/* ============================================================
   BookReader — CSS Design System & Styles
   Dark theme, Inter font, cohesive aesthetic
   ============================================================ */

/* ---- CSS Custom Properties ---- */
:root {
  --bg: #050816;
  --bg-alt: #080b18;
  --panel: #111827;
  --panel-hover: #1a2332;
  --sidebar: #080d22;
  --sidebar-hover: #111b33;
  --primary: #5865f2;
  --primary-hover: #4752c4;
  --primary-glow: rgba(88, 101, 242, 0.15);
  --text: #ffffff;
  --text-secondary: #e0e0e0;
  --muted: #9ca3af;
  --muted-dark: #6b7280;
  --border: #1f2937;
  --border-light: #2d3748;
  --danger: #ef4444;
  --danger-hover: #dc2626;
  --success: #22c55e;
  --warning: #f59e0b;
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.3);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 8px 30px rgba(0, 0, 0, 0.5);
  --shadow-xl: 0 20px 60px rgba(0, 0, 0, 0.6);
  --radius-sm: 4px;
  --radius: 8px;
  --radius-lg: 12px;
  --radius-xl: 20px;
  --radius-full: 9999px;
  --transition-fast: 0.15s ease;
  --transition: 0.2s ease;
  --transition-slow: 0.35s cubic-bezier(0.4, 0, 0.2, 1);
  --font-sans: 'Inter', system-ui, -apple-system, 'Segoe UI', sans-serif;
}

/* ---- Reset & Base ---- */
*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-sans);
  background: var(--bg);
  color: var(--text);
  line-height: 1.5;
  overflow: hidden;
  height: 100vh;
  /* Subtle grain texture overlay */
  background-image:
    radial-gradient(ellipse at 20% 50%, rgba(88, 101, 242, 0.03) 0%, transparent 50%),
    radial-gradient(ellipse at 80% 20%, rgba(88, 101, 242, 0.04) 0%, transparent 50%);
}

a { color: inherit; text-decoration: none; }
button { cursor: pointer; font-family: inherit; border: none; background: none; color: inherit; font-size: inherit; }
input, select, textarea { font-family: inherit; font-size: inherit; }
img { display: block; max-width: 100%; }

/* Scrollbar styling */
::-webkit-scrollbar { width: 6px; height: 6px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: var(--border-light); border-radius: var(--radius-full); }
::-webkit-scrollbar-thumb:hover { background: var(--muted-dark); }

/* ---- App Layout ---- */
.app {
  display: flex;
  height: 100vh;
  overflow: hidden;
}

/* ---- Sidebar ---- */
.sidebar {
  width: 240px;
  min-width: 240px;
  height: 100vh;
  background: var(--sidebar);
  display: flex;
  flex-direction: column;
  position: relative;
  z-index: 100;
  border-right: 1px solid var(--border);
  transition: transform var(--transition-slow), min-width var(--transition-slow), width var(--transition-slow);
}

.sidebar-inner {
  flex: 1;
  padding: 20px 12px 12px;
  display: flex;
  flex-direction: column;
  overflow-y: auto;
}

.sidebar-toggle {
  display: none;
  position: absolute;
  top: 12px;
  right: -48px;
  width: 40px;
  height: 40px;
  border-radius: var(--radius);
  background: var(--sidebar);
  border: 1px solid var(--border);
  align-items: center;
  justify-content: center;
  z-index: 101;
  color: var(--muted);
  transition: color var(--transition-fast);
}
.sidebar-toggle:hover { color: var(--text); }

/* Logo */
.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 4px 8px 20px;
  margin-bottom: 8px;
}

.logo-icon {
  width: 32px;
  height: 32px;
  flex-shrink: 0;
}

.logo-text {
  font-size: 18px;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--text);
}

/* Sidebar Navigation */
.sidebar-nav {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.nav-item {
  display: flex;
  align-items: center;
  gap: 14px;
  height: 48px;
  padding: 0 14px;
  border-radius: var(--radius) 0 0 var(--radius);
  font-size: 15px;
  font-weight: 400;
  color: var(--muted);
  transition: all var(--transition);
  position: relative;
  cursor: pointer;
}

