/* roulang page: index */
:root {
      --primary-deep-green: #1A3C2A;
      --accent-gold: #F5A623;
      --accent-gold-hover: #E09515;
      --bg-warm-white: #FAFAF8;
      --bg-light-grayish: #F0EDE8;
      --text-primary: #1E1E1E;
      --text-secondary: #5C5C5C;
      --text-muted: #8C8C8C;
      --card-bg: #FFFFFF;
      --card-border: #E8E5E0;
      --footer-bg: #1A2E22;
      --footer-text: #D0D0C8;
      --footer-link-hover: #F5A623;
      
      --radius-card: 12px;
      --radius-list: 8px;
      --radius-btn: 6px;
      --shadow-card: 0 1px 3px rgba(0,0,0,0.04);
      --shadow-card-hover: 0 8px 24px rgba(0,0,0,0.08);
      --shadow-nav: 0 2px 8px rgba(0,0,0,0.03);
      --transition-base: 0.25s ease;
      
      --font-chinese: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", sans-serif;
      --font-english: "Inter", system-ui, -apple-system, sans-serif;
      
      --header-height: 64px;
      --section-gap: 80px;
      --container-max: 1280px;
    }
    
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    
    html {
      scroll-behavior: smooth;
      font-size: 16px;
    }
    
    body {
      font-family: var(--font-chinese);
      background-color: var(--bg-warm-white);
      color: var(--text-primary);
      line-height: 1.75;
      letter-spacing: 0.01em;
    }
    
    /* 英数混排优化 */
    body, button, input, textarea {
      font-family: var(--font-chinese);
    }
    .num, .stat, .english-text {
      font-family: var(--font-english);
    }
    
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    
    a {
      text-decoration: none;
      color: inherit;
      transition: color var(--transition-base);
    }
    
    /* 容器 */
    .container {
      width: 100%;
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 32px;
    }
    
    /* 头部导航 */
    #header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: var(--header-height);
      background: rgba(255,255,255,0.96);
      backdrop-filter: blur(6px);
      box-shadow: var(--shadow-nav);
      z-index: 1000;
      display: flex;
      align-items: center;
      transition: background 0.3s;
    }
    
    .nav-container {
      display: flex;
      justify-content: space-between;
      align-items: center;
      width: 100%;
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 32px;
    }
    
    .logo {
      display: flex;
      align-items: center;
      gap: 10px;
      font-weight: 700;
      font-size: 1.5rem;
      color: var(--primary-deep-green);
      letter-spacing: -0.3px;
    }
    
    .logo-icon {
      display: flex;
      align-items: center;
      justify-content: center;
      width: 36px;
      height: 36px;
      background: var(--primary-deep-green);
      border-radius: 8px;
      position: relative;
      color: white;
    }
    /* 熊猫剪影与竹叶抽象组合 (纯CSS示意) */
    .logo-icon::before {
      content: "🐼";
      font-size: 1.4rem;
      filter: grayscale(0.2);
    }
    .logo-text {
      font-weight: 700;
    }
    
    .nav-links {
      display: flex;
      gap: 32px;
      align-items: center;
      list-style: none;
    }
    
    .nav-links a {
      font-size: 0.95rem;
      font-weight: 500;
      color: var(--text-secondary);
      padding: 8px 0;
      border-bottom: 2px solid transparent;
      transition: color 0.2s, border-color 0.2s;
    }
    
    .nav-links a:hover,
    .nav-links a.active {
      color: var(--primary-deep-green);
      border-bottom-color: var(--primary-deep-green);
    }
    
    .hamburger {
      display: none;
      font-size: 1.6rem;
      cursor: pointer;
      color: var(--primary-deep-green);
      background: none;
      border: none;
    }
    
    /* 主区块间距 */
    section {
      padding: var(--section-gap) 0;
    }
    
    /* Hero 双栏 */
    .hero-grid {
      display: grid;
      grid-template-columns: 5fr 7fr;
      gap: 48px;
      align-items: center;
      min-height: 85vh;
      padding-top: calc(var(--header-height) + 40px);
    }
    
