/* ============================================================
   BIBLIOTECA DIGITAL — DESIGN SYSTEM (visitante)
   Tokens de diseño + componentes + microinteracciones
   ============================================================ */

:root {
  /* ---- Colores de marca ---- */
  --color-primary: #667eea;
  --color-primary-dark: #5a67d8;
  --color-secondary: #764ba2;
  --color-secondary-dark: #6b3f9e;

  /* ---- Texto (contraste AA sobre blanco) ---- */
  --color-text: #2d3748;
  --color-text-soft: #4a5568;
  --color-text-muted: #6b7280;
  --color-text-faint: #8896a8;
  --color-on-dark: #ffffff;

  /* ---- Superficies y bordes ---- */
  --surface-glass: rgba(255, 255, 255, 0.95);
  --surface-glass-dark: rgba(0, 0, 0, 0.85);
  --surface-dark: #1a1a1a;
  --border-color: #e0e0e0;
  --border-light: #eeeeee;

  /* ---- Gradientes de marca ---- */
  --gradient-brand: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  --gradient-brand-soft: linear-gradient(
    135deg,
    rgba(102, 126, 234, 0.9),
    rgba(118, 75, 162, 0.9)
  );

  /* ---- Tipografía ---- */
  --font-family: "Roboto", sans-serif;
  --font-size-xs: 0.75rem;
  --font-size-sm: 0.8rem;
  --font-size-md: 0.9rem;
  --font-size-base: 1rem;
  --font-size-lg: 1.2rem;
  --font-size-xl: 1.3rem;
  --font-size-hero: 3.5rem;

  /* ---- Radios ---- */
  --radius-sm: 10px;
  --radius-md: 12px;
  --radius-lg: 20px;
  --radius-pill: 30px;

  /* ---- Sombras ---- */
  --shadow-sm: 0 2px 10px rgba(0, 0, 0, 0.1);
  --shadow-md: 0 5px 20px rgba(0, 0, 0, 0.15);
  --shadow-lg: 0 10px 30px rgba(0, 0, 0, 0.2);
  --shadow-xl: 0 20px 40px rgba(0, 0, 0, 0.3);

  /* ---- Transiciones / microinteracciones ---- */
  --transition-fast: 0.2s ease;
  --transition-base: 0.3s ease;
  --transition-smooth: 0.4s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-bounce: 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);

  /* ---- Espaciado ---- */
  --space-xs: 4px;
  --space-sm: 8px;
  --space-md: 15px;
  --space-lg: 20px;
  --space-xl: 25px;
}

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

/* ========== BASE ========== */
html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-family);
  overflow-x: hidden;
  position: relative;
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

::selection {
  background: var(--color-primary);
  color: var(--color-on-dark);
}

/* Foco visible accesible (teclado) */
:focus-visible {
  outline: 3px solid var(--color-primary);
  outline-offset: 2px;
  border-radius: var(--radius-sm);
}

/* ========== FONDO ANIMADO CON BURBUJAS ========== */
.animated-bg {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: -2;
  overflow: hidden;
  background: var(--gradient-brand);
}

/* ---- Aurora: degradado animado por TRANSFORM en capa sobredimensionada ----
   Corre en el compositor de la GPU (no repinta píxeles), por lo que es fluida
   incluso con las burbujas encima y apenas consume CPU del visitante.       */
.animated-bg::before {
  content: "";
  position: absolute;
  inset: -60%;
  background: var(--gradient-brand);
  pointer-events: none;
  will-change: transform;
  transform: translate3d(0, 0, 0);
}

body.gradiente-animado .animated-bg::before {
  animation: auroraDrift var(--grad-dur, 16s) ease-in-out infinite alternate;
}

@keyframes auroraDrift {
  0% {
    transform: translate3d(-5%, -4%, 0) scale(1);
  }
  50% {
    transform: translate3d(0, 0, 0) scale(1.06);
  }
  100% {
    transform: translate3d(5%, 4%, 0) scale(1);
  }
}

.bubble {
  position: absolute;
  background: rgba(255, 255, 255, 0.15);
  border-radius: 50%;
  backdrop-filter: blur(3px);
  animation: floatBubble 12s infinite ease-in-out;
  pointer-events: none;
  box-shadow: 0 0 20px rgba(255, 255, 255, 0.1);
}

@keyframes floatBubble {
  0% {
    transform: translateY(100vh) scale(0);
    opacity: 0;
  }
  10% {
    opacity: 0.6;
  }
  50% {
    opacity: 0.4;
    transform: translateY(50vh) scale(1);
  }
  90% {
    opacity: 0.6;
  }
  100% {
    transform: translateY(-20vh) scale(0.8);
    opacity: 0;
  }
}

