/* ===================================================
   ACADEMY & BOOK PUBLISHING DESIGN SYSTEM (2026 EDITION)
   Phong cách chuẩn Nhà Xuất Bản & Nền tảng Giáo dục Hiện đại
   (Tương tự Vietcetera Academy, Mindvalley, Alpha Books, Nha Nam)
   =================================================== */

:root {
  --bg-warm: #F8F9FA;
  --surface: #FFFFFF;
  --text-main: #191F28;
  --text-muted: #6B7684;
  --brand-navy: #0F1D36;
  --brand-blue: #1D58D8;
  --brand-blue-hover: #1545B0;
  --accent-amber: #D97706;
  --accent-warm-bg: #FFFBEB;
  --border-light: #E5E8EB;
  --radius-card: 16px;
  --radius-btn: 12px;
}

body {
  background-color: var(--bg-warm);
  color: var(--text-main);
  font-family: 'Be Vietnam Pro', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  letter-spacing: -0.015em;
  -webkit-tap-highlight-color: transparent;
}

.font-editorial {
  font-family: 'Be Vietnam Pro', sans-serif;
  font-weight: 800;
  letter-spacing: -0.025em;
}

/* Realistic 3D Book Presentation */
.book-spine-wrapper {
  perspective: 1000px;
}

.real-book-cover {
  position: relative;
  background-size: cover;
  border-radius: 4px 10px 10px 4px;
  box-shadow: 
    -4px 0 0 -1px #d1d5db,
    -8px 0 0 -2px #e5e7eb,
    0 12px 28px -4px rgba(15, 29, 54, 0.2),
    0 4px 10px -2px rgba(15, 29, 54, 0.08);
  transition: transform 0.3s cubic-bezier(0.34, 1.56, 0.64, 1), box-shadow 0.3s ease;
  overflow: hidden;
}

.real-book-cover::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  bottom: 0;
  width: 14px;
  background: linear-gradient(to right, rgba(0,0,0,0.25) 0%, rgba(255,255,255,0.15) 35%, rgba(0,0,0,0.15) 100%);
  z-index: 10;
  border-right: 1px solid rgba(0,0,0,0.1);
}

.real-book-cover::after {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(255,255,255,0.12) 0%, rgba(0,0,0,0.1) 100%);
  pointer-events: none;
}

.book-card-container:hover .real-book-cover {
  transform: translateY(-6px) rotate(-1deg);
  box-shadow: 
    -4px 0 0 -1px #d1d5db,
    -8px 0 0 -2px #e5e7eb,
    0 20px 35px -5px rgba(15, 29, 54, 0.28),
    0 8px 16px -4px rgba(15, 29, 54, 0.12);
}

/* Tab active styles */
.tab-active {
  color: var(--brand-blue);
  border-bottom: 2px solid var(--brand-blue);
  font-weight: 700;
}

/* Clean Custom Scrollbar */
::-webkit-scrollbar {
  width: 6px;
  height: 6px;
}
::-webkit-scrollbar-track {
  background: #f1f5f9;
}
::-webkit-scrollbar-thumb {
  background: #cbd5e1;
  border-radius: 9999px;
}
::-webkit-scrollbar-thumb:hover {
  background: #94a3b8;
}

/* Modals Slide Animation */
@keyframes modalSlideUp {
  from {
    transform: translateY(100%);
    opacity: 0;
  }
  to {
    transform: translateY(0);
    opacity: 1;
  }
}

.animate-slide-up {
  animation: modalSlideUp 0.28s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}

@keyframes fadeIn {
  from { opacity: 0; transform: scale(0.98); }
  to { opacity: 1; transform: scale(1); }
}

.animate-fade-in {
  animation: fadeIn 0.2s ease-out forwards;
}

/* Custom Checkbox Pill */
.checkbox-pill input:checked + div {
  border-color: #1D58D8;
  background-color: #EFF6FF;
}

/* Subtle Shimmer for High Value Deal */
@keyframes subtleShimmer {
  0% { background-position: -200% 0; }
  100% { background-position: 200% 0; }
}
.shimmer-badge {
  background: linear-gradient(90deg, #F59E0B 0%, #FDE68A 50%, #F59E0B 100%);
  background-size: 200% 100%;
  animation: subtleShimmer 4s infinite linear;
}