/* roulang page: index */
:root {
      --green-field: #2E7D32;
      --warm-stone: #F5F2EB;
      --signal-white: #FFFFFF;
      --charcoal: #1E1E1E;
      --soft-black: #2C2C2C;
      --success-green: #43A047;
      --glow-green: #76FF03;
      --light-mint: #E8F5E9;
      --border-light: #E0E0E0;
      --gray-mute: #9E9E9E;
      --shadow-card: 0 4px 20px rgba(0,0,0,0.04);
      --shadow-hover: 0 8px 30px rgba(0,0,0,0.08);
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-tag: 6px;
      --max-width: 1200px;
      --transition-smooth: 0.25s ease;
    }

    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }

    body {
      font-family: 'PingFang SC', 'Microsoft YaHei', 'Segoe UI', sans-serif;
      background-color: var(--warm-stone);
      color: var(--charcoal);
      line-height: 1.7;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }

    .container {
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 32px;
    }

    h1, h2, h3 {
      font-family: 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', sans-serif;
      letter-spacing: -0.2px;
    }

    h1 {
      font-size: 48px;
      line-height: 56px;
      font-weight: 700;
    }

    h2 {
      font-size: 36px;
      line-height: 44px;
      font-weight: 600;
      color: var(--charcoal);
    }

    h3 {
      font-size: 20px;
      line-height: 28px;
      font-weight: 500;
    }

    a {
      text-decoration: none;
      color: inherit;
    }

    img {
      display: block;
      max-width: 100%;
    }

    button, .btn {
      cursor: pointer;
      font-family: inherit;
      transition: var(--transition-smooth);
    }

    section {
      padding: 80px 0;
    }

    /* 导航 */
    .header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 100;
      background: rgba(245, 242, 235, 0.92);
      backdrop-filter: blur(12px);
      height: 72px;
      border-bottom: 1px solid rgba(0,0,0,0.05);
      transition: background 0.2s;
    }

    .nav {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 100%;
    }

    .logo {
      font-size: 26px;
      font-weight: 700;
      color: var(--green-field);
      letter-spacing: -0.3px;
      display: flex;
      align-items: center;
      gap: 8px;
    }
    .logo-icon {
      width: 28px;
      height: 28px;
      background: var(--green-field);
      mask: url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100"><circle cx="50" cy="50" r="38" fill="none" stroke="white" stroke-width="17" /></svg>') center/cover;
      background-size: cover;
    }

    .nav-links {
      display: flex;
      gap: 32px;
      font-weight: 500;
      color: var(--charcoal);
    }
    .nav-links a {
      font-size: 16px;
      transition: color 0.2s;
    }
    .nav-links a:hover {
      color: var(--green-field);
    }

    .btn-primary {
      background: var(--green-field);
      color: var(--signal-white);
      border: none;
      border-radius: var(--radius-btn);
      padding: 12px 28px;
      font-weight: 600;
      font-size: 16px;
      white-space: nowrap;
    }
    .btn-primary:hover {
      background: #1B5E20;
      box-shadow: 0 4px 12px rgba(46,125,50,0.3);
      transform: translateY(-1px);
    }

    .hamburger {
      display: none;
      flex-direction: column;
      gap: 6px;
      background: none;
      border: none;
      width: 32px;
    }
    .hamburger span {
      display: block;
      height: 3px;
      background: var(--charcoal);
      border-radius: 3px;
    }
    .mobile-menu {
      display: none;
    }

    /* 首屏 */
    .hero {
      padding: 140px 0 100px;
      background: radial-gradient(circle at 30% 30%, #263238, #1E1E1E);
      position: relative;
      overflow: hidden;
    }
    .hero::before {
      content: "";
      position: absolute;
      width: 200%;
      height: 200%;
      top: -50%;
      left: -30%;
      background-image: repeating-linear-gradient(45deg, rgba(255,255,255,0.02) 0px, transparent 8px, rgba(255,255,255,0.015) 16px);
      transform: rotate(10deg);
      pointer-events: none;
    }
    .hero-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 60px;
      align-items: center;
      position: relative;
      z-index: 2;
    }
    .hero-title {
      color: var(--signal-white);
      margin-bottom: 24px;
    }
    .hero-title span {
      color: var(--success-green);
      border-bottom: 3px solid var(--success-green);
      display: inline-block;
    }
    .hero-sub {
      font-size: 18px;
      color: rgba(255,255,255,0.75);
      max-width: 460px;
      margin-bottom: 28px;
    }
    .hero-stats {
      display: flex;
      gap: 32px;
      margin-bottom: 36px;
    }
    .stat-item h3 {
      font-family: 'DIN Alternate','PingFang SC', sans-serif;
      font-size: 28px;
      color: var(--success-green);
      font-weight: 700;
    }
    .hero-actions {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .btn-outline {
      background: transparent;
      border: 2px solid var(--green-field);
      color: var(--signal-white);
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      font-weight: 600;
    }
    .btn-outline:hover {
      background: var(--green-field);
      color: white;
    }
    .hero-art {
      display: flex;
      justify-content: center;
    }

