/* roulang page: index */
:root {
      --primary-rock: #2C3539;
      --accent-gold: #C5A059;
      --accent-gold-hover: #A8863E;
      --bg-warm: #FAF8F5;
      --bg-card: #FFFFFF;
      --bg-light-gray: #F4F2EF;
      --text-body: #4A4A4A;
      --text-muted: #6B6B6B;
      --text-on-dark: #B0B0B0;
      --border-subtle: rgba(0,0,0,0.05);
      --border-input: #DCD9D4;
      --radius-card: 12px;
      --radius-btn: 6px;
      --radius-tag: 30px;
      --shadow-default: 0 4px 20px rgba(0,0,0,0.04);
      --shadow-hover: 0 12px 40px rgba(0,0,0,0.06);
      --transition-smooth: all 0.25s cubic-bezier(0.25, 0.1, 0.25, 1);
      --font-sans: 'Noto Sans SC', 'Microsoft YaHei', 'PingFang SC', sans-serif;
      --font-inter: 'Inter', sans-serif;
    }
    
    * {
      box-sizing: border-box;
    }
    
    body {
      font-family: var(--font-sans);
      background-color: var(--bg-warm);
      color: var(--text-body);
      line-height: 1.7;
      margin: 0;
      padding: 0;
      -webkit-font-smoothing: antialiased;
    }
    
    h1, h2, h3, h4 {
      font-family: var(--font-sans);
      color: var(--primary-rock);
      margin-top: 0;
    }
    
    a {
      color: var(--accent-gold);
      transition: var(--transition-smooth);
      text-decoration: none;
    }
    a:hover {
      color: var(--accent-gold-hover);
      text-decoration: none;
    }
    
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    
    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding-left: 1.5rem;
      padding-right: 1.5rem;
    }
    
    /* 按钮系统 */
    .btn {
      display: inline-block;
      font-weight: 600;
      border-radius: var(--radius-btn);
      padding: 0.8rem 2.2rem;
      font-size: 1rem;
      transition: var(--transition-smooth);
      border: 2px solid transparent;
      cursor: pointer;
      text-align: center;
      letter-spacing: 0.02em;
    }
    
    .btn-primary {
      background-color: var(--accent-gold);
      color: #FFFFFF;
      border-color: var(--accent-gold);
    }
    .btn-primary:hover {
      background-color: var(--accent-gold-hover);
      border-color: var(--accent-gold-hover);
      color: #FFFFFF;
      transform: translateY(-2px);
      box-shadow: 0 8px 20px rgba(197, 160, 89, 0.25);
    }
    
    .btn-secondary {
      background: transparent;
      border: 2px solid var(--primary-rock);
      color: var(--primary-rock);
    }
    .btn-secondary:hover {
      background: var(--primary-rock);
      color: #FFFFFF;
      transform: translateY(-2px);
    }
    
    .btn-ghost {
      background: transparent;
      border: 2px solid #FFFFFF;
      color: #FFFFFF;
    }
    .btn-ghost:hover {
      background: #FFFFFF;
      color: var(--primary-rock);
      transform: translateY(-2px);
    }
    
    .btn-sm {
      padding: 0.5rem 1.4rem;
      font-size: 0.9rem;
    }
    
    /* 导航 */
    .site-nav {
      background: var(--primary-rock);
      padding: 0 1.5rem;
      height: 75px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      position: sticky;
      top: 0;
      z-index: 99;
      box-shadow: 0 2px 12px rgba(0,0,0,0.08);
    }
    
    .logo {
      font-weight: 700;
      font-size: 1.6rem;
      color: #FFFFFF;
      letter-spacing: 0.03em;
      display: flex;
      align-items: center;
      gap: 0.5rem;
    }
    .logo i {
      color: var(--accent-gold);
      font-size: 1.8rem;
    }
    
    .nav-links {
      display: flex;
      gap: 2.2rem;
      align-items: center;
    }
    .nav-links a {
      color: rgba(255,255,255,0.85);
      font-weight: 400;
      font-size: 0.95rem;
      transition: var(--transition-smooth);
      white-space: nowrap;
    }
    .nav-links a:hover {
      color: var(--accent-gold);
    }
    
    .badge-premium {
      background: var(--accent-gold);
      color: #FFFFFF;
      border-radius: var(--radius-tag);
      padding: 0.25rem 1rem;
      font-size: 0.75rem;
      font-weight: 600;
      letter-spacing: 0.04em;
      margin-left: 0.8rem;
      animation: softPulse 2s infinite;
    }
    
