/* roulang page: index */
:root {
      --primary: #D94E2B;
      --primary-hover: #C14422;
      --secondary: #3B2C24;
      --accent: #C8964E;
      --bg: #FAF7F4;
      --card-bg: #FFFFFF;
      --alt-bg: #FDF9F5;
      --text-main: #3B2C24;
      --text-body: #4A4040;
      --text-muted: #8C7E78;
      --text-inverse: #FAF7F4;
      --border-light: #D6CFC8;
      --chip-bg: #F0EBE8;
      --shadow-sm: 0 2px 16px rgba(59,44,36,0.06);
      --shadow-md: 0 8px 28px rgba(59,44,36,0.12);
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-chip: 20px;
      --font-serif: "Noto Serif SC", "Songti SC", "SimSun", "STSong", serif;
      --font-sans: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Helvetica, Arial, sans-serif;
      --font-mono: "SF Mono", "Menlo", "Consolas", "Courier New", monospace;
      --transition: 0.25s ease;
    }

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

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

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

    h1, h2, h3, h4 {
      font-family: var(--font-serif);
      color: var(--text-main);
      font-weight: 700;
      line-height: 1.25;
    }

    h1 {
      font-size: 48px;
      letter-spacing: 0.5px;
    }

    h2 {
      font-size: 38px;
      margin-bottom: 24px;
      position: relative;
      display: inline-block;
    }

    h2::after {
      content: '';
      position: absolute;
      left: 0;
      bottom: -8px;
      width: 56px;
      height: 3px;
      background: var(--primary);
      border-radius: 2px;
    }

    h3 {
      font-size: 22px;
      margin-bottom: 12px;
    }

    h4 {
      font-family: var(--font-sans);
      font-size: 18px;
      font-weight: 600;
      color: var(--text-main);
    }

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

    a:hover {
      color: var(--primary-hover);
      text-decoration: none;
    }

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

    button, .button {
      font-family: var(--font-sans);
      border-radius: var(--radius-btn);
      padding: 14px 32px;
      font-weight: 600;
      font-size: 15px;
      letter-spacing: 0.3px;
      cursor: pointer;
      transition: all var(--transition);
      display: inline-block;
      text-align: center;
      line-height: 1.4;
      border: none;
    }

    .btn-primary {
      background: var(--primary);
      color: white;
      box-shadow: 0 4px 12px rgba(217,78,43,0.25);
    }

    .btn-primary:hover {
      background: var(--primary-hover);
      box-shadow: 0 6px 18px rgba(217,78,43,0.35);
      transform: translateY(-1px);
      color: white;
    }

    .btn-outline {
      background: transparent;
      border: 1.5px solid var(--primary);
      color: var(--primary);
      padding: 13px 31px;
    }

    .btn-outline:hover {
      background: rgba(217,78,43,0.08);
      border-color: var(--primary-hover);
      color: var(--primary-hover);
      transform: translateY(-1px);
    }

    .chip {
      display: inline-block;
      background: var(--chip-bg);
      color: var(--secondary);
      padding: 8px 18px;
      border-radius: var(--radius-chip);
      font-size: 14px;
      font-weight: 500;
      transition: all var(--transition);
      cursor: pointer;
      white-space: nowrap;
    }

    .chip.active {
      background: var(--primary);
      color: white;
    }

    .chip:hover:not(.active) {
      background: #e8e0da;
    }

    .card {
      background: var(--card-bg);
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-sm);
      transition: all 0.3s ease;
      overflow: hidden;
      height: 100%;
      display: flex;
      flex-direction: column;
    }

    .card:hover {
      box-shadow: var(--shadow-md);
      transform: translateY(-6px);
    }

    .card-image {
      overflow: hidden;
      border-radius: var(--radius-card) var(--radius-card) 0 0;
    }

    .card-image img {
      transition: transform 0.4s ease;
      width: 100%;
      height: 220px;
      object-fit: cover;
    }