    /* 板块标题 */
    .section-title {
      text-align: center;
      margin-bottom: 48px;
    }
    .section-title h2 {
      display: inline-block;
    }

    /* 卡片网格 */
    .grid-3 {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .card {
      background: var(--signal-white);
      border-radius: var(--radius-card);
      padding: 32px;
      box-shadow: var(--shadow-card);
      border: 1px solid var(--border-light);
      transition: all 0.2s;
    }
    .card:hover {
      box-shadow: var(--shadow-hover);
      border-color: var(--green-field);
      transform: translateY(-4px);
    }
    .card-icon {
      font-size: 30px;
      margin-bottom: 18px;
    }
    .pain-badge {
      width: 4px;
      height: 100%;
      background: var(--green-field);
      border-radius: 4px;
      margin-right: 16px;
      transition: width 0.2s;
    }
    .pain-row {
      display: flex;
      align-items: flex-start;
    }
    .pain-text h3 {
      margin-bottom: 8px;
    }

    /* 方案卡片 */
    .solution-list {
      list-style: none;
      margin-top: 16px;
    }
    .solution-list li {
      display: flex;
      align-items: center;
      gap: 10px;
      font-size: 15px;
      margin-bottom: 8px;
    }
    .divider-line {
      width: 24px;
      height: 2px;
      background: var(--green-field);
      margin: 12px 0 16px;
    }

    /* 成果数字 */
    .results-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      text-align: center;
    }
    .big-number {
      font-family: 'DIN Alternate','PingFang SC', sans-serif;
      font-size: 48px;
      font-weight: 700;
      color: var(--green-field);
    }

    /* 证言 */
    .testimonial-block {
      display: flex;
      gap: 24px;
      margin-bottom: 36px;
      position: relative;
      padding-left: 40px;
    }
    .testimonial-block::before {
      content: "“";
      font-size: 60px;
      color: var(--green-field);
      opacity: 0.2;
      position: absolute;
      left: 0;
      top: -10px;
      font-weight: 700;
    }
    .quote-text {
      font-size: 18px;
      font-style: italic;
      color: var(--charcoal);
    }

    /* FAQ */
    .faq-item {
      background: white;
      border-radius: 10px;
      margin-bottom: 12px;
      border: 1px solid var(--border-light);
    }
    .faq-question {
      padding: 20px;
      font-weight: 500;
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.35s ease, background 0.2s;
      background: white;
    }
    .faq-item.active .faq-answer {
      max-height: 300px;
      background: var(--light-mint);
    }
    .faq-answer-inner {
      padding: 20px;
    }

    /* 终极CTA */
    .dark-cta {
      background: #1E1E1E;
      text-align: center;
      padding: 80px 0;
    }
    .dark-cta h2 {
      color: white;
    }

    .footer-grid {
      display: flex;
      justify-content: space-between;
      align-items: center;
      color: var(--charcoal);
      font-size: 14px;
    }

    @media (max-width: 1024px) {
      .grid-3 { grid-template-columns: repeat(2, 1fr); }
      .results-grid { grid-template-columns: repeat(2, 1fr); }
    }
    @media (max-width: 768px) {
      .nav-links, .nav .btn-primary { display: none; }
      .hamburger { display: flex; }
      .hero-grid { grid-template-columns: 1fr; }
      h1 { font-size: 32px; line-height: 38px; }
      .grid-3 { grid-template-columns: 1fr; }
      .container { padding: 0 20px; }
    }