/* roulang page: index */
:root {
      --primary: #FF6B6B;
      --primary-hover: #E55A5A;
      --secondary: #FDCB6E;
      --dark: #2D3436;
      --body-bg: #FDF6F0;
      --card-bg: #FFFFFF;
      --text-dark: #2D3436;
      --text-body: #4A4A4A;
      --text-light: #888888;
      --text-on-dark: #FFFFFF;
      --text-muted-on-dark: #CCCCCC;
      --shadow-card: 0 4px 20px rgba(0,0,0,0.04);
      --shadow-card-hover: 0 8px 30px rgba(0,0,0,0.08);
      --shadow-button: 0 4px 12px rgba(255,107,107,0.3);
      --radius-card: 16px;
      --radius-button: 8px;
      --font-heading: 'Segoe UI', '思源黑体 Bold', 'Noto Sans SC Bold', system-ui, -apple-system, sans-serif;
      --font-body: 'Segoe UI', '思源黑体 Regular', 'Noto Sans SC', system-ui, -apple-system, sans-serif;
      --transition: 0.3s ease;
      --max-width: 1280px;
      --section-padding: 100px 0;
    }

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

    body {
      font-family: var(--font-body);
      background-color: var(--body-bg);
      color: var(--text-body);
      font-size: 16px;
      line-height: 1.8;
      -webkit-font-smoothing: antialiased;
    }

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

    a {
      text-decoration: none;
      color: inherit;
      transition: color var(--transition);
    }

    button, .btn {
      cursor: pointer;
      font-family: var(--font-body);
      border: none;
      outline: none;
      transition: all var(--transition);
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      font-weight: 600;
      border-radius: var(--radius-button);
      padding: 14px 32px;
      font-size: 16px;
    }

    .container {
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 32px;
    }

    @media (max-width: 768px) {
      .container {
        padding: 0 20px;
      }
      :root {
        --section-padding: 70px 0;
      }
    }

    /* 导航 */
    .header {
      background: var(--card-bg);
      position: sticky;
      top: 0;
      z-index: 1000;
      box-shadow: 0 2px 12px rgba(0,0,0,0.02);
    }
    .nav-bar {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 72px;
    }
    .logo {
      font-family: var(--font-heading);
      font-size: 26px;
      font-weight: 700;
      color: var(--primary);
      letter-spacing: 1px;
      display: flex;
      align-items: center;
      gap: 6px;
    }
    .logo i {
      font-size: 28px;
    }
    .nav-links {
      display: flex;
      gap: 32px;
      align-items: center;
    }
    .nav-links a {
      color: var(--text-dark);
      font-weight: 500;
      position: relative;
      padding: 8px 0;
    }
    .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%;
    }
    .menu-toggle {
      display: none;
      font-size: 28px;
      background: none;
      border: none;
      color: var(--dark);
      cursor: pointer;
    }
    @media (max-width: 768px) {
      .nav-links {
        position: fixed;
        top: 0;
        right: -100%;
        width: 75%;
        max-width: 300px;
        height: 100vh;
        background: var(--body-bg);
        flex-direction: column;
        padding: 80px 30px 30px;
        gap: 28px;
        box-shadow: -5px 0 25px rgba(0,0,0,0.1);
        transition: right 0.3s ease;
        z-index: 999;
      }
      .nav-links.active {
        right: 0;
      }
      .menu-toggle {
        display: block;
        z-index: 1001;
      }
      .nav-links a {
        font-size: 20px;
      }
      .close-menu {
        position: absolute;
        top: 24px;
        right: 24px;
        font-size: 32px;
        background: none;
        border: none;
        color: var(--dark);
        cursor: pointer;
      }
    }

    /* 首屏 Hero */
    .hero {
      display: flex;
      align-items: center;
      gap: 60px;
      padding: 60px 0 80px;
      min-height: 85vh;
    }
    .hero-left {
      flex: 1 1 50%;
    }
    .hero-right {
      flex: 1 1 50%;
      position: relative;
    }
    .hero-right img {
      border-radius: 28px;
      width: 100%;
      height: auto;
      filter: brightness(0.98) saturate(1.1);
      box-shadow: 0 25px 45px rgba(255,107,107,0.12);
    }
    .hero h1 {
      font-family: var(--font-heading);
      font-size: 48px;
      line-height: 1.25;
      color: var(--dark);
      margin-bottom: 24px;
      font-weight: 700;
    }
    .hero h1 span {
      color: var(--primary);
    }
    .hero-sub {
      font-size: 18px;
      color: var(--text-body);
      margin-bottom: 32px;
      max-width: 480px;
    }
    .btn-primary {
      background: var(--primary);
      color: white;
      box-shadow: var(--shadow-button);
    }
    .btn-primary:hover {
      background: var(--primary-hover);
      transform: translateY(-2px);
    }
    @media (max-width: 768px) {
      .hero {
        flex-direction: column-reverse;
        gap: 32px;
        text-align: center;
        padding: 30px 0 60px;
      }
      .hero h1 {
        font-size: 36px;
      }
      .hero-sub {
        max-width: 100%;
        margin-left: auto;
        margin-right: auto;
      }
      .hero-left {
        display: flex;
        flex-direction: column;
        align-items: center;
      }
    }

    /* 板块通用 */
    section {
      padding: var(--section-padding);
    }
    .section-title {
      font-family: var(--font-heading);
      font-size: 36px;
      font-weight: 700;
      color: var(--dark);
      text-align: center;
      margin-bottom: 16px;
    }
    .section-sub {
      text-align: center;
      color: var(--text-light);
      margin-bottom: 50px;
      font-size: 17px;
      max-width: 650px;
      margin-left: auto;
      margin-right: auto;
    }

