/* ==========================================================================
   Libro de Viajes - Styles
   ========================================================================== */

/* --------------------------------------------------------------------------
   CSS Custom Properties
   -------------------------------------------------------------------------- */
:root {
  /* Colors */
  --color-pergamino: #F5E6D3;
  --color-pergamino-dark: #2A2520;
  --color-tinta: #4A3728;
  --color-tinta-light: #E8DDD0;
  --color-acento: #B85450;
  --color-agua: #7B9BA6;
  --color-oro: #C4A35A;
  --color-sepia: #8B7355;

  /* Typography */
  --font-titulo: 'Cormorant Garamond', Georgia, serif;
  --font-poesia: 'EB Garamond', Georgia, serif;
  --font-ui: 'Inter', -apple-system, sans-serif;

  /* Spacing */
  --spacing-verso: 0.35em;
  --spacing-estrofa: 1.8em;
  --spacing-canto: 4rem;
  --spacing-viaje: 6rem;

  /* Animation */
  --ease-smooth: cubic-bezier(0.4, 0, 0.2, 1);
  --ease-out: cubic-bezier(0, 0, 0.2, 1);
  --duration-reveal: 0.6s;
  --duration-fast: 0.2s;

  /* Layout */
  --max-width-content: 65ch;
  --page-padding: clamp(1.5rem, 5vw, 4rem);
}

/* Night mode */
.night-mode {
  --color-pergamino: #1A1814;
  --color-tinta: #E8DDD0;
  --color-acento: #D4807C;
}

/* --------------------------------------------------------------------------
   Reset & Base
   -------------------------------------------------------------------------- */
*, *::before, *::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-snap-type: y proximity;
}

body {
  margin: 0;
  padding: 0;
  font-family: var(--font-poesia);
  font-size: clamp(1rem, 2.5vw, 1.25rem);
  line-height: 1.7;
  color: var(--color-tinta);
  background-color: var(--color-pergamino);
  transition: background-color var(--duration-reveal) var(--ease-smooth),
              color var(--duration-reveal) var(--ease-smooth);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* Screen reader only */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* --------------------------------------------------------------------------
   Progress Bar
   -------------------------------------------------------------------------- */
.progress-bar {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 3px;
  background: transparent;
  z-index: 1000;
}

.progress-fill {
  height: 100%;
  width: 0%;
  background: linear-gradient(90deg, var(--color-acento), var(--color-oro));
  transition: width 0.1s linear;
}

/* --------------------------------------------------------------------------
   Navigation
   -------------------------------------------------------------------------- */
.nav-chapters {
  position: fixed;
  top: var(--page-padding);
  left: var(--page-padding);
  z-index: 100;
}

.nav-toggle {
  width: 44px;
  height: 44px;
  padding: 12px;
  background: var(--color-pergamino);
  border: 1px solid var(--color-sepia);
  border-radius: 50%;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all var(--duration-fast) var(--ease-smooth);
  opacity: 0.7;
}

.nav-toggle:hover,
.nav-toggle:focus {
  opacity: 1;
  transform: scale(1.05);
}

.nav-toggle-icon {
  width: 18px;
  height: 2px;
  background: var(--color-tinta);
  position: relative;
}

.nav-toggle-icon::before,
.nav-toggle-icon::after {
  content: '';
  position: absolute;
  width: 100%;
  height: 100%;
  background: inherit;
  left: 0;
}

.nav-toggle-icon::before { top: -6px; }
.nav-toggle-icon::after { top: 6px; }

.chapter-list {
  position: absolute;
  top: 54px;
  left: 0;
  margin: 0;
  padding: 1rem 0;
  list-style: none;
  background: var(--color-pergamino);
  border: 1px solid var(--color-sepia);
  border-radius: 8px;
  min-width: 280px;
  box-shadow: 0 4px 20px rgba(0,0,0,0.1);
  opacity: 0;
  visibility: hidden;
  transform: translateY(-10px);
  transition: all var(--duration-fast) var(--ease-smooth);
}

.chapter-list:not([hidden]) {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.chapter-list li {
  margin: 0;
}

.chapter-list a {
  display: block;
  padding: 0.75rem 1.5rem;
  color: var(--color-tinta);
  text-decoration: none;
  font-family: var(--font-ui);
  font-size: 0.875rem;
  transition: background var(--duration-fast);
}

