/* roulang page: index */
:root {
      --primary: #1A2B4C;
      --primary-hover: #152238;
      --accent: #D4AF37;
      --accent-hover: #B8960F;
      --bg-page: #F5F6FA;
      --bg-card: #FFFFFF;
      --text-main: #1F2329;
      --text-muted: #86909C;
      --border-light: #E5E8EF;
      --success: #00B578;
      --warning: #FF9F0A;
      --danger: #FA5151;
      --radius-card: 12px;
      --radius-btn: 8px;
      --shadow-default: 0 2px 12px rgba(26,43,76,0.06);
      --shadow-hover: 0 8px 24px rgba(26,43,76,0.12);
      --font-sans: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", system-ui, -apple-system, sans-serif;
      --max-width: 1200px;
      --padding-section: 80px;
      --gap-grid: 24px;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    body {
      font-family: var(--font-sans);
      background-color: var(--bg-page);
      color: var(--text-main);
      line-height: 1.5;
      -webkit-font-smoothing: antialiased;
    }
    .container {
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 24px;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: color 0.2s;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    button, .btn {
      cursor: pointer;
      font-family: inherit;
    }
    /* Header & Nav */
    .header {
      background: #fff;
      border-bottom: 1px solid var(--border-light);
      position: sticky;
      top: 0;
      z-index: 50;
      height: 64px;
      display: flex;
      align-items: center;
    }
    .header .container {
      display: flex;
      justify-content: space-between;
      align-items: center;
      width: 100%;
    }
    .logo {
      font-size: 24px;
      font-weight: 700;
      color: var(--primary);
      letter-spacing: 0.5px;
    }
    .logo span {
      color: var(--accent);
    }
    .nav-links {
      display: flex;
      gap: 2rem;
      align-items: center;
    }
    .nav-links a {
      font-size: 16px;
      font-weight: 500;
      color: var(--text-main);
      padding: 4px 0;
      border-bottom: 2px solid transparent;
      transition: 0.2s;
    }
    .nav-links a:hover,
    .nav-links a.active {
      color: var(--primary);
      border-bottom-color: var(--primary);
    }
    .hamburger {
      display: none;
      font-size: 24px;
      background: none;
      border: none;
      color: var(--primary);
    }
    @media (max-width: 768px) {
      .nav-links {
        position: fixed;
        top: 0;
        right: -100%;
        width: 70%;
        max-width: 300px;
        height: 100vh;
        background: #fff;
        flex-direction: column;
        padding: 80px 30px;
        gap: 2rem;
        box-shadow: -5px 0 15px rgba(0,0,0,0.1);
        transition: right 0.3s ease;
        z-index: 60;
      }
      .nav-links.active {
        right: 0;
      }
      .hamburger {
        display: block;
        position: relative;
        z-index: 70;
      }
    }
    /* Hero */
    .hero {
      background: linear-gradient(135deg, rgba(26,43,76,0.03) 0%, rgba(212,175,55,0.05) 100%);
      position: relative;
      overflow: hidden;
    }
    .hero .container {
      display: flex;
      align-items: center;
      gap: 3rem;
      padding-top: 100px;
      padding-bottom: 100px;
      flex-wrap: wrap;
    }
    .hero-text {
      flex: 1 1 400px;
    }
    .hero-text h1 {
      font-size: 36px;
      font-weight: 700;
      line-height: 1.3;
      color: var(--primary);
      margin-bottom: 1.2rem;
    }
    .hero-text p {
      font-size: 18px;
      color: var(--text-muted);
      margin-bottom: 2rem;
    }
    .hero-badge-group {
      display: flex;
      gap: 1.5rem;
      flex-wrap: wrap;
    }
    .hero-visual {
      flex: 1 1 350px;
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      min-height: 260px;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-default);
      position: relative;
    }
    .btn {
      display: inline-block;
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 16px;
      transition: all 0.2s;
      border: 1px solid transparent;
    }
    .btn-primary {
      background: var(--primary);
      color: #fff;
    }
    .btn-primary:hover {
      background: var(--primary-hover);
    }
    .btn-outline {
      background: transparent;