    @keyframes softPulse {
      0% { opacity: 1; }
      50% { opacity: 0.8; }
      100% { opacity: 1; }
    }
    
    .mobile-toggle {
      display: none;
      color: white;
      font-size: 1.8rem;
      cursor: pointer;
    }
    
    /* Hero */
    #hero {
      background: var(--bg-warm);
      padding: 5rem 0;
    }
    .hero-content h1 {
      font-size: 3.7rem;
      font-weight: 700;
      line-height: 1.2;
      letter-spacing: -0.02em;
      color: var(--primary-rock);
      margin-bottom: 1.5rem;
    }
    .hero-content p {
      font-size: 1.2rem;
      color: #5F5F5F;
      max-width: 480px;
      margin-bottom: 2.5rem;
    }
    .hero-image {
      border-radius: 24px;
      overflow: hidden;
      box-shadow: 0 25px 50px -12px rgba(0,0,0,0.15);
      transition: transform 0.4s ease;
    }
    .hero-image:hover {
      transform: scale(1.01);
    }
    
    /* 板块标题 */
    .section-title {
      font-size: 2.6rem;
      font-weight: 600;
      letter-spacing: -0.01em;
      margin-bottom: 1rem;
      color: var(--primary-rock);
    }
    .section-desc {
      font-size: 1.15rem;
      color: var(--text-muted);
      max-width: 650px;
      margin: 0 auto 3rem auto;
    }
    
    /* 卡片 */
    .feature-card {
      background: var(--bg-card);
      border-radius: var(--radius-card);
      padding: 2.2rem 1.8rem;
      box-shadow: var(--shadow-default);
      transition: var(--transition-smooth);
      height: 100%;
      border: 1px solid var(--border-subtle);
    }
    .feature-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-hover);
    }
    .feature-card i {
      color: var(--accent-gold);
      font-size: 2.2rem;
      margin-bottom: 1.2rem;
      transition: transform 0.2s;
    }
    .feature-card:hover i {
      transform: scale(1.08);
      color: var(--accent-gold-hover);
    }
    .feature-card h3 {
      font-size: 1.5rem;
      font-weight: 600;
      margin-bottom: 0.8rem;
    }
    
    /* 图文交错 */
    .img-text-block {
      display: flex;
      align-items: center;
      gap: 3rem;
      margin-bottom: 5rem;
    }
    .img-text-block.reverse {
      flex-direction: row-reverse;
    }
    .img-text-block .text-col {
      flex: 1;
    }
    .img-text-block .img-col {
      flex: 1;
      border-radius: 20px;
      overflow: hidden;
      box-shadow: 0 12px 30px rgba(0,0,0,0.06);
    }
    
    /* 案例卡片 */
    .case-card {
      background: var(--primary-rock);
      color: #FFFFFF;
      border-radius: 18px;
      padding: 2rem;
      height: 100%;
    }
    .case-card .metric {
      font-size: 2.4rem;
      font-weight: 700;
      color: var(--accent-gold);
      font-family: var(--font-inter);
    }
    
    /* FAQ */
    .faq-item {
      border-bottom: 1px solid #E8E5E1;
      padding: 1.2rem 0;
      cursor: pointer;
    }
    .faq-question {
      font-weight: 600;
      font-size: 1.15rem;
      display: flex;
      justify-content: space-between;
      align-items: center;
      color: var(--primary-rock);
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      color: #5A5A5A;
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      margin-top: 0.8rem;
    }
    
    /* 页脚 */
    #footer {
      background: var(--primary-rock);
      color: var(--text-on-dark);
      padding: 4rem 0 1.5rem;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1.2fr;
      gap: 2.5rem;
    }
    .footer-bottom {
      border-top: 1px solid rgba(255,255,255,0.15);
      margin-top: 2.5rem;
      padding-top: 1.5rem;
      text-align: center;
      font-size: 0.9rem;
    }
    
    @media (max-width: 1024px) {
      .hero-content h1 { font-size: 2.8rem; }
      .img-text-block { flex-direction: column; gap: 2rem; }
      .img-text-block.reverse { flex-direction: column; }
      .footer-grid { grid-template-columns: 1fr 1fr; }
    }
    
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .mobile-toggle { display: block; }
      .hero-content h1 { font-size: 2.4rem; }
      .section-title { font-size: 2rem; }
      .footer-grid { grid-template-columns: 1fr; }
    }