/* roulang page: index */
:root {
      --primary: #C87A2C;
      --secondary: #2B3A42;
      --bg: #FAF8F5;
      --accent: #D4A24E;
      --text-heading: #1E1E1E;
      --text-body: #4A4A4A;
      --text-muted: #8C7B6B;
      --border-light: #E8E0D5;
      --card-bg: #FFFFFF;
      --shadow-sm: 0 4px 20px rgba(0,0,0,0.04);
      --shadow-hover: 0 8px 30px rgba(0,0,0,0.08);
      --radius-card: 12px;
      --radius-btn: 40px;
      --radius-input: 8px;
      --transition: 0.3s ease;
      --container-max: 1200px;
      --nav-height: 72px;
      --section-gap: 100px;
    }

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

    body {
      font-family: 'Noto Sans SC', 'Inter', system-ui, -apple-system, sans-serif;
      font-weight: 400;
      line-height: 1.8;
      color: var(--text-body);
      background-color: var(--bg);
      -webkit-font-smoothing: antialiased;
      scroll-behavior: smooth;
    }

    h1, h2, h3, .serif-title {
      font-family: 'Noto Serif SC', 'Times New Roman', serif;
      font-weight: 700;
      color: var(--text-heading);
      letter-spacing: -0.02em;
    }

    h1 { font-size: 48px; line-height: 1.2; }
    h2 { font-size: 36px; line-height: 1.3; margin-bottom: 1.5rem; position: relative; display: inline-block; }
    h3 { font-size: 22px; line-height: 1.4; }
    p, li { font-size: 16px; color: var(--text-body); }

    a {
      color: var(--primary);
      text-decoration: none;
      transition: color var(--transition);
    }
    a:hover { color: var(--accent); }

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

    .container {
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 24px;
    }

    /* 导航 - 透明玻璃沉浸 */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: var(--nav-height);
      background: rgba(250,248,245,0.75);
      backdrop-filter: blur(16px);
      -webkit-backdrop-filter: blur(16px);
      border-bottom: 1px solid var(--border-light);
      z-index: 100;
      display: flex;
      align-items: center;
      transition: background 0.3s, box-shadow 0.3s;
    }

    .site-header.scrolled {
      background: rgba(250,248,245,0.95);
      box-shadow: 0 2px 16px rgba(0,0,0,0.06);
    }

    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
    }

    .logo {
      font-family: 'Noto Serif SC', serif;
      font-weight: 700;
      font-size: 24px;
      color: var(--primary);
      letter-spacing: 1px;
      display: flex;
      align-items: center;
      gap: 8px;
    }
    .logo i {
      font-size: 28px;
      color: var(--accent);
    }

    .nav-links {
      display: flex;
      gap: 40px;
      align-items: center;
    }
    .nav-links a {
      color: var(--secondary);
      font-weight: 500;
      font-size: 16px;
      padding: 8px 0;
      position: relative;
      transition: color var(--transition);
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--primary);
      transition: width var(--transition);
    }
    .nav-links a:hover { color: var(--primary); }
    .nav-links a:hover::after { width: 100%; }

    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      font-weight: 600;
      border-radius: var(--radius-btn);
      padding: 12px 28px;
      cursor: pointer;
      transition: all var(--transition);
      border: 2px solid transparent;
      font-size: 16px;
      background: transparent;
      text-align: center;
    }
    .btn-primary {
      background: var(--primary);
      color: white;
      border-color: var(--primary);
    }
    .btn-primary:hover {
      background: var(--secondary);
      border-color: var(--secondary);
      color: white;
      transform: translateY(-2px);
    }
    .btn-outline {
      border: 2px solid var(--secondary);
      color: var(--secondary);
      background: transparent;
    }
    .btn-outline:hover {
      background: var(--secondary);
      color: white;
      transform: translateY(-2px);
    }
    .btn-small {
      padding: 8px 20px;
      font-size: 14px;
    }

    .mobile-toggle {
      display: none;
      background: none;
      border: none;
      font-size: 28px;
      color: var(--secondary);
      cursor: pointer;
    }

    /* Hero */
    #hero {
      min-height: 100vh;
      display: flex;
      align-items: center;
      background: var(--bg);
      background-image: radial-gradient(circle at 20% 30%, rgba(200,122,44,0.03) 0%, transparent 50%);
      padding-top: var(--nav-height);
    }
    .hero-grid {
      display: grid;
      grid-template-columns: 1.1fr 0.9fr;
      gap: 60px;
      align-items: center;
    }
    .hero-text h1 {
      margin-bottom: 20px;
      color: var(--text-heading);
    }
    .hero-sub {
      font-size: 18px;
      color: var(--secondary);
      margin-bottom: 32px;
      line-height: 1.7;
    }
    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .hero-image {
      position: relative;
    }
    .hero-image img {
      border-radius: 20px;
      box-shadow: 0 20px 40px rgba(0,0,0,0.08);
      width: 100%;
      height: auto;
    }
    .hero-image::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 100%;
      height: 30%;
      background: linear-gradient(to top, rgba(200,122,44,0.12), transparent);
      border-radius: 0 0 20px 20px;
    }

    /* 区块通用 */
    section {
      padding: var(--section-gap) 0;
    }
    .section-title {
      margin-bottom: 60px;
    }
    .section-title h2 {
      border-left: 6px solid var(--primary);
      padding-left: 20px;
      display: inline-block;
    }

