PingFang SC", "Microsoft YaHei", sans-serif;
      font-weight: 600;
      letter-spacing: 0.5px;
      border: none;
      outline: none;
      transition: all 0.2s ease;
    }
    /* 导航 */
    .nav {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: var(--nav-height);
      background: rgba(255, 255, 255, 0.92);
      backdrop-filter: blur(8px);
      box-shadow: 0 2px 16px rgba(0,0,0,0.04);
      z-index: 100;
      display: flex;
      align-items: center;
    }
    .nav .container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
    }
    .logo {
      font-size: 1.5rem;
      font-weight: 700;
      color: var(--primary);
      display: flex;
      align-items: center;
      gap: 6px;
    }
    .logo span {
      background: linear-gradient(135deg, #0D8C4A, #1AB563);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
    }
    .nav-links {
      display: flex;
      gap: 2rem;
      align-items: center;
    }
    .nav-links a {
      font-weight: 500;
      color: var(--text-main);
      transition: color 0.2s;
    }
    .nav-links a:hover {
      color: var(--primary);
    }
    .btn-primary {
      background: linear-gradient(135deg, #0D8C4A 0%, #1AB563 100%);
      color: white;
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      font-size: 1rem;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      box-shadow: 0 4px 12px rgba(13,140,74,0.2);
    }
    .btn-primary:hover {
      background: linear-gradient(135deg, #0A6E3A 0%, #12994F 100%);
      box-shadow: 0 6px 18px rgba(244,123,32,0.25);
      transform: translateY(-1px);
    }
    .btn-outline {
      background: transparent;
      border: 2px solid var(--primary);
      color: var(--primary);
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      font-size: 1rem;
    }
    .btn-outline:hover {
      background: rgba(13,140,74,0.08);
    }
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
    }
    .hamburger span {
      width: 26px;
      height: 2.5px;
      background: var(--text-main);
      border-radius: 2px;
      transition: 0.3s;
    }
    @media (max-width: 768px) {
      .nav-links {
        display: none;
        position: fixed;
        top: var(--nav-height);
        left: 0;
        width: 100%;
        background: white;
        flex-direction: column;
        padding: 2rem;
        box-shadow: 0 12px 24px rgba(0,0,0,0.08);
      }
      .nav-links.active {
        display: flex;
      }
      .hamburger {
        display: flex;
      }
    }
    /* Hero */
    .hero {
      background: linear-gradient(180deg, #f2f7f4 0%, #ffffff 100%);
      padding: 140px 0 100px;
    }
    .hero .container {
      display: flex;
      align-items: center;
      gap: 3rem;
    }
    .hero-content {
      flex: 1;
    }
    .hero h1 {
      font-size: 3.2rem;
      font-weight: 700;
      line-height: 1.2;
      margin-bottom: 1.5rem;
      color: var(--text-main);
    }
    .hero .subtitle {
      font-size: 1.25rem;
      color: var(--text-muted);
      margin-bottom: 2rem;
      max-width: 500px;
    }
    .hero-buttons {
      display: flex;
      gap: 1rem;
      flex-wrap: wrap;
    }
    .hero-image {
      flex: 1;
      display: flex;
      justify-content: center;
    }
    .hero-image img {
      max-width: 320px;
      border-radius: 32px;
      box-shadow: 0 20px 40px rgba(13,140,74,0.15);
      background: #eef4f0;
    }
    @media (max-width: 768px) {
      .hero .container {
        flex-direction: column;
        text-align: center;
      }
      .hero h1 { font-size: 2.2rem; }
      .hero-image img { max-width: 260px; }
    }
    section {
      padding: 100px 0;
    }
    @media (max-width: 768px) {
      section { padding: 70px 0; }
    }
    .section-title {
      text-align: center;
      margin-bottom: 3rem;
    }
    /* 痛点 */
    .problem-grid {
      display: flex;
      gap: 2rem;
      justify-content: center;
      margin-top: 2rem;
      flex-wrap: wrap;
    }
    .problem-item {
      display: flex;
      gap: 1rem;
      align-items: flex-start;
      max-width: 300px;
    }
    .problem-icon {
      font-size: 2rem;
