/* roulang page: index */
:root {
      --primary: #1E1E1E;
      --accent: #C59B5F;
      --accent-hover: #B08A4A;
      --bg: #FAF7F2;
      --card-bg: #FFFFFF;
      --text-on-dark: #F0EFEA;
      --text-muted: #5F5B53;
      --border-light: rgba(0,0,0,0.05);
      --shadow-sm: 0 2px 8px rgba(0,0,0,0.03);
      --shadow-md: 0 8px 24px rgba(0,0,0,0.06);
      --shadow-lg: 0 12px 32px rgba(0,0,0,0.08);
      --radius-card: 12px;
      --radius-btn: 6px;
      --font-heading: 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', sans-serif;
      --font-body: 'PingFang SC', 'Microsoft YaHei', 'Segoe UI', Roboto, sans-serif;
      --transition: all 0.25s ease;
      --max-width: 1200px;
    }

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

    body {
      font-family: var(--font-body);
      background: var(--bg);
      color: var(--primary);
      line-height: 1.7;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }

    h1, h2, h3, h4 {
      font-family: var(--font-heading);
      font-weight: 600;
      letter-spacing: -0.01em;
    }

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

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

    /* 按钮系统 */
    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      font-weight: 500;
      border-radius: var(--radius-btn);
      padding: 14px 32px;
      font-size: 16px;
      transition: var(--transition);
      cursor: pointer;
      border: none;
      background: transparent;
      line-height: 1.2;
      text-align: center;
    }
    .btn-primary {
      background: var(--accent);
      color: #fff;
      box-shadow: 0 4px 10px rgba(197,155,95,0.25);
    }
    .btn-primary:hover {
      background: var(--accent-hover);
      color: #fff;
      transform: translateY(-2px);
      box-shadow: 0 8px 18px rgba(197,155,95,0.3);
    }
    .btn-outline {
      border: 1.5px solid var(--accent);
      color: var(--accent);
    }
    .btn-outline:hover {
      background: var(--accent);
      color: #fff;
      transform: translateY(-2px);
    }
    .btn-white-outline {
      border: 1.5px solid #fff;
      color: #fff;
    }
    .btn-white-outline:hover {
      background: #fff;
      color: var(--primary);
    }

    /* 导航 */
    #main-nav {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 50;
      background: transparent;
      transition: background 0.3s, backdrop-filter 0.3s, box-shadow 0.3s;
      padding: 16px 0;
    }
    #main-nav.scrolled {
      background: rgba(250,247,242,0.92);
      backdrop-filter: blur(12px);
      box-shadow: 0 1px 12px rgba(0,0,0,0.04);
    }
    .nav-grid {
      display: flex;
      align-items: center;
      justify-content: space-between;
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 24px;
    }
    .logo {
      font-family: var(--font-heading);
      font-size: 24px;
      font-weight: 700;
      color: var(--primary);
      letter-spacing: 1px;
    }
    .logo span {
      color: var(--accent);
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 32px;
    }
    .nav-links a {
      font-weight: 500;
      font-size: 16px;
      color: var(--primary);
    }
    .nav-links a:hover {
      color: var(--accent);
    }
    .mega-trigger {
      position: relative;
      cursor: pointer;
    }
    .mega-panel {
      position: absolute;
      right: 0;
      top: 100%;
      margin-top: 16px;
      width: 420px;
      background: var(--card-bg);
      border-radius: 0 0 var(--radius-card) var(--radius-card);
      box-shadow: var(--shadow-lg);
      padding: 24px;
      display: none;
      opacity: 0;
      transform: translateY(-8px);
      transition: opacity 0.2s, transform 0.2s;
      z-index: 60;
    }
    .mega-trigger:hover .mega-panel {
      display: flex;
      opacity: 1;
      transform: translateY(0);
      gap: 24px;
    }
    .mega-col {
      flex: 1;
    }
    .mega-col h4 {
      font-size: 15px;
      color: var(--accent);
      margin-bottom: 12px;
      font-weight: 600;
    }
    .mega-item {
      display: flex;
      align-items: center;
      gap: 10px;
      margin-bottom: 14px;
      font-size: 15px;
    }
    .mega-item i {
      color: var(--accent);
      font-size: 18px;
    }
    .hamburger {
      display: none;
      font-size: 24px;
      background: none;
      border: none;
      color: var(--primary);
    }
    .mobile-menu {
      display: none;
    }

