/* Full-Screen PDF Reader Overlay & Viewport Styles */
#pdf-reader-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  background-color: var(--reader-light-bg);
  z-index: 1000;
  display: flex;
  flex-direction: column;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.25s ease;
}

#pdf-reader-overlay.active {
  opacity: 1;
  pointer-events: auto;
}

/* Reader Top Toolbar */
.reader-toolbar {
  height: 60px;
  background-color: #0F172A;
  color: #FFFFFF;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 1.25rem;
  z-index: 20;
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
  gap: 1rem;
}

.reader-title-area {
  display: flex;
  align-items: center;
  gap: 1rem;
  max-width: 300px;
}

.reader-back-btn {
  background: none;
  border: none;
  color: #E2E8F0;
  font-size: 1.25rem;
  cursor: pointer;
  padding: 0.4rem;
  border-radius: var(--border-radius-sm);
  display: flex;
  align-items: center;
  transition: var(--transition-fast);
}

.reader-back-btn:hover {
  background-color: rgba(255, 255, 255, 0.15);
  color: #FFF;
}

.reader-doc-title {
  font-family: var(--font-heading);
  font-weight: 600;
  font-size: 0.95rem;
  color: #F8FAFC;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.reader-controls-center {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  background-color: rgba(255, 255, 255, 0.08);
  padding: 0.25rem 0.75rem;
  border-radius: var(--border-radius-full);
}

.page-nav-btn {
  background: none;
  border: none;
  color: #CBD5E1;
  font-size: 1rem;
  cursor: pointer;
  padding: 0.25rem 0.5rem;
  border-radius: var(--border-radius-sm);
  display: flex;
  align-items: center;
}

.page-nav-btn:hover {
  color: #FFF;
  background-color: rgba(255, 255, 255, 0.15);
}

.page-num-input {
  width: 44px;
  text-align: center;
  background: rgba(0, 0, 0, 0.3);
  border: 1px solid rgba(255, 255, 255, 0.2);
  color: #FFF;
  border-radius: var(--border-radius-sm);
  padding: 0.2rem 0.3rem;
  font-size: 0.85rem;
  outline: none;
}

.page-count-text {
  font-size: 0.85rem;
  color: #94A3B8;
}

.reader-toolbar-right {
  display: flex;
  align-items: center;
  gap: 0.6rem;
}

.mode-toggle-group {
  display: flex;
  align-items: center;
  background-color: rgba(0, 0, 0, 0.3);
  border-radius: var(--border-radius-full);
  padding: 0.15rem;
  border: 1px solid rgba(255, 255, 255, 0.15);
}

.mode-btn {
  border: none;
  background: transparent;
  color: #94A3B8;
  padding: 0.3rem 0.65rem;
  border-radius: var(--border-radius-full);
  font-size: 0.78rem;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition-fast);
}

.mode-btn.active {
  background-color: var(--brand-primary);
  color: #FFF;
}

.tool-btn {
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.12);
  color: #E2E8F0;
  width: 36px;
  height: 36px;
  border-radius: var(--border-radius-full);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  font-size: 1rem;
  transition: var(--transition-fast);
}

.tool-btn:hover, .tool-btn.active {
  background-color: var(--brand-primary);
  color: #FFF;
  border-color: var(--brand-primary);
}

/* Main Reader Viewport Canvas Container */
.reader-viewport {
  flex: 1;
  display: flex;
  position: relative;
  overflow: hidden;
}

.reader-main-canvas-area {
  flex: 1;
  overflow: auto;
  padding: 2rem 1rem;
  position: relative;
  transition: background-color 0.25s ease;
  text-align: center;
}

/* Reading Theme Modes */
.reader-viewport[data-mode="light"] .reader-main-canvas-area {
  background-color: var(--reader-light-bg);
}

.reader-viewport[data-mode="dark"] .reader-main-canvas-area {
  background-color: var(--reader-dark-bg);
}

.reader-viewport[data-mode="dark"] canvas {
  filter: invert(0.92) hue-rotate(180deg) contrast(1.1);
}

.reader-viewport[data-mode="sepia"] .reader-main-canvas-area {
  background-color: var(--reader-sepia-bg);
}