    .hero-left h1 {
      font-size: clamp(2.6rem, 5vw, 3.4rem);
      font-weight: 700;
      line-height: 1.2;
      letter-spacing: -0.02em;
      color: var(--primary-deep-green);
      margin-bottom: 20px;
    }
    
    .hero-sub {
      font-size: 1.1rem;
      color: var(--text-secondary);
      margin-bottom: 32px;
      max-width: 90%;
    }
    
    .cta-group {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    
    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 1rem;
      transition: all var(--transition-base);
      cursor: pointer;
      border: none;
      text-align: center;
    }
    
    .btn-primary {
      background: var(--accent-gold);
      color: white;
      box-shadow: 0 2px 8px rgba(245,166,35,0.25);
    }
    .btn-primary:hover {
      background: var(--accent-gold-hover);
      box-shadow: 0 8px 18px rgba(224,149,21,0.35);
      transform: translateY(-1px);
    }
    
    .btn-secondary {
      background: transparent;
      border: 1.5px solid var(--primary-deep-green);
      color: var(--primary-deep-green);
    }
    .btn-secondary:hover {
      background: rgba(26,60,42,0.08);
    }
    
    .hero-right img {
      border-radius: 16px;
      box-shadow: 0 20px 40px rgba(0,0,0,0.08);
      width: 100%;
      height: auto;
      object-fit: cover;
      aspect-ratio: 4/3;
    }
    
    /* 板块标题 */
    .section-title {
      font-size: 2rem;
      font-weight: 600;
      line-height: 1.3;
      color: var(--primary-deep-green);
      margin-bottom: 12px;
      text-align: center;
    }
    .section-sub {
      font-size: 1rem;
      color: var(--text-secondary);
      text-align: center;
      margin-bottom: 48px;
    }
    
    /* 优势卡片网格 */
    .advantages-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
    }
    .adv-card {
      background: var(--card-bg);
      border: 1px solid var(--card-border);
      border-radius: var(--radius-card);
      padding: 28px 24px;
      transition: all var(--transition-base);
    }
    .adv-card:hover {
      box-shadow: var(--shadow-card-hover);
      transform: translateY(-4px);
    }
    .adv-icon {
      width: 44px;
      height: 44px;
      background: rgba(26,60,42,0.08);
      border-radius: 10px;
      display: flex;
      align-items: center;
      justify-content: center;
      color: var(--primary-deep-green);
      font-size: 1.4rem;
      margin-bottom: 18px;
    }
    .adv-card h3 {
      font-size: 1.25rem;
      font-weight: 600;
      margin-bottom: 8px;
    }
    .adv-card p {
      color: var(--text-secondary);
      font-size: 0.95rem;
      line-height: 1.6;
    }
    
    /* 亮点不规则网格 */
    .highlight-grid {
      display: grid;
      grid-template-columns: 2fr 1fr;
      grid-template-rows: auto auto;
      gap: 24px;
    }
    .highlight-big {
      grid-row: span 2;
      border-radius: var(--radius-card);
      overflow: hidden;
      position: relative;
    }
    .highlight-big img {
      width: 100%;
      height: 100%;
      object-fit: cover;
      aspect-ratio: 16/10;
    }
    .highlight-text-stack {
      display: flex;
      flex-direction: column;
      gap: 24px;
    }
    .text-highlight-item {
      background: var(--card-bg);
      border-radius: var(--radius-list);
      padding: 22px 20px;
      border-left: 4px solid var(--accent-gold);
      box-shadow: var(--shadow-card);
    }
    .stats-row {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .stat-item {
      text-align: center;
      background: var(--card-bg);
      border-radius: var(--radius-list);
      padding: 24px 16px;
    }
    .stat-number {
      font-size: 2.2rem;
      font-weight: 700;
      color: var(--accent-gold);
      font-family: var(--font-english);
    }
    
