/* roulang page: index */
:root {
      --primary: #0A2E1F;
      --primary-soft: rgba(10,46,31,0.08);
      --accent: #E85D04;
      --accent-hover: #D14B00;
      --gold: #F4A261;
      --gold-light: #FFF9F2;
      --bg: #FDFBF7;
      --dark-bg: #0F1A14;
      --text-main: #1E1E1E;
      --text-muted: #5A5A5A;
      --text-light: #B0B8B1;
      --success: #2A9D8F;
      --card-bg: #FFFFFF;
      --card-border: #E8E5DF;
      --font-sans: 'Inter', 'Noto Sans SC', system-ui, -apple-system, sans-serif;
      --radius-card: 20px;
      --radius-btn: 50px;
      --shadow-card: 0 1px 3px rgba(0,0,0,0.04), 0 6px 16px rgba(0,0,0,0.06);
      --shadow-hover: 0 4px 12px rgba(10,46,31,0.12), 0 12px 28px rgba(0,0,0,0.08);
      --transition-smooth: all 0.3s cubic-bezier(0.25, 0.46, 0.45, 0.94);
      --container-max: 1200px;
    }
    
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    
    html {
      scroll-behavior: smooth;
      font-size: 16px;
    }
    
    body {
      font-family: var(--font-sans);
      background-color: var(--bg);
      color: var(--text-main);
      line-height: 1.6;
      -webkit-font-smoothing: antialiased;
      overflow-x: hidden;
    }
    
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    
    a {
      text-decoration: none;
      color: inherit;
      transition: var(--transition-smooth);
    }
    
    button, input, textarea {
      font-family: inherit;
    }
    
    .container {
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 24px;
    }
    
    /* 导航系统 */
    #header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      height: 80px;
      background: transparent;
      transition: background 0.4s ease, height 0.3s ease, box-shadow 0.3s ease;
      display: flex;
      align-items: center;
    }
    
    #header.scrolled {
      background: rgba(255,255,255,0.95);
      backdrop-filter: blur(12px);
      height: 64px;
      box-shadow: 0 2px 12px rgba(0,0,0,0.06);
    }
    
    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
    }
    
    .logo {
      display: flex;
      align-items: center;
      gap: 10px;
      font-weight: 700;
      font-size: 1.5rem;
      color: var(--primary);
      letter-spacing: -0.01em;
    }
    
    .logo-icon {
      width: 38px;
      height: 38px;
      background: var(--primary);
      border-radius: 10px;
      display: flex;
      align-items: center;
      justify-content: center;
      color: white;
      font-size: 22px;
    }
    
    .desktop-nav {
      display: flex;
      align-items: center;
      gap: 32px;
    }
    
    .desktop-nav a {
      font-weight: 500;
      font-size: 1rem;
      color: var(--text-main);
      padding: 8px 0;
      border-bottom: 2px solid transparent;
      transition: var(--transition-smooth);
    }
    
    .desktop-nav a:hover {
      color: var(--accent);
      border-bottom-color: var(--accent);
    }
    
    .btn-nav {
      background: var(--accent);
      color: white !important;
      padding: 12px 28px !important;
      border-radius: var(--radius-btn);
      font-weight: 600;
      letter-spacing: 0.02em;
      box-shadow: 0 2px 8px rgba(232,93,4,0.3);
    }
    
    .btn-nav:hover {
      background: var(--accent-hover);
      transform: scale(1.03);
    }
    
    /* 移动端底部导航 */
    .mobile-bottom-nav {
      display: none;
      position: fixed;
      bottom: 0;
      left: 0;
      width: 100%;
      background: rgba(255,255,255,0.96);
      backdrop-filter: blur(20px);
      border-top: 1px solid #E8E5DF;
      z-index: 999;
      padding: 8px 16px 12px;
      justify-content: space-around;
      align-items: center;
      box-shadow: 0 -4px 12px rgba(0,0,0,0.04);
    }
    
    .mobile-nav-item {
      display: flex;
      flex-direction: column;
      align-items: center;
      font-size: 0.7rem;
      color: var(--text-muted);
      gap: 4px;
      transition: color 0.2s;
    }
    
    .mobile-nav-item i {
      font-size: 1.3rem;
    }
    
    .mobile-nav-item.active {
      color: var(--accent);
    }
    
    .mobile-cta-circle {
      width: 50px;
      height: 50px;
      background: var(--accent);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      color: white;
      font-size: 1.4rem;
      margin-top: -18px;
      box-shadow: 0 4px 14px rgba(232,93,4,0.5);
    }
    
    /* 板块间距 */
    .section {
      padding: 100px 0;
    }
    
    .section-dark {
      background-color: var(--dark-bg);
      color: white;
    }
    
