:root {
      --navy: #1e3a5f;
      --yellow: #f7ce46;
      --white: #ffffff;
      --light-bg: #f8fafc;
      --card-bg: #ffffff;
      --text-dark: #1e293b;
      --text-muted: #64748b;
      --shadow: 0 4px 15px rgba(30, 58, 95, 0.08);
      --shadow-lg: 0 8px 25px rgba(30, 58, 95, 0.12);
    }
    
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }
    
    body {
      font-family: 'Poppins', sans-serif;
      background: linear-gradient(135deg, #f0f4f8 0%, #e2e8f0 100%);
      color: var(--text-dark);
      line-height: 1.6;
      overflow-x: hidden;
    }
     /* WhatsApp Button */
    .whatsapp-unlock-btn {
      display: flex;
      align-items: center;
      justify-content: center;
      gap: 12px;
      width: 80%;
      padding: 18px;
      background: linear-gradient(135deg, #25D366 0%, #128C7E 100%);
      color: white;
      text-decoration: none;
      border-radius: 16px;
      font-weight: 800;
      font-size: 17px;
      transition: all 0.4s cubic-bezier(0.23, 1, 0.32, 1);
      box-shadow: 0 10px 30px rgba(37, 211, 102, 0.4);
      position: relative;
      overflow: hidden;
    }

    .whatsapp-unlock-btn::before {
      content: '';
      position: absolute;
      top: 50%;
      left: 50%;
      width: 0;
      height: 0;
      background: rgba(255, 255, 255, 0.2);
      border-radius: 50%;
      transform: translate(-50%, -50%);
      transition: width 0.6s, height 0.6s;
    }

    .whatsapp-unlock-btn:hover::before {
      width: 400px;
      height: 400px;
    }

    .whatsapp-unlock-btn:hover {
      transform: translateY(-3px) scale(1.02);
      box-shadow: 0 15px 40px rgba(37, 211, 102, 0.6);
    }

    .whatsapp-unlock-btn:active {
      transform: translateY(-1px) scale(0.98);
    }

    .whatsapp-icon {
      font-size: 24px;
      animation: whatsappBounce 2s infinite;
    }

    @keyframes whatsappBounce {
      0%, 100% {
        transform: scale(1);
      }
      50% {
        transform: scale(1.2);
      }
    }

    /* Lock Icon Animation */
    .lock-icon {
      display: inline-block;
      animation: lockShake 1s infinite;
    }

    @keyframes lockShake {
      0%, 100% { transform: rotate(0deg); }
      25% { transform: rotate(-10deg); }
      75% { transform: rotate(10deg); }
    }

    /* Glowing effect on hover */
    .premium-book-card:hover .book-cover-premium {
      box-shadow: inset 0 0 50px rgba(247, 206, 70, 0.3);
    }

    /* Ribbon */
    .premium-ribbon {
      position: absolute;
      top: 30px;
      right: -35px;
      background: linear-gradient(135deg, #dc2626, #991b1b);
      color: white;
      padding: 8px 40px;
      transform: rotate(45deg);
      font-size: 12px;
      font-weight: 700;
      box-shadow: 0 4px 15px rgba(220, 38, 38, 0.4);
      z-index: 4;
      letter-spacing: 1px;
    }   
    main {
      max-width: 1200px;
      margin: 0 auto;
      padding: 40px 20px;
      animation: fadeInUp 0.6s ease-out;
    }
    
    @keyframes fadeInUp {
      from {
        opacity: 0;
        transform: translateY(30px);
      }
      to {
        opacity: 1;
        transform: translateY(0);
      }
    }
    
    .page-head {
      text-align: center;
/*      margin-bottom: 40px;*/
    }
    
    .page-title {
      font-size: 48px;
      font-weight: 800;
      color: var(--navy);
      margin-bottom: 12px;
      animation: fadeInUp 0.7s ease-out;
    }
    
    .page-sub {
      font-size: 18px;
      color: var(--text-muted);
      max-width: 700px;
      margin: 0 auto;
      animation: fadeInUp 0.8s ease-out;
    }

    .category-section {
      margin-bottom: 30px;
    }
    
    .category-header {
      display: flex;
      align-items: center;
      gap: 15px;
      margin-bottom: 30px;
      padding-bottom: 10px;
      padding-top: 10px;
      border-bottom: 2px solid var(--yellow);
      border-top: 2px solid var(--yellow);
    }
    
    .category-icon {
      width: 50px;
      height: 50px;
      background: linear-gradient(135deg, var(--navy), #2d5990);
      border-radius: 15px;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 28px;
      box-shadow: var(--shadow);
    }
    
    .category-title {
      font-size: 26px;
      font-weight: 800;
      color: var(--navy);
    }
    
    .books-grid {
      display: flex;
      flex-wrap: wrap;
/*      display: grid;*/
/*      grid-template-columns: repeat(auto-fill, minmax(375px, 1fr));*/
      gap: 30px;
    }
    
    .book-card {
      background: white;
      border-radius: 20px;
      overflow: hidden;
      box-shadow: var(--shadow);
      transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
      position: relative;
      display: flex;
      flex-wrap: wrap;
      flex-direction: column;
      animation: zoomIn 0.6s ease-out backwards;
      border: 2px solid black;
      flex-basis: 300px;
    }
    