.reader-viewport[data-mode="sepia"] canvas {
  filter: sepia(0.35) contrast(0.95);
}

/* Canvas Container */
.canvas-wrapper {
  display: inline-block;
  margin: 0 auto 2rem auto;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.25);
  border-radius: var(--border-radius-sm);
  background-color: #FFF;
  position: relative;
  transition: transform 0.2s ease;
}

canvas {
  display: block;
  border-radius: var(--border-radius-sm);
}

/* Reader Sidebar Drawer (Bookmarks / Search / AI) */
.reader-drawer {
  width: 320px;
  background-color: var(--bg-surface);
  border-left: 1px solid var(--border-color);
  display: flex;
  flex-direction: column;
  z-index: 15;
  transform: translateX(100%);
  transition: transform 0.3s cubic-bezier(0.16, 1, 0.3, 1);
  position: absolute;
  right: 0;
  top: 0;
  bottom: 0;
}

.reader-drawer.active {
  transform: translateX(0);
}

.drawer-header {
  padding: 1rem 1.25rem;
  border-bottom: 1px solid var(--border-color);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.drawer-title {
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 1.1rem;
  color: var(--text-primary);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.drawer-content {
  flex: 1;
  overflow-y: auto;
  padding: 1.25rem;
}

.bookmark-item {
  padding: 0.85rem;
  border-radius: var(--border-radius-md);
  border: 1px solid var(--border-color);
  background-color: var(--bg-main);
  margin-bottom: 0.75rem;
  cursor: pointer;
  transition: var(--transition-fast);
}

.bookmark-item:hover {
  border-color: var(--brand-primary);
  background-color: var(--bg-surface-elevated);
}

.bookmark-item-title {
  font-weight: 600;
  font-size: 0.9rem;
  color: var(--text-primary);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.bookmark-item-page {
  font-size: 0.78rem;
  color: var(--brand-primary);
  font-weight: 700;
}

.bookmark-item-note {
  font-size: 0.82rem;
  color: var(--text-secondary);
  margin-top: 0.3rem;
}

/* AI Assistant Drawer Panels */
.ai-panel {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

.ai-card {
  background: linear-gradient(135deg, rgba(99, 102, 241, 0.08), rgba(217, 119, 6, 0.08));
  border: 1px solid rgba(99, 102, 241, 0.2);
  border-radius: var(--border-radius-lg);
  padding: 1rem;
}

.ai-card-title {
  font-family: var(--font-heading);
  font-size: 0.92rem;
  font-weight: 700;
  color: var(--brand-accent);
  margin-bottom: 0.5rem;
  display: flex;
  align-items: center;
  gap: 0.4rem;
}

.ai-suggestion-chips {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin-top: 0.5rem;
}

.chip-action {
  padding: 0.3rem 0.65rem;
  border-radius: var(--border-radius-full);
  background-color: var(--bg-surface);
  border: 1px solid var(--border-color);
  font-size: 0.78rem;
  font-weight: 600;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 0.3rem;
}

.chip-action:hover {
  border-color: var(--brand-primary);
  color: var(--brand-primary);
}

.chat-messages {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  max-height: 240px;
  overflow-y: auto;
  padding-right: 0.25rem;
}

.chat-msg {
  padding: 0.65rem 0.85rem;
  border-radius: var(--border-radius-md);
  font-size: 0.85rem;
  line-height: 1.4;
}

.chat-msg.user {
  background-color: var(--brand-accent);
  color: #FFF;
  align-self: flex-end;
  border-bottom-right-radius: 2px;
}

.chat-msg.ai {
  background-color: var(--bg-main);
  border: 1px solid var(--border-color);
  color: var(--text-primary);
  align-self: flex-start;
  border-bottom-left-radius: 2px;
}

.chat-input-wrap {
  display: flex;
  gap: 0.5rem;
  margin-top: 0.5rem;
}

.chat-input-wrap input {
  flex: 1;
  padding: 0.5rem 0.75rem;
  border-radius: var(--border-radius-md);
  border: 1px solid var(--border-color);
  font-size: 0.85rem;
  background-color: var(--bg-main);
  color: var(--text-primary);
  outline: none;
}