/* roulang page: index */
:root {
      --primary: #2C3E2D;
      --primary-dark: #1F2D20;
      --accent: #C9A96E;
      --bg: #FAFAF7;
      --dark-bg: #1E2A1F;
      --darker-bg: #151D16;
      --text: #1C1C1C;
      --text-muted: #5A5A5A;
      --text-light: rgba(255,255,255,0.8);
      --text-footer: rgba(255,255,255,0.7);
      --border: #E8E4DB;
      --card-bg: #FFFFFF;
      --highlight-bg: #F5F4F0;
      --shadow-sm: 0 2px 12px rgba(0,0,0,0.04);
      --shadow-md: 0 8px 24px rgba(0,0,0,0.08);
      --radius-card: 16px;
      --radius-btn: 8px;
      --radius-img: 16px;
      --font-serif: 'Noto Serif SC', Georgia, 'Times New Roman', serif;
      --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
      --max-width: 1280px;
      --section-gap-desktop: 120px;
      --section-gap-tablet: 80px;
      --section-gap-mobile: 60px;
    }

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

    body {
      font-family: var(--font-sans);
      background-color: var(--bg);
      color: var(--text);
      line-height: 1.7;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
      -moz-osx-font-smoothing: grayscale;
      overflow-x: hidden;
    }

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

    a {
      text-decoration: none;
      color: inherit;
      transition: color 0.25s;
    }

    button, .btn {
      cursor: pointer;
      font-family: var(--font-sans);
      border: none;
      background: none;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      transition: all 0.25s ease;
      font-weight: 600;
      white-space: nowrap;
    }

    .container {
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 40px;
    }

    /* 导航 */
    #header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 100;
      background: rgba(250,250,247,0.92);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
      border-bottom: 1px solid transparent;
      transition: background 0.3s, box-shadow 0.3s, border-color 0.3s;
    }

    #header.scrolled {
      background: #ffffff;
      box-shadow: 0 4px 20px rgba(0,0,0,0.04);
      border-bottom: 1px solid var(--border);
    }

    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 40px;
      height: 72px;
    }

    .logo {
      font-family: var(--font-serif);
      font-weight: 700;
      font-size: 24px;
      color: var(--primary);
      letter-spacing: -0.02em;
      white-space: nowrap;
    }

    .nav-links {
      display: flex;
      align-items: center;
      gap: 32px;
    }

    .nav-links a {
      font-size: 15px;
      font-weight: 500;
      color: var(--text);
      transition: color 0.25s;
      padding: 4px 0;
    }

    .nav-links a:hover {
      color: var(--primary);
    }

    .nav-cta {
      background: var(--primary);
      color: white;
      padding: 10px 22px;
      border-radius: var(--radius-btn);
      font-size: 14px;
      font-weight: 600;
      transition: all 0.25s;
    }

    .nav-cta:hover {
      background: var(--primary-dark);
      transform: scale(1.03);
    }

    .mobile-nav {
      display: none;
    }

    /* 板块通用 */
    section {
      padding: var(--section-gap-desktop) 0;
    }

    .section-title {
      font-family: var(--font-serif);
      font-weight: 700;
      font-size: 36px;
      letter-spacing: -0.02em;
      color: var(--text);
      margin-bottom: 16px;
    }

    .section-subtitle {
      font-size: 18px;
      color: var(--text-muted);
      max-width: 600px;
    }

    /* 按钮系统 */
    .btn-primary {
      background: var(--primary);
      color: white;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 16px;
    }
    .btn-primary:hover {
      background: var(--primary-dark);
      transform: scale(1.03);
    }

    .btn-outline {
      background: transparent;
      border: 1.5px solid var(--primary);
      color: var(--primary);
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 16px;
    }
    .btn-outline:hover {
      background: rgba(44,62,45,0.08);
      transform: scale(1.03);
    }

    .btn-accent {
      background: var(--accent);
      color: var(--text);
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
    }
    .btn-accent:hover {
      filter: brightness(1.05);
      transform: scale(1.03);
    }

