/* roulang page: index */
:root {
      --primary: #0B3B2F;
      --accent: #C8F526;
      --bg-page: #F5F7F6;
      --bg-card: #FFFFFF;
      --text-heading: #1E1E1E;
      --text-body: #5C6B63;
      --border-subtle: #DCE3DF;
      --bg-dark: #0A1F1A;
      --text-light: #BCC9C4;
      --shadow-card: 0 2px 12px rgba(11,59,47,0.06);
      --shadow-elevated: 0 8px 24px rgba(11,59,47,0.12);
      --radius-card: 12px;
      --radius-data: 16px;
      --radius-btn: 8px;
      --font-sans: "PingFang SC", "Microsoft YaHei", "Noto Sans SC", sans-serif;
      --font-mono: "Inter", "SF Pro Display", sans-serif;
      --transition: all 0.25s ease;
    }

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

    body {
      font-family: var(--font-sans);
      background-color: var(--bg-page);
      color: var(--text-body);
      line-height: 1.75;
      -webkit-font-smoothing: antialiased;
    }

    img {
      max-width: 100%;
      height: auto;
      display: block;
    }

    a {
      text-decoration: none;
      color: inherit;
      transition: var(--transition);
    }

    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }

    /* 顶部信息条 */
    .top-bar {
      background-color: var(--bg-dark);
      color: var(--border-subtle);
      font-size: 0.85rem;
      height: 36px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      padding: 0 24px;
      letter-spacing: 0.02em;
    }
    .top-bar a {
      color: var(--accent);
      font-weight: 600;
    }
    @media (max-width: 640px) {
      .top-bar span:last-child {
        display: none;
      }
    }

    /* 主导航 */
    .main-nav {
      background: var(--bg-card);
      border-bottom: 1px solid var(--border-subtle);
      position: sticky;
      top: 0;
      z-index: 50;
      padding: 0 24px;
      height: 64px;
      display: flex;
      align-items: center;
      justify-content: space-between;
    }
    .logo {
      font-family: var(--font-mono);
      font-weight: 800;
      font-size: 1.6rem;
      color: var(--primary);
      letter-spacing: -0.02em;
      display: flex;
      align-items: center;
      gap: 8px;
    }
    .logo svg {
      width: 36px;
      height: 36px;
      fill: var(--primary);
    }
    .nav-links {
      display: flex;
      gap: 2rem;
      font-weight: 600;
      color: var(--text-heading);
    }
    .nav-links a {
      position: relative;
      padding: 4px 0;
    }
    .nav-links a::after {
      content: "";
      position: absolute;
      left: 0;
      bottom: 0;
      width: 0;
      height: 2px;
      background: var(--accent);
      transition: width 0.25s ease;
    }
    .nav-links a:hover::after {
      width: 100%;
    }
    .nav-links a:hover {
      color: var(--primary);
    }
    .hamburger {
      display: none;
      background: none;
      border: none;
      font-size: 1.8rem;
      cursor: pointer;
      color: var(--primary);
    }
    @media (max-width: 1024px) {
      .nav-links {
        display: none;
      }
      .hamburger {
        display: block;
      }
    }
    .mobile-menu {
      position: absolute;
      top: 64px;
      left: 0;
      width: 100%;
      background: var(--bg-card);
      flex-direction: column;
      gap: 1.2rem;
      padding: 24px;
      border-bottom: 1px solid var(--border-subtle);
      box-shadow: var(--shadow-elevated);
      display: none;
    }
    .mobile-menu.active {
      display: flex;
    }

    /* Hero */
    #hero {
      background: linear-gradient(135deg, #0B3B2F 0%, #0A1F1A 100%);
      background-image: url('data:image/svg+xml,%3Csvg width="60" height="60" xmlns="http://www.w3.org/2000/svg"%3E%3Cpath d="M30 5 L55 20 L55 45 L30 60 L5 45 L5 20 Z" fill="none" stroke="%23FFFFFF" stroke-opacity="0.05" /%3E%3C/svg%3E'), linear-gradient(135deg, #0B3B2F 0%, #0A1F1A 100%);
      min-height: 75vh;
      display: flex;
      align-items: center;
      padding: 60px 0;
    }
    .hero-grid {
      display: flex;
      align-items: center;
      gap: 3rem;
    }
    .hero-text {
      flex: 1 1 55%;
    }
    .hero-badge {
      display: inline-block;
      background: rgba(200,245,38,0.12);
      color: var(--accent);
      font-size: 0.8rem;
      font-weight: 600;
      letter-spacing: 0.1em;
      padding: 6px 16px;
      border-radius: 20px;
      margin-bottom: 1.2rem;
      border: 1px solid rgba(200,245,38,0.3);
    }
    h1 {
      font-family: var(--font-sans);
      font-size: clamp(2.5rem, 5vw, 4rem);
      font-weight: 800;
      letter-spacing: -0.02em;
      line-height: 1.15;
      color: white;
      margin-bottom: 1.5rem;
    }
    .hero-desc {
      color: var(--text-light);
      font-size: 1.1rem;
      max-width: 480px;
      margin-bottom: 2rem;
    }
    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .btn-primary {
      background: var(--accent);
      color: var(--primary);
      font-weight: 700;
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      border: none;
      cursor: pointer;
      transition: var(--transition);
      box-shadow: 0 4px 12px rgba(200,245,38,0.25);
      display: inline-block;
    }
    .btn-primary:hover {
      box-shadow: 0 0 20px rgba(200,245,38,0.5);
      filter: brightness(1.1);
    }
    .btn-outline {
      background: transparent;
      border: 1.5px solid var(--primary);
      color: white;
      font-weight: 600;
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      transition: var(--transition);
      display: inline-block;
    }
    .btn-outline:hover {
      background: var(--primary);
      border-color: var(--primary);
    }
    .hero-image {
      flex: 1 1 45%;
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      border-radius: 20px;
      min-height: 320px;
      filter: brightness(0.9) saturate(0.8);
      box-shadow: 0 16px 32px rgba(0,0,0,0.3);
    }
    @media (max-width: 768px) {
      .hero-grid {
        flex-direction: column;
      }
      .hero-image {
        width: 100%;
        min-height: 240px;
      }
    }

