/* Blanco y negro puros a propósito: el UX/UI se decide desde aquí. Los errores
   se distinguen por estructura (borde, peso), no por color. */

:root {
  --ink: #000;
  --paper: #fff;
  --muted: #595959; /* 7:1 sobre blanco, AAA */
  --line: #d4d4d4;

  --space: 1rem;
  --radius: 4px;
  --page-width: 36rem;
  --touch: 44px;
}

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

*::-webkit-scrollbar {
  width: 16px;
}

*::-webkit-scrollbar-track {
  border-radius: 8px;
}

*::-webkit-scrollbar-thumb {
  height: 56px;
  border-radius: 8px;
  border: 4px solid transparent;
  background-clip: content-box;
  background-color: #888;
}

*::-webkit-scrollbar-thumb:hover {
  background-color: #555;
}

body {
  font-family: Arial, Helvetica, sans-serif;
  color: var(--ink);
  background: var(--paper);
  padding: 0 var(--space);
}

.page {
  max-width: var(--page-width);
  margin: 0 auto;
  padding: var(--space) 0 3rem;
}

.page-wide {
  max-width: 60rem;
}

.text-link,
.text-link-button {
  color: var(--ink);
  text-decoration: underline;
}

.text-link-button {
  padding: 0;
  border: none;
  background: none;
  font: inherit;
  cursor: pointer;
}

:where(button, input):focus-visible {
  outline: 2px solid var(--ink);
  outline-offset: 2px;
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  overflow: hidden;
  clip-path: inset(50%);
  white-space: nowrap;
  border: 0;
}

/* Botones: un solo tratamiento, borde negro que se invierte al pasar. La
   jerarquía la marca el tamaño. */

.scan-button {
  border: 1px solid var(--ink);
  border-radius: var(--radius);
  background: var(--paper);
  color: var(--ink);
  font: inherit;
  cursor: pointer;
}

.scan-button:hover:not(:disabled) {
  background: var(--ink);
  color: var(--paper);
}

.scan-button:active:not(:disabled) {
  transform: translateY(1px);
}

.scan-button:disabled {
  border-color: var(--line);
  color: var(--muted);
  cursor: default;
}

.scan-button {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  width: 100%;
  min-height: 52px;
  padding: 0 1rem;
  font-size: 1.0625rem;
  font-weight: bold;
}

.scan-button svg {
  flex: none;
}

.brand {
  text-align: center;
  margin-bottom: 2.5rem;
}

.brand-logo {
  display: block;
  aspect-ratio: 1; /* reserva el hueco: el logo no empuja el título al cargar */
  width: auto;
  height: 140px;
  margin: 0 auto 0.5rem;
  object-fit: contain;
}

.brand-title {
  font-size: 1.75rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
}

.brand-link {
  display: block;
  color: inherit;
  text-decoration: none;
}

.brand-link:focus-visible {
  outline: 2px solid var(--ink);
  outline-offset: 4px;
  border-radius: var(--radius);
}

.page-links {
  margin-top: 2.5rem;
  text-align: center;
}

.library-grid {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(10rem, 1fr));
  gap: 1rem;
  margin-bottom: 1.5rem;
}

.page-not-found {
  padding-top: 3rem;
}

.search {
  margin-bottom: 1.5rem;
}

.search-title {
  font-size: 1.125rem;
  margin-bottom: 0.75rem;
}

.scan-options {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.75rem;
}

.scan-option {
  flex-direction: column;
  gap: 0.5rem;
  min-height: 6rem;
  padding: 0.75rem 0.5rem;
  font-size: 1rem;
  line-height: 1.2;
}

.search-divider {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin: 1rem 0;
  color: var(--muted);
  font-size: 0.8125rem;
}

.search-divider::before,
.search-divider::after {
  content: '';
  flex: 1;
  height: 1px;
  background: var(--line);
}

.search-switch {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  width: 100%;
  min-height: var(--touch);
  padding: 0 1rem;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--paper);
  color: var(--muted);
  font: inherit;
  cursor: pointer;
}

.search-switch:hover {
  border-color: var(--ink);
  color: var(--ink);
}

.status {
  margin-bottom: 1rem;
}

.status-message {
  display: flex;
  align-items: flex-start;
  gap: 0.5rem;
  padding: 0.5rem 0;
}

.status-icon {
  flex: none;
  font-size: 1rem;
  line-height: 1.3;
}

.status-message-error {
  font-weight: bold;
}

.status-message-notice {
  color: var(--muted);
  font-size: 0.875rem;
  font-style: italic;
}