.nav-item:hover {
  color: var(--text);
  background: var(--sidebar-hover);
}

.nav-item.active {
  color: var(--text);
  background: #1d2650;
  font-weight: 500;
}

.nav-item.active::after {
  content: '';
  position: absolute;
  right: 0;
  top: 50%;
  transform: translateY(-50%);
  width: 3px;
  height: 20px;
  border-radius: 2px 0 0 2px;
  background: var(--primary);
}

.nav-icon {
  width: 20px;
  height: 20px;
  flex-shrink: 0;
  opacity: 0.8;
}

.nav-item.active .nav-icon { opacity: 1; }

/* Sidebar Footer */
.sidebar-footer {
  padding: 12px;
  border-top: 1px solid var(--border);
}

.login-btn {
  width: 100%;
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 14px;
  border-radius: var(--radius);
  font-size: 13px;
  font-weight: 500;
  color: var(--muted);
  background: var(--panel);
  transition: all var(--transition-fast);
}

.login-btn:hover {
  color: var(--text);
  background: var(--panel-hover);
}

.login-btn.logged-in {
  color: var(--success);
  background: rgba(34, 197, 94, 0.1);
}
.login-btn.logged-in:hover { background: rgba(34, 197, 94, 0.15); }

/* ---- Main Content ---- */
.main {
  flex: 1;
  display: flex;
  flex-direction: column;
  overflow: hidden;
  min-width: 0;
}

/* ---- Header ---- */
.header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
  padding: 0 28px;
  flex-shrink: 0;
  background: var(--bg);
  border-bottom: 1px solid var(--border);
}

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

.header-title {
  font-size: 22px;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--text);
}

.header-badge {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 32px;
  height: 24px;
  padding: 0 8px;
  border-radius: var(--radius-full);
  background: var(--primary);
  color: var(--text);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.02em;
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 4px;
}

.icon-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border-radius: var(--radius);
  color: var(--muted);
  background: transparent;
  transition: all var(--transition-fast);
}

.icon-btn:hover {
  color: var(--text);
  background: var(--panel);
}

/* ---- Tab Bar ---- */
.tab-bar-wrapper {
  display: flex;
  align-items: center;
  padding: 0 20px;
  gap: 6px;
  flex-shrink: 0;
  background: var(--bg);
  border-bottom: 1px solid var(--border);
}

.tab-bar {
  display: flex;
  align-items: center;
  gap: 4px;
  overflow-x: auto;
  flex: 1;
  padding: 8px 0;
  scrollbar-width: none;
}

.tab-bar::-webkit-scrollbar { display: none; }

.tab-item {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 8px 18px;
  border-radius: var(--radius-xl);
  font-size: 14px;
  font-weight: 500;
  color: var(--muted);
  white-space: nowrap;
  cursor: pointer;
  user-select: none;
  transition: all var(--transition);
  position: relative;
  border: 1px solid transparent;
  flex-shrink: 0;
}

.tab-item:hover {
  color: var(--text);
  background: var(--panel);
}

.tab-item.active {
  color: var(--text);
  background: var(--panel);
  border-color: transparent;
}

.tab-item.active::after {
  content: '';
  position: absolute;
  bottom: -9px;
  left: 20%;
  right: 20%;
  height: 2px;
  border-radius: 1px;
  background: var(--primary);
}

.tab-item.editing {
  background: var(--panel);
  border-color: var(--primary);
  box-shadow: 0 0 0 2px var(--primary-glow);
}

.tab-name-input {
  background: transparent;
  border: none;
  outline: none;
  color: var(--text);
  font-size: 14px;
  font-weight: 500;
  font-family: var(--font-sans);
  width: 80px;
  padding: 0;
}

.tab-count {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 20px;
  height: 18px;
  padding: 0 6px;
  border-radius: var(--radius-full);
  background: rgba(255, 255, 255, 0.08);
  color: var(--muted);
  font-size: 11px;
  font-weight: 600;
}

.tab-item.active .tab-count {
  background: rgba(88, 101, 242, 0.2);
  color: var(--primary);
}