    /* Hero */
    #hero {
      padding-top: 140px;
      padding-bottom: 80px;
    }
    .hero-grid {
      display: flex;
      align-items: center;
      gap: 60px;
    }
    .hero-left {
      flex: 1 1 55%;
      animation: fadeUp 0.8s ease-out 0.2s both;
    }
    .hero-right {
      flex: 1 1 45%;
      animation: fadeInRight 0.8s ease-out 0.2s both;
    }
    .hero-right img {
      width: 100%;
      border-radius: var(--radius-img);
      box-shadow: var(--shadow-md);
      aspect-ratio: 4/3;
      object-fit: cover;
    }
    .hero-title {
      font-family: var(--font-serif);
      font-weight: 700;
      font-size: 48px;
      line-height: 1.15;
      letter-spacing: -0.03em;
      color: var(--primary);
      margin-bottom: 20px;
    }
    .hero-desc {
      font-size: 18px;
      color: var(--text-muted);
      max-width: 420px;
      margin-bottom: 32px;
    }
    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }

    /* 亮点网格 */
    #highlights .section-header {
      margin-bottom: 48px;
    }
    .highlights-grid {
      display: grid;
      grid-template-columns: 1.2fr 0.8fr 1fr;
      gap: 24px;
    }
    .highlight-item {
      background: var(--highlight-bg);
      padding: 32px 28px;
      border-radius: var(--radius-card);
      transition: all 0.3s ease-out;
      border-left: 3px solid transparent;
    }
    .highlight-item:hover {
      background: white;
      box-shadow: var(--shadow-sm);
      border-left: 3px solid var(--primary);
      transform: translateY(-4px);
    }
    .highlight-icon {
      font-size: 32px;
      color: var(--accent);
      margin-bottom: 20px;
    }
    .highlight-item h3 {
      font-family: var(--font-serif);
      font-weight: 700;
      font-size: 22px;
      margin-bottom: 8px;
    }
    .highlight-item p {
      color: var(--text-muted);
      font-size: 15px;
    }

    /* 案例瀑布 */
    #cases .section-header {
      margin-bottom: 48px;
    }
    .cases-masonry {
      columns: 3;
      column-gap: 24px;
    }
    .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: transform 0.3s ease, box-shadow 0.3s ease;
      position: relative;
    }
    .case-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-md);
    }
    .case-img {
      position: relative;
      aspect-ratio: 4/3;
      overflow: hidden;
    }
    .case-img img {
      width: 100%;
      height: 100%;
      object-fit: cover;
      transition: transform 0.4s;
    }
    .case-card:hover .case-img img {
      transform: scale(1.05);
    }
    .case-overlay {
      position: absolute;
      bottom: 0;
      left: 0;
      right: 0;
      background: linear-gradient(transparent, rgba(44,62,45,0.75));
      padding: 24px;
      color: white;
      transform: translateY(100%);
      transition: transform 0.3s ease;
    }
    .case-card:hover .case-overlay {
      transform: translateY(0);
    }
    .case-tag {
      font-size: 13px;
      background: rgba(255,255,255,0.2);
      padding: 4px 12px;
      border-radius: 20px;
      display: inline-block;
      margin-bottom: 8px;
    }
    .case-title {
      font-weight: 700;
      font-size: 20px;
      margin-bottom: 4px;
    }
    .case-link {
      color: white;
      font-weight: 600;
      font-size: 14px;
      text-decoration: underline;
      text-underline-offset: 3px;
    }

    /* 方案对比 */
    #solutions .compare-wrapper {
      display: flex;
      gap: 40px;
      align-items: flex-start;
    }
    .compare-col {
      flex: 1;
    }
    .compare-divider {
      width: 1px;
      background: var(--border);
      align-self: stretch;
    }
    .compare-item {
      display: flex;
      align-items: flex-start;
      gap: 12px;
      margin-bottom: 24px;
      font-size: 16px;
    }
    .compare-item i {
      font-size: 18px;
      margin-top: 2px;
    }
    .pain-text {
      color: var(--text-muted);
      text-decoration: line-through;
    }
    .solution-text {
      color: var(--primary);
      font-weight: 600;
    }