.bubble-small {
  position: absolute;
  background: rgba(255, 255, 255, 0.2);
  border-radius: 50%;
  backdrop-filter: blur(2px);
  animation: floatSmall 8s infinite ease-in-out;
  pointer-events: none;
}

@keyframes floatSmall {
  0% {
    transform: translateY(100vh) scale(0);
    opacity: 0;
  }
  20% {
    opacity: 0.5;
  }
  80% {
    opacity: 0.5;
  }
  100% {
    transform: translateY(-20vh) scale(1.2);
    opacity: 0;
  }
}

.particle {
  position: absolute;
  background: rgba(255, 255, 255, 0.4);
  border-radius: 50%;
  pointer-events: none;
  animation: particleFloat 15s infinite linear;
}

@keyframes particleFloat {
  0% {
    transform: translateY(100vh) rotate(0deg);
    opacity: 0;
  }
  10% {
    opacity: 0.8;
  }
  90% {
    opacity: 0.8;
  }
  100% {
    transform: translateY(-20vh) rotate(360deg);
    opacity: 0;
  }
}

.wave {
  position: absolute;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 100px;
  background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 1440 320"><path fill="rgba(255,255,255,0.1)" fill-opacity="1" d="M0,192L48,197.3C96,203,192,213,288,208C384,203,480,181,576,181.3C672,181,768,203,864,213.3C960,224,1056,224,1152,213.3C1248,203,1344,181,1392,170.7L1440,160L1440,320L1392,320C1344,320,1248,320,1152,320C1056,320,960,320,864,320C768,320,672,320,576,320C480,320,384,320,288,320C192,320,96,320,48,320L0,320Z"></path></svg>')
    repeat-x;
  background-size: cover;
  animation: waveMove 10s linear infinite;
  pointer-events: none;
  z-index: -1;
}

@keyframes waveMove {
  0% {
    background-position-x: 0;
  }
  100% {
    background-position-x: 1440px;
  }
}

/* ========== NAVBAR ========== */
.navbar-custom {
  background: rgba(0, 0, 0, 0.3);
  backdrop-filter: blur(10px);
  box-shadow: var(--shadow-sm);
  transition: all var(--transition-base);
}

.navbar-custom:hover {
  background: rgba(0, 0, 0, 0.4);
}

/* ========== LOGOS Y SELECTOR DE IDIOMA ========== */
.brand-logo {
  height: 40px;
  width: auto;
  max-width: 190px;
  object-fit: contain;
  border-radius: var(--radius-sm);
  background: rgba(255, 255, 255, 0.92);
  padding: 3px 6px;
  box-shadow: var(--shadow-sm);
  transition:
    transform var(--transition-base),
    box-shadow var(--transition-base);
}

.navbar-brand:hover .brand-logo {
  transform: scale(1.04);
  box-shadow: var(--shadow-md);
}

.hero-logo {
  display: block;
  margin: 0 auto 18px;
  max-width: min(460px, 88%);
  height: auto;
  border-radius: var(--radius-md);
  background: rgba(255, 255, 255, 0.95);
  padding: 14px 22px;
  box-shadow: var(--shadow-lg);
  animation: fadeInDown 0.8s ease;
}

.lang-switch {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  background: rgba(255, 255, 255, 0.15);
  border: 1px solid rgba(255, 255, 255, 0.35);
  backdrop-filter: blur(8px);
  border-radius: var(--radius-pill);
  padding: 3px;
}

.lang-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 40px;
  padding: 6px 12px;
  border-radius: var(--radius-pill);
  color: var(--color-on-dark);
  font-size: var(--font-size-sm);
  font-weight: 700;
  letter-spacing: 0.5px;
  text-decoration: none;
  transition: all var(--transition-fast);
}

.lang-btn:hover,
.lang-btn:focus-visible {
  color: var(--color-on-dark);
  background: rgba(255, 255, 255, 0.25);
}

.lang-btn.is-active {
  background: #ffffff;
  color: var(--color-primary-dark);
  box-shadow: var(--shadow-sm);
}

@media (max-width: 768px) {
  .brand-logo {
    height: 34px;
    max-width: 150px;
  }
  .hero-logo {
    max-width: 92%;
    padding: 10px 16px;
  }
  .lang-btn {
    min-width: 34px;
    padding: 5px 9px;
  }
}

