/* roulang page: index */
:root {
      --primary: #F04E30;
      --primary-dark: #E63C1E;
      --secondary: #1E1E2A;
      --accent: #FFB800;
      --bg-light: #F7F7FA;
      --white: #FFFFFF;
      --text-dark: #2D2D3A;
      --text-muted: #6F6F7A;
      --text-light: #B0B0C0;
      --border-light: #E8E8EE;
      --shadow-card: 0 4px 20px rgba(0,0,0,0.04);
      --shadow-hover: 0 8px 30px rgba(0,0,0,0.08);
      --radius-lg: 16px;
      --radius-md: 12px;
      --radius-btn: 8px;
      --font-family: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
      --section-gap: 88px;
      --nav-height: 72px;
    }

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

    html {
      scroll-behavior: smooth;
      scroll-padding-top: var(--nav-height);
    }

    body {
      font-family: var(--font-family);
      font-weight: 400;
      font-size: 16px;
      line-height: 1.7;
      background-color: var(--bg-light);
      color: var(--text-dark);
      -webkit-font-smoothing: antialiased;
      text-rendering: optimizeLegibility;
    }

    a, button, input {
      font-family: inherit;
    }

    a {
      text-decoration: none;
      color: inherit;
      transition: color 0.2s;
    }

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

    .container {
      max-width: 1280px;
      margin-left: auto;
      margin-right: auto;
      padding-left: 32px;
      padding-right: 32px;
    }

    /* 导航 */
    .site-header {
      position: sticky;
      top: 0;
      z-index: 50;
      background: var(--white);
      height: var(--nav-height);
      box-shadow: 0 2px 12px rgba(0,0,0,0.04);
      display: flex;
      align-items: center;
    }

    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
    }

    .brand {
      font-size: 22px;
      font-weight: 700;
      color: var(--secondary);
      white-space: nowrap;
      letter-spacing: -0.3px;
    }
    .brand span {
      color: var(--primary);
    }
    .brand a {
      color: inherit;
    }

    .nav-links {
      display: flex;
      align-items: center;
      gap: 36px;
      list-style: none;
    }

    .nav-links a {
      font-weight: 500;
      color: var(--text-dark);
      font-size: 15px;
      position: relative;
      padding-bottom: 6px;
      transition: color 0.2s;
    }

    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0%;
      height: 2px;
      background: var(--primary);
      transition: width 0.25s ease;
    }
    .nav-links a:hover {
      color: var(--primary);
    }
    .nav-links a:hover::after {
      width: 100%;
    }

    .btn-primary {
      background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
      color: var(--white);
      font-weight: 600;
      border-radius: var(--radius-btn);
      padding: 10px 24px;
      display: inline-flex;
      align-items: center;
      gap: 8px;
      transition: all 0.2s ease;
      border: none;
      cursor: pointer;
      white-space: nowrap;
      box-shadow: 0 4px 12px rgba(240,78,48,0.2);
    }
    .btn-primary:hover {
      filter: brightness(1.1);
      box-shadow: 0 6px 18px rgba(240,78,48,0.3);
      transform: translateY(-1px);
    }

    .btn-outline {
      background: transparent;
      border: 2px solid var(--white);
      color: var(--white);
      font-weight: 600;
      border-radius: var(--radius-btn);
      padding: 12px 32px;
      transition: all 0.25s;
      cursor: pointer;
    }
    .btn-outline:hover {
      background: rgba(255,255,255,0.1);
      border-color: var(--white);
    }
    .btn-outline-dark {
      border-color: var(--primary);
      color: var(--primary);
      background: transparent;
      font-weight: 600;
      border-radius: var(--radius-btn);
      padding: 12px 32px;
      cursor: pointer;
      transition: background 0.2s;
    }
    .btn-outline-dark:hover {
      background: rgba(240,78,48,0.06);
    }

    .hamburger {
      display: none;
      background: none;
      border: none;
      font-size: 26px;
      color: var(--secondary);
      cursor: pointer;
    }

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

    .section-title {
      font-size: 36px;
      font-weight: 700;
      line-height: 1.3;
      margin-bottom: 16px;
      color: var(--secondary);
    }
    .section-sub {
      font-size: 18px;
      color: var(--text-muted);
      margin-bottom: 48px;
      max-width: 600px;
    }

    /* Hero */
    .hero {
      background: var(--secondary);
      color: var(--white);
      padding-top: 64px;
      padding-bottom: 64px;
    }
    .hero-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 48px;
      align-items: center;
    }
    .hero-left h1 {
      font-size: 48px;
      font-weight: 700;
      line-height: 1.2;
      margin-bottom: 20px;
    }
    .hero-left .hero-sub {
      font-size: 18px;
      color: rgba(255,255,255,0.8);
      margin-bottom: 32px;
    }
    .hero-buttons {
      display: flex;
      flex-wrap: wrap;
      gap: 16px;
    }
    .hero-image {
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      background-color: #2a2a38;
      border-radius: var(--radius-lg);
      aspect-ratio: 4 / 3;
      box-shadow: 0 20px 40px rgba(0,0,0,0.3);
    }

