/* roulang page: index */
:root {
      --cloud-white: #F5F7FA;
      --morning-mist: #E9ECEF;
      --dawn-orange: #F27A33;
      --golden-light: #C8963E;
      --deep-rock: #2A2F35;
      --shadow-blue: #5E6B7C;
      --pure-white: #FFFFFF;
      --soft-orange-bg: #FFF5EC;
      --light-border: rgba(0,0,0,0.05);
      --shadow-sm: 0 4px 20px rgba(0,0,0,0.04), 0 1px 3px rgba(0,0,0,0.03);
      --shadow-hover: 0 12px 30px rgba(0,0,0,0.08);
      --radius-card: 12px;
      --radius-btn: 8px;
      --transition: 0.3s ease;
      --max-width: 1280px;
      --section-gap: 100px;
    }

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

    body {
      font-family: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", sans-serif;
      background-color: var(--cloud-white);
      color: var(--deep-rock);
      line-height: 1.8;
      font-weight: 400;
      font-size: 1rem;
      -webkit-font-smoothing: antialiased;
    }

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

    /* 导航 */
    .header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      background: var(--pure-white);
      box-shadow: 0 1px 0 var(--light-border);
      z-index: 1000;
      transition: var(--transition);
    }

    .nav {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 72px;
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 24px;
    }

    .logo {
      font-size: 1.8rem;
      font-weight: 700;
      letter-spacing: -0.02em;
      color: var(--deep-rock);
      text-decoration: none;
      display: flex;
      align-items: center;
      gap: 6px;
    }
    .logo i { color: var(--dawn-orange); font-size: 2rem; }

    .nav-links {
      display: flex;
      align-items: center;
      gap: 36px;
      list-style: none;
    }
    .nav-links a {
      text-decoration: none;
      color: var(--deep-rock);
      font-weight: 500;
      position: relative;
      padding: 8px 0;
      transition: color var(--transition);
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--dawn-orange);
      transition: width var(--transition);
    }
    .nav-links a:hover { color: var(--dawn-orange); }
    .nav-links a:hover::after { width: 100%; }

    .btn-primary {
      background: var(--dawn-orange);
      color: white;
      border: none;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      letter-spacing: 0.03em;
      cursor: pointer;
      text-decoration: none;
      display: inline-block;
      transition: filter 0.2s, box-shadow var(--transition);
      box-shadow: 0 4px 10px rgba(242,122,51,0.2);
    }
    .btn-primary:hover {
      filter: brightness(1.1);
      box-shadow: 0 8px 20px rgba(242,122,51,0.35);
    }

    .btn-outline {
      background: transparent;
      border: 2px solid var(--dawn-orange);
      color: var(--dawn-orange);
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      letter-spacing: 0.03em;
      cursor: pointer;
      text-decoration: none;
      display: inline-block;
      transition: background var(--transition), color var(--transition);
    }
    .btn-outline:hover {
      background: var(--soft-orange-bg);
      color: var(--dawn-orange);
    }

    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
      background: none;
      border: none;
    }
    .hamburger span {
      width: 25px;
      height: 2px;
      background: var(--deep-rock);
      transition: var(--transition);
    }

    /* Hero */
    .hero {
      padding: 140px 0 80px;
      display: flex;
      align-items: center;
      gap: 60px;
    }
    .hero-left { flex: 1; }
    .hero-right { flex: 1; position: relative; }

    .hero h1 {
      font-size: clamp(2.5rem, 5vw, 4rem);
      font-weight: 700;
      letter-spacing: -0.02em;
      color: var(--deep-rock);
      line-height: 1.2;
      margin-bottom: 24px;
    }
    .hero-highlight {
      color: var(--dawn-orange);
      border-bottom: 3px solid var(--golden-light);
    }
    .hero-desc {
      font-size: 1.2rem;
      color: var(--shadow-blue);
      margin-bottom: 36px;
      max-width: 480px;
    }
    .hero-actions {
      display: flex;
      gap: 20px;
      flex-wrap: wrap;
    }

    .hero-graphic {
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      border-radius: 32px;
      height: 400px;
      width: 100%;
      position: relative;
      overflow: hidden;
      box-shadow: 0 25px 50px -12px rgba(0,0,0,0.15);
    }
    .hero-graphic::after {
      content: '';
      position: absolute;
      inset: 0;
      background: linear-gradient(135deg, rgba(245,247,250,0.5) 0%, rgba(255,255,255,0) 60%);
    }