.chapter-list a:hover,
.chapter-list a:focus {
  background: rgba(0,0,0,0.05);
}

/* --------------------------------------------------------------------------
   Controls
   -------------------------------------------------------------------------- */
.controls {
  position: fixed;
  top: var(--page-padding);
  right: var(--page-padding);
  z-index: 100;
  display: flex;
  gap: 0.5rem;
}

.control-btn {
  width: 44px;
  height: 44px;
  padding: 0;
  background: var(--color-pergamino);
  border: 1px solid var(--color-sepia);
  border-radius: 50%;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-tinta);
  transition: all var(--duration-fast) var(--ease-smooth);
  opacity: 0.7;
}

.control-btn:hover,
.control-btn:focus {
  opacity: 1;
  transform: scale(1.05);
}

.control-btn.active {
  background: var(--color-tinta);
  color: var(--color-pergamino);
  opacity: 1;
}

/* Zen mode */
.zen-mode .nav-chapters,
.zen-mode .controls,
.zen-mode .progress-bar {
  opacity: 0;
  pointer-events: none;
}

.zen-mode:hover .nav-chapters,
.zen-mode:hover .controls,
.zen-mode:hover .progress-bar {
  opacity: 1;
  pointer-events: auto;
}

/* --------------------------------------------------------------------------
   Page Layout
   -------------------------------------------------------------------------- */
.page {
  min-height: 100vh;
  padding: var(--page-padding);
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  scroll-snap-align: start;
}

/* --------------------------------------------------------------------------
   Portada
   -------------------------------------------------------------------------- */
.portada {
  text-align: center;
  background: linear-gradient(
    to bottom,
    var(--color-pergamino) 0%,
    color-mix(in srgb, var(--color-pergamino) 95%, var(--color-oro)) 100%
  );
}

.portada-content {
  max-width: 600px;
}

.titulo-libro {
  font-family: var(--font-titulo);
  font-size: clamp(2.5rem, 8vw, 4.5rem);
  font-weight: 400;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  margin: 0 0 1rem;
  color: var(--color-acento);
}

.autor {
  font-family: var(--font-titulo);
  font-size: clamp(1.25rem, 4vw, 1.75rem);
  font-weight: 600;
  letter-spacing: 0.1em;
  margin: 0 0 2rem;
}

.ilustrador {
  font-family: var(--font-titulo);
  font-size: clamp(1rem, 3vw, 1.25rem);
  font-style: italic;
  margin: 0 0 0.5rem;
  color: var(--color-sepia);
}

.edicion {
  font-family: var(--font-ui);
  font-size: 0.875rem;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--color-sepia);
  margin: 0;
}

/* --------------------------------------------------------------------------
   Ilustraciones
   -------------------------------------------------------------------------- */
.ilustracion {
  background: var(--color-pergamino);
  padding: 2rem;
}

.ilustracion-figura {
  margin: 0;
  max-width: 90vmin;
  max-height: 85vh;
}

.ilustracion-img {
  display: block;
  max-width: 100%;
  max-height: 75vh;
  width: auto;
  height: auto;
  object-fit: contain;
  border: 8px solid white;
  box-shadow: 0 4px 30px rgba(0,0,0,0.15);
}

.ilustracion-caption {
  font-family: var(--font-ui);
  font-size: 0.875rem;
  text-align: center;
  margin-top: 1rem;
  color: var(--color-sepia);
  font-style: italic;
}

/* --------------------------------------------------------------------------
   Viajes (Sections)
   -------------------------------------------------------------------------- */
.viaje {
  scroll-margin-top: 2rem;
}

.viaje-header {
  text-align: center;
  background: linear-gradient(
    to bottom,
    var(--color-pergamino) 0%,
    color-mix(in srgb, var(--color-pergamino) 97%, var(--color-acento)) 100%
  );
}

.viaje-title {
  font-family: var(--font-titulo);
  font-size: clamp(1.5rem, 5vw, 2.5rem);
  font-weight: 400;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--color-acento);
  margin: 0;
  position: relative;
}

.viaje-title::after {
  content: '';
  display: block;
  width: 3rem;
  height: 1px;
  background: var(--color-oro);
  margin: 1.5rem auto 0;
}

/* --------------------------------------------------------------------------
   Cantos (Articles)
   -------------------------------------------------------------------------- */
.canto {
  text-align: left;
  align-items: flex-start;
  max-width: var(--max-width-content);
  margin: 0 auto;
  width: 100%;
}

.canto-number {
  font-family: var(--font-titulo);
  font-size: 1.5rem;
  font-weight: 400;
  text-align: center;
  width: 100%;
  margin: 0 0 2rem;
  color: var(--color-sepia);
}

