/* ============================================
   KERYGMA Library Design System
   ============================================ */

/* CSS Variables (Design Tokens) */
:root {
  /* Colors */
  --color-bg: #020617;
  --color-surface: rgba(15, 23, 42, 0.6);
  --color-surface-solid: #0f172a;
  --color-border: rgba(255, 255, 255, 0.05);
  --color-border-hover: rgba(255, 255, 255, 0.1);
  
  --color-primary: #38bdf8;    /* sky-400 */
  --color-primary-dim: rgba(56, 189, 248, 0.3);
  --color-accent: #a78bfa;     /* purple-400 */
  --color-accent-dim: rgba(167, 139, 250, 0.3);
  
  --color-text: #f8fafc;
  --color-text-muted: #94a3b8;
  --color-text-dim: #64748b;
  
  --color-success: #4ade80;
  --color-success-bg: rgba(74, 222, 128, 0.1);
  --color-warning: #fb923c;
  --color-warning-bg: rgba(251, 146, 60, 0.1);
  --color-danger: #f87171;
  --color-danger-bg: rgba(248, 113, 113, 0.1);
  
  /* Typography */
  --font-main: 'Outfit', 'Noto Sans KR', sans-serif;
  --font-serif: 'Noto Serif KR', serif;
  
  /* Spacing */
  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  --space-2xl: 3rem;
  --space-3xl: 4rem;
  
  /* Border Radius */
  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --radius-full: 9999px;
  
  /* Shadows */
  --shadow-glow: 0 0 15px rgba(56, 189, 248, 0.3);
  --shadow-card: 0 4px 6px -1px rgba(0, 0, 0, 0.3);
  --shadow-card-hover: 0 10px 20px -5px rgba(0, 0, 0, 0.5);
  
  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-normal: 300ms ease;
  --transition-smooth: 400ms cubic-bezier(0.23, 1, 0.32, 1);
}

/* ============================================
   Base Styles
   ============================================ */

body {
  font-family: var(--font-main);
  background-color: var(--color-bg);
  color: var(--color-text);
  line-height: 1.6;
}

/* Font Utility */
.font-serif {
  font-family: var(--font-serif);
}

/* ============================================
   Glass Panel Component
   ============================================ */

.glass-panel {
  background: var(--color-surface);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--color-border);
}

/* ============================================
   Neon Text Effect
   ============================================ */

.neon-text {
  text-shadow: 0 0 10px var(--color-primary-dim);
}

.neon-text-purple {
  text-shadow: 0 0 10px var(--color-accent-dim);
}

/* ============================================
   Book Card Component
   ============================================ */

.book-card {
  transition: all var(--transition-smooth);
  transform-style: preserve-3d;
}

.book-card:hover {
  transform: translateY(-8px);
  box-shadow: var(--shadow-card-hover);
}

.book-card:hover .book-cover {
  transform: scale(1.05);
}

.book-cover {
  transition: transform 500ms ease;
}

/* ============================================
   Status Badges
   ============================================ */

.status-badge {
  padding: 0.25rem 0.5rem;
  font-size: 0.625rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  border-radius: var(--radius-sm);
  backdrop-filter: blur(8px);
}

.status-available {
  background: var(--color-success-bg);
  color: var(--color-success);
  border: 1px solid rgba(74, 222, 128, 0.3);
}

.status-reprint {
  background: var(--color-warning-bg);
  color: var(--color-warning);
  border: 1px solid rgba(251, 146, 60, 0.3);
}

.status-archived {
  background: var(--color-danger-bg);
  color: var(--color-danger);
  border: 1px solid rgba(248, 113, 113, 0.3);
}

/* ============================================
   Filter Buttons
   ============================================ */

.filter-btn {
  padding: 0.5rem 1rem;
  border-radius: var(--radius-full);
  font-size: 0.875rem;
  font-weight: 500;
  transition: all var(--transition-normal);
  cursor: pointer;
}

.filter-btn:not(.active) {
  background: rgba(30, 41, 59, 0.5);
  border: 1px solid var(--color-border-hover);
  color: var(--color-text-muted);
}

.filter-btn:not(.active):hover {
  border-color: var(--color-primary-dim);
  color: var(--color-primary);
}

.filter-btn.active {
  background: rgba(56, 189, 248, 0.1);
  border: 1px solid var(--color-primary-dim);
  color: var(--color-primary);
  box-shadow: var(--shadow-glow);
}

/* ============================================
   Tag Pills
   ============================================ */

.tag-pill {
  display: inline-block;
  padding: 0.25rem 0.5rem;
  font-size: 0.625rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  border-radius: var(--radius-sm);
  background: var(--color-surface-solid);
  border: 1px solid var(--color-border);
  color: var(--color-text-muted);
  transition: color var(--transition-normal);
}

.book-card:hover .tag-pill {
  color: var(--color-primary);
}

/* ============================================
   Quote Card Component
   ============================================ */

.quote-card {
  font-family: var(--font-serif);
  position: relative;
  background: linear-gradient(135deg, rgba(30, 41, 59, 0.5), rgba(15, 23, 42, 0.5));
  border-left: 4px solid var(--color-primary);
  padding: var(--space-lg);
  border-radius: var(--radius-lg);
  transition: transform var(--transition-normal);
}

.quote-card:hover {
  transform: translateX(4px);
}

/* ============================================
   Prose (Rich Text)
   ============================================ */

.prose p {
  margin-bottom: 1.2rem;
  line-height: 1.8;
  font-size: 1.05rem;
  color: var(--color-text-muted);
  font-family: var(--font-serif);
}

.prose strong {
  color: var(--color-text);
  font-weight: 700;
}

.prose a {
  color: var(--color-primary);
  text-decoration: underline;
  text-underline-offset: 4px;
}

/* ============================================
   Custom Scrollbar
   ============================================ */

::-webkit-scrollbar {
  width: 6px;
}

::-webkit-scrollbar-track {
  background: var(--color-surface-solid);
}

::-webkit-scrollbar-thumb {
  background: var(--color-text-dim);
  border-radius: 3px;
}

::-webkit-scrollbar-thumb:hover {
  background: var(--color-text-muted);
}

/* ============================================
   Noise Texture Overlay
   ============================================ */

.noise-overlay::before {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  content: "";
  opacity: 0.05;
  z-index: 50;
  pointer-events: none;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noiseFilter'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.65' numOctaves='3' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noiseFilter)'/%3E%3C/svg%3E");
}

/* ============================================
   Card Fade-In Animation
   ============================================ */

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.animate-fade-in {
  animation: fadeInUp 0.5s ease forwards;
}

/* Staggered animation delay using CSS custom property */
.book-card {
  opacity: 0;
  animation: fadeInUp 0.5s ease forwards;
  animation-delay: calc(var(--card-index, 0) * 50ms);
}

/* ============================================
   Utility Classes
   ============================================ */

.text-gradient {
  background: linear-gradient(to right, var(--color-primary), var(--color-accent));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.line-clamp-1 {
  display: -webkit-box;
  -webkit-line-clamp: 1;
  line-clamp: 1;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.line-clamp-2 {
  display: -webkit-box;
  -webkit-line-clamp: 2;
  line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.line-clamp-3 {
  display: -webkit-box;
  -webkit-line-clamp: 3;
  line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}