    /* H1/H2 基础 */
    h1 {
      font-weight: 700;
      font-size: clamp(2.5rem, 5vw, 3.5rem);
      line-height: 1.15;
      letter-spacing: -0.02em;
      color: var(--primary);
    }
    
    h2 {
      font-weight: 700;
      font-size: clamp(2rem, 4vw, 2.6rem);
      line-height: 1.2;
      letter-spacing: -0.01em;
      margin-bottom: 16px;
    }
    
    .section-label {
      display: inline-block;
      background: var(--primary-soft);
      color: var(--primary);
      padding: 6px 18px;
      border-radius: 30px;
      font-weight: 600;
      font-size: 0.9rem;
      letter-spacing: 0.04em;
      margin-bottom: 12px;
    }
    
    /* 卡片基础 */
    .card {
      background: var(--card-bg);
      border-radius: var(--radius-card);
      padding: 28px;
      border: 1px solid var(--card-border);
      box-shadow: var(--shadow-card);
      transition: var(--transition-smooth);
    }
    
    .card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-hover);
      border-color: rgba(232,93,4,0.4);
      background: #FFF9F2;
    }
    
    /* 按钮全局 */
    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      font-weight: 600;
      font-size: 1rem;
      letter-spacing: 0.02em;
      border-radius: var(--radius-btn);
      padding: 14px 32px;
      transition: var(--transition-smooth);
      border: none;
      cursor: pointer;
      gap: 8px;
    }
    
    .btn-primary {
      background: var(--accent);
      color: white;
      box-shadow: 0 4px 12px rgba(232,93,4,0.35);
    }
    
    .btn-primary:hover {
      background: var(--accent-hover);
      transform: scale(1.03);
    }
    
    .btn-outline {
      background: transparent;
      border: 2px solid var(--primary);
      color: var(--primary);
    }
    
    .btn-outline:hover {
      background: rgba(10,46,31,0.08);
    }
    
    .btn-light {
      background: transparent;
      border: 2px solid white;
      color: white;
    }
    
    .btn-light:hover {
      background: rgba(255,255,255,0.12);
    }
    
    .btn-text {
      background: transparent;
      color: var(--accent);
      padding: 0;
      font-weight: 600;
      gap: 6px;
      border-radius: 0;
    }
    
    .btn-text i {
      transition: transform 0.2s;
    }
    
    .btn-text:hover i {
      transform: translateX(4px);
    }
    
    /* 网格布局 */
    .grid-3 {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 32px;
    }
    
    .grid-4 {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 28px;
    }
    
    /* 装饰图形 */
    .arc-decoration {
      position: absolute;
      width: 400px;
      height: 400px;
      border: 3px solid rgba(10,46,31,0.08);
      border-radius: 50%;
      z-index: 0;
    }
    
    /* FAQ 手风琴 */
    .faq-item {
      border-bottom: 1px solid #E8E5DF;
      padding: 20px 0;
      cursor: pointer;
    }
    
    .faq-question {
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-weight: 600;
      font-size: 1.2rem;
      color: var(--text-main);
      transition: color 0.2s;
    }
    
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.35s ease;
      background: #F9F8F6;
      border-radius: 12px;
      margin-top: 12px;
      color: var(--text-muted);
    }
    
    .faq-item.open .faq-question {
      color: var(--primary);
    }
    
    .faq-item.open .faq-answer {
      max-height: 200px;
      padding: 20px;
    }
    
    /* 底部 */
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1.5fr 2fr;
      gap: 40px;
    }
    
    @media (max-width: 1024px) {
      .grid-3 { grid-template-columns: repeat(2, 1fr); }
      .grid-4 { grid-template-columns: repeat(2, 1fr); }
      .footer-grid { grid-template-columns: 1fr 1fr; }
      .desktop-nav { display: none; }
      .mobile-bottom-nav { display: flex; }
      #header { background: rgba(255,255,255,0.9); height: 64px; }
      .section { padding: 80px 0; }
    }
    
    @media (max-width: 640px) {
      .container { padding: 0 16px; }
      .grid-3, .grid-4 { grid-template-columns: 1fr; }
      .footer-grid { grid-template-columns: 1fr; }
      .section { padding: 60px 0; }
      .logo { font-size: 1.2rem; }
      .mobile-bottom-nav { display: flex; }
    }
    
    /* hero 背景纹理 */
    .hero-right {
      background: radial-gradient(circle at 20% 30%, rgba(10,46,31,0.08) 0%, transparent 70%);
    }
    
    .testimonial-card {
      background: #FFFBF5;
      border-left: 4px solid var(--accent);
      padding: 24px;
      border-radius: 16px;
    }
    
    .stat-number {
      font-family: 'Inter', sans-serif;
      font-weight: 700;
      font-size: 2.8rem;
      color: var(--accent);
    }