/* roulang page: index */
:root {
      --primary-deep: #1A2A3A;
      --accent-orange: #E85D04;
      --accent-orange-hover: #D14D00;
      --bg-light: #F8F9FA;
      --bg-white: #FFFFFF;
      --text-body: #4A4A4A;
      --text-muted: #6B7280;
      --border-light: #E5E7EB;
      --border-input: #D1D5DB;
      --shadow-sm: 0 2px 8px rgba(26,42,58,0.06);
      --shadow-hover: 0 8px 24px rgba(26,42,58,0.12);
      --radius-card: 8px;
      --radius-btn: 4px;
      --font-family: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
      --transition-smooth: all 0.25s ease;
    }

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

    body {
      font-family: var(--font-family);
      background-color: var(--bg-light);
      color: var(--text-body);
      line-height: 1.7;
      font-weight: 400;
      font-size: 1rem;
      -webkit-font-smoothing: antialiased;
      overflow-x: hidden;
    }

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

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

    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }

    /* 导航栏 */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      background: rgba(255,255,255,0.97);
      backdrop-filter: blur(8px);
      border-bottom: 1px solid transparent;
      transition: background 0.3s, box-shadow 0.3s, border-color 0.3s;
    }

    .site-header.scrolled {
      box-shadow: 0 2px 12px rgba(0,0,0,0.05);
      border-bottom: 1px solid var(--border-light);
    }

    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
      height: 70px;
      position: relative;
    }

    .logo-area {
      font-size: 1.6rem;
      font-weight: 700;
      color: var(--primary-deep);
      letter-spacing: 1px;
      display: flex;
      align-items: center;
      gap: 8px;
    }
    .logo-icon {
      color: var(--accent-orange);
      font-size: 2rem;
    }

    .desktop-nav {
      display: flex;
      align-items: center;
      gap: 28px;
    }

    .nav-left, .nav-right {
      display: flex;
      gap: 20px;
    }

    .desktop-nav a {
      color: var(--primary-deep);
      font-weight: 500;
      font-size: 0.95rem;
      padding: 6px 0;
      border-bottom: 2px solid transparent;
    }

    .desktop-nav a:hover,
    .desktop-nav a.active {
      color: var(--accent-orange);
      border-bottom-color: var(--accent-orange);
    }

    .mobile-toggle {
      display: none;
      background: none;
      border: none;
      font-size: 1.8rem;
      color: var(--primary-deep);
      cursor: pointer;
    }

    /* 移动端菜单 */
    .mobile-menu {
      display: none;
      position: fixed;
      top: 70px;
      left: 0;
      width: 100%;
      background: var(--primary-deep);
      padding: 30px 24px;
      flex-direction: column;
      gap: 18px;
      z-index: 999;
      box-shadow: 0 15px 25px rgba(0,0,0,0.15);
    }

    .mobile-menu a {
      color: #FFFFFF;
      font-size: 1.1rem;
      font-weight: 500;
      border-bottom: 1px solid rgba(255,255,255,0.15);
      padding-bottom: 8px;
    }

    .mobile-menu a:hover {
      color: var(--accent-orange);
    }

    /* Hero */
    .hero {
      padding: 120px 0 80px;
      background-color: var(--bg-light);
      display: flex;
      align-items: center;
      min-height: 85vh;
    }

    .hero-grid {
      display: flex;
      align-items: center;
      gap: 50px;
    }

    .hero-text {
      flex: 1 1 55%;
    }

    .hero-text h1 {
      font-size: 2.8rem;
      font-weight: 700;
      color: var(--primary-deep);
      line-height: 1.3;
      margin-bottom: 20px;
    }
    .hero-text h1 span {
      color: var(--accent-orange);
    }

    .hero-sub {
      font-size: 1.15rem;
      color: var(--text-muted);
      margin-bottom: 32px;
      max-width: 500px;
    }

    .btn-primary {
      background: var(--accent-orange);
      color: #FFFFFF;
      font-weight: 600;
      padding: 14px 34px;
      border-radius: var(--radius-btn);
      display: inline-block;
      border: none;
      cursor: pointer;
      transition: 0.2s ease;
      font-size: 1rem;
    }

    .btn-primary:hover {
      background: var(--accent-orange-hover);
      transform: scale(1.03);
      color: #fff;
    }

