/* =========================================
   Reader Viewport & Layout
   ========================================= */

/* Ensure the reader takes full height and locks body scroll */
body {
  overflow: hidden; /* Disable browser scrollbar, handle in .reader-canvas-area */
}
html {
  overflow-x: hidden;
}

.guest-preview-banner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 12px 16px;
  border: 1px dashed var(--primary-200, #bfdbfe);
  background: #f8fbff;
  color: var(--text-color, #0f172a);
  border-radius: 10px;
  margin: 12px var(--space-lg, 20px) 0;
}
.guest-preview-actions {
  display: flex;
  align-items: center;
  gap: 10px;
}
.guest-countdown {
  font-variant-numeric: tabular-nums;
  font-weight: 700;
  color: var(--primary-600, #2563eb);
  padding: 6px 10px;
  background: #e8f0ff;
  border-radius: 8px;
}

.reader-viewport,
.reader-canvas-area {
  touch-action: pan-y;
}

.reader-viewport {
  width: 100%;
  overflow-x: hidden;
}

.reader-viewport {
  position: absolute;
  top: var(--header-height, 56px); /* Adjust based on your base.html header */
  left: 0;
  right: 0;
  bottom: 0;
  background-color: #e5e7eb; /* Neutral gray background for contrast */
  display: flex;
  flex-direction: column;
  z-index: 50;
}

/* PWA bottom nav should not cover the reader */
html.pwa-mobile .reader-viewport {
  bottom: calc(var(--pwa-bottom-nav-height) + var(--safe-bottom));
}

html.pwa-mobile .back-to-top {
  bottom: calc(var(--pwa-bottom-nav-height) + var(--safe-bottom) + 16px);
}

.tts-fab {
  position: fixed;
  left: 20px;
  bottom: 24px;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  border: none;
  background: linear-gradient(135deg, #0f172a, #111827);
  color: #fff;
  box-shadow: 0 8px 20px rgba(0,0,0,0.2);
  cursor: pointer;
  display: grid;
  place-items: center;
  z-index: 1200;
  opacity: 0.95;
  transition: opacity 0.2s ease, transform 0.2s ease;
}
.tts-fab:hover {
  opacity: 1;
  transform: translateY(-2px);
}
.tts-fab:focus-visible {
  outline: 2px solid #38bdf8;
  outline-offset: 2px;
}

html.pwa-mobile .tts-fab {
  bottom: calc(var(--pwa-bottom-nav-height) + var(--safe-bottom) + 16px);
}

.tts-caption {
  position: fixed;
  left: 50%;
  bottom: 24px;
  transform: translateX(-50%);
  max-width: min(92vw, 640px);
  padding: 10px 12px;
  border-radius: 999px;
  background: rgba(15, 23, 42, 0.92);
  color: #fff;
  box-shadow: 0 10px 30px rgba(15, 23, 42, 0.25);
  z-index: 1200;
  font-weight: 700;
  font-size: 0.95rem;
  line-height: 1.1;
  text-align: center;
  pointer-events: none;
}

html.pwa-mobile .tts-caption {
  bottom: calc(var(--pwa-bottom-nav-height) + var(--safe-bottom) + 16px);
}

.back-to-top {
  position: fixed;
  right: 20px;
  bottom: 24px;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  border: none;
  background: linear-gradient(135deg, #0ea5e9, #38bdf8);
  color: #fff;
  box-shadow: 0 8px 20px rgba(0,0,0,0.2);
  cursor: pointer;
  display: grid;
  place-items: center;
  z-index: 1200;
  opacity: 0.9;
  transition: opacity 0.2s ease, transform 0.2s ease;
}

.back-to-top:hover {
  opacity: 1;
  transform: translateY(-2px);
}

.back-to-top:focus-visible {
  outline: 2px solid #38bdf8;
  outline-offset: 2px;
}

/* --- Reader Header / Toolbar --- */
.reader-header {
  position: relative;
  min-height: 56px;
  background: var(--neutral-50, #ffffff);
  border-bottom: 1px solid var(--border-color, #e2e8f0);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 var(--space-lg, 20px);
  box-shadow: 0 1px 3px rgba(0,0,0,0.05);
  flex-shrink: 0; /* Prevent shrinking */
  z-index: 100;
}

