/* roulang page: index */
:root {
      --primary-deep-green: #1B5E20;
      --primary-dark-green: #0D3B0F;
      --accent-red: #C62828;
      --accent-warm-orange: #E65100;
      --bg-warm-white: #FAF7F2;
      --surface-white: #FFFFFF;
      --dark-bg: #263238;
      --badge-amber: #FF6F00;
      --text-dark: #1e1e1e;
      --text-body: #424242;
      --text-muted: #6b6b6b;
      --border-light: #e0dcd5;
      --shadow-sm: 0 4px 20px rgba(0, 0, 0, 0.06);
      --shadow-hover: 0 12px 32px rgba(0, 0, 0, 0.12);
      --radius-xl: 20px;
      --radius-lg: 16px;
      --radius-pill: 30px;
      --font-sans: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", system-ui, -apple-system, sans-serif;
      --font-numbers: "Inter", "Roboto", system-ui;
      --transition-smooth: all 0.3s ease;
    }
    * {
      box-sizing: border-box;
    }
    body {
      font-family: var(--font-sans);
      background-color: var(--bg-warm-white);
      color: var(--text-body);
      line-height: 1.7;
      margin: 0;
      padding-top: 100px; /* 双行导航高度 */
      overflow-x: hidden;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: var(--transition-smooth);
    }
    .container {
      max-width: 1200px;
      padding-left: 20px;
      padding-right: 20px;
    }
    /* 导航双行系统 */
    .navbar-custom {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1050;
      background-color: var(--surface-white);
      box-shadow: 0 2px 8px rgba(0,0,0,0.04);
      transition: var(--transition-smooth);
    }
    .navbar-custom.scrolled {
      box-shadow: 0 4px 18px rgba(0,0,0,0.08);
    }
    .brand-row {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 56px;
      padding: 0 20px;
      border-bottom: 1px solid rgba(0,0,0,0.04);
    }
    .logo-area {
      display: flex;
      align-items: center;
      gap: 8px;
      font-weight: 700;
      font-size: 1.5rem;
      color: var(--primary-deep-green);
      letter-spacing: 0.5px;
    }
    .logo-icon {
      font-size: 1.8rem;
      color: var(--primary-deep-green);
    }
    .btn-consult {
      background: linear-gradient(135deg, var(--accent-red) 0%, var(--accent-warm-orange) 100%);
      border: none;
      color: white;
      font-weight: 600;
      padding: 8px 22px;
      border-radius: var(--radius-pill);
      font-size: 0.9rem;
      letter-spacing: 0.3px;
      transition: var(--transition-smooth);
      box-shadow: 0 4px 10px rgba(198,40,40,0.25);
      white-space: nowrap;
    }
    .btn-consult:hover {
      background: linear-gradient(135deg, #b71c1c 0%, #d84315 100%);
      transform: scale(1.03);
      color: white;
      box-shadow: 0 8px 18px rgba(198,40,40,0.35);
    }
    .channel-row {
      display: flex;
      align-items: center;
      justify-content: center;
      height: 44px;
      padding: 0 20px;
      overflow-x: auto;
      white-space: nowrap;
      gap: 28px;
      background-color: var(--surface-white);
    }
    .channel-link {
      font-size: 0.9rem;
      font-weight: 500;
      color: var(--primary-deep-green);
      position: relative;
      padding: 4px 0;
      transition: var(--transition-smooth);
      display: inline-block;
    }
    .channel-link::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 50%;
      width: 0;
      height: 2px;
      background-color: var(--accent-red);
      transition: width 0.25s ease, left 0.25s ease;
    }
    .channel-link:hover::after,
    .channel-link.active::after {
      width: 100%;
      left: 0;
    }
    .channel-link.active {
      font-weight: 700;
    }
    /* 区块间距 */
    section {
      padding: 80px 0;
      scroll-margin-top: 100px;
    }
    .section-title {
      font-size: 2rem;
      font-weight: 700;
      color: var(--text-dark);
      margin-bottom: 1.2rem;
      letter-spacing: -0.3px;
    }
    .section-sub {
      color: var(--text-muted);
      font-size: 1.1rem;
      margin-bottom: 3rem;
    }
    /* Hero 区域 */
    #hero {
      padding-top: 40px;
      padding-bottom: 60px;
    }
    .hero-title {
      font-size: 2.8rem;
      font-weight: 800;
      line-height: 1.2;
      color: var(--primary-deep-green);
    }
    .hero-sub {
      font-size: 1.2rem;
      color: var(--text-body);
      margin: 1.5rem 0 2rem;
    }
    .btn-primary-gradient {
      background: linear-gradient(135deg, var(--accent-red) 0%, var(--accent-warm-orange) 100%);