    .hero-image {
      flex: 1 1 45%;
      background: #E5E7EB;
      border-radius: 16px;
      overflow: hidden;
      min-height: 320px;
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      box-shadow: 0 20px 30px rgba(0,0,0,0.1);
    }

    /* 通用区块 */
    .section {
      padding: 70px 0;
    }

    .section-title {
      text-align: center;
      margin-bottom: 48px;
    }
    .section-title h2 {
      font-size: 2rem;
      font-weight: 700;
      color: var(--primary-deep);
      margin-bottom: 10px;
    }
    .section-title p {
      color: var(--text-muted);
      font-size: 1rem;
      max-width: 600px;
      margin: 0 auto;
    }

    /* 核心优势卡片 */
    .card-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }

    .advantage-card {
      background: var(--bg-white);
      padding: 28px 24px;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-sm);
      transition: var(--transition-smooth);
      border-left: 4px solid transparent;
    }
    .advantage-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-hover);
      border-left-color: var(--accent-orange);
    }
    .advantage-icon {
      font-size: 2.2rem;
      color: var(--accent-orange);
      margin-bottom: 18px;
    }
    .advantage-card h3 {
      font-size: 1.25rem;
      font-weight: 700;
      color: var(--primary-deep);
    }

    /* 服务卡片 */
    .service-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }

    .service-card {
      background: #fff;
      border-radius: var(--radius-card);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
      transition: var(--transition-smooth);
      border: 1px solid var(--border-light);
    }
    .service-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
    }
    .card-img {
      height: 180px;
      background-color: #E5E7EB;
      background-size: cover;
      background-position: center;
    }
    .card-content {
      padding: 20px;
    }
    .card-content h4 {
      font-weight: 700;
      color: var(--primary-deep);
    }

    /* 数据背书深色区 */
    .dark-stats {
      background: var(--primary-deep);
      padding: 70px 0;
      color: #fff;
    }
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      text-align: center;
      gap: 20px;
    }
    .stat-number {
      font-size: 2.6rem;
      font-weight: 700;
      color: var(--accent-orange);
    }

    /* 案例卡片 */
    .case-card {
      display: flex;
      background: #fff;
      border: 1px solid var(--border-light);
      border-radius: var(--radius-card);
      overflow: hidden;
      margin-bottom: 24px;
      transition: 0.2s;
    }
    .case-card:hover {
      border-color: var(--accent-orange);
    }
    .case-img {
      width: 40%;
      background: #E5E7EB;
      min-height: 220px;
      background-size: cover;
      background-position: center;
    }
    .case-info {
      padding: 28px;
      width: 60%;
    }

    /* 流程 */
    .process-list {
      max-width: 800px;
      margin: 0 auto;
    }
    .process-item {
      display: flex;
      gap: 24px;
      margin-bottom: 32px;
      align-items: flex-start;
    }
    .process-num {
      background: var(--accent-orange);
      color: #fff;
      width: 48px;
      height: 48px;
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 700;
      font-size: 1.3rem;
      flex-shrink: 0;
    }

    /* FAQ */
    .accordion-item {
      background: #fff;
      border-radius: 8px;
      margin-bottom: 12px;
      border: 1px solid var(--border-light);
    }
    .accordion-question {
      background: #F8F9FA;
      padding: 16px 20px;
      font-weight: 600;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
    }
    .accordion-answer {
      padding: 0 20px 16px;
      display: none;
      color: var(--text-body);
    }
    .accordion-answer.show {
      display: block;
    }

    /* CTA */
    .cta-block {
      background: #F0F2F5;
    }
    .form-input {
      border: 1px solid var(--border-input);
      border-radius: 4px;
      padding: 12px;
      width: 100%;
      margin-bottom: 16px;
    }
    .form-input:focus {
      border-color: var(--accent-orange);
      outline: none;
    }

    .footer {
      background: var(--primary-deep);
      color: #ddd;
      padding: 50px 0 20px;
    }

    @media (max-width: 1024px) {
      .desktop-nav { display: none; }
      .mobile-toggle { display: block; }
      .hero-grid { flex-direction: column; }
      .card-grid, .service-grid { grid-template-columns: repeat(2,1fr); }
    }

    @media (max-width: 640px) {
      .card-grid, .service-grid, .stats-grid { grid-template-columns: 1fr; }
      .case-card { flex-direction: column; }
      .case-img { width: 100%; height: 200px; }
      .case-info { width: 100%; }
      .hero-text h1 { font-size: 2rem; }
    }