/* roulang page: index */
:root {
      --primary-black: #1A1715;
      --accent-gold: #C8A46B;
      --accent-gold-hover: #B28A4A;
      --bg-warm: #F7F4EF;
      --text-primary: #2C2A27;
      --text-secondary: #4A4540;
      --accent-green: #2E5C4A;
      --card-bg: #FFFFFF;
      --border-light: #E5E0D9;
      --border-input: #D9D4CC;
      --shadow-sm: 0 4px 20px rgba(0,0,0,0.04);
      --shadow-md: 0 8px 30px rgba(0,0,0,0.08);
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-input: 6px;
      --font-serif: 'Noto Serif SC', 'Source Han Serif SC', 'Songti SC', serif;
      --font-sans: 'Inter', 'SF Pro Text', 'PingFang SC', 'Microsoft YaHei', sans-serif;
      --transition: 0.3s ease;
      --header-height: 72px;
      --container-max: 1280px;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    body {
      font-family: var(--font-sans);
      background-color: var(--bg-warm);
      color: var(--text-primary);
      line-height: 1.8;
      font-size: 16px;
      scroll-behavior: smooth;
      -webkit-font-smoothing: antialiased;
    }
    .container {
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 40px;
    }
    h1, h2, h3, h4 {
      font-family: var(--font-serif);
      color: var(--primary-black);
    }
    h1 {
      font-size: clamp(2.4rem, 5vw, 3.5rem);
      line-height: 1.2;
      font-weight: 700;
    }
    h2 {
      font-size: 2rem;
      font-weight: 600;
      line-height: 1.3;
      margin-bottom: 1rem;
    }
    h3 {
      font-size: 1.25rem;
      font-weight: 500;
      line-height: 1.5;
    }
    h4 {
      font-size: 1.1rem;
      font-weight: 600;
      line-height: 1.4;
    }
    a {
      color: var(--accent-gold);
      text-decoration: none;
      transition: color var(--transition), border var(--transition);
    }
    a:hover {
      color: var(--accent-gold-hover);
    }
    img {
      max-width: 100%;
      display: block;
      border-radius: var(--radius-card);
    }
    button, .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 1rem;
      cursor: pointer;
      transition: all var(--transition);
      border: 2px solid transparent;
      font-family: var(--font-sans);
      letter-spacing: 0.5px;
    }
    .btn-primary {
      background-color: var(--accent-gold);
      color: white;
      border-color: var(--accent-gold);
    }
    .btn-primary:hover {
      background-color: var(--accent-gold-hover);
      border-color: var(--accent-gold-hover);
      transform: translateY(-2px);
      box-shadow: var(--shadow-md);
    }
    .btn-outline {
      background: transparent;
      border-color: var(--accent-gold);
      color: var(--accent-gold);
    }
    .btn-outline:hover {
      background-color: rgba(200, 164, 107, 0.08);
      border-color: var(--accent-gold-hover);
      color: var(--accent-gold-hover);
    }
    .section {
      padding: 100px 0;
    }
    .section-header {
      text-align: center;
      margin-bottom: 60px;
    }
    .section-header p {
      color: var(--text-secondary);
      font-size: 1.1rem;
      max-width: 600px;
      margin: 1rem auto 0;
    }
    hr {
      border: 0;
      height: 1px;
      background: var(--border-light);
      margin: 40px 0;
    }

    /* 导航 */
    #header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: var(--header-height);
      background: rgba(255,255,255,0.92);
      backdrop-filter: blur(12px);
      border-bottom: 1px solid var(--border-light);
      z-index: 100;
      display: flex;
      align-items: center;
    }
    .nav-container {
      display: flex;
      justify-content: space-between;
      align-items: center;
      width: 100%;
    }
    .logo {
      font-family: var(--font-serif);
      font-weight: 700;
      font-size: 1.6rem;
      color: var(--accent-gold);
      letter-spacing: 1px;
    }
    .nav-links {
      display: flex;
      gap: 32px;
      align-items: center;
      list-style: none;
    }
    .nav-links a {
      color: var(--text-primary);
      font-weight: 500;
      font-size: 1rem;
      position: relative;
      padding: 4px 0;
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: -4px;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--accent-gold);
      transition: width var(--transition);
    }
    .nav-links a:hover::after,
    .nav-links a.active::after {
      width: 100%;
    }
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
    }
    .hamburger span {
      width: 24px;
      height: 2px;
      background: var(--primary-black);
      border-radius: 4px;
    }
    .mobile-menu {
      display: none;
    }