    /* Hero */
    #hero {
      min-height: 92vh;
      display: flex;
      align-items: center;
      background: var(--bg);
      position: relative;
      overflow: hidden;
    }
    .hero-flex {
      display: flex;
      align-items: center;
      gap: 56px;
      width: 100%;
    }
    .hero-left {
      flex: 0 0 55%;
    }
    .hero-right {
      flex: 0 0 45%;
      position: relative;
    }
    .hero-right img {
      width: 100%;
      border-radius: 20px;
      box-shadow: var(--shadow-lg);
      object-fit: cover;
      aspect-ratio: 4/3;
    }
    .hero-left h1 {
      font-size: 52px;
      font-weight: 700;
      line-height: 1.2;
      margin-bottom: 20px;
    }
    .hero-left .sub {
      font-size: 18px;
      color: var(--text-muted);
      margin-bottom: 32px;
      max-width: 480px;
    }
    .hero-buttons {
      display: flex;
      gap: 18px;
      flex-wrap: wrap;
    }

    /* 板块通用 */
    section {
      padding: 100px 0;
    }
    .section-title {
      font-size: 36px;
      margin-bottom: 16px;
      font-weight: 600;
    }
    .section-desc {
      color: var(--text-muted);
      margin-bottom: 48px;
      font-size: 18px;
      max-width: 700px;
    }

    /* Highlights */
    .highlights-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 40px;
    }
    .highlight-item {
      text-align: left;
      background: transparent;
      padding: 0;
    }
    .highlight-icon {
      font-size: 32px;
      color: var(--accent);
      margin-bottom: 18px;
    }
    .highlight-item h3 {
      font-size: 20px;
      margin-bottom: 8px;
    }

    /* Solutions 对比 */
    .solutions-cards {
      display: flex;
      gap: 32px;
      align-items: stretch;
    }
    .solution-card {
      background: var(--card-bg);
      border-radius: var(--radius-card);
      padding: 32px;
      flex: 1;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
      border: 1px solid transparent;
    }
    .solution-card.featured {
      background: rgba(197,155,95,0.06);
      border-color: var(--accent);
      transform: scale(1.02);
    }
    .solution-card h3 {
      font-size: 24px;
      margin-bottom: 12px;
    }
    .solution-list {
      list-style: none;
      margin: 24px 0;
    }
    .solution-list li {
      margin-bottom: 12px;
      display: flex;
      align-items: center;
      gap: 10px;
    }
    .solution-list i {
      color: var(--accent);
    }

    /* 案例瀑布流 */
    .masonry {
      column-count: 3;
      column-gap: 24px;
    }
    .case-card {
      break-inside: avoid;
      background: var(--card-bg);
      border-radius: var(--radius-card);
      margin-bottom: 24px;
      overflow: hidden;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
    }
    .case-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-md);
    }
    .case-img {
      width: 100%;
      display: block;
      transition: transform 0.3s;
      object-fit: cover;
    }
    .case-card:hover .case-img {
      transform: scale(1.02);
    }
    .case-info {
      padding: 20px;
    }
    .case-tag {
      background: rgba(197,155,95,0.15);
      color: var(--accent);
      font-size: 13px;
      padding: 4px 12px;
      border-radius: 20px;
      display: inline-block;
      margin-bottom: 10px;
    }

    /* Trust */
    #trust {
      background: var(--primary);
      color: var(--text-on-dark);
      padding: 80px 0;
    }
    .trust-numbers {
      display: flex;
      justify-content: space-around;
      text-align: center;
    }
    .trust-item {
      font-size: 42px;
      font-weight: 700;
      color: var(--accent);
    }

    /* FAQ */
    .faq-item {
      border-bottom: 1px solid var(--border-light);
      padding: 20px 0;
      cursor: pointer;
    }
    .faq-question {
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-weight: 600;
      font-size: 18px;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.35s ease;
      color: var(--text-muted);
    }

    /* CTA */
    #cta {
      background: var(--accent);
      text-align: center;
      padding: 90px 0;
    }

    /* Footer */
    footer {
      background: var(--primary);
      color: #ccc;
      padding: 60px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
    }

    @media (max-width: 1024px) {
      .highlights-grid { grid-template-columns: repeat(2, 1fr); }
      .masonry { column-count: 2; }
    }
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .hamburger { display: block; }
      .hero-flex { flex-direction: column; }
      .hero-left, .hero-right { flex: auto; }
      .solutions-cards { flex-direction: column; }
      .solution-card.featured { transform: none; }
      .masonry { column-count: 1; }
      .trust-numbers { flex-wrap: wrap; gap: 24px; }
      .footer-grid { grid-template-columns: 1fr 1fr; }
      h1 { font-size: 38px; }
    }