    /* 亮点网格 */
    .highlights-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }
    .highlight-card {
      background: var(--card-bg);
      padding: 32px 28px;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-card);
      transition: all var(--transition);
      text-align: left;
    }
    .highlight-card:hover {
      box-shadow: var(--shadow-card-hover);
      transform: translateY(-4px);
    }
    .highlight-icon {
      font-size: 38px;
      color: var(--primary);
      margin-bottom: 22px;
      transition: transform 0.3s;
    }
    .highlight-card:hover .highlight-icon {
      transform: scale(1.08);
    }
    .highlight-card h3 {
      font-size: 22px;
      font-weight: 700;
      color: var(--dark);
      margin-bottom: 12px;
    }
    @media (max-width: 1024px) {
      .highlights-grid {
        grid-template-columns: repeat(2, 1fr);
      }
    }
    @media (max-width: 520px) {
      .highlights-grid {
        grid-template-columns: 1fr;
      }
      .highlight-card {
        padding: 24px;
      }
    }

    /* 案例瀑布 */
    .case-grid {
      columns: 3;
      column-gap: 28px;
    }
    .case-card {
      break-inside: avoid;
      background: var(--card-bg);
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-card);
      margin-bottom: 28px;
      overflow: hidden;
      transition: all var(--transition);
    }
    .case-card:hover {
      box-shadow: var(--shadow-card-hover);
      transform: translateY(-4px);
    }
    .case-img {
      width: 100%;
      display: block;
      transition: transform 0.4s ease;
      border-radius: var(--radius-card) var(--radius-card) 0 0;
    }
    .case-card:hover .case-img {
      transform: scale(1.03);
    }
    .case-content {
      padding: 22px 24px 24px;
    }
    .case-content h3 {
      font-size: 20px;
      font-weight: 700;
      color: var(--dark);
      margin-bottom: 8px;
    }
    .case-link {
      color: var(--secondary);
      font-weight: 600;
      display: inline-block;
      margin-top: 12px;
    }
    .case-link:hover {
      color: var(--primary);
    }
    @media (max-width: 1024px) {
      .case-grid {
        columns: 2;
      }
    }
    @media (max-width: 520px) {
      .case-grid {
        columns: 1;
      }
    }

    /* 方案对比 */
    .compare-wrapper {
      display: flex;
      gap: 40px;
      align-items: flex-start;
    }
    .compare-col {
      flex: 1;
      background: var(--card-bg);
      border-radius: var(--radius-card);
      padding: 36px 32px;
      box-shadow: var(--shadow-card);
    }
    .compare-col h3 {
      font-size: 26px;
      margin-bottom: 24px;
      font-weight: 700;
      color: var(--dark);
    }
    .compare-item {
      display: flex;
      align-items: center;
      gap: 12px;
      margin-bottom: 18px;
      font-size: 16px;
    }
    .compare-col.left .compare-item {
      color: #999;
      text-decoration: line-through;
      text-decoration-color: #ccc;
    }
    .compare-col.right .compare-item {
      color: var(--dark);
      font-weight: 600;
    }
    .check-icon {
      color: var(--primary);
      font-size: 18px;
      min-width: 20px;
    }
    @media (max-width: 768px) {
      .compare-wrapper {
        flex-direction: column;
        gap: 28px;
      }
    }

    /* FAQ */
    .faq-list {
      max-width: 860px;
      margin: 0 auto;
    }
    .faq-item {
      border-radius: 14px;
      margin-bottom: 16px;
      background: var(--card-bg);
      overflow: hidden;
      transition: all var(--transition);
    }
    .faq-item:nth-child(even) {
      background: #FFF5F0;
    }
    .faq-question {
      padding: 22px 28px;
      font-weight: 700;
      font-size: 18px;
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
      color: var(--dark);
    }
    .faq-toggle {
      font-size: 22px;
      transition: transform 0.3s;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.35s ease, padding 0.35s;
      padding: 0 28px;
      color: var(--text-body);
      line-height: 1.8;
    }
    .faq-item.active .faq-answer {
      max-height: 160px;
      padding-bottom: 24px;
    }
    .faq-item.active .faq-toggle {
      transform: rotate(45deg);
    }

    /* CTA 横幅 */
    .cta-band {
      background: var(--dark);
      text-align: center;
      padding: 70px 20px;
      border-radius: 28px;
      margin: 0 20px;
    }
    .cta-band h2 {
      color: white;
      font-size: 34px;
      margin-bottom: 16px;
    }
    .cta-band p {
      color: var(--text-muted-on-dark);
      margin-bottom: 32px;
    }
    .btn-gold {
      background: var(--secondary);
      color: var(--dark);
      font-weight: 700;
    }
    .btn-gold:hover {
      background: #f7b731;
    }

    /* 页脚 */
    .footer {
      background: var(--dark);
      color: var(--text-muted-on-dark);
      padding: 60px 0 30px;
      margin-top: 80px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1.5fr;
      gap: 40px;
    }
    .footer-logo {
      font-size: 24px;
      font-weight: 700;
      color: white;
      margin-bottom: 14px;
    }
    .footer a {
      color: #ccc;
    }
    .footer a:hover {
      color: var(--primary);
    }
    .footer-col p {
      margin-bottom: 10px;
    }
    @media (max-width: 768px) {
      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }
      .cta-band {
        margin: 0 10px;
        padding: 50px 16px;
      }
    }
    @media (max-width: 520px) {
      .footer-grid {
        grid-template-columns: 1fr;
      }
      .cta-band h2 {
        font-size: 26px;
      }
    }

    .text-center { text-align: center; }
    .mt-3 { margin-top: 28px; }