/* roulang page: index */
:root {
      --primary-deep: #1E2D2F;
      --accent-copper: #C49A6C;
      --accent-copper-hover: #B0874F;
      --deep-green: #2D5A4B;
      --bg-warm: #F7F5F2;
      --bg-light-green: #E8EDEB;
      --text-primary: #1E2D2F;
      --text-secondary: #4A5A5C;
      --text-light: #8A9A9C;
      --white: #FFFFFF;
      --border-light: rgba(0,0,0,0.06);
      --border-medium: rgba(0,0,0,0.08);
      --shadow-card: 0 4px 12px rgba(0,0,0,0.04);
      --shadow-card-hover: 0 8px 24px rgba(0,0,0,0.08);
      --radius-card: 16px;
      --radius-btn: 8px;
      --radius-circle: 50%;
      --max-width: 1280px;
      --nav-height: 72px;
      --font-heading: 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', sans-serif;
      --font-body: 'Inter', 'PingFang SC', 'Microsoft YaHei', sans-serif;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    html {
      scroll-behavior: smooth;
    }
    body {
      font-family: var(--font-body);
      color: var(--text-primary);
      background-color: var(--bg-warm);
      line-height: 1.7;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }
    .container {
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 24px;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: color 0.2s ease;
    }
    button, .btn {
      cursor: pointer;
      font-family: var(--font-body);
      border: none;
      background: none;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
    }
    /* 导航 */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: var(--nav-height);
      background: var(--white);
      border-bottom: 1px solid var(--border-medium);
      z-index: 1000;
      box-shadow: 0 2px 6px rgba(0,0,0,0.02);
    }
    .nav-container {
      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-family: var(--font-heading);
      font-weight: 700;
      font-size: 1.6rem;
      color: var(--primary-deep);
      letter-spacing: 0.5px;
    }
    .logo i {
      color: var(--accent-copper);
      font-size: 2rem;
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 36px;
      list-style: none;
    }
    .nav-links a {
      font-weight: 500;
      font-size: 0.95rem;
      color: var(--primary-deep);
      position: relative;
      padding: 6px 0;
      transition: color 0.2s;
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--accent-copper);
      transition: width 0.2s ease;
    }
    .nav-links a:hover {
      color: var(--accent-copper);
    }
    .nav-links a:hover::after {
      width: 100%;
    }
    .hamburger {
      display: none;
      font-size: 1.8rem;
      color: var(--primary-deep);
      background: none;
      border: none;
    }
    @media (max-width: 768px) {
      .nav-links {
        position: fixed;
        top: var(--nav-height);
        left: 0;
        width: 100%;
        background: var(--bg-warm);
        flex-direction: column;
        align-items: center;
        gap: 32px;
        padding: 48px 24px;
        transform: translateY(-120%);
        transition: transform 0.35s ease;
        box-shadow: 0 8px 20px rgba(0,0,0,0.05);
        z-index: 999;
      }
      .nav-links.active {
        transform: translateY(0);
      }
      .hamburger {
        display: block;
      }
    }
    /* Hero */
    .hero {
      padding: calc(var(--nav-height) + 60px) 0 80px;
      background: linear-gradient(135deg, #F7F5F2 0%, #E8EDEB 100%);
    }
    .hero-grid {
      display: flex;
      align-items: center;
      gap: 60px;
    }
    .hero-content {
      flex: 1;
    }
    .hero-content h1 {
      font-family: var(--font-heading);
      font-size: 3.5rem;
      font-weight: 700;
      line-height: 1.2;
      color: var(--primary-deep);
      margin-bottom: 24px;
    }
    .hero-content .subtitle {
      font-size: 1.125rem;
      color: var(--text-secondary);
      margin-bottom: 32px;
      max-width: 480px;
    }
    .btn-primary {
      background: var(--accent-copper);
      color: var(--white);
      font-weight: 600;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-size: 1rem;
      transition: background 0.2s, transform 0.1s;
    }
    .btn-primary:hover {
      background: var(--accent-copper-hover);
      transform: translateY(-1px);
    }
    .hero-visual {
      flex: 1;
      position: relative;
    }
    .hero-visual img {
      border-radius: 24px;
      box-shadow: 0 20px 30px rgba(0,0,0,0.06);
    }
    .circle-accent {
      position: absolute;
      top: -30px;