.spinner {
  display: flex;
  justify-content: center;
  padding: 1.5rem 0;
}

.spinner-ring {
  width: 1.75rem;
  height: 1.75rem;
  border: 2px solid var(--line);
  border-top-color: var(--ink);
  border-radius: 50%;
  animation: spinner-turn 0.8s linear infinite;
}

@keyframes spinner-turn {
  to {
    transform: rotate(360deg);
  }
}

@media (prefers-reduced-motion: reduce) {
  .spinner-ring {
    border-color: var(--ink);
    animation: spinner-pulse 1.2s ease-in-out infinite;
  }

  @keyframes spinner-pulse {
    50% {
      opacity: 0.3;
    }
  }
}

.result-region:focus {
  outline: none;
}

.result-region:focus-visible {
  outline: 2px solid var(--ink);
  outline-offset: 4px;
  border-radius: var(--radius);
}

.book {
  display: grid;
  gap: 1.5rem;
}

.book-cover {
  display: block;
  width: min(60vw, 14rem);
  aspect-ratio: 2 / 3;
  margin: 0 auto;
  border: 1px solid var(--line);
  border-radius: 2px;
  background: var(--paper);
  object-fit: cover;
}

.book-cover-empty {
  display: grid;
  place-items: center;
  color: var(--line);
}

.book-body {
  min-width: 0;
  max-width: 40rem;
}

.book-title {
  font-size: 1.5rem;
  line-height: 1.2;
}

.book-subtitle {
  margin-top: 0.35rem;
  color: var(--muted);
  font-size: 1.0625rem;
}

.book-authors {
  margin-top: 0.5rem;
  font-size: 1.0625rem;
}

.book-meta {
  margin-top: 1rem;
}

.book-meta-line {
  color: var(--muted);
  font-size: 0.875rem;
}

.book-meta-line + .book-meta-line {
  margin-top: 0.25rem;
}

.book-origin {
  margin-top: 0.75rem;
  color: var(--muted);
  font-size: 0.875rem;
  font-style: italic;
}

.book-links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.25rem 1rem;
  margin-top: 1rem;
  font-size: 0.875rem;
}

.book-links a {
  display: inline-flex;
  align-items: center;
  gap: 0.2rem;
}

.book-description {
  margin-top: 1.5rem;
  padding-top: 1.25rem;
  border-top: 1px solid var(--line);
  font-size: 0.9375rem;
  line-height: 1.55;
}

.book-description p {
  white-space: pre-wrap;
}

.book-excerpt {
  margin-bottom: 1rem;
  padding: 0.25rem 0.75rem;
  border-left: 3px solid var(--line);
  color: var(--muted);
  font-style: italic;
}

@media (min-width: 40rem) {
  .book {
    grid-template-columns: 14rem minmax(0, 1fr);
    gap: 2rem;
    align-items: start;
  }

  .book-cover {
    position: sticky;
    top: 1rem;
    width: 14rem;
    margin: 0;
  }
}

.modal-backdrop {
  position: fixed;
  inset: 0;
  z-index: 1000;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--space);
  overscroll-behavior: contain;
  background: rgba(0, 0, 0, 0.9);
}

.modal {
  position: relative;
}

.modal-close {
  position: absolute;
  top: var(--space);
  right: var(--space);
  display: grid;
  place-items: center;
  width: var(--touch);
  height: var(--touch);
  border: 1px solid var(--line);
  border-radius: 50%;
  background: var(--paper);
  color: var(--ink);
  cursor: pointer;
}

.modal-close:hover {
  border-color: var(--ink);
}

.manual-dialog {
  width: min(24rem, 100%);
  padding: 1.5rem;
  border-radius: var(--radius);
  background: var(--paper);
  color: var(--ink);
}

.manual-form {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  text-align: center;
}

.manual-icon {
  display: flex;
  justify-content: center;
  padding-top: 0.75rem;
}

.manual-title {
  font-size: 1.25rem;
}

.manual-hint {
  margin-top: -0.35rem;
  color: var(--muted);
  font-size: 0.9rem;
}

.manual-input {
  min-height: 52px;
  margin-top: 0.5rem;
  padding: 0 0.75rem;
  border: 1px solid var(--ink);
  border-radius: var(--radius);
  background: var(--paper);
  color: var(--ink);
  font: inherit;
  font-size: 1.25rem;
  letter-spacing: 0.06em;
  text-align: center;
}

.manual-input[aria-invalid='true'] {
  border-width: 2px;
}

.manual-form .status-message {
  text-align: left;
  font-size: 0.9rem;
}

.scanner-fallback {
  flex-direction: column;
  gap: 0.75rem;
  color: var(--paper);
  text-align: center;
}

