/* roulang page: index */
/* 基础变量与重置 */
    :root {
      --primary: #0A2E4D;
      --accent: #F85C3C;
      --bg-light: #F7F9FC;
      --card-bg: #FFFFFF;
      --text-main: #2C3E50;
      --text-muted: #6B8299;
      --border-light: #E2E8F0;
      --shadow-sm: 0 2px 12px rgba(10, 46, 77, 0.06);
      --shadow-md: 0 8px 28px rgba(10, 46, 77, 0.12);
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-input: 6px;
      --radius-tag: 4px;
      --font-sans: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", "Noto Sans SC", system-ui, -apple-system, sans-serif;
      --font-number: "Inter", "SF Pro Display", system-ui, sans-serif;
      --transition-smooth: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
    }

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

    html {
      scroll-behavior: smooth;
      font-size: 16px;
    }

    body {
      font-family: var(--font-sans);
      color: var(--text-main);
      background-color: var(--bg-light);
      line-height: 1.7;
      -webkit-font-smoothing: antialiased;
      -moz-osx-font-smoothing: grayscale;
    }

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

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

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

    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 20px;
    }

    /* 排版 */
    h1, h2, h3 {
      font-weight: 600;
      line-height: 1.3;
    }

    h2 {
      font-size: 2.25rem;
      text-align: center;
      position: relative;
      padding-bottom: 1rem;
    }

    h2::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 50%;
      transform: translateX(-50%);
      width: 64px;
      height: 4px;
      background: var(--accent);
      border-radius: 2px;
    }

    .section-subtitle {
      text-align: center;
      color: var(--text-muted);
      font-size: 1rem;
      margin-top: 0.75rem;
      margin-bottom: 3rem;
    }

    /* 按钮系统 */
    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      font-weight: 600;
      border-radius: var(--radius-btn);
      padding: 0.875rem 2rem;
      cursor: pointer;
      border: 2px solid transparent;
      transition: all 0.2s ease;
    }

    .btn-primary {
      background: var(--accent);
      color: white;
    }

    .btn-primary:hover {
      background: #E04A2E;
      transform: translateY(-2px);
      box-shadow: 0 6px 16px rgba(248, 92, 60, 0.4);
    }

    .btn-ghost {
      background: transparent;
      border-color: white;
      color: white;
    }

    .btn-ghost:hover {
      background: rgba(255, 255, 255, 0.15);
      transform: translateY(-2px);
    }

    .btn-text {
      background: transparent;
      border: none;
      color: var(--accent);
      font-weight: 500;
      gap: 4px;
      cursor: pointer;
    }

    .btn-text i {
      transition: transform 0.2s ease;
    }

    .btn-text:hover i {
      transform: translateX(4px);
    }

    .btn-nav-cta {
      background: var(--accent);
      color: white;
      border-radius: 50px;
      padding: 0.55rem 1.8rem;
      font-weight: 600;
      font-size: 0.9rem;
      border: none;
    }

    .btn-nav-cta:hover {
      background: #E04A2E;
    }

    /* 导航 */
    .header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 72px;
      background: white;
      z-index: 1000;
      box-shadow: none;
      transition: box-shadow 0.3s ease;
      display: flex;
      align-items: center;
    }

    .header.scrolled {
      box-shadow: 0 2px 16px rgba(0,0,0,0.06);
    }

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

    .logo {
      font-size: 1.5rem;
      font-weight: 700;
      color: var(--primary);
      display: flex;
      align-items: center;
      gap: 5px;
    }

    .logo::before {
      content: '';
      display: inline-block;
      width: 10px;
      height: 10px;
      background: var(--accent);
      margin-right: 8px;
    }

    .nav-links {
      display: flex;
      align-items: center;
      gap: 2rem;
    }

    .nav-links a {
      font-size: 0.95rem;
      font-weight: 500;
      color: var(--text-main);
      position: relative;
      padding: 5px 0;
    }

    .nav-links a:hover,
    .nav-links a.active {
      color: var(--accent);
    }

    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: -2px;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--accent);
      transition: width 0.2s ease;
    }

    .nav-links a:hover::after {
      width: 100%;
    }

    .menu-toggle {
      display: none;
      flex-direction: column;
      gap: 5px;
      background: none;
      border: none;
      cursor: pointer;
      padding: 8px;
    }

    .menu-toggle span {
      width: 24px;
      height: 2px;
      background: var(--primary);
      transition: 0.3s;
    }

    .mobile-menu {
      position: fixed;
      top: 0;
      right: 0;
      width: 280px;
      height: 100vh;
      background: white;
      box-shadow: -5px 0 20px rgba(0,0,0,0.1);
      transform: translateX(100%);
      transition: transform 0.3s ease;
      z-index: 1001;
      padding: 80px 30px 30px;
      display: flex;
      flex-direction: column;
      gap: 1.8rem;
    }

    .mobile-menu.open {
      transform: translateX(0);
    }

    .mobile-menu a {
      font-size: 1.2rem;
      font-weight: 500;
    }

    /* Hero */
    .hero {
      min-height: 100vh;
      width: 100%;
      background: linear-gradient(135deg, rgba(10,46,77,0.88) 0%, rgba(10,46,77,0.7) 100%), url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      display: flex;
      align-items: center;
      justify-content: center;
      text-align: center;
      color: white;
      position: relative;
      margin-top: 0;
    }