/* ========== HERO ========== */
.hero-section {
  position: relative;
  padding: 80px 0;
  text-align: center;
  color: var(--color-on-dark);
  background: rgba(0, 0, 0, 0.2);
  backdrop-filter: blur(5px);
}

.hero-title {
  font-size: var(--font-size-hero);
  font-weight: 800;
  margin-bottom: 20px;
  text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.3);
  animation: fadeInDown 0.8s ease;
}

.hero-subtitle {
  font-size: var(--font-size-xl);
  opacity: 0.95;
  animation: fadeInUp 0.8s ease;
}

@keyframes fadeInDown {
  from {
    opacity: 0;
    transform: translateY(-30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* ========== TARJETAS DE LIBROS ========== */
.books-grid {
  padding: 40px 0;
  position: relative;
  z-index: 1;
}

.book-card {
  background: var(--surface-glass);
  backdrop-filter: blur(10px);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-lg);
  transition: all var(--transition-bounce);
  cursor: pointer;
  height: 100%;
  position: relative;
}

.book-card:hover {
  transform: translateY(-10px) scale(1.02);
  box-shadow: var(--shadow-xl);
  background: #ffffff;
}

/* Feedback de presión al hacer clic */
.book-card:active {
  transform: translateY(-2px) scale(0.98);
  transition-duration: var(--transition-fast);
}

.book-cover {
  background: var(--gradient-brand-soft);
  padding: 40px 20px;
  text-align: center;
  position: relative;
  transition: all var(--transition-base);
}

.book-card:hover .book-cover {
  background: var(--gradient-brand);
}

.book-cover i {
  font-size: 80px;
  color: var(--color-on-dark);
  text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.3);
  transition: transform var(--transition-base);
}

.book-card:hover .book-cover i {
  transform: scale(1.1);
}

.book-badge {
  position: absolute;
  top: 15px;
  right: 15px;
  background: rgba(0, 0, 0, 0.7);
  color: var(--color-on-dark);
  padding: 5px 12px;
  border-radius: var(--radius-lg);
  font-size: 11px;
  font-weight: 500;
  backdrop-filter: blur(5px);
}

.book-info {
  padding: var(--space-lg);
}

.book-title {
  font-size: var(--font-size-lg);
  font-weight: 700;
  margin-bottom: 10px;
  color: var(--color-text);
  display: -webkit-box;
  -webkit-line-clamp: 2;
  line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.book-author {
  color: var(--color-text-soft);
  font-size: var(--font-size-md);
  margin-bottom: 10px;
}

.book-author i {
  margin-right: 5px;
  font-size: var(--font-size-xs);
}

.book-description {
  color: var(--color-text-muted);
  font-size: var(--font-size-sm);
  margin-bottom: 15px;
  line-height: 1.4;
  display: -webkit-box;
  -webkit-line-clamp: 3;
  line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.book-meta {
  display: flex;
  justify-content: space-between;
  font-size: var(--font-size-xs);
  color: var(--color-text-faint);
  margin-top: 15px;
  padding-top: 10px;
  border-top: 1px solid var(--border-light);
}

/* ========== FILTROS ========== */
.filters-section {
  background: var(--surface-glass);
  backdrop-filter: blur(10px);
  padding: var(--space-lg);
  border-radius: var(--radius-lg);
  margin-bottom: 30px;
  box-shadow: var(--shadow-sm);
  transition: all var(--transition-base);
}

.filters-section:hover {
  box-shadow: var(--shadow-md);
}

.search-box {
  position: relative;
}

.search-box i {
  position: absolute;
  left: 15px;
  top: 50%;
  transform: translateY(-50%);
  color: var(--color-text-faint);
}

.search-box input {
  padding-left: 40px;
  border-radius: var(--radius-md);
  border: 2px solid var(--border-color);
  transition: all var(--transition-base);
}

.search-box input:focus {
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

.form-select {
  border-radius: var(--radius-md);
  border: 2px solid var(--border-color);
  transition: all var(--transition-base);
}

.form-select:focus {
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

/* ========== VISOR DE PDF MEJORADO ========== */
.pdf-viewer-modal {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.95);
  z-index: 9999;
  display: none;
  flex-direction: column;
  animation: fadeInModal var(--transition-smooth);
}

@keyframes fadeInModal {
  from {
    opacity: 0;
    transform: scale(0.96);
  }
  to {
    opacity: 1;
    transform: scale(1);
  }
}