/* --------------------------------------------------------------------------
   Verses
   -------------------------------------------------------------------------- */
.verses {
  width: 100%;
}

.verse {
  margin: 0;
  padding: var(--spacing-verso) 0;
  opacity: 0;
  transform: translateY(10px);
  transition: opacity var(--duration-reveal) var(--ease-out),
              transform var(--duration-reveal) var(--ease-out);
}

.verse.visible {
  opacity: 1;
  transform: translateY(0);
}

.verse.stanza-break {
  height: var(--spacing-estrofa);
  padding: 0;
}

/* Immediate visibility for no-JS */
.no-js .verse {
  opacity: 1;
  transform: none;
}

/* --------------------------------------------------------------------------
   Colofon
   -------------------------------------------------------------------------- */
.colofon {
  text-align: center;
  background: linear-gradient(
    to bottom,
    var(--color-pergamino) 0%,
    color-mix(in srgb, var(--color-pergamino) 90%, var(--color-sepia)) 100%
  );
}

.colofon-content {
  max-width: 400px;
  font-family: var(--font-ui);
  font-size: 0.875rem;
  line-height: 1.8;
}

.colofon-content p {
  margin: 0 0 1rem;
}

.colofon-edita {
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
}

.colofon-direccion {
  color: var(--color-sepia);
}

.colofon-isbn {
  font-weight: 500;
}

.colofon-papel {
  text-transform: uppercase;
  letter-spacing: 0.15em;
  font-size: 0.75rem;
  color: var(--color-sepia);
  margin-top: 2rem !important;
}

/* --------------------------------------------------------------------------
   Autores
   -------------------------------------------------------------------------- */
.autores {
  text-align: center;
  background: var(--color-pergamino);
}

.autores-content {
  max-width: 600px;
}

.autores-titulo {
  font-family: var(--font-titulo);
  font-size: 1.75rem;
  font-weight: 400;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--color-acento);
  margin: 0 0 3rem;
}

.autor-bio {
  margin-bottom: 2.5rem;
  text-align: left;
}

.autor-bio h3 {
  font-family: var(--font-titulo);
  font-size: 1.25rem;
  font-weight: 600;
  margin: 0 0 0.25rem;
}

.autor-anos {
  font-family: var(--font-ui);
  font-size: 0.875rem;
  color: var(--color-sepia);
  margin: 0 0 1rem;
}

.autor-bio p:last-child {
  margin: 0;
  color: var(--color-tinta);
}

.edicion-info {
  font-style: italic;
  color: var(--color-sepia);
  border-top: 1px solid var(--color-sepia);
  padding-top: 2rem;
  margin-top: 2rem;
}

/* --------------------------------------------------------------------------
   Responsive
   -------------------------------------------------------------------------- */
@media (max-width: 768px) {
  :root {
    --page-padding: 1.25rem;
  }

  .nav-chapters {
    top: 1rem;
    left: 1rem;
  }

  .controls {
    top: 1rem;
    right: 1rem;
  }

  .chapter-list {
    min-width: calc(100vw - 2rem);
    left: 0;
  }

  .canto {
    padding-left: 0.5rem;
    padding-right: 0.5rem;
  }

  .ilustracion-img {
    border-width: 4px;
  }
}

@media (max-width: 480px) {
  .titulo-libro {
    letter-spacing: 0.08em;
  }

  .viaje-title {
    letter-spacing: 0.06em;
  }
}

/* --------------------------------------------------------------------------
   Print
   -------------------------------------------------------------------------- */
@media print {
  .progress-bar,
  .nav-chapters,
  .controls {
    display: none;
  }

  .page {
    min-height: auto;
    page-break-after: always;
  }

  .verse {
    opacity: 1;
    transform: none;
  }
}

/* --------------------------------------------------------------------------
   Animations
   -------------------------------------------------------------------------- */
@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(15px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes pulse {
  0%, 100% { opacity: 0.7; }
  50% { opacity: 1; }
}

/* Initial page load animation */
.portada-content {
  animation: fadeIn 1s var(--ease-out) 0.3s both;
}

/* --------------------------------------------------------------------------
   Focus styles
   -------------------------------------------------------------------------- */
:focus-visible {
  outline: 2px solid var(--color-acento);
  outline-offset: 2px;
}

/* --------------------------------------------------------------------------
   Selection
   -------------------------------------------------------------------------- */
::selection {
  background: var(--color-oro);
  color: var(--color-pergamino-dark);
}