    .card:hover .card-image img {
      transform: scale(1.04);
    }

    .card-body {
      padding: 28px 28px 24px;
      flex: 1;
      display: flex;
      flex-direction: column;
    }

    .card-body p {
      color: var(--text-muted);
      font-size: 15px;
      line-height: 1.7;
      margin-bottom: 18px;
      flex: 1;
    }

    .section-padding {
      padding: 90px 0;
    }

    .bg-alt {
      background: var(--alt-bg);
    }

    .text-muted {
      color: var(--text-muted);
    }

    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 32px;
      text-align: center;
    }

    .stat-number {
      font-family: var(--font-mono);
      font-size: 42px;
      font-weight: 700;
      color: var(--primary);
      line-height: 1.1;
    }

    .stat-label {
      font-size: 15px;
      color: var(--text-muted);
      margin-top: 8px;
      font-weight: 500;
      letter-spacing: 0.5px;
    }

    .gold-divider {
      width: 100%;
      height: 1px;
      background: rgba(200,150,78,0.25);
      margin: 40px 0;
    }

    .faq-item {
      border-bottom: 1px solid var(--border-light);
      padding: 24px 0;
      cursor: pointer;
    }

    .faq-question {
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-weight: 600;
      color: var(--secondary);
      transition: color var(--transition);
    }

    .faq-question i {
      transition: transform 0.3s ease;
      color: var(--primary);
      font-size: 18px;
    }

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease, padding 0.2s ease;
      color: var(--text-body);
      line-height: 1.8;
      padding-right: 20px;
    }

    .faq-item.active .faq-question {
      color: var(--primary);
    }

    .faq-item.active .faq-answer {
      max-height: 400px;
      padding-top: 16px;
    }

    .faq-item.active .faq-question i {
      transform: rotate(180deg);
    }

    .form-input {
      border: 1px solid var(--border-light);
      border-radius: 8px;
      padding: 14px 18px;
      font-size: 15px;
      background: white;
      transition: border 0.2s, box-shadow 0.2s;
      width: 100%;
      margin-bottom: 18px;
    }

    .form-input:focus {
      outline: none;
      border-color: var(--primary);
      box-shadow: 0 0 0 3px rgba(217,78,43,0.15);
    }

    footer {
      background: var(--secondary);
      color: rgba(250,247,244,0.8);
      padding: 60px 0 30px;
    }

    footer a {
      color: rgba(250,247,244,0.9);
    }

    footer a:hover {
      color: var(--accent);
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
    }

    @media (max-width: 1024px) {
      h1 { font-size: 40px; }
      h2 { font-size: 32px; }
      .stats-grid { grid-template-columns: repeat(2, 1fr); gap: 24px; }
      .footer-grid { grid-template-columns: 1fr 1fr; }
    }

    @media (max-width: 768px) {
      h1 { font-size: 34px; }
      h2 { font-size: 28px; }
      .section-padding { padding: 56px 0; }
      .container { padding: 0 20px; }
      .stats-grid { gap: 20px; }
      .stat-number { font-size: 32px; }
      .footer-grid { grid-template-columns: 1fr; gap: 28px; }
    }

    .top-bar, .title-bar {
      background: white;
      box-shadow: 0 1px 8px rgba(0,0,0,0.04);
      padding: 12px 0;
    }

    .menu li a {
      color: var(--secondary);
      font-weight: 500;
      font-size: 15px;
      padding: 8px 12px;
    }

    .menu .active > a {
      background: var(--primary);
      color: white;
      border-radius: 20px;
      padding: 6px 16px;
    }

    .hero-bg {
      background: radial-gradient(circle at 80% 20%, rgba(217,78,43,0.06) 0%, transparent 60%);
    }

    .comparison-bar {
      background: var(--chip-bg);
      border-radius: 20px;
      height: 12px;
      width: 100%;
      margin: 8px 0;
      position: relative;
    }

    .comparison-fill {
      background: var(--primary);
      height: 12px;
      border-radius: 20px;
      width: 0%;
      transition: width 1s ease;
    }