/* roulang page: index */
:root {
      --deep-charcoal: #1a1a1a;
      --antique-gold: #b8860b;
      --warm-porcelain: #fafaf5;
      --pure-white: #ffffff;
      --mid-gray: #555555;
      --light-border: #eaeaea;
      --subtle-shadow: 0 4px 20px rgba(0, 0, 0, 0.04);
      --hover-shadow: 0 12px 30px rgba(0, 0, 0, 0.08);
      --radius-sm: 4px;
      --radius-md: 8px;
      --radius-pill: 50px;
      --transition: all 0.25s ease;
      --section-padding: 6rem 0;
      --font-sans: "Noto Sans SC", "Microsoft YaHei", sans-serif;
      --font-inter: "Inter", sans-serif;
    }
    * {
      box-sizing: border-box;
    }
    body {
      font-family: var(--font-sans);
      background-color: var(--warm-porcelain);
      color: var(--deep-charcoal);
      margin: 0;
      line-height: 1.8;
      font-weight: 400;
      -webkit-font-smoothing: antialiased;
    }
    h1, h2, h3, h4, h5, h6 {
      font-family: var(--font-sans);
      color: var(--deep-charcoal);
    }
    .inter {
      font-family: var(--font-inter);
    }
    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 1.5rem;
    }
    /* 导航栏 */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      background: rgba(250, 250, 245, 0.88);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
      border-bottom: 1px solid var(--light-border);
      z-index: 40;
      padding: 0.75rem 0;
    }
    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
    }
    .logo-area {
      display: flex;
      align-items: center;
      gap: 0.6rem;
    }
    .logo-icon {
      width: 32px;
      height: 32px;
      background: var(--antique-gold);
      mask: url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24"><path d="M12 2L2 7l10 5 10-5-10-5zM2 17l10 5 10-5M2 12l10 5 10-5"/></svg>') center/contain no-repeat;
      background-color: var(--antique-gold);
      display: inline-block;
    }
    .brand-name {
      font-weight: 700;
      font-size: 1.4rem;
      letter-spacing: 1px;
      color: var(--deep-charcoal);
    }
    .nav-links {
      display: flex;
      gap: 2.2rem;
      align-items: center;
    }
    .nav-links a {
      font-weight: 500;
      color: var(--deep-charcoal);
      font-size: 0.95rem;
      padding: 0.25rem 0;
      position: relative;
      white-space: nowrap;
    }
    .nav-links a:hover {
      color: var(--antique-gold);
    }
    .nav-links a.active {
      color: var(--antique-gold);
    }
    .nav-links a.active::after {
      content: '';
      position: absolute;
      bottom: -4px;
      left: 0;
      width: 100%;
      height: 2px;
      background: var(--antique-gold);
      border-radius: 2px;
    }
    .mobile-menu-icon {
      display: none;
      font-size: 1.6rem;
      color: var(--deep-charcoal);
      cursor: pointer;
    }
    /* 板块通用 */
    section {
      padding: var(--section-padding);
    }
    .section-title {
      font-weight: 600;
      font-size: 2.2rem;
      letter-spacing: 2px;
      margin-bottom: 1rem;
      text-align: center;
      position: relative;
      color: var(--deep-charcoal);
    }
    .section-title::after {
      content: '';
      display: block;
      width: 60px;
      height: 2px;
      background: var(--antique-gold);
      margin: 0.8rem auto 2rem;
    }
    .text-muted {
      color: var(--mid-gray);
    }
    /* Hero */
    .hero {
      padding-top: 7rem;
      padding-bottom: 5rem;
      background: var(--warm-porcelain);
    }
    .hero-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 3rem;
      align-items: center;
    }
    .hero-left h1 {
      font-weight: 700;
      font-size: 3.5rem;
      letter-spacing: -0.5px;
      line-height: 1.2;
      margin-bottom: 1.5rem;
    }
    .hero-sub {
      font-size: 1.2rem;
      color: var(--mid-gray);
      margin-bottom: 2rem;
      max-width: 80%;
    }
    .btn-group {
      display: flex;
      gap: 1rem;
      flex-wrap: wrap;
    }
    .btn-primary {
      background: var(--deep-charcoal);
      color: var(--warm-porcelain);
      border: none;
      padding: 12px 32px;
      border-radius: var(--radius-pill);
      font-weight: 600;
      transition: var(--transition);
      display: inline-block;
      text-align: center;
    }
    .btn-primary:hover {
      background: var(--antique-gold);
      color: white;
    }
    .btn-outline {
      background: transparent;
      color: var(--deep-charcoal);
      border: 1px solid var(--deep-charcoal);
      padding: 12px 32px;
      border-radius: var(--radius-pill);
      font-weight: 600;
      transition: var(--transition);
    }
    .btn-outline:hover {
      border-color: var(--antique-gold);
      color: var(--antique-gold);
    }
    .hero-right img {
      border-radius: var(--radius-sm);
      box-shadow: var(--subtle-shadow);
      width: 100%;
      height: auto;
    }
    /* 核心亮点 */