.pdf-toolbar {
  background: rgba(0, 0, 0, 0.9);
  backdrop-filter: blur(10px);
  color: var(--color-on-dark);
  padding: 12px 25px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 10px;
}

.pdf-title {
  font-size: 1.1rem;
  font-weight: 500;
  flex: 1;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.pdf-controls {
  display: flex;
  gap: 10px;
  align-items: center;
  flex-wrap: wrap;
}

.pdf-controls button {
  background: rgba(255, 255, 255, 0.15);
  border: none;
  color: var(--color-on-dark);
  padding: 8px 16px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: all var(--transition-smooth);
  font-size: 14px;
}

.pdf-controls button:hover {
  background: rgba(255, 255, 255, 0.3);
  transform: translateY(-2px);
}

.pdf-controls button:active {
  transform: translateY(0) scale(0.95);
}

.pdf-controls input {
  width: 70px;
  padding: 8px;
  border-radius: var(--radius-sm);
  border: none;
  text-align: center;
  font-weight: 500;
}

.pdf-container {
  flex: 1;
  position: relative;
  background: var(--surface-dark);
  overflow: auto;
  display: flex;
  justify-content: center;
  align-items: center;
}

/* Transiciones suaves para el canvas */
#pdfCanvas {
  display: block;
  margin: 20px auto;
  box-shadow: 0 0 30px rgba(0, 0, 0, 0.5);
  border-radius: 8px;
  transition: opacity var(--transition-smooth);
  will-change: transform;
}

/* Animación de cambio de página mejorada */
.page-transition {
  animation: pageSmoothFlip 0.5s var(--transition-smooth);
}

@keyframes pageSmoothFlip {
  0% {
    opacity: 0.3;
    transform: perspective(1000px) rotateY(15deg) scale(0.96);
  }
  50% {
    opacity: 0.7;
    transform: perspective(1000px) rotateY(5deg) scale(0.98);
  }
  100% {
    opacity: 1;
    transform: perspective(1000px) rotateY(0deg) scale(1);
  }
}

/* Animación de zoom suave */
.zoom-transition {
  animation: zoomSmooth 0.25s var(--transition-smooth);
}

@keyframes zoomSmooth {
  0% {
    opacity: 0.6;
    transform: scale(0.98);
  }
  100% {
    opacity: 1;
    transform: scale(1);
  }
}

.pdf-loading {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  color: var(--color-on-dark);
  text-align: center;
}

.pdf-loading i {
  animation: spinSmooth 1s var(--transition-smooth) infinite;
  font-size: 50px;
  margin-bottom: 15px;
}

@keyframes spinSmooth {
  from {
    transform: rotate(0deg) scale(1);
  }
  50% {
    transform: rotate(180deg) scale(1.1);
  }
  to {
    transform: rotate(360deg) scale(1);
  }
}

.close-viewer {
  background: #dc3545 !important;
}

.close-viewer:hover {
  background: #c82333 !important;
}

/* Capa de enlaces */
.pdf-interactive-layer {
  position: absolute;
  top: 0;
  left: 0;
  pointer-events: none;
  z-index: 10;
  transition: opacity var(--transition-fast);
}

.pdf-link-area {
  position: absolute;
  cursor: pointer;
  transition: all var(--transition-smooth);
  pointer-events: auto;
  border-radius: 4px;
}

.pdf-link-area.url-link {
  background: rgba(0, 123, 255, 0.15);
  border: 1px solid rgba(0, 123, 255, 0.4);
}

.pdf-link-area.url-link:hover {
  background: rgba(0, 123, 255, 0.35);
  border: 1px solid rgba(0, 123, 255, 0.8);
}

.pdf-link-area.email-link {
  background: rgba(40, 167, 69, 0.15);
  border: 1px solid rgba(40, 167, 69, 0.4);
}

.pdf-link-area.email-link:hover {
  background: rgba(40, 167, 69, 0.35);
  border: 1px solid rgba(40, 167, 69, 0.8);
}

.pdf-link-area.paypal-link {
  background: rgba(0, 156, 222, 0.15);
  border: 1px solid rgba(0, 156, 222, 0.4);
}

.pdf-link-area.paypal-link:hover {
  background: rgba(0, 156, 222, 0.35);
  border: 1px solid rgba(0, 156, 222, 0.8);
}

.pdf-link-area.social-link {
  background: rgba(111, 66, 193, 0.15);
  border: 1px solid rgba(111, 66, 193, 0.4);
}

.pdf-link-area.social-link:hover {
  background: rgba(111, 66, 193, 0.35);
  border: 1px solid rgba(111, 66, 193, 0.8);
}