    /* Hero */
    #hero {
      padding-top: calc(var(--header-height) + 40px);
      padding-bottom: 60px;
      background: var(--bg-warm);
      display: flex;
      align-items: center;
    }
    .hero-grid {
      display: grid;
      grid-template-columns: 1.1fr 0.9fr;
      gap: 60px;
      align-items: center;
    }
    .hero-content h1 {
      margin-bottom: 1.2rem;
      color: var(--primary-black);
    }
    .hero-content p {
      font-size: 1.2rem;
      color: var(--text-secondary);
      margin-bottom: 2rem;
      max-width: 90%;
    }
    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .hero-image img {
      width: 100%;
      height: auto;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-md);
      transform: translateY(-8px);
      transition: transform 0.4s ease;
    }
    .hero-image img:hover {
      transform: translateY(-12px);
    }

    /* 亮点网格 */
    .grid-2x3 {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .highlight-card {
      background: var(--card-bg);
      padding: 32px;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-sm);
      transition: all var(--transition);
      border-bottom: 2px solid var(--border-light);
      text-align: left;
    }
    .highlight-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-md);
      border-bottom-color: var(--accent-gold);
    }
    .icon-circle {
      width: 48px;
      height: 48px;
      border: 2px solid var(--accent-gold);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      margin-bottom: 20px;
      color: var(--accent-gold);
      font-size: 1.4rem;
    }
    .highlight-card h4 {
      margin-bottom: 12px;
    }
    .highlight-card p {
      color: var(--text-secondary);
      font-size: 0.95rem;
    }

    /* 案例瀑布流 */
    .masonry {
      columns: 3;
      column-gap: 24px;
      margin-top: 30px;
    }
    .case-card {
      break-inside: avoid;
      margin-bottom: 24px;
      background: var(--card-bg);
      border-radius: var(--radius-card);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
      transition: all var(--transition);
      position: relative;
    }
    .case-card:hover {
      transform: scale(1.02);
      box-shadow: var(--shadow-md);
    }
    .case-img {
      width: 100%;
      display: block;
      border-radius: 0;
    }
    .case-overlay {
      position: absolute;
      bottom: 0;
      left: 0;
      right: 0;
      background: linear-gradient(to top, rgba(26,23,21,0.8), transparent);
      color: white;
      padding: 24px;
      transform: translateY(100%);
      transition: transform var(--transition);
    }
    .case-card:hover .case-overlay {
      transform: translateY(0);
    }
    .case-overlay h4 {
      color: white;
      margin-bottom: 4px;
    }

    /* 方案对比 */
    .compare-table {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 30px;
      margin-top: 40px;
    }
    .compare-col {
      background: var(--card-bg);
      padding: 36px;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-sm);
    }
    .compare-col.recommend {
      border: 2px solid var(--accent-gold);
      background: #FFFBF5;
      position: relative;
    }
    .compare-col h3 {
      margin-bottom: 24px;
      font-size: 1.4rem;
    }
    .compare-item {
      display: flex;
      align-items: center;
      gap: 12px;
      margin-bottom: 16px;
      font-size: 1rem;
    }
    .check {
      color: var(--accent-gold);
      font-weight: bold;
    }
    .cross {
      color: #aaa;
    }

    /* 数据信任带 */
    #trust {
      background: var(--primary-black);
      padding: 60px 0;
    }
    .trust-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      text-align: center;
      gap: 30px;
    }
    .trust-num {
      font-size: 2.4rem;
      font-weight: 700;
      color: var(--accent-gold);
      font-family: var(--font-serif);
    }
    .trust-label {
      color: #ddd;
      margin-top: 8px;
    }

    /* FAQ */
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
    }
    .faq-item {
      border-bottom: 1px solid var(--border-light);
      padding: 20px 0;
    }
    .faq-question {
      font-weight: 600;
      font-size: 1.1rem;
      display: flex;
      justify-content: space-between;
      cursor: pointer;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.35s ease;
      color: var(--text-secondary);
      padding-left: 20px;
    }
    .faq-item.open .faq-answer {
      max-height: 200px;
      margin-top: 12px;
    }

    /* CTA */
    #cta {
      background: var(--primary-black);
      padding: 80px 0;
      color: white;
    }
    .cta-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 40px;
      align-items: center;
    }
    .cta-form input {
      width: 100%;
      padding: 14px;
      margin-bottom: 12px;
      border-radius: var(--radius-input);
      border: 1px solid var(--border-input);
      background: white;
    }

    /* 页脚 */
    #footer {
      background: var(--primary-black);
      color: #ccc;
      padding: 60px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 30px;
    }

    @media (max-width: 1024px) {
      .container { padding: 0 24px; }
      .hero-grid { grid-template-columns: 1fr; }
      .grid-2x3 { grid-template-columns: repeat(2,1fr); }
      .masonry { columns: 2; }
    }
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .hamburger { display: flex; }
      .grid-2x3, .trust-grid, .compare-table { grid-template-columns: 1fr; }
      .masonry { columns: 1; }
      .cta-grid { grid-template-columns: 1fr; }
      .footer-grid { grid-template-columns: 1fr 1fr; }
    }