.header-start {
  display: flex;
  align-items: center;
  gap: 16px;
  min-width: 0; /* Flexbox text truncation fix */
}

.header-end {
  margin-left: auto;
  display: flex;
  align-items: center;
  gap: 12px;
}

.btn-icon-back {
  width: 36px;
  height: 36px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  color: var(--text-secondary, #64748b);
  transition: background 0.2s;
}

.btn-icon-back:hover {
  background: var(--bg-secondary, #f1f5f9);
  color: var(--primary-color, #1a2f4e);
}

.book-meta {
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

.book-title {
  font-size: 1rem;
  font-weight: 700;
  margin: 0;
  color: var(--text-color, #0f172a);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

/* Keep title compact on all sizes (avoid tall headers from long titles). */

.book-author {
  font-size: 0.8rem;
  color: var(--text-secondary, #64748b);
}

/* --- Controls --- */
.reader-controls {
  display: flex;
  align-items: center;
  gap: 8px;
  background: linear-gradient(135deg, #0f172a, #111827);
  color: #e5e7eb;
  padding: 4px 8px;
  border-radius: 9px;
  border: 1px solid rgba(255, 255, 255, 0.08);
  box-shadow: 0 6px 16px rgba(0, 0, 0, 0.12);
  transition: transform 0.2s ease, opacity 0.2s ease;
}

.control-btn {
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.15);
  width: 30px;
  height: 30px;
  border-radius: 7px;
  color: #e5e7eb;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background 0.2s, transform 0.1s;
}

.control-btn:hover {
  background: rgba(255, 255, 255, 0.16);
}

.control-btn:active {
  transform: translateY(1px);
}

.tts-btn {
  background: linear-gradient(135deg, #0f172a, #111827);
  border: 1px solid rgba(15, 23, 42, 0.25);
  color: #e5e7eb;
  box-shadow: 0 6px 16px rgba(15, 23, 42, 0.16);
}

.tts-btn:hover {
  background: linear-gradient(135deg, #111827, #0b1220);
}

.zoom-display, .page-display {
  font-size: 0.82rem;
  font-weight: 600;
  font-variant-numeric: tabular-nums;
  color: #e2e8f0;
  min-width: 44px;
  text-align: center;
  user-select: none;
}

.page-display {
  min-width: 56px;
}

.divider-vertical {
  width: 1px;
  height: 20px;
  background: var(--border-color, #cbd5e1);
  margin: 0 4px;
}

.zoom-group, .page-group {
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

.page-group {
  padding: 4px 8px;
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.08);
}

.toolbar-toggle {
  display: none;
  width: 34px;
  height: 34px;
  border-radius: 8px;
  border: 1px solid var(--border-color, #e2e8f0);
  background: #fff;
  color: var(--text-color, #334155);
  align-items: center;
  justify-content: center;
  margin-right: 8px;
  cursor: pointer;
  box-shadow: 0 2px 6px rgba(0, 0, 0, 0.08);
}

/* --- Scrollable Area --- */
.reader-canvas-area {
  flex: 1;
  overflow-y: auto;
  overflow-x: hidden;
  position: relative;
  padding: 24px 0;
  scroll-behavior: smooth;
  /* Centering logic */
  display: flex;
  justify-content: center;
  align-items: flex-start;
  -webkit-overflow-scrolling: touch;
  overscroll-behavior-x: none;
  touch-action: pan-y;
}
.reader-canvas-area.pdf-mode {
  overflow-x: auto;
}
.reader-canvas-area.html-mode {
  overflow-x: hidden;
}

.pdf-wrapper {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 24px; /* Space between pages */
  width: min(100%, 1100px);
  max-width: 1100px;
  margin: 0 auto;
}

.page-stack {
  width: 100%;
  max-width: 1100px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  align-items: center;
}

/* --- Pages --- */
.pdf-page {
  background: #fff;
  box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  position: relative;
  min-height: 200px;
  transition: box-shadow 0.3s;
  margin: 0 auto;
}