      right: -20px;
      width: 140px;
      height: 140px;
      background: rgba(196,154,108,0.15);
      border-radius: var(--radius-circle);
      z-index: 0;
    }
    @media (max-width: 1024px) {
      .hero-content h1 {
        font-size: 2.8rem;
      }
    }
    @media (max-width: 768px) {
      .hero-grid {
        flex-direction: column;
        text-align: center;
      }
      .hero-content h1 {
        font-size: 2.25rem;
      }
      .hero-visual {
        margin-top: 40px;
      }
    }
    /* 通用板块 */
    .section {
      padding: 80px 0;
    }
    .section-title {
      font-family: var(--font-heading);
      font-size: 2.25rem;
      font-weight: 600;
      color: var(--primary-deep);
      margin-bottom: 20px;
      text-align: center;
    }
    .section-sub {
      color: var(--text-secondary);
      text-align: center;
      max-width: 600px;
      margin: 0 auto 48px;
    }
    /* 核心优势 */
    .cards-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 32px;
      align-items: start;
    }
    .adv-card {
      background: var(--white);
      border: 1px solid var(--border-light);
      border-radius: var(--radius-card);
      padding: 36px 28px;
      box-shadow: var(--shadow-card);
      transition: all 0.25s ease;
    }
    .adv-card:hover {
      box-shadow: var(--shadow-card-hover);
      transform: translateY(-2px);
      border-color: var(--accent-copper);
    }
    .adv-icon {
      width: 56px;
      height: 56px;
      background: var(--bg-light-green);
      border-radius: var(--radius-circle);
      display: flex;
      align-items: center;
      justify-content: center;
      margin-bottom: 24px;
      color: var(--accent-copper);
      font-size: 1.8rem;
    }
    .adv-card h3 {
      font-size: 1.5rem;
      font-weight: 500;
      margin-bottom: 16px;
    }
    @media (max-width: 768px) {
      .cards-grid {
        grid-template-columns: 1fr;
      }
    }
    /* 成果数据 */
    .results-bg {
      background: var(--bg-light-green);
    }
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
      text-align: center;
    }
    .stat-item .number {
      font-size: 2.8rem;
      font-weight: 700;
      color: var(--accent-copper);
    }
    @media (max-width: 768px) {
      .stats-grid {
        grid-template-columns: repeat(2, 1fr);
      }
    }
    /* 证言 */
    .testimonial-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 32px;
    }
    .testimonial-card {
      background: #F0EFEC;
      border-radius: 20px;
      padding: 32px;
      position: relative;
    }
    .quote-icon {
      color: var(--accent-copper);
      opacity: 0.5;
      font-size: 2.5rem;
      margin-bottom: 16px;
    }
    .testimonial-text {
      font-style: italic;
      margin-bottom: 24px;
    }
    .user-info {
      display: flex;
      align-items: center;
      gap: 12px;
    }
    .user-info img {
      width: 48px;
      height: 48px;
      border-radius: var(--radius-circle);
      object-fit: cover;
    }
    @media (max-width: 768px) {
      .testimonial-grid {
        grid-template-columns: 1fr;
      }
    }
    /* FAQ */
    .faq-container {
      max-width: 800px;
      margin: 0 auto;
    }
    .faq-item {
      border-bottom: 1px solid var(--border-medium);
      padding: 20px 0;
    }
    .faq-question {
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-weight: 600;
      cursor: pointer;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.35s ease, padding 0.3s;
      color: var(--text-secondary);
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding-top: 12px;
    }
    /* CTA */
    .cta-band {
      background: var(--primary-deep);
      color: var(--white);
      text-align: center;
      padding: 80px 24px;
    }
    .cta-band h2 {
      font-size: 2.25rem;
      margin-bottom: 16px;
    }
    .btn-secondary {
      border: 2px solid var(--accent-copper);
      color: var(--accent-copper);
      padding: 12px 30px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      transition: 0.2s;
    }
    .btn-secondary:hover {
      background: var(--accent-copper);
      color: white;
    }
    /* Footer */
    .site-footer {
      background: var(--primary-deep);
      color: #E2E0DD;
      padding: 60px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
    }
    .footer-links a {
      display: block;
      margin-bottom: 8px;
    }
    @media (max-width: 768px) {
      .footer-grid {
        grid-template-columns: 1fr;
      }
    }