    .highlights-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 2rem;
      margin-top: 2rem;
    }
    .highlight-card {
      background: var(--pure-white);
      border: 1px solid var(--light-border);
      border-radius: var(--radius-md);
      padding: 2rem 1.8rem;
      box-shadow: var(--subtle-shadow);
      transition: var(--transition);
      text-align: center;
    }
    .highlight-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--hover-shadow);
    }
    .highlight-icon {
      font-size: 2.2rem;
      color: var(--antique-gold);
      margin-bottom: 1.2rem;
    }
    .highlight-card h3 {
      font-weight: 600;
      font-size: 1.4rem;
      margin-bottom: 0.75rem;
    }
    /* 方案对比 */
    .compare-table {
      width: 100%;
      border-collapse: collapse;
      background: white;
      border-radius: var(--radius-md);
      overflow: hidden;
      box-shadow: var(--subtle-shadow);
    }
    .compare-table th {
      background: var(--deep-charcoal);
      color: var(--warm-porcelain);
      font-weight: 600;
      padding: 1.2rem;
      text-align: left;
    }
    .compare-table td {
      padding: 1.2rem;
      border-bottom: 1px solid var(--light-border);
    }
    .highlight-col {
      background: rgba(184, 134, 11, 0.05);
      font-weight: 500;
    }
    /* 案例瀑布流 */
    .masonry-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 1.8rem;
      grid-auto-rows: masonry;
    }
    .case-card {
      background: white;
      border-radius: var(--radius-md);
      overflow: hidden;
      box-shadow: var(--subtle-shadow);
      transition: var(--transition);
      break-inside: avoid;
      margin-bottom: 1.8rem;
      border: 1px solid var(--light-border);
    }
    .case-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--hover-shadow);
    }
    .case-img-wrap {
      position: relative;
      overflow: hidden;
    }
    .case-img-wrap img {
      width: 100%;
      display: block;
    }
    .case-overlay {
      position: absolute;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      background: rgba(184, 134, 11, 0.7);
      color: white;
      display: flex;
      align-items: center;
      justify-content: center;
      opacity: 0;
      transition: var(--transition);
      font-weight: 600;
    }
    .case-card:hover .case-overlay {
      opacity: 1;
    }
    .case-info {
      padding: 1.5rem;
    }
    .case-tag {
      font-size: 0.8rem;
      color: var(--antique-gold);
      font-weight: 600;
      margin-bottom: 0.5rem;
    }
    /* FAQ */
    .accordion {
      max-width: 800px;
      margin: 0 auto;
    }
    .accordion-item {
      border-bottom: 1px solid var(--light-border);
    }
    .accordion-title {
      font-weight: 600;
      font-size: 1.1rem;
      padding: 1.2rem 0;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
    }
    .accordion-content {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      background: var(--warm-porcelain);
      padding: 0 1rem;
      color: var(--mid-gray);
    }
    .accordion-item.active .accordion-content {
      max-height: 200px;
      padding: 1rem;
    }
    /* CTA */
    .cta-section {
      background: var(--deep-charcoal);
      color: var(--warm-porcelain);
    }
    .cta-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 2.5rem;
      align-items: center;
    }
    .input-line {
      background: transparent;
      border: none;
      border-bottom: 1px solid #ccc;
      padding: 0.8rem 0;
      width: 100%;
      margin-bottom: 1.5rem;
      color: white;
      outline: none;
      transition: border 0.2s;
    }
    .input-line:focus {
      border-bottom: 1px solid var(--antique-gold);
    }
    /* 页脚 */
    .site-footer {
      background: var(--deep-charcoal);
      color: #ddd;
      padding: 3rem 0 1.5rem;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 2rem;
    }
    .footer-links a {
      display: block;
      color: #ccc;
      margin-bottom: 0.5rem;
    }
    .footer-links a:hover {
      color: var(--antique-gold);
    }
    .social-icons i {
      font-size: 1.4rem;
      margin-right: 1rem;
      color: #ccc;
      transition: var(--transition);
    }
    .social-icons i:hover {
      color: var(--antique-gold);
    }
    @media (max-width: 1024px) {
      .hero-grid, .cta-grid, .footer-grid {
        grid-template-columns: 1fr;
      }
      .masonry-grid {
        grid-template-columns: repeat(2, 1fr);
      }
    }
    @media (max-width: 640px) {
      .nav-links {
        display: none;
        flex-direction: column;
        background: white;
        position: absolute;
        top: 65px;
        left: 0;
        width: 100%;
        padding: 1rem;
      }
      .mobile-menu-icon {
        display: block;
      }
      .highlights-grid, .masonry-grid {
        grid-template-columns: 1fr;
      }
      .hero-left h1 {
        font-size: 2.4rem;
      }
    }