    /* 优势 - 不对称网格 */
    .advantages-grid {
      display: grid;
      grid-template-columns: 2fr 1fr;
      gap: 24px;
    }
    .adv-main-card {
      background: var(--card-bg);
      border-radius: var(--radius-card);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
      border: 1px solid var(--border-light);
      display: flex;
      flex-direction: column;
    }
    .adv-main-card img {
      width: 100%;
      height: 260px;
      object-fit: cover;
    }
    .adv-content {
      padding: 28px 32px;
    }
    .adv-small-cards {
      display: flex;
      flex-direction: column;
      gap: 24px;
    }
    .adv-small {
      background: #F5F0EA;
      border-radius: var(--radius-card);
      padding: 28px;
      box-shadow: var(--shadow-sm);
      border: 1px solid var(--border-light);
    }
    .adv-small i {
      font-size: 32px;
      color: var(--primary);
      margin-bottom: 12px;
    }

    /* 亮点网格 */
    .highlight-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 20px;
    }
    .highlight-item {
      position: relative;
      border-radius: var(--radius-card);
      overflow: hidden;
      min-height: 280px;
      background-size: cover;
      background-position: center;
      display: flex;
      align-items: flex-end;
      padding: 24px;
      color: white;
    }
    .highlight-item.large {
      grid-row: span 2;
      min-height: 580px;
    }
    .highlight-overlay {
      position: absolute;
      inset: 0;
      background: linear-gradient(to top, rgba(43,58,66,0.85) 20%, rgba(200,122,44,0.3) 80%);
      z-index: 1;
    }
    .highlight-text {
      position: relative;
      z-index: 2;
    }
    .highlight-text h3 {
      color: white;
      margin-bottom: 8px;
    }
    .tag {
      display: inline-block;
      background: var(--secondary);
      color: white;
      padding: 4px 14px;
      border-radius: 20px;
      font-size: 13px;
      font-weight: 500;
      margin-bottom: 10px;
    }

    /* 案例瀑布 */
    .case-row {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 50px;
      align-items: center;
      margin-bottom: 80px;
    }
    .case-row:last-child { margin-bottom: 0; }
    .case-img img {
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-sm);
    }
    .case-content h3 {
      margin-bottom: 12px;
    }
    .case-data {
      font-size: 28px;
      font-weight: 700;
      color: var(--accent);
      margin: 16px 0 8px;
    }

    /* 方案对比 */
    .compare-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 30px;
    }
    .compare-card {
      background: var(--card-bg);
      border-radius: var(--radius-card);
      padding: 32px;
      box-shadow: var(--shadow-sm);
      border: 1px solid var(--border-light);
    }
    .compare-card.old {
      background: #F2EDE6;
    }
    .compare-card.new {
      background: #F9F4EC;
      border-left: 6px solid var(--primary);
    }
    .compare-list {
      list-style: none;
      margin-top: 20px;
    }
    .compare-list li {
      margin-bottom: 12px;
      display: flex;
      align-items: center;
      gap: 10px;
    }
    .fa-check { color: var(--primary); }
    .fa-times { color: #A9A9A9; }

    /* FAQ */
    .faq-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 20px;
    }
    .accordion-item {
      border: 1px solid var(--border-light);
      border-radius: var(--radius-card);
      overflow: hidden;
      background: white;
    }
    .accordion-btn {
      width: 100%;
      text-align: left;
      background: none;
      border: none;
      padding: 20px 24px;
      font-weight: 700;
      font-size: 17px;
      color: var(--secondary);
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
    }
    .accordion-content {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease-in-out;
      background: #F5F0EA;
      padding: 0 24px;
    }
    .accordion-content p {
      padding: 16px 0;
      color: var(--text-body);
    }
    .accordion-item.active .accordion-content {
      max-height: 200px;
    }

    /* CTA */
    .cta-section {
      background: var(--secondary);
      color: white;
    }
    .cta-form {
      display: flex;
      gap: 15px;
      flex-wrap: wrap;
      align-items: center;
      justify-content: center;
      margin: 30px 0;
    }
    .cta-form input {
      padding: 14px 20px;
      border-radius: var(--radius-input);
      border: 1px solid #5A6A72;
      background: white;
      min-width: 200px;
      flex: 1;
    }
    .cta-form button {
      flex: 0 0 auto;
    }

    /* Footer */
    .site-footer {
      background: var(--secondary);
      color: #C2B8AD;
      padding: 60px 0 20px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1.5fr 1fr;
      gap: 40px;
    }
    .footer-links a {
      display: block;
      color: #C2B8AD;
      margin-bottom: 8px;
    }

    @media (max-width: 1024px) {
      h1 { font-size: 38px; }
      h2 { font-size: 30px; }
      .hero-grid { grid-template-columns: 1fr; gap: 40px; }
      .advantages-grid { grid-template-columns: 1fr; }
      .highlight-grid { grid-template-columns: 1fr; }
      .case-row { grid-template-columns: 1fr; }
      .faq-grid { grid-template-columns: 1fr; }
      .footer-grid { grid-template-columns: 1fr 1fr; }
    }
    @media (max-width: 640px) {
      .nav-links { display: none; }
      .mobile-toggle { display: block; }
      .hero-buttons { flex-direction: column; }
      .cta-form { flex-direction: column; }
      .compare-grid { grid-template-columns: 1fr; }
    }