:root {
      --bg-main: #f1f4ff;
      --bg-card: #ffffff;
      --text-main: #0f172a;
      --text-muted: #475569;
      --text-sub: #64748b;
      --accent-primary: #6366f1;
      --accent-subtle: #e0e7ff;
      --accent-navy: #312e81;
      --accent-gold: #b45309;
      --border-subtle: rgba(15, 23, 42, 0.08);
      --card-radius: 20px;
      --shadow-sm: 0 4px 14px rgba(15, 23, 42, 0.04);
      --shadow-md: 0 10px 28px rgba(15, 23, 42, 0.06);
      --shadow-lg: 0 20px 45px rgba(15, 23, 42, 0.09);
      --transition: all 0.35s cubic-bezier(0.16, 1, 0.3, 1);
    }

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

    body {
      background-color: var(--bg-main);
      color: var(--text-main);
      font-family: 'Plus Jakarta Sans', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
      line-height: 1.6;
      -webkit-font-smoothing: antialiased;
      padding: 40px 20px 90px;
    }

    .container {
      max-width: 1260px;
      margin: 0 auto;
    }

    /* Header Section */
    .header-section {
      text-align: center;
      padding: 30px 20px 40px;
      max-width: 920px;
      margin: 0 auto;
    }

    .badge {
      display: inline-block;
      padding: 6px 18px;
      background: #ffffff;
      color: var(--accent-navy);
      font-size: 13px;
      font-weight: 700;
      text-transform: uppercase;
      letter-spacing: 1.2px;
      border-radius: 999px;
      border: 1px solid rgba(99, 102, 241, 0.22);
      box-shadow: var(--shadow-sm);
      margin-bottom: 18px;
    }

    .page-title {
      font-family: 'Space Grotesk', sans-serif;
      font-size: clamp(32px, 4.8vw, 50px);
      font-weight: 700;
      line-height: 1.18;
      letter-spacing: -0.02em;
      color: var(--text-main);
      margin-bottom: 16px;
    }

    .page-subtitle {
      font-size: clamp(15px, 2.2vw, 18px);
      color: var(--text-muted);
      font-weight: 400;
      max-width: 780px;
      margin: 0 auto;
    }

    /* Key Highlights Row */
    .highlights-row {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 16px;
      margin: 30px 0 55px;
    }

    .highlight-card {
      background: var(--bg-card);
      border: 1px solid var(--border-subtle);
      border-radius: 16px;
      padding: 22px 18px;
      text-align: center;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
    }

    .highlight-card:hover {
      transform: translateY(-3px);
      box-shadow: var(--shadow-md);
      border-color: rgba(99, 102, 241, 0.3);
    }

    .highlight-icon {
      font-size: 26px;
      margin-bottom: 8px;
      display: inline-block;
    }

    .highlight-title {
      font-size: 15px;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 4px;
    }

    .highlight-desc {
      font-size: 12.5px;
      color: var(--text-sub);
      line-height: 1.45;
    }

    /* Chapter Section */
    .chapter-section {
      margin-bottom: 60px;
    }

    .chapter-header {
      display: flex;
      justify-content: space-between;
      align-items: flex-end;
      padding-bottom: 14px;
      border-bottom: 2px solid rgba(15, 23, 42, 0.08);
      margin-bottom: 26px;
    }

    .chapter-title-group {
      display: flex;
      flex-direction: column;
      gap: 4px;
    }

    .chapter-tag {
      font-size: 12px;
      font-weight: 800;
      color: var(--accent-primary);
      text-transform: uppercase;
      letter-spacing: 1.5px;
    }

    .chapter-title {
      font-family: 'Space Grotesk', sans-serif;
      font-size: clamp(22px, 3vw, 28px);
      font-weight: 700;
      letter-spacing: -0.01em;
      color: var(--text-main);
    }

    .chapter-count {
      font-size: 13px;
      font-weight: 600;
      color: var(--text-sub);
      background: rgba(255, 255, 255, 0.8);
      padding: 4px 12px;
      border-radius: 999px;
      border: 1px solid var(--border-subtle);
    }

    /* Responsive Grids */
    .grid-4-col {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 22px;
    }