.scanner-fallback button:not(.text-link-button) {
  min-height: var(--touch);
  padding: 0 1rem;
  border-radius: var(--radius);
  border: 1px solid var(--paper);
  background: transparent;
  color: var(--paper);
}

/* El diálogo es la cámara: la barra y las indicaciones flotan sobre el vídeo.
   En escritorio se acota a 16:9; en móvil vertical llena la pantalla. */
.scanner-dialog {
  position: relative;
  width: min(40rem, calc(100vw - 2 * var(--space)), calc(85dvh * 16 / 9));
  aspect-ratio: 16 / 9;
  overflow: hidden;
  border-radius: var(--radius);
  background: #000;
  color: var(--paper);
}

.scanner-dialog .modal-close,
.scanner-help {
  position: absolute;
  background: rgba(0, 0, 0, 0.45);
  -webkit-backdrop-filter: blur(12px);
  backdrop-filter: blur(12px);
}

.scanner-dialog .modal-close {
  border-color: rgba(255, 255, 255, 0.35);
  color: var(--paper);
}

.scanner-dialog .modal-close:hover {
  border-color: var(--paper);
  background: var(--paper);
  color: var(--ink);
}

.scanner-help {
  left: 0;
  right: 0;
  bottom: 0;
  padding: 0.75rem var(--space);
  border-top: 1px solid rgba(255, 255, 255, 0.2);
  font-size: 0.8125rem;
}

.scanner-help p + p {
  margin-top: 0.35rem;
}

.scanner-error {
  position: absolute;
  inset: 0;
  display: grid;
  align-content: center;
  justify-items: center;
  gap: 1rem;
  padding: 4rem var(--space) var(--space);
  text-align: center;
}

.scanner-error .scan-button {
  width: auto;
}

.scanner-dialog .scan-button {
  border-color: var(--paper);
  background: transparent;
  color: var(--paper);
}

.scanner-dialog .scan-button:hover:not(:disabled) {
  background: var(--paper);
  color: var(--ink);
}

.scanner-dialog .scan-button:disabled {
  border-color: rgba(255, 255, 255, 0.4);
  color: rgba(255, 255, 255, 0.6);
}

.scanner-dialog :focus-visible {
  outline-color: var(--paper);
}

@media (max-width: 40rem) and (orientation: portrait) {
  .modal-backdrop:has(.scanner-dialog) {
    padding: 0;
  }

  .scanner-dialog {
    width: 100%;
    height: 100dvh;
    aspect-ratio: auto;
    border-radius: 0;
  }

  .scanner-dialog .modal-close {
    top: calc(var(--space) + env(safe-area-inset-top, 0px));
  }

  .scanner-help {
    padding-bottom: calc(0.75rem + env(safe-area-inset-bottom, 0px));
  }
}

.scanner-viewport {
  position: absolute;
  inset: 0;
}

/* contain en escritorio para no recortar el encuadre; cover solo en móvil
   vertical, donde el vídeo llena la pantalla. cropFrame lee el valor real. */
.scanner-video {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: contain;
  background: #000;
}

/* La sombra exterior gigante atenúa lo que queda fuera del marco: la guía se
   ve sobre cualquier fondo y dirige la vista. */
.scanner-frame,
.text-frame {
  position: absolute;
  border: 2px dashed var(--paper);
  border-radius: 2px;
  pointer-events: none;
  box-shadow:
    0 0 0 1px rgba(0, 0, 0, 0.75),
    inset 0 0 0 1px rgba(0, 0, 0, 0.75),
    0 0 0 9999px rgba(0, 0, 0, 0.45);
}

.scanner-frame {
  inset: 35% 10%;
  border-radius: var(--radius);
}

.scanner-meta {
  font-weight: bold;
}

@media (max-width: 40rem) and (orientation: portrait) {
  .scanner-video {
    object-fit: cover;
  }
}

/* Franja de una línea de texto: el recorte que se envía al OCR se calcula en
   JS desde la posición real de este elemento. */
.text-frame {
  inset: 44% 6%;
}

.text-read-button {
  margin-top: 0.75rem;
}

.text-scanner-message {
  font-weight: bold;
}

.library-item-link {
  display: block;
  border-radius: 2px;
}

.library-item-link:focus-visible {
  outline: 2px solid var(--ink);
  outline-offset: 3px;
}

.library-cover {
  display: block;
  width: 100%;
  aspect-ratio: 2 / 3;
  border: 1px solid var(--line);
  border-radius: 2px;
  background: var(--paper);
  object-fit: cover;
}

.library-cover-empty {
  display: grid;
  place-items: center;
  padding: 0.75rem;
  color: var(--ink);
  text-align: center;
  font-weight: bold;
  line-height: 1.25;
}

.library-cover-title {
  overflow-wrap: anywhere;
}