    .hero-content {
      max-width: 780px;
      padding: 20px;
    }

    .hero h1 {
      font-size: 3rem;
      font-weight: 700;
      margin-bottom: 1rem;
      line-height: 1.3;
    }

    .hero-sub {
      font-size: 1.2rem;
      opacity: 0.9;
      margin-bottom: 2.5rem;
    }

    .hero-buttons {
      display: flex;
      gap: 18px;
      justify-content: center;
      flex-wrap: wrap;
    }

    .hero-floating-card {
      position: absolute;
      bottom: 15%;
      right: 8%;
      background: rgba(255,255,255,0.12);
      backdrop-filter: blur(14px);
      -webkit-backdrop-filter: blur(14px);
      border-radius: var(--radius-card);
      padding: 1.3rem 2rem;
      color: white;
      border: 1px solid rgba(255,255,255,0.2);
    }

    .scroll-down {
      position: absolute;
      bottom: 25px;
      left: 50%;
      transform: translateX(-50%);
      font-size: 1.8rem;
      animation: bounce 2s infinite;
      color: white;
      opacity: 0.8;
    }

    @keyframes bounce {
      0%,100%{transform:translateY(0);}
      50%{transform:translateY(8px);}
    }

    /* 板块通用 */
    .section {
      padding: 5rem 0;
    }

    @media (max-width: 768px) {
      .section {
        padding: 3.5rem 0;
      }
      .hero h1 {
        font-size: 2rem;
      }
    }

    /* 数据看板 */
    .dashboard-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
    }

    .stat-card {
      background: var(--card-bg);
      border-radius: var(--radius-card);
      padding: 2rem 1rem;
      text-align: center;
      box-shadow: var(--shadow-sm);
      border: 1px solid var(--border-light);
      transition: var(--transition-smooth);
    }

    .stat-number {
      font-family: var(--font-number);
      font-size: 2.6rem;
      font-weight: 700;
      color: var(--accent);
    }

    .stat-label {
      color: var(--text-muted);
      font-size: 0.9rem;
    }

    /* 服务 */
    .services-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }

    .service-card {
      background: var(--card-bg);
      padding: 1.8rem;
      border-radius: var(--radius-card);
      border: 1px solid var(--border-light);
      box-shadow: var(--shadow-sm);
      transition: all 0.3s ease;
    }

    .service-card:hover {
      transform: translateY(-8px);
      box-shadow: var(--shadow-md);
      border-color: rgba(10,46,77,0.2);
    }

    .service-img {
      width: 80px;
      height: 80px;
      background: #F0F4F8;
      border-radius: 12px;
      margin-bottom: 1.2rem;
      display: flex;
      align-items: center;
      justify-content: center;
    }

    .tags {
      display: flex;
      flex-wrap: wrap;
      gap: 6px;
      margin: 0.8rem 0;
    }

    .tag {
      background: #F0F4F8;
      color: var(--primary);
      font-size: 0.75rem;
      padding: 0.25rem 0.8rem;
      border-radius: 20px;
      font-weight: 500;
    }

    /* 案例对比 */
    .case-row {
      display: flex;
      gap: 30px;
    }

    .case-col {
      flex:1;
      background: var(--card-bg);
      border-radius: var(--radius-card);
      padding: 2.2rem;
    }

    .case-pain { background: #FFF5F5; }
    .case-solution { background: #F0FAF5; }

    .vs-badge {
      display: flex;
      align-items: center;
      justify-content: center;
      width: 56px;
      height: 56px;
      background: var(--accent);
      color: white;
      border-radius: 50%;
      font-weight: bold;
      align-self: center;
    }

    /* FAQ */
    .faq-item {
      border-bottom: 1px solid var(--border-light);
      background: white;
      border-radius: 8px;
      margin-bottom: 8px;
    }
    .faq-question {
      padding: 1.2rem 1.5rem;
      font-weight: 600;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      background: #F9FBFC;
      padding: 0 1.5rem;
    }
    .faq-item.active .faq-answer {
      max-height: 180px;
      padding: 1rem 1.5rem;
    }

    /* 表单 */
    .cta-section {
      background: linear-gradient(135deg, #0A2E4D 0%, #1A4A6E 100%);
    }
    .form-card {
      background: white;
      border-radius: var(--radius-card);
      padding: 2.2rem;
    }
    .input-field {
      width: 100%;
      padding: 0.8rem;
      border: 1px solid var(--border-light);
      border-radius: var(--radius-input);
      margin-bottom: 1rem;
    }

    /* 页脚 */
    .footer {
      background: var(--primary);
      color: #B0C4D8;
      padding: 2.5rem 0 1rem;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 2rem;
    }
    .copyright {
      border-top: 1px solid rgba(255,255,255,0.15);
      padding-top: 1.5rem;
      margin-top: 1.5rem;
      text-align: center;
      font-size: 0.85rem;
    }

    @media (max-width: 1024px) {
      .services-grid { grid-template-columns: repeat(2,1fr); }
      .dashboard-grid { grid-template-columns: repeat(2,1fr); }
    }
    @media (max-width: 768px) {
      .menu-toggle { display: flex; }
      .nav-links { display: none; }
      .dashboard-grid { grid-template-columns: 1fr 1fr; }
      .services-grid { grid-template-columns: 1fr; }
      .case-row { flex-direction: column; }
      .vs-badge { align-self: center; transform: rotate(90deg); }
      .footer-grid { grid-template-columns: 1fr 1fr; }
    }