    /* FAQ */
    #faq .faq-container {
      max-width: 800px;
      margin: 0 auto;
    }
    .faq-item {
      border-bottom: 1px solid var(--border);
      padding: 20px 0 20px 24px;
      position: relative;
      cursor: pointer;
    }
    .faq-item::before {
      content: '';
      position: absolute;
      left: 0;
      top: 16px;
      bottom: 16px;
      width: 3px;
      background: transparent;
      transition: background 0.2s;
    }
    .faq-item:hover::before {
      background: var(--primary);
    }
    .faq-question {
      font-weight: 600;
      font-size: 18px;
      display: flex;
      justify-content: space-between;
      align-items: center;
    }
    .faq-icon {
      transition: transform 0.3s;
      font-size: 20px;
      color: var(--primary);
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.35s ease, padding 0.3s;
      color: var(--text-muted);
      font-size: 16px;
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding-top: 12px;
      padding-bottom: 8px;
    }
    .faq-item.active .faq-icon {
      transform: rotate(45deg);
    }

    /* CTA */
    #cta {
      background: var(--dark-bg);
      padding: 100px 0;
      text-align: center;
    }
    #cta .cta-title {
      color: white;
      font-size: 36px;
    }
    #cta .cta-sub {
      color: var(--text-light);
      margin-bottom: 32px;
    }
    .cta-buttons {
      display: flex;
      gap: 16px;
      justify-content: center;
      flex-wrap: wrap;
    }
    .trust-text {
      margin-top: 28px;
      color: rgba(255,255,255,0.5);
      font-size: 14px;
    }

    /* 页脚 */
    #footer {
      background: var(--dark-bg);
      color: var(--text-footer);
      padding: 60px 0 0;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 1.5fr 1fr 1fr 1fr;
      gap: 40px;
    }
    .footer-logo {
      font-family: var(--font-serif);
      font-weight: 700;
      font-size: 24px;
      color: white;
      margin-bottom: 12px;
    }
    .footer-desc {
      font-size: 14px;
      margin-bottom: 16px;
    }
    .footer-col h4 {
      color: white;
      font-weight: 600;
      margin-bottom: 16px;
    }
    .footer-col a, .footer-col p {
      display: block;
      margin-bottom: 8px;
      font-size: 14px;
      color: var(--text-footer);
    }
    .footer-col a:hover {
      color: white;
    }
    .copyright {
      background: var(--darker-bg);
      text-align: center;
      padding: 20px 0;
      font-size: 13px;
      color: rgba(255,255,255,0.4);
      margin-top: 40px;
    }

    @keyframes fadeUp {
      from { opacity: 0; transform: translateY(20px); }
      to { opacity: 1; transform: translateY(0); }
    }
    @keyframes fadeInRight {
      from { opacity: 0; transform: translateX(20px); }
      to { opacity: 1; transform: translateX(0); }
    }

    /* 响应式 */
    @media (max-width: 1024px) {
      .container { padding: 0 24px; }
      .hero-grid { gap: 40px; }
      .hero-title { font-size: 40px; }
      .highlights-grid { grid-template-columns: 1fr 1fr; }
      .cases-masonry { columns: 2; }
      .compare-wrapper { flex-direction: column; gap: 32px; }
      .compare-divider { display: none; }
    }

    @media (max-width: 768px) {
      .nav-container { padding: 0 20px; }
      .nav-links { display: none; }
      .mobile-nav {
        display: flex;
        position: fixed;
        bottom: 16px;
        left: 16px;
        right: 16px;
        background: white;
        border-radius: 40px;
        box-shadow: 0 8px 30px rgba(0,0,0,0.12);
        padding: 8px 16px;
        justify-content: space-around;
        z-index: 110;
      }
      .mobile-nav a {
        display: flex;
        flex-direction: column;
        align-items: center;
        font-size: 12px;
        color: var(--text-muted);
        padding: 8px;
      }
      .mobile-nav a i { font-size: 20px; margin-bottom: 2px; }
      .hero-grid { flex-direction: column; }
      .hero-left, .hero-right { flex: unset; width: 100%; }
      .highlights-grid { grid-template-columns: 1fr 1fr; }
      .cases-masonry { columns: 1; }
      .footer-grid { grid-template-columns: 1fr 1fr; }
      section { padding: var(--section-gap-mobile) 0; }
      #hero { padding-top: 100px; }
    }