      border: 1px solid var(--primary);
      color: var(--primary);
    }
    .btn-outline:hover {
      background: rgba(26,43,76,0.04);
    }
    .btn-accent {
      background: var(--accent);
      color: #1A2B4C;
      font-weight: 700;
    }
    .btn-accent:hover {
      background: var(--accent-hover);
    }
    .data-badge {
      background: #fff;
      border-radius: var(--radius-card);
      padding: 16px 20px;
      box-shadow: var(--shadow-default);
      display: flex;
      align-items: center;
      gap: 12px;
    }
    .data-badge .number {
      font-size: 32px;
      font-weight: 700;
      color: var(--accent);
      line-height: 1;
    }
    .data-badge .label {
      font-size: 14px;
      color: var(--text-muted);
    }
    /* Sections */
    section {
      padding: var(--padding-section) 0;
    }
    .section-title {
      font-size: 28px;
      font-weight: 600;
      color: var(--primary);
      margin-bottom: 2rem;
      text-align: center;
    }
    /* Metrics */
    .metrics-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: var(--gap-grid);
    }
    .metric-card {
      background: var(--bg-card);
      border-radius: var(--radius-card);
      padding: 24px;
      box-shadow: var(--shadow-default);
      text-align: center;
    }
    .metric-card .big-number {
      font-size: 48px;
      font-weight: 700;
      color: var(--accent);
      line-height: 1.2;
    }
    /* Services Grid */
    .services-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: var(--gap-grid);
    }
    .service-card {
      background: var(--bg-card);
      border-radius: var(--radius-card);
      padding: 28px 24px;
      box-shadow: var(--shadow-default);
      transition: all 0.25s;
      border: 1px solid transparent;
    }
    .service-card:hover {
      box-shadow: var(--shadow-hover);
      border-color: var(--accent);
      transform: translateY(-2px);
    }
    .icon-circle {
      width: 48px;
      height: 48px;
      background: rgba(26,43,76,0.06);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      margin-bottom: 1.2rem;
      color: var(--primary);
      font-size: 22px;
    }
    /* Compare */
    .compare-row {
      display: flex;
      gap: var(--gap-grid);
      flex-wrap: wrap;
    }
    .compare-card {
      flex: 1 1 280px;
      background: #fff;
      border-radius: var(--radius-card);
      padding: 24px;
      box-shadow: var(--shadow-default);
    }
    .compare-card.highlight {
      border-left: 4px solid var(--accent);
      background: rgba(212,175,55,0.04);
    }
    /* FAQ */
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
    }
    .faq-item {
      background: #fff;
      border-radius: var(--radius-card);
      margin-bottom: 12px;
      box-shadow: var(--shadow-default);
    }
    .faq-question {
      padding: 18px 24px;
      font-weight: 600;
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
      font-size: 18px;
    }
    .faq-answer {
      padding: 0 24px 18px;
      color: var(--text-muted);
      display: none;
    }
    .faq-item.open .faq-answer {
      display: block;
    }
    /* Contact */
    .contact-panel {
      background: var(--primary);
      color: #fff;
      border-radius: var(--radius-card);
      padding: 40px;
    }
    .form-group {
      margin-bottom: 1rem;
    }
    input, textarea {
      width: 100%;
      padding: 12px 16px;
      border-radius: var(--radius-btn);
      border: 1px solid var(--border-light);
      background: #F5F6FA;
      font-size: 16px;
    }
    /* Footer */
    .footer {
      background: var(--primary);
      color: #ccc;
      padding: 40px 0 20px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr;
      gap: 2rem;
    }
    @media (max-width: 1024px) {
      .services-grid { grid-template-columns: repeat(2,1fr); }
      .metrics-grid { grid-template-columns: repeat(2,1fr); }
    }
    @media (max-width: 768px) {
      .container { padding: 0 16px; }
      .hero .container { flex-direction: column; padding-top: 60px; padding-bottom: 60px; }
      .services-grid { grid-template-columns: 1fr; }
      .metrics-grid { grid-template-columns: repeat(2,1fr); }
      .footer-grid { grid-template-columns: 1fr; }
    }