.pdf-page.is-active {
  box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
  outline: 2px solid var(--primary-200, #93c5fd);
}

.pdf-page canvas {
  display: block;
  margin: 0 auto;
}

.epub-wrapper {
  position: relative;
  width: 100%;
  max-width: 1080px;
  margin: 0 auto;
  background: #fff;
  border: 1px solid var(--border-color, #e2e8f0);
  border-radius: 10px;
  box-shadow: 0 10px 30px rgba(0,0,0,0.08);
  padding: clamp(12px, 2vw, 24px) clamp(10px, 2vw, 20px) clamp(20px, 2vw, 32px);
  max-width: min(100vw, 1080px);
}

.epub-container {
  min-height: 90svh;
  height: 94svh;
  max-height: 94svh;
  width: 100%;
  border: 1px solid var(--border-color, #e2e8f0);
  border-radius: 8px;
  overflow: hidden;
  overflow-x: hidden;
  overflow-y: auto;
  display: block;
  max-width: 100%;
  width: 100%;
  box-sizing: border-box;
  overscroll-behavior-x: none;
  touch-action: pan-y;
}

.epub-download {
  display: flex;
  justify-content: flex-end;
  margin-top: 14px;
}

.reader-controls.is-html {
  opacity: 0;
  pointer-events: none;
  height: 0;
  overflow: hidden;
}

@media (max-width: 1024px) {
  .epub-wrapper {
    width: 100%;
    max-width: none;
    padding: 16px 12px 24px;
  }
}

@media (max-width: 640px) {
  body {
    overflow-y: hidden;
    overscroll-behavior-y: none;
  }
  .epub-wrapper {
    padding: 12px 8px 18px;
  }
  .epub-container {
    min-height: 82svh;
    height: 82svh;
    max-height: 92svh;
    overflow-x: hidden;
    overflow-y: auto;
    -webkit-overflow-scrolling: touch;
  }
}

@media (max-width: 640px) {
  body {
    overflow-y: auto;
    overscroll-behavior-y: contain;
    touch-action: pan-y;
  }
  .reader-viewport {
    height: 100svh;
    touch-action: pan-y;
  }
  .reader-canvas-area {
    padding: 16px 0 20px;
    touch-action: pan-y;
  }
}

/* --- Loading States --- */
.reader-loading {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  text-align: center;
  color: var(--text-secondary, #64748b);
}

.spinner-ring {
  display: inline-block;
  width: 32px;
  height: 32px;
  border: 3px solid rgba(0,0,0,0.1);
  border-radius: 50%;
  border-top-color: var(--primary-color, #2563eb);
  animation: spin 1s ease-in-out infinite;
  margin-bottom: 12px;
}

.pdf-page-error {
  display: flex;
  align-items: center;
  justify-content: center;
  background: #fef2f2;
  color: #ef4444;
  font-size: 0.9rem;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

/* --- Mobile Responsiveness --- */
@media (max-width: 640px) {
  .reader-viewport {
    top: 0; /* Fullscreen on mobile, cover standard header */
    z-index: 1000;
  }
  
  .reader-header {
    height: auto;
    flex-wrap: wrap;
    padding: 10px;
    gap: 10px;
  }

  .header-start {
    width: 100%;
    padding-right: 0;
  }

  .header-end {
    position: absolute;
    right: 10px;
    top: 8px;
    display: flex;
    justify-content: flex-end;
    align-items: flex-start;
    gap: 6px;
    transform: scale(0.9);
    transform-origin: top right;
  }

  .toolbar-toggle {
    display: inline-flex;
    position: relative;
    z-index: 2;
  }

  .reader-controls {
    position: absolute;
    right: 76px; /* sit left of toggle + audio button */
    top: 0;
    padding: 4px 6px;
    gap: 6px;
    transform: translateX(115%);
    opacity: 0;
    pointer-events: none;
    transform-origin: center right;
  }

  .reader-controls.is-open {
    transform: translateX(0);
    opacity: 1;
    pointer-events: auto;
  }
  
  .pdf-wrapper {
    gap: 12px;
  }
}