/* roulang page: index */
:root {
      /* 核心品牌色调 */
      --primary-terra: #C75B2E;
      --deep-forest: #1C3D3A;
      --off-white-papyrus: #F4E9D8;
      --golden-saffron: #E8A317;
      --golden-dark: #C78A14;
      
      /* 文字系统 */
      --text-primary: #1E1E1E;
      --text-secondary: #5A5A5A;
      --text-muted: #8C8C8C;
      --text-on-dark: #F4E9D8;
      
      /* 背景与边框 */
      --border-subtle: #E0D6C8;
      --card-bg: #FFFFFF;
      --deep-bg: #1C3D3A;
      
      /* 圆角与阴影 */
      --radius-card: 12px;
      --radius-btn: 8px;
      --shadow-hover: 0 12px 28px rgba(28, 61, 58, 0.12);
      --nav-blur: rgba(244, 233, 216, 0.92);
      --border-card: 1px solid #E0D6C8;
      
      /* 间距 */
      --section-gap: 120px;
      --container-max: 1280px;
      --grid-gap: 24px;
      
      /* 字体比例 */
      --font-serif: 'Noto Serif SC', 'Source Han Serif', serif;
      --font-sans: 'Inter', system-ui, -apple-system, 'Noto Sans SC', sans-serif;
    }

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

    body {
      font-family: var(--font-sans);
      background-color: var(--off-white-papyrus);
      color: var(--text-primary);
      line-height: 1.75;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
      padding-top: 0;
    }

    /* 容器与导航 */
    .container {
      max-width: var(--container-max);
      margin-left: auto;
      margin-right: auto;
      padding-left: 24px;
      padding-right: 24px;
    }

    /* 主导航：白底平台 + 滚动模糊 */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 72px;
      display: flex;
      align-items: center;
      justify-content: center;
      background: transparent;
      transition: background 0.3s ease, box-shadow 0.3s ease;
      z-index: 99;
      backdrop-filter: blur(0px);
    }

    .site-header.scrolled {
      background: rgba(244, 233, 216, 0.92);
      backdrop-filter: blur(12px);
      box-shadow: 0 1px 8px rgba(0,0,0,0.05);
    }

    .nav-container {
      width: 100%;
      max-width: var(--container-max);
      display: flex;
      align-items: center;
      justify-content: space-between;
      padding: 0 24px;
    }

    .logo {
      display: flex;
      align-items: baseline;
      gap: 8px;
      text-decoration: none;
    }
    .logo-text {
      font-family: var(--font-serif);
      font-weight: 700;
      font-size: 22px;
      color: var(--deep-forest);
      letter-spacing: 1px;
    }
    .logo-domain {
      font-family: var(--font-sans);
      font-size: 12px;
      font-weight: 500;
      color: var(--primary-terra);
      background: rgba(199, 91, 46, 0.08);
      padding: 2px 8px;
      border-radius: 20px;
    }

    .nav-links {
      display: flex;
      align-items: center;
      gap: 32px;
    }
    .nav-links a {
      font-size: 15px;
      font-weight: 500;
      color: var(--text-primary);
      text-decoration: none;
      position: relative;
      padding: 8px 0;
      transition: color 0.25s;
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 50%;
      transform: translateX(-50%) scaleX(0);
      width: 60%;
      height: 2px;
      background: var(--primary-terra);
      transition: transform 0.25s ease;
    }
    .nav-links a:hover {
      color: var(--primary-terra);
    }
    .nav-links a:hover::after {
      transform: translateX(-50%) scaleX(1);
    }

    .btn-primary {
      background: var(--golden-saffron);
      color: var(--deep-forest);
      font-weight: 600;
      padding: 10px 22px;
      border-radius: var(--radius-btn);
      text-decoration: none;
      transition: 0.25s ease;
      display: inline-flex;
      align-items: center;
      gap: 6px;
      border: none;
      cursor: pointer;
      font-size: 15px;
      line-height: 1.4;
    }
    .btn-primary:hover {
      background: var(--golden-dark);
      transform: scale(1.02);
      box-shadow: 0 8px 18px rgba(200, 135, 20, 0.25);
    }

    .btn-secondary {
      background: transparent;
      border: 2px solid var(--deep-forest);
      color: var(--deep-forest);
      font-weight: 600;
      padding: 10px 22px;
      border-radius: var(--radius-btn);
      text-decoration: none;
      transition: 0.25s ease;
    }
    .btn-secondary:hover {
      background: var(--deep-forest);
      color: white;
      border-color: var(--deep-forest);
    }

    /* 移动菜单汉堡按钮 */
    .burger {
      display: none;
      font-size: 28px;
      background: none;
      border: none;
      color: var(--deep-forest);
      cursor: pointer;
    }