    /* 卡片网格 */
    .grid-4, .grid-3 {
      display: grid;
      gap: 24px;
    }
    .grid-4 { grid-template-columns: repeat(4, 1fr); }
    .grid-3 { grid-template-columns: repeat(3, 1fr); }

    .card {
      background: var(--white);
      border-radius: var(--radius-lg);
      padding: 32px;
      box-shadow: var(--shadow-card);
      transition: transform 0.3s, box-shadow 0.3s;
      display: flex;
      flex-direction: column;
    }
    .card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
    }
    .icon-box {
      width: 64px;
      height: 64px;
      background: rgba(255,184,0,0.12);
      border-radius: var(--radius-md);
      display: flex;
      align-items: center;
      justify-content: center;
      color: var(--accent);
      font-size: 28px;
      margin-bottom: 24px;
    }
    .card h3 {
      font-size: 22px;
      font-weight: 700;
      margin-bottom: 12px;
    }
    .card p {
      font-size: 16px;
      color: var(--text-muted);
      line-height: 1.7;
    }

    .stats-band {
      display: flex;
      justify-content: space-between;
      flex-wrap: wrap;
      gap: 32px;
      text-align: center;
    }
    .stat-item {
      flex: 1;
      min-width: 160px;
    }
    .stat-number {
      font-size: 40px;
      font-weight: 800;
      color: var(--primary);
      line-height: 1.1;
    }
    .stat-label {
      font-size: 14px;
      color: var(--text-muted);
      margin-top: 8px;
    }

    .case-img {
      aspect-ratio: 16 / 9;
      background-size: cover;
      background-position: center;
      border-radius: var(--radius-md);
      margin-bottom: 20px;
    }

    /* FAQ */
    .faq-list {
      display: flex;
      flex-direction: column;
      gap: 12px;
      max-width: 860px;
      margin: 0 auto;
    }
    .faq-item {
      background: var(--white);
      border-radius: var(--radius-md);
      box-shadow: var(--shadow-card);
      overflow: hidden;
    }
    .faq-question {
      background: var(--bg-light);
      padding: 16px 24px;
      font-weight: 600;
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
      transition: color 0.2s;
    }
    .faq-question:hover {
      color: var(--primary);
    }
    .faq-icon {
      transition: transform 0.3s;
      font-size: 18px;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.35s ease, padding 0.3s;
      background: var(--white);
      padding: 0 24px;
      color: var(--text-dark);
    }
    .faq-item.open .faq-answer {
      max-height: 200px;
      padding: 16px 24px;
    }
    .faq-item.open .faq-icon {
      transform: rotate(45deg);
    }

    /* CTA 尾板 */
    .cta-band {
      background: var(--primary);
      color: var(--white);
      text-align: center;
    }
    .cta-band h2 {
      font-size: 36px;
      font-weight: 700;
      margin-bottom: 16px;
    }
    .cta-band p {
      font-size: 18px;
      margin-bottom: 32px;
      opacity: 0.9;
    }

    .footer {
      background: var(--secondary);
      color: var(--text-light);
      padding: 32px 0;
      font-size: 14px;
    }
    .footer-inner {
      display: flex;
      justify-content: space-between;
      align-items: center;
      flex-wrap: wrap;
      gap: 16px;
    }
    .footer a {
      color: var(--text-light);
      margin-left: 24px;
    }
    .footer a:hover {
      color: var(--primary);
    }

    @media (max-width: 1024px) {
      .grid-4 { grid-template-columns: repeat(2, 1fr); }
      .hero-grid { grid-template-columns: 1fr; }
      .hero-image { max-width: 400px; margin: 0 auto; }
    }
    @media (max-width: 768px) {
      .container { padding-left: 20px; padding-right: 20px; }
      .nav-links { display: none; }
      .hamburger { display: block; }
      .mobile-menu {
        display: none;
        position: absolute;
        top: var(--nav-height);
        left: 0;
        width: 100%;
        background: var(--secondary);
        flex-direction: column;
        padding: 24px;
        gap: 16px;
      }
      .mobile-menu.active { display: flex; }
      .mobile-menu a {
        color: var(--white);
        font-size: 18px;
        font-weight: 500;
      }
      .grid-4, .grid-3 { grid-template-columns: 1fr; }
      .stats-band { flex-direction: column; align-items: center; }
      .footer-inner { flex-direction: column; text-align: center; }
      .hero-left h1 { font-size: 36px; }
      .section-title { font-size: 28px; }
    }