.pdf-link-area.phone-link {
  background: rgba(255, 193, 7, 0.15);
  border: 1px solid rgba(255, 193, 7, 0.4);
}

.pdf-link-area.phone-link:hover {
  background: rgba(255, 193, 7, 0.35);
  border: 1px solid rgba(255, 193, 7, 0.8);
}

/* Tooltip de enlaces */
.link-tooltip {
  position: fixed;
  background: var(--surface-glass-dark);
  backdrop-filter: blur(10px);
  color: var(--color-on-dark);
  padding: 10px 18px;
  border-radius: 25px;
  font-size: 13px;
  z-index: 10000;
  pointer-events: none;
  white-space: nowrap;
  max-width: 400px;
  overflow: hidden;
  text-overflow: ellipsis;
  font-family: monospace;
  box-shadow: var(--shadow-md);
  animation: tooltipFadeIn var(--transition-fast);
  border-left: 3px solid;
}

@keyframes tooltipFadeIn {
  from {
    opacity: 0;
    transform: translateY(5px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.link-tooltip.url-tooltip {
  border-left-color: #007bff;
}

.link-tooltip.email-tooltip {
  border-left-color: #28a745;
}

.link-tooltip.paypal-tooltip {
  border-left-color: #009cde;
}

.link-tooltip.social-tooltip {
  border-left-color: #6f42c1;
}

.link-tooltip.phone-tooltip {
  border-left-color: #ffc107;
}

/* Indicador de página */
.page-indicator {
  position: absolute;
  bottom: 20px;
  left: 50%;
  transform: translateX(-50%);
  background: rgba(0, 0, 0, 0.75);
  backdrop-filter: blur(10px);
  color: var(--color-on-dark);
  padding: 8px 18px;
  border-radius: var(--radius-pill);
  font-size: 13px;
  font-weight: 500;
  pointer-events: none;
  z-index: 10;
  transition:
    opacity var(--transition-base),
    transform var(--transition-base);
  letter-spacing: 0.5px;
  box-shadow: var(--shadow-sm);
}

/* Notificación de zoom */
.zoom-toast {
  position: fixed;
  top: 100px;
  right: 20px;
  background: rgba(0, 0, 0, 0.85);
  backdrop-filter: blur(10px);
  color: var(--color-on-dark);
  padding: 10px 20px;
  border-radius: var(--radius-pill);
  font-size: 14px;
  font-weight: 500;
  z-index: 10001;
  pointer-events: none;
  animation: zoomToastFade 1s var(--transition-smooth);
  box-shadow: var(--shadow-sm);
}

@keyframes zoomToastFade {
  0% {
    opacity: 0;
    transform: translateX(30px) scale(0.9);
  }
  15% {
    opacity: 1;
    transform: translateX(0) scale(1);
  }
  85% {
    opacity: 1;
    transform: translateX(0) scale(1);
  }
  100% {
    opacity: 0;
    transform: translateX(30px) scale(0.9);
  }
}

/* ========== REPRODUCTOR DE MÚSICA ========== */
.music-player-fixed {
  position: fixed;
  bottom: 25px;
  right: 25px;
  z-index: 1000;
  animation: slideInRight 0.5s var(--transition-smooth);
}

@keyframes slideInRight {
  from {
    opacity: 0;
    transform: translateX(100px);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

#musicToggle {
  border-radius: 50px;
  padding: 12px 24px;
  box-shadow: var(--shadow-md);
  transition: all var(--transition-smooth);
  font-weight: 500;
}

#musicToggle:hover {
  transform: scale(1.05);
  box-shadow: var(--shadow-lg);
}

#musicToggle:active {
  transform: scale(0.95);
}

/* ========== REVEAL ON SCROLL (progressive enhancement) ========== */
@media (prefers-reduced-motion: no-preference) {
  .book-item.reveal {
    opacity: 0;
    transform: translateY(28px);
    transition:
      opacity 0.55s ease-out,
      transform 0.55s ease-out;
    will-change: opacity, transform;
  }

  .book-item.reveal.revealed {
    opacity: 1;
    transform: none;
  }
}

/* ========== SCROLLBAR ========== */
::-webkit-scrollbar {
  width: 10px;
  height: 10px;
}

::-webkit-scrollbar-track {
  background: rgba(0, 0, 0, 0.1);
  border-radius: 10px;
}

::-webkit-scrollbar-thumb {
  background: rgba(255, 255, 255, 0.3);
  border-radius: 10px;
}