    @media (max-width: 1024px) {
      .nav-links {
        gap: 20px;
      }
      .btn-primary.nav-cta {
        padding: 8px 18px;
        font-size: 14px;
      }
    }

    @media (max-width: 768px) {
      .nav-links.desktop-nav {
        display: none;
      }
      .burger {
        display: block;
      }
      .mobile-menu {
        display: none;
        position: fixed;
        top: 72px;
        left: 0;
        width: 100%;
        background: rgba(28, 61, 58, 0.98);
        backdrop-filter: blur(24px);
        flex-direction: column;
        padding: 40px 24px;
        gap: 28px;
        z-index: 999;
      }
      .mobile-menu.active {
        display: flex;
      }
      .mobile-menu a {
        color: var(--off-white-papyrus);
        font-size: 20px;
        font-weight: 500;
        text-decoration: none;
        border-bottom: 1px solid rgba(255,255,255,0.12);
        padding-bottom: 12px;
      }
    }

    /* 底部胶囊导航 (小屏) 仅在 mobile 层叠展示，与 header 移动按钮共存 */
    .mobile-bottom-nav {
      display: none;
    }
    @media (max-width: 768px) {
      .mobile-bottom-nav {
        display: flex;
        position: fixed;
        bottom: 16px;
        left: 16px;
        right: 16px;
        background: rgba(28, 61, 58, 0.92);
        backdrop-filter: blur(20px);
        border-radius: 48px;
        padding: 8px 20px;
        justify-content: space-around;
        align-items: center;
        z-index: 99;
        box-shadow: 0 8px 24px rgba(0,0,0,0.2);
      }
      .mobile-bottom-nav a {
        color: var(--off-white-papyrus);
        font-size: 18px;
        text-align: center;
        flex: 1;
        text-decoration: none;
      }
      .mobile-bottom-nav .center-cta {
        background: var(--golden-saffron);
        border-radius: 40px;
        padding: 10px 18px;
        color: var(--deep-forest);
        font-weight: 700;
      }
    }

    /* 通用区块样式 */
    section {
      padding: 80px 0;
    }
    .section-title {
      font-family: var(--font-serif);
      font-size: 36px;
      font-weight: 600;
      color: var(--deep-forest);
      margin-bottom: 16px;
    }
    @media (max-width: 640px) {
      .section-title { font-size: 28px; }
    }

    /* Hero 双栏 */
    .hero {
      padding-top: 140px;
      display: flex;
      align-items: center;
      gap: 48px;
    }
    .hero-left {
      flex: 1;
    }
    .hero-h1 {
      font-family: var(--font-serif);
      font-size: 48px;
      font-weight: 700;
      color: var(--deep-forest);
      line-height: 1.25;
      margin-bottom: 24px;
    }
    .hero-sub {
      font-size: 18px;
      color: var(--text-secondary);
      margin-bottom: 32px;
    }
    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .hero-right {
      flex: 1;
      position: relative;
      border-radius: var(--radius-card);
      overflow: hidden;
    }
    .hero-right img {
      width: 100%;
      height: auto;
      display: block;
      border-radius: var(--radius-card);
    }
    .hero-overlay {
      position: absolute;
      bottom: 0;
      left: 0;
      width: 100%;
      height: 40%;
      background: linear-gradient(to top, rgba(199, 91, 46, 0.55), transparent);
    }

    /* 核心亮点网格 */
    .features-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: var(--grid-gap);
      margin-top: 32px;
    }
    .feature-item {
      padding: 32px;
      background: transparent;
      border-radius: var(--radius-card);
      transition: 0.3s ease;
    }
    .feature-item:hover {
      background: var(--card-bg);
      transform: translateY(-6px);
    }

    /* 案例瀑布流 */
    .case-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .case-card {
      background: var(--card-bg);
      border: var(--border-card);
      border-radius: var(--radius-card);
      overflow: hidden;
      transition: 0.3s;
    }
    .case-card:hover {
      border-color: var(--primary-terra);
      transform: translateY(-6px);
      box-shadow: var(--shadow-hover);
    }

    /* 方案对比 */
    .compare-row {
      display: flex;
      gap: 24px;
    }
    .compare-col {
      flex:1; padding:32px; border-radius:12px;
    }

    /* 数据条 */
    .stats-bar {
      display: flex;
      justify-content: space-around;
      text-align: center;
      background: rgba(199,91,46,0.05);
      padding: 40px 0;
      border-radius: 12px;
    }

    /* FAQ 双列布局省略部分，直接定义 */

    footer {
      background: var(--deep-bg);
      color: var(--off-white-papyrus);
      padding: 60px 0 30px;
    }

    @media (max-width: 768px) {
      .features-grid, .case-grid { grid-template-columns: 1fr; }
      .hero { flex-direction: column; }
    }
    @media (min-width: 640px) and (max-width: 1024px) {
      .case-grid { grid-template-columns: 1fr 1fr; }
    }