    /* 案例瀑布流 */
    .cases-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .case-card {
      background: var(--card-bg);
      border-radius: var(--radius-card);
      overflow: hidden;
      transition: all var(--transition-base);
      border: 1px solid var(--card-border);
    }
    .case-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-card-hover);
    }
    .case-img {
      width: 100%;
      aspect-ratio: 16/9;
      object-fit: cover;
      transition: transform 0.4s;
    }
    .case-card:hover .case-img {
      transform: scale(1.05);
    }
    .case-tag {
      display: inline-block;
      background: #f0f0f0;
      color: var(--text-secondary);
      font-size: 0.8rem;
      padding: 4px 12px;
      border-radius: 20px;
      margin: 16px 16px 4px;
    }
    .case-card h3 {
      font-size: 1.1rem;
      margin: 8px 16px 4px;
    }
    .case-card p {
      font-size: 0.9rem;
      color: var(--text-secondary);
      margin: 0 16px 20px;
    }
    
    /* 对比表 */
    .comparison-wrapper {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 32px;
      max-width: 900px;
      margin: 0 auto;
    }
    .compare-col {
      background: var(--card-bg);
      border-radius: var(--radius-card);
      padding: 32px;
      border: 1px solid var(--card-border);
    }
    .compare-col.right {
      border: 2px solid var(--primary-deep-green);
      box-shadow: 0 12px 24px rgba(26,60,42,0.06);
    }
    .compare-col h3 {
      font-size: 1.4rem;
      margin-bottom: 24px;
      display: flex;
      align-items: center;
      gap: 8px;
    }
    .feature-item {
      display: flex;
      align-items: center;
      gap: 12px;
      margin-bottom: 18px;
      color: var(--text-secondary);
    }
    
    /* FAQ */
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
    }
    .faq-item {
      border-bottom: 1px solid var(--card-border);
      padding: 16px 0;
    }
    .faq-question {
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-weight: 600;
      font-size: 1.1rem;
      cursor: pointer;
      color: var(--primary-deep-green);
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.35s ease, padding 0.3s;
      color: var(--text-secondary);
      line-height: 1.8;
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding-top: 12px;
    }
    
    /* 联系CTA */
    .contact-band {
      background: var(--bg-light-grayish);
      border-radius: 24px;
      padding: 56px 32px;
      text-align: center;
    }
    .inline-form {
      display: flex;
      max-width: 480px;
      margin: 28px auto 0;
      border-radius: var(--radius-btn);
      overflow: hidden;
    }
    .inline-form input {
      flex:1;
      height: 48px;
      border: 1px solid #E0DCD5;
      border-right: none;
      padding: 0 20px;
      font-size: 1rem;
      outline: none;
    }
    .inline-form button {
      height: 48px;
      background: var(--accent-gold);
      color: white;
      border: none;
      padding: 0 28px;
      font-weight: 600;
      cursor: pointer;
    }
    
    /* 页脚 */
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
      color: var(--footer-text);
    }
    .footer-brand p {
      margin-top: 12px;
      font-size: 0.9rem;
    }
    
    @media (max-width: 1024px) {
      .advantages-grid { grid-template-columns: repeat(2,1fr); }
      .cases-grid { grid-template-columns: repeat(2,1fr); }
    }
    @media (max-width: 768px) {
      .hamburger { display: block; }
      .nav-links {
        display: none;
        position: absolute;
        top: var(--header-height);
        left: 0;
        width: 100%;
        background: white;
        flex-direction: column;
        padding: 24px;
        gap: 20px;
      }
      .nav-links.active { display: flex; }
      .hero-grid { grid-template-columns: 1fr; }
      .advantages-grid { grid-template-columns: 1fr; }
      .highlight-grid { grid-template-columns: 1fr; }
      .cases-grid { grid-template-columns: 1fr; }
      .comparison-wrapper { grid-template-columns: 1fr; }
      .footer-grid { grid-template-columns: 1fr 1fr; }
    }