    @keyframes zoomIn {
      from {
        opacity: 0;
        transform: scale(0.9);
      }
      to {
        opacity: 1;
        transform: scale(1);
      }
    }
    
    .book-card:nth-child(1) { animation-delay: 0.1s; }
    .book-card:nth-child(2) { animation-delay: 0.15s; }
    .book-card:nth-child(3) { animation-delay: 0.2s; }
    .book-card:nth-child(4) { animation-delay: 0.25s; }
    .book-card:nth-child(5) { animation-delay: 0.3s; }
    .book-card:nth-child(6) { animation-delay: 0.35s; }
    
    .book-card:hover {
      transform: translateY(-12px) rotate(-1deg);
      box-shadow: 0 20px 40px rgba(30, 58, 95, 0.2);
    }
    
    .book-cover {
      width: 100%;
      position: relative;
/*      height: 100%;*/
      background: linear-gradient(135deg, var(--navy), #2d5990);
      display: flex;
      align-items: center;
      justify-content: center;
      overflow: hidden;
    }
    
    .book-cover::before {
      content: '';
      position: absolute;
      top: 0;
      left: 0;
      right: 0;
      bottom: 0;
      background: url('data:image/svg+xml,<svg width="100" height="100" xmlns="http://www.w3.org/2000/svg"><circle cx="50" cy="50" r="2" fill="rgba(247,206,70,0.1)"/></svg>');
      opacity: 0.5;
    }
    
    .book-cover img {
      width: 60%;
      object-fit: cover;
      transition: transform 0.3s ease;
    }
    
    .book-card:hover .book-cover img {
/*      transform: scale(1.1);*/
    }
    
    .book-icon {
      font-size: 80px;
      color: var(--yellow);
      position: relative;
      z-index: 1;
    }
    
    .premium-badge {
      position: absolute;
      top: 15px;
      right: 15px;
      background: var(--yellow);
      color: var(--navy);
      padding: 6px 14px;
      border-radius: 20px;
      font-size: 12px;
      font-weight: 700;
      box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
      z-index: 2;
    }
    
    .book-info {
      padding: 15px;
    }
    
    .book-title {
      font-size: 20px;
      font-weight: 700;
      color: var(--navy);
      margin-bottom: 8px;
      line-height: 1.4;
    }
    
    .book-author {
      font-size: 14px;
      color: var(--text-muted);
      margin-bottom: 12px;
      font-weight: 500;
    }
    
    .book-meta {
      display: flex;
      gap: 15px;
      margin-bottom: 15px;
      flex-wrap: wrap;
    }
    
    .meta-item {
      display: flex;
      align-items: center;
      gap: 6px;
      font-size: 13px;
      color: var(--text-muted);
      font-weight: 600;
    }
    .btns{
      display: flex;
      width: 100%;
/*      flex-direction: column;*/
      gap: 5px;      
      margin-bottom: 7.5px;
    }
    
    .download-btn {
      width: 48%;
      background: linear-gradient(135deg, var(--navy), #2d5990);
      color: white;
      padding: 10px;
      border-radius: 15px;
      text-align: center;
      text-decoration: none;
      font-weight: 700;
      font-size: 12px;
      display: flex;
      align-items: center;
      justify-content: center;
      transition: all 0.3s ease;
      box-shadow: 0 4px 15px rgba(30, 58, 95, 0.3);
      margin: auto;
      margin-bottom: -8px;
    }
    
    .download-btn:hover {
      background: linear-gradient(135deg, #2d5990, var(--navy));
      transform: translateY(-2px);
      box-shadow: 0 6px 20px rgba(30, 58, 95, 0.4);
    }
    
    .stats-banner {
      background: linear-gradient(135deg, var(--navy) 0%, #2d5990 100%);
      padding: 50px 30px;
      border-radius: 20px;
      margin-bottom: 60px;
      text-align: center;
    }
    
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
      gap: 30px;
      max-width: 900px;
      margin: 0 auto;
    }
    
    .stat-item {
      color: white;
    }
    
    .stat-number {
      font-size: 42px;
      font-weight: 800;
      color: var(--yellow);
      display: block;
      margin-bottom: 8px;
    }
    
    .stat-label {
      font-size: 15px;
      font-weight: 600;
      opacity: 0.95;
    }
    
    
    /* Responsive */
    @media (max-width: 480px) {
      .book-title-premium {
        font-size: 20px;
      }

      .book-icon-premium {
        font-size: 90px;
      }

      .price-badge {
        font-size: 16px;
        padding: 10px 20px;
      }
      .category-icon{
        width: 40px;
        height: 40px;
      }
      .category-title{
        font-size: 18px;
      }
    }

    @media (max-width: 768px) {
      .logo-text h1 {
        font-size: 16px;
      }
      
      .logo-text p {
        font-size: 11px;
      }
      
      .page-title {
        font-size: 32px;
      }
      
      .page-sub {
        font-size: 16px;
      }
      .search-box {
        width: 100%;
      }
      
      .filter-chips {
        width: 100%;
        justify-content: center;
      }
      
      .books-grid {
        grid-template-columns: 1fr;
      }
      
      .category-title {
        font-size: 24px;
      }
    }