    /* Card Base */
    .card-base {
      background: var(--bg-card);
      border: 1px solid var(--border-subtle);
      border-radius: var(--card-radius);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
      display: flex;
      flex-direction: column;
      transition: var(--transition);
    }

    .card-base:hover {
      transform: translateY(-5px);
      box-shadow: var(--shadow-lg);
      border-color: rgba(99, 102, 241, 0.35);
    }

    .image-box {
      position: relative;
      width: 100%;
      aspect-ratio: 1 / 1;
      background: #f1f4ff;
      overflow: hidden;
    }

    .image-box img {
      width: 100%;
      height: 100%;
      object-fit: cover;
      display: block;
      transition: transform 0.6s cubic-bezier(0.16, 1, 0.3, 1);
    }

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

    .card-badge {
      position: absolute;
      top: 14px;
      left: 14px;
      background: rgba(15, 23, 42, 0.75);
      backdrop-filter: blur(8px);
      -webkit-backdrop-filter: blur(8px);
      color: #ffffff;
      font-size: 11.5px;
      font-weight: 600;
      padding: 4px 12px;
      border-radius: 999px;
      letter-spacing: 0.5px;
      z-index: 2;
    }

    .card-info {
      padding: 20px;
      display: flex;
      flex-direction: column;
      flex-grow: 1;
      background: var(--bg-card);
    }

    .card-heading {
      font-size: 16px;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 6px;
      line-height: 1.35;
    }

    .card-text {
      font-size: 13px;
      color: var(--text-muted);
      line-height: 1.5;
    }

    /* Specifications Section */
    .specs-section {
      background: var(--bg-card);
      border: 1px solid var(--border-subtle);
      border-radius: 24px;
      padding: 40px;
      margin-bottom: 60px;
      box-shadow: var(--shadow-sm);
    }

    .specs-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
      margin-top: 24px;
    }

    .spec-item {
      padding: 20px;
      background: #f8faff;
      border-radius: 16px;
      border: 1px solid rgba(15, 23, 42, 0.05);
    }

    .spec-label {
      font-size: 11.5px;
      font-weight: 700;
      text-transform: uppercase;
      letter-spacing: 1px;
      color: var(--accent-primary);
      display: block;
      margin-bottom: 6px;
    }

    .spec-value {
      font-size: 16px;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 4px;
    }

    .spec-detail {
      font-size: 12.5px;
      color: var(--text-sub);
      line-height: 1.45;
    }

    /* FAQ Section */
    .faq-section {
      background: var(--bg-card);
      border: 1px solid var(--border-subtle);
      border-radius: 24px;
      padding: 40px;
      box-shadow: var(--shadow-sm);
    }

    .faq-list {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 20px;
      margin-top: 28px;
    }

    .faq-item {
      padding: 22px;
      background: #f8faff;
      border-radius: 16px;
      border: 1px solid rgba(15, 23, 42, 0.05);
      transition: var(--transition);
    }

    .faq-item:hover {
      border-color: rgba(99, 102, 241, 0.25);
      background: #ffffff;
      box-shadow: var(--shadow-sm);
    }

    .faq-question {
      font-size: 15px;
      font-weight: 700;
      color: var(--text-main);
      margin-bottom: 8px;
      line-height: 1.4;
    }

    .faq-answer {
      font-size: 13px;
      color: var(--text-muted);
      line-height: 1.55;
    }

    /* Responsive Breakpoints */
    @media (max-width: 1024px) {
      .grid-4-col {
        grid-template-columns: repeat(2, 1fr);
        gap: 18px;
      }
      .highlights-row {
        grid-template-columns: repeat(2, 1fr);
      }
      .specs-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .faq-list {
        grid-template-columns: 1fr;
      }
    }

    @media (max-width: 640px) {
      body {
        padding: 24px 12px 60px;
      }
      .grid-4-col {
        grid-template-columns: repeat(2, 1fr);
        gap: 12px;
      }
      .card-info {
        padding: 14px 12px;
      }
      .card-heading {
        font-size: 14px;
      }
      .card-text {
        font-size: 12px;
      }
      .highlights-row {
        grid-template-columns: repeat(2, 1fr);
        gap: 10px;
      }
      .specs-section, .faq-section {
        padding: 24px 16px;
      }
      .specs-grid {
        grid-template-columns: 1fr;
      }
    }