      color: var(--accent);
    }
    /* 解决方案卡片 */
    .cards-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 2rem;
      margin-top: 2.5rem;
    }
    .solution-card {
      background: var(--bg-card);
      border-radius: var(--radius-card);
      padding: 2rem;
      box-shadow: var(--shadow-card);
      transition: all 0.25s;
      display: flex;
      flex-direction: column;
    }
    .solution-card:hover {
      box-shadow: var(--shadow-hover);
      transform: translateY(-6px);
    }
    .solution-card.middle {
      border-top: 5px solid var(--primary);
    }
    .card-img {
      width: 100%;
      aspect-ratio: 16/9;
      background: #eef4f0;
      border-radius: 12px;
      margin-bottom: 1.5rem;
      object-fit: cover;
    }
    .badge {
      background: var(--accent);
      color: white;
      padding: 6px 18px;
      border-radius: 24px;
      font-size: 0.85rem;
      font-weight: 700;
      display: inline-flex;
      align-items: center;
      gap: 4px;
      margin-top: 1rem;
      align-self: flex-start;
    }
    @media (max-width: 1024px) {
      .cards-grid { grid-template-columns: repeat(2, 1fr); }
    }
    @media (max-width: 640px) {
      .cards-grid { grid-template-columns: 1fr; }
    }
    /* 成果左右交替 */
    .result-row {
      display: flex;
      align-items: center;
      gap: 3rem;
      margin-bottom: 4rem;
    }
    .result-row.reverse {
      flex-direction: row-reverse;
    }
    .result-text {
      flex: 1;
    }
    .big-number {
      font-size: 3.5rem;
      font-weight: 800;
      background: linear-gradient(135deg, #0D8C4A, #1AB563);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
      line-height: 1.1;
    }
    .result-image {
      flex: 1;
      background: #eef4f0;
      border-radius: 24px;
      overflow: hidden;
      box-shadow: 0 8px 24px rgba(0,0,0,0.05);
    }
    @media (max-width: 768px) {
      .result-row, .result-row.reverse {
        flex-direction: column;
      }
    }
    /* 证言 */
    .testimonials-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 2rem;
      margin-top: 2rem;
    }
    .testimonial-card {
      background: #F7F9F8;
      border: 1px solid var(--border-light);
      border-radius: 16px;
      padding: 2rem;
    }
    .stars {
      color: var(--accent);
      letter-spacing: 2px;
    }
    .avatar {
      width: 48px;
      height: 48px;
      border-radius: 50%;
      background: #dde5e0;
      margin-bottom: 1rem;
    }
    @media (max-width: 768px) {
      .testimonials-grid { grid-template-columns: 1fr; }
    }
    /* FAQ */
    .faq-item {
      border-bottom: 1px solid var(--border-light);
      padding: 20px 0;
    }
    .faq-question {
      font-weight: 600;
      font-size: 1.1rem;
      display: flex;
      justify-content: space-between;
      cursor: pointer;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.35s ease;
      color: var(--text-muted);
    }
    .faq-item.open .faq-answer {
      max-height: 200px;
      margin-top: 12px;
    }
    .plus-icon {
      font-size: 1.5rem;
      transition: transform 0.3s;
    }
    .faq-item.open .plus-icon {
      transform: rotate(45deg);
    }
    /* CTA */
    .cta-section {
      background: linear-gradient(135deg, #0D8C4A 0%, #1AB563 100%);
      color: white;
      text-align: center;
      padding: 90px 0;
    }
    .cta-buttons {
      display: flex;
      gap: 1.5rem;
      justify-content: center;
      margin: 2rem 0;
    }
    .btn-white {
      background: white;
      color: var(--primary);
      padding: 14px 32px;
      border-radius: var(--radius-btn);
    }
    /* 页脚 */
    .footer {
      background: linear-gradient(135deg, #063D20 0%, #0D8C4A 100%);
      color: #C8DCD0;
      padding: 60px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 2rem;
    }
    .footer a {
      color: #C8DCD0;
    }
    .footer a:hover { color: white; }
    @media (max-width: 768px) {
      .footer-grid { grid-template-columns: 1fr 1fr; }
    }
    .copyright {
      margin-top: 2rem;
      text-align: center;
      font-size: 0.9rem;
      color: #a0bfa8;
    }