::-webkit-scrollbar-thumb:hover {
  background: rgba(255, 255, 255, 0.5);
}

/* ========== SCROLL TO TOP ========== */
.scroll-top {
  position: fixed;
  bottom: 25px;
  left: 25px;
  width: 45px;
  height: 45px;
  background: rgba(255, 255, 255, 0.9);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition-smooth);
  z-index: 1000;
  box-shadow: var(--shadow-sm);
}

.scroll-top.show {
  opacity: 1;
  visibility: visible;
}

.scroll-top:hover {
  transform: translateY(-5px);
  background: #ffffff;
}

.scroll-top:active {
  transform: translateY(-2px) scale(0.95);
}

/* ========== CONTADOR DE ENLACES ========== */
.links-count {
  background: rgba(255, 255, 255, 0.2);
  padding: 2px 8px;
  border-radius: var(--radius-lg);
  font-size: 11px;
  margin-left: 5px;
}

/* ========== EFECTO VIDRIO ESMERILADO ========== */
.glass-effect {
  background: rgba(255, 255, 255, 0.1);
  backdrop-filter: blur(10px);
  border-radius: var(--radius-lg);
  border: 1px solid rgba(255, 255, 255, 0.2);
}

/* ========== BOTÓN CTA DE ADMIN (navbar) ========== */
.btn-admin-cta {
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
  background: rgba(255, 255, 255, 0.15);
  color: var(--color-on-dark);
  border: 1px solid rgba(255, 255, 255, 0.35);
  backdrop-filter: blur(8px);
  padding: 10px 22px;
  border-radius: var(--radius-pill);
  font-weight: 600;
  font-size: var(--font-size-md);
  letter-spacing: 0.5px;
  cursor: pointer;
  box-shadow: var(--shadow-sm);
  transition: all var(--transition-smooth);
}

.btn-admin-cta:hover {
  background: rgba(255, 255, 255, 0.28);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
  color: var(--color-on-dark);
}

.btn-admin-cta:active {
  transform: translateY(0) scale(0.97);
  transition-duration: var(--transition-fast);
}

/* Offset bajo navbar fijo (sustituye estilo inline) */
.hero-section.nav-offset {
  margin-top: 56px;
}

/* ========== TARJETA DE LIBRO: FOCO TECLADO ========== */
.book-card:focus-visible {
  outline: 3px solid var(--color-on-dark);
  outline-offset: 3px;
  transform: translateY(-6px) scale(1.01);
  background: #ffffff;
}

/* ========== ESTADO VACÍO (sin libros) ========== */
.empty-state {
  background: var(--surface-glass);
  backdrop-filter: blur(10px);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
  padding: 60px 30px;
  text-align: center;
}

.empty-state i {
  font-size: 56px;
  color: var(--color-primary);
  opacity: 0.85;
  margin-bottom: var(--space-md);
  animation: floatSoft 3s ease-in-out infinite;
}

.empty-state h2 {
  font-size: var(--font-size-xl);
  font-weight: 700;
  color: var(--color-text);
  margin-bottom: var(--space-sm);
}

.empty-state p {
  color: var(--color-text-muted);
  margin: 0;
}

@keyframes floatSoft {
  0%,
  100% {
    transform: translateY(0);
  }
  50% {
    transform: translateY(-6px);
  }
}

/* ========== RESPONSIVE ========== */
@media (max-width: 768px) {
  .hero-title {
    font-size: 2rem;
  }
  .hero-subtitle {
    font-size: var(--font-size-base);
  }
  .hero-stats {
    gap: 8px;
  }
  .hero-stat {
    font-size: var(--font-size-xs);
    padding: 6px 12px;
  }
  .hero-stat strong {
    font-size: var(--font-size-base);
  }
  .hero-stat-divider {
    display: none;
  }
  .results-count {
    font-size: var(--font-size-sm);
    margin-top: -6px;
  }
  .pdf-toolbar {
    flex-direction: column;
  }
  .pdf-title {
    white-space: normal;
    text-align: center;
  }
  .pdf-controls {
    justify-content: center;
  }
  .music-player-fixed {
    bottom: 15px;
    right: 15px;
  }
  #musicToggle {
    padding: 8px 16px;
    font-size: 12px;
  }
  .book-title {
    font-size: var(--font-size-base);
  }
  .link-tooltip {
    font-size: 10px;
    max-width: 250px;
    white-space: normal;
    word-break: break-all;
  }
}