      border: none;
      color: white;
      font-weight: 600;
      padding: 12px 32px;
      border-radius: var(--radius-pill);
      transition: var(--transition-smooth);
      box-shadow: 0 6px 16px rgba(198,40,40,0.3);
    }
    .btn-primary-gradient:hover {
      background: linear-gradient(135deg, #b71c1c, #d84315);
      transform: scale(1.04);
      color: white;
    }
    .btn-outline-green {
      border: 2px solid var(--primary-deep-green);
      color: var(--primary-deep-green);
      background: transparent;
      font-weight: 600;
      padding: 12px 32px;
      border-radius: var(--radius-pill);
      transition: var(--transition-smooth);
    }
    .btn-outline-green:hover {
      background: rgba(27,94,32,0.08);
      border-color: var(--primary-dark-green);
      color: var(--primary-dark-green);
    }
    .hero-cards-stack {
      position: relative;
      height: 380px;
      width: 100%;
      max-width: 400px;
      margin: 0 auto;
    }
    .stack-card {
      position: absolute;
      width: 260px;
      height: 340px;
      border-radius: var(--radius-xl);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
      transition: var(--transition-smooth);
      background-size: cover;
      background-position: center;
    }
    .stack-card:nth-child(1) {
      transform: rotate(-6deg);
      z-index: 1;
      left: 10px;
      top: 20px;
    }
    .stack-card:nth-child(2) {
      transform: rotate(0deg);
      z-index: 2;
      left: 60px;
      top: 0;
    }
    .stack-card:nth-child(3) {
      transform: rotate(8deg);
      z-index: 3;
      left: 110px;
      top: 25px;
    }
    /* 卡片通用 */
    .card-custom {
      background: var(--surface-white);
      border-radius: var(--radius-xl);
      padding: 28px;
      box-shadow: var(--shadow-sm);
      transition: var(--transition-smooth);
      height: 100%;
      border: 1px solid rgba(0,0,0,0.02);
    }
    .card-custom:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
    }
    .badge-amber {
      background-color: var(--badge-amber);
      color: white;
      font-weight: 600;
      font-size: 0.8rem;
      padding: 4px 12px;
      border-radius: 12px;
      display: inline-flex;
      align-items: center;
      gap: 4px;
      font-family: var(--font-numbers);
    }
    /* 产品卡片 Masonry 风格 */
    .masonry-card {
      border-radius: var(--radius-lg);
      overflow: hidden;
      background: white;
      box-shadow: var(--shadow-sm);
      transition: var(--transition-smooth);
      margin-bottom: 24px;
    }
    .masonry-card:hover {
      transform: translateY(-5px);
      box-shadow: var(--shadow-hover);
    }
    .masonry-img {
      height: 200px;
      object-fit: cover;
      width: 100%;
    }
    /* 对比表 */
    .compare-table {
      background: white;
      border-radius: var(--radius-xl);
      padding: 28px;
      box-shadow: var(--shadow-sm);
    }
    .vs-badge {
      background: var(--accent-red);
      color: white;
      font-weight: 700;
      border-radius: 50%;
      width: 48px;
      height: 48px;
      display: flex;
      align-items: center;
      justify-content: center;
    }
    /* FAQ */
    .accordion-button:not(.collapsed) {
      background-color: rgba(27,94,32,0.05);
      color: var(--primary-deep-green);
      font-weight: 600;
      border-left: 4px solid var(--accent-red);
    }
    .accordion-button {
      font-weight: 500;
      background: white;
      box-shadow: none;
    }
    .faq-icon {
      margin-right: 12px;
      color: var(--accent-red);
      font-size: 1.2rem;
    }
    /* CTA 横幅 */
    .cta-banner {
      background: linear-gradient(135deg, #1B5E20 0%, #0D3B0F 100%);
      border-radius: 28px;
      padding: 60px 40px;
      color: white;
    }
    /* 页脚 */
    footer {
      background-color: var(--dark-bg);
      color: #cfd8dc;
      padding: 50px 0 20px;
    }
    footer a {
      color: #b0bec5;
    }
    footer a:hover {
      color: var(--accent-red);
    }
    @media (max-width: 768px) {
      .hero-title {
        font-size: 2.2rem;
      }
      .channel-row {
        justify-content: flex-start;
        gap: 20px;
      }
      .hero-cards-stack {
        height: 280px;
        max-width: 300px;
      }
      .stack-card {
        width: 180px;
        height: 240px;
      }
    }