    /* 通用板块 */
    .section {
      padding: var(--section-gap) 0;
    }
    .section-title {
      font-size: clamp(1.8rem, 3.5vw, 2.5rem);
      font-weight: 600;
      margin-bottom: 16px;
      color: var(--deep-rock);
    }
    .section-sub {
      color: var(--shadow-blue);
      margin-bottom: 48px;
      font-size: 1.1rem;
    }

    /* 核心优势网格 */
    .grid-3 {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .advantage-card {
      background: var(--pure-white);
      padding: 32px 24px;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
      text-align: left;
    }
    .advantage-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
    }
    .icon-circle {
      width: 48px;
      height: 48px;
      background: var(--soft-orange-bg);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      margin-bottom: 20px;
      color: var(--dawn-orange);
      font-size: 1.5rem;
    }

    /* 案例瀑布 交错 */
    .case-row {
      display: flex;
      align-items: center;
      gap: 48px;
      margin-bottom: 64px;
    }
    .case-row.reverse { flex-direction: row-reverse; }
    .case-img {
      flex: 1;
      border-radius: var(--radius-card);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
      height: 280px;
      background-size: cover;
      background-position: center;
    }
    .case-text { flex: 1; }
    .case-tag {
      color: var(--dawn-orange);
      font-weight: 600;
      letter-spacing: 0.03em;
      margin-bottom: 12px;
    }

    /* 对比表格 */
    .compare-table {
      width: 100%;
      border-collapse: collapse;
      background: white;
      border-radius: var(--radius-card);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
    }
    .compare-table th {
      background: var(--cloud-white);
      padding: 20px 24px;
      text-align: left;
      font-weight: 600;
    }
    .compare-table td {
      padding: 18px 24px;
      border-bottom: 1px solid var(--light-border);
    }
    .highlight-col {
      background: var(--soft-orange-bg);
      font-weight: 500;
    }
    .fa-check { color: #2b7a4b; }
    .fa-times { color: #adb5bd; }

    /* 数据指标 */
    .stats {
      display: flex;
      justify-content: space-around;
      flex-wrap: wrap;
      gap: 20px;
    }
    .stat-item {
      text-align: center;
    }
    .stat-number {
      font-size: 3rem;
      font-weight: 700;
      color: var(--dawn-orange);
    }

    /* FAQ */
    .faq-item {
      background: white;
      border-radius: var(--radius-card);
      margin-bottom: 16px;
      box-shadow: var(--shadow-sm);
      overflow: hidden;
    }
    .faq-question {
      padding: 20px 24px;
      font-weight: 600;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
      border-left: 4px solid transparent;
      transition: background var(--transition);
    }
    .faq-item.active .faq-question {
      border-left: 4px solid var(--dawn-orange);
      background: var(--soft-orange-bg);
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      background: #F8F9FA;
      padding: 0 24px;
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding: 20px 24px;
    }

    /* CTA 区 */
    .cta-band {
      background: linear-gradient(135deg, var(--cloud-white) 0%, var(--morning-mist) 100%);
      text-align: center;
      padding: 80px 0;
      border-radius: 32px;
      margin: 40px 0;
    }

    /* 页脚 */
    .footer {
      background: var(--deep-rock);
      color: var(--shadow-blue);
      padding: 60px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
    }
    .footer a {
      color: var(--morning-mist);
      text-decoration: none;
      transition: color var(--transition);
    }
    .footer a:hover { color: var(--dawn-orange); }

    @media (max-width: 1024px) {
      .hero { flex-direction: column; }
      .grid-3 { grid-template-columns: repeat(2,1fr); }
    }
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .hamburger { display: flex; }
      .grid-3 { grid-template-columns: 1fr; }
      .case-row, .case-row.reverse { flex-direction: column; }
      .stats { flex-direction: column; }
      .footer-grid { grid-template-columns: 1fr; }
      :root { --section-gap: 70px; }
      .hero-graphic { height: 260px; }
    }
    .mobile-menu {
      display: none;
      position: fixed;
      top: 72px;
      left: 0;
      width: 100%;
      background: var(--pure-white);
      flex-direction: column;
      padding: 24px;
      gap: 24px;
      box-shadow: 0 10px 20px rgba(0,0,0,0.05);
      z-index: 999;
    }
    .mobile-menu.active { display: flex; }