/* ========== MEJORAS PARA DISPOSITIVOS MÓVILES ========== */

/* Vista responsiva del visor PDF */
@media (max-width: 768px) {
  .pdf-viewer-modal {
    width: 100% !important;
    height: 100% !important;
    top: 0 !important;
    left: 0 !important;
    border-radius: 0 !important;
  }

  .pdf-toolbar {
    flex-direction: column !important;
    padding: 10px !important;
    gap: 10px !important;
  }

  .pdf-title {
    font-size: 14px !important;
    text-align: center !important;
    width: 100% !important;
  }

  .pdf-controls {
    flex-wrap: wrap !important;
    justify-content: center !important;
    gap: 8px !important;
  }

  .pdf-controls button,
  .pdf-controls span {
    font-size: 12px !important;
    padding: 6px 12px !important;
  }

  .pdf-controls input {
    width: 50px !important;
    font-size: 12px !important;
  }

  .pdf-container {
    height: calc(100vh - 120px) !important;
    -webkit-overflow-scrolling: touch !important;
  }

  /* Áreas de enlace más grandes para touch */
  .pdf-link-area {
    min-width: 44px !important;
    min-height: 44px !important;
    background: rgba(0, 123, 255, 0.15) !important;
  }

  /* Mejorar legibilidad del texto en el canvas */
  #pdfCanvas {
    image-rendering: -webkit-optimize-contrast !important;
    image-rendering: crisp-edges !important;
  }

  /* Ajustar grid de libros para móvil */
  .books-grid .row {
    display: grid !important;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)) !important;
    gap: 15px !important;
  }

  .book-card {
    margin: 0 !important;
  }

  /* Hero section más compacta */
  .hero-section {
    padding: 40px 20px !important;
  }

  .hero-title {
    font-size: 24px !important;
  }

  .hero-subtitle {
    font-size: 14px !important;
  }

  /* Filtros mejorados */
  .filters-section {
    padding: 0 15px !important;
  }

  /* Música flotante */
  .music-player-fixed {
    bottom: 70px !important;
    right: 10px !important;
  }

  .music-player-fixed button {
    padding: 8px 12px !important;
    font-size: 12px !important;
  }
}

/* Para tablets */
@media (min-width: 769px) and (max-width: 1024px) {
  .pdf-controls button,
  .pdf-controls span {
    font-size: 13px !important;
    padding: 8px 14px !important;
  }

  .books-grid .row {
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr)) !important;
  }
}

/* Prevenir selección de texto durante interacciones táctiles */
.pdf-link-area {
  -webkit-tap-highlight-color: transparent !important;
  touch-action: manipulation !important;
}

/* Mejorar scroll en móvil */
.pdf-container {
  overflow-y: auto !important;
  -webkit-overflow-scrolling: touch !important;
  scroll-behavior: smooth !important;
}

/* Indicador de página más visible en móvil */
.page-indicator {
  bottom: 80px !important;
  font-size: 14px !important;
  padding: 8px 16px !important;
  background: rgba(0, 0, 0, 0.85) !important;
  backdrop-filter: blur(10px) !important;
  border-radius: var(--radius-pill) !important;
}

/* ========== HERO STATS ========== */
.hero-stats {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 14px;
  flex-wrap: wrap;
  margin-top: 22px;
  animation: fadeInUp 0.8s ease;
}

.hero-stat {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: rgba(255, 255, 255, 0.12);
  border: 1px solid rgba(255, 255, 255, 0.25);
  backdrop-filter: blur(8px);
  padding: 8px 18px;
  border-radius: var(--radius-pill);
  font-size: var(--font-size-md);
  color: var(--color-on-dark);
}

.hero-stat strong {
  font-weight: 700;
  font-size: var(--font-size-lg);
}

.hero-stat i {
  opacity: 0.9;
}

.hero-stat-divider {
  width: 1px;
  height: 22px;
  background: rgba(255, 255, 255, 0.3);
}

.hero-scroll-cue {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  margin-top: 28px;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.15);
  border: 1px solid rgba(255, 255, 255, 0.35);
  color: var(--color-on-dark);
  transition:
    background var(--transition-base),
    transform var(--transition-base);
  animation: cueBounce 2s infinite ease-in-out;
}

.hero-scroll-cue:hover {
  background: rgba(255, 255, 255, 0.3);
  color: var(--color-on-dark);
  transform: translateY(-3px);
}

@keyframes cueBounce {
  0%,
  100% {
    transform: translateY(0);
  }
  50% {
    transform: translateY(6px);
  }
}