    /* 通用板块 */
    section {
      padding: 80px 0;
    }
    h2 {
      font-size: clamp(1.8rem, 3.5vw, 2.5rem);
      font-weight: 700;
      letter-spacing: -0.01em;
      color: var(--text-heading);
      margin-bottom: 12px;
    }
    .section-subtitle {
      color: var(--text-body);
      margin-bottom: 48px;
      font-size: 1.05rem;
    }

    /* 数据看板 */
    .data-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .data-card {
      background: #F0F4F2;
      border-radius: var(--radius-data);
      padding: 28px;
      position: relative;
      transition: var(--transition);
    }
    .data-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-elevated);
    }
    .data-number {
      font-family: var(--font-mono);
      font-size: 2.5rem;
      font-weight: 700;
      color: var(--primary);
      letter-spacing: -0.03em;
    }
    .data-label {
      margin-top: 8px;
      color: var(--text-body);
    }
    .trend-icon {
      position: absolute;
      right: 20px;
      bottom: 20px;
      color: var(--accent);
      font-size: 1.4rem;
    }

    /* 产品矩阵 */
    .product-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .product-card {
      background: var(--bg-card);
      border-radius: var(--radius-card);
      padding: 24px;
      box-shadow: var(--shadow-card);
      transition: var(--transition);
    }
    .product-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-elevated);
    }
    .product-icon {
      width: 100%;
      height: 140px;
      object-fit: cover;
      border-radius: 8px;
      margin-bottom: 16px;
      background: #F0F4F2;
    }
    .product-card h3 {
      font-size: 1.25rem;
      font-weight: 600;
      color: var(--primary);
    }
    .product-desc {
      margin: 8px 0;
    }
    .product-base {
      border-top: 1px solid var(--border-subtle);
      padding-top: 12px;
      font-size: 0.9rem;
      color: var(--text-body);
    }

    /* 对比条 */
    .comparison-bg {
      background: #F5F7F6;
    }
    .comparison-item {
      display: flex;
      align-items: center;
      gap: 20px;
      margin-bottom: 28px;
    }
    .comparison-label {
      width: 120px;
      font-weight: 600;
      color: var(--text-heading);
    }
    .comparison-bars {
      flex: 1;
    }
    .bar-old {
      height: 10px;
      background: #DCE3DF;
      border-radius: 5px;
      margin-bottom: 6px;
      position: relative;
      width: 70%;
    }
    .bar-z6mg {
      height: 10px;
      background: var(--primary);
      border-radius: 5px;
      width: 95%;
      position: relative;
    }
    .bar-value {
      font-family: var(--font-mono);
      font-size: 0.9rem;
      font-weight: 600;
      margin-left: 12px;
      color: var(--primary);
    }

    /* FAQ */
    .faq-item {
      border-bottom: 1px solid var(--border-subtle);
      padding: 16px 0;
    }
    .faq-question {
      font-weight: 700;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      color: var(--text-heading);
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.35s ease;
      background: #f9fbfa;
      padding: 0 12px;
      margin-top: 8px;
      border-radius: 6px;
    }
    .faq-item.open .faq-answer {
      max-height: 200px;
      padding: 12px;
    }

    /* CTA */
    .cta-section {
      background: var(--primary);
      color: white;
    }
    .cta-form {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
      margin-top: 32px;
    }
    .cta-form input, .cta-form select {
      flex: 1 1 200px;
      padding: 12px 16px;
      border-radius: var(--radius-btn);
      border: 1px solid var(--border-subtle);
      background: white;
      font-family: var(--font-sans);
    }
    .cta-form input:focus, .cta-form select:focus {
      border-color: var(--accent);
      outline: none;
    }
    .btn-submit {
      background: var(--accent);
      color: var(--primary);
      font-weight: 700;
      padding: 12px 28px;
      border: none;
      border-radius: var(--radius-btn);
      cursor: pointer;
    }

    /* Footer */
    .footer {
      background: var(--bg-dark);
      color: var(--text-light);
      padding: 48px 0 24px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 32px;
    }
    .footer a {
      color: var(--text-light);
    }
    @media (max-width: 768px) {
      .data-grid, .product-grid, .footer-grid {
        grid-template-columns: 1fr;
      }
      .comparison-item {
        flex-direction: column;
        align-items: flex-start;
      }
    }