/* ========== CHIPS DE CATEGORÍAS ========== */
.chips-row {
  display: flex;
  gap: 10px;
  flex-wrap: nowrap;
  overflow-x: auto;
  padding: 16px 2px 6px;
  scrollbar-width: thin;
  -webkit-overflow-scrolling: touch;
}

.chip {
  flex: 0 0 auto;
  padding: 7px 16px;
  border-radius: var(--radius-pill);
  border: 1.5px solid var(--border-color);
  background: #ffffff;
  color: var(--color-text-soft);
  font-size: var(--font-size-sm);
  font-weight: 500;
  cursor: pointer;
  white-space: nowrap;
  transition: all var(--transition-fast);
}

.chip:hover {
  border-color: var(--color-primary);
  color: var(--color-primary);
  transform: translateY(-2px);
  box-shadow: var(--shadow-sm);
}

.chip.is-active {
  background: var(--gradient-brand);
  color: var(--color-on-dark);
  border-color: transparent;
  box-shadow: var(--shadow-sm);
}

.chip:focus-visible {
  outline-offset: 2px;
}

/* ========== CONTADOR DE RESULTADOS ========== */
.results-count {
  color: var(--color-text-muted);
  font-size: var(--font-size-md);
  margin-top: -12px;
  margin-bottom: 20px;
  padding-left: 6px;
  min-height: 1.2em;
}

.results-count strong {
  color: var(--color-primary-dark);
}

/* ========== BOTÓN LIMPIAR BÚSQUEDA ========== */
.search-box input {
  padding-right: 38px;
}

.clear-search-btn {
  position: absolute;
  right: 12px;
  top: 50%;
  transform: translateY(-50%);
  background: transparent;
  border: none;
  color: var(--color-text-faint);
  cursor: pointer;
  font-size: 1rem;
  line-height: 1;
  padding: 4px;
  transition:
    color var(--transition-fast),
    transform var(--transition-fast);
}

.clear-search-btn:hover {
  color: var(--color-primary);
  transform: translateY(-50%) scale(1.15);
}

/* ========== BADGE NUEVO Y CHIP DE CATEGORÍA EN TARJETA ========== */
.book-badge-new {
  left: 15px;
  right: auto;
  top: 15px;
  background: linear-gradient(135deg, #f6ad55, #ed8936);
  font-weight: 600;
  box-shadow: var(--shadow-sm);
}

.book-category-chip {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.3px;
  color: var(--color-primary-dark);
  background: rgba(102, 126, 234, 0.12);
  border: 1px solid rgba(102, 126, 234, 0.25);
  padding: 3px 10px;
  border-radius: var(--radius-pill);
  margin-bottom: 8px;
}

.book-category-chip i {
  font-size: 10px;
}

/* ========== ESTADO SIN RESULTADOS ========== */
.no-results-state[hidden] {
  display: none;
}

.btn-reset-filters {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-top: 18px;
  background: var(--gradient-brand);
  color: var(--color-on-dark);
  border: none;
  padding: 10px 24px;
  border-radius: var(--radius-pill);
  font-weight: 600;
  font-size: var(--font-size-md);
  cursor: pointer;
  box-shadow: var(--shadow-md);
  transition: all var(--transition-smooth);
}

.btn-reset-filters:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

.btn-reset-filters:active {
  transform: scale(0.97);
  transition-duration: var(--transition-fast);
}

/* ========== FOOTER ========== */
.site-footer {
  position: relative;
  z-index: 1;
  margin-top: 40px;
  padding: 28px 0 95px;
  text-align: center;
  color: rgba(255, 255, 255, 0.92);
  text-shadow: 1px 1px 3px rgba(0, 0, 0, 0.25);
}

.site-footer p {
  margin: 4px 0;
}

.site-footer i {
  margin-right: 8px;
}

.site-footer-copy {
  font-size: var(--font-size-sm);
  opacity: 0.8;
}

/* ========== MODO SIN ANIMACIONES (config admin) ========== */
body.no-anim .animated-bg {
  display: block; /* mantiene el degradado estático, solo se pausan animaciones */
}
body.no-anim .animated-bg::before {
  animation: none !important;
}

body.no-anim .wave,
body.no-anim .bubble,
body.no-anim .bubble-small,
body.no-anim .particle {
  display: none;
}

body.no-anim *,
body.no-anim *::before,
body.no-anim *::after {
  animation: none !important;
  transition-duration: 0.01ms !important;
}

/* ========== ACCESIBILIDAD: MOVIMIENTO REDUCIDO ========== */
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}