.tab-add-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: var(--radius);
  color: var(--muted);
  background: transparent;
  flex-shrink: 0;
  transition: all var(--transition-fast);
}

.tab-add-btn:hover {
  color: var(--text);
  background: var(--panel);
}

/* ---- Books Container ---- */
.books-container {
  flex: 1;
  overflow-y: auto;
  overflow-x: hidden;
  padding: 24px 28px;
  scroll-behavior: smooth;
}

.books-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 24px;
}

/* ---- Book Card ---- */
.book-card {
  cursor: pointer;
  user-select: none;
  transition: transform var(--transition-slow);
}

.book-card:hover {
  transform: translateY(-4px);
}

.book-card:active {
  transform: translateY(-2px);
}

.cover-wrapper {
  position: relative;
  aspect-ratio: 3 / 4;
  overflow: hidden;
  border-radius: var(--radius-sm);
  background: var(--panel);
  box-shadow: var(--shadow-md);
  transition: box-shadow var(--transition-slow);
}

.book-card:hover .cover-wrapper {
  box-shadow: var(--shadow-lg), 0 0 20px var(--primary-glow);
}

.cover-img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform var(--transition-slow);
}

.book-card:hover .cover-img {
  transform: scale(1.05);
}

/* Cover overlay gradient for badges readability */
.cover-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(
    180deg,
    rgba(0, 0, 0, 0.4) 0%,
    transparent 40%,
    transparent 60%,
    rgba(0, 0, 0, 0.5) 100%
  );
  pointer-events: none;
}

/* Unread pages badge — top-left */
.cover-badge {
  position: absolute;
  top: 8px;
  left: 8px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 32px;
  height: 22px;
  padding: 0 8px;
  border-radius: var(--radius-sm);
  background: var(--primary);
  color: var(--text);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.03em;
  z-index: 2;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.5);
}

.cover-badge.finished {
  background: var(--success);
}

/* Options button — top-right */
.cover-options-btn {
  position: absolute;
  top: 8px;
  right: 8px;
  width: 28px;
  height: 28px;
  border-radius: var(--radius-sm);
  background: rgba(0, 0, 0, 0.5);
  backdrop-filter: blur(4px);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text);
  opacity: 0;
  transform: translateY(-4px);
  transition: all var(--transition);
  z-index: 2;
}

.book-card:hover .cover-options-btn {
  opacity: 1;
  transform: translateY(0);
}

.cover-options-btn:hover {
  background: rgba(0, 0, 0, 0.75);
  color: var(--primary);
}

/* Read/Play button — bottom-right */
.cover-read-btn {
  position: absolute;
  bottom: 10px;
  right: 10px;
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: var(--primary);
  color: var(--text);
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 4px 12px rgba(88, 101, 242, 0.4);
  opacity: 0;
  transform: translateY(8px);
  transition: all var(--transition);
  z-index: 2;
}

.book-card:hover .cover-read-btn {
  opacity: 1;
  transform: translateY(0);
}

.cover-read-btn:hover {
  background: var(--primary-hover);
  transform: translateY(0) scale(1.1) !important;
  box-shadow: 0 4px 16px rgba(88, 101, 242, 0.6);
}

/* Book title */
.book-title {
  margin-top: 10px;
  font-size: 13px;
  font-weight: 500;
  color: var(--text);
  line-height: 1.4;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
  text-overflow: ellipsis;
  transition: color var(--transition-fast);
}

.book-card:hover .book-title {
  color: var(--text-secondary);
}

.book-author {
  font-size: 11px;
  color: var(--muted);
  margin-top: 2px;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

/* ---- Book Card Actions (Local/Online Read) ---- */
.book-actions {
  display: flex;
  gap: 6px;
  margin-top: 8px;
}

.btn-local-read,
.btn-online-read {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 4px 10px;
  border-radius: 6px;
  font-size: 12px;
  font-weight: 500;
  border: 1px solid var(--border);
  background: var(--panel);
  color: var(--text-secondary);
  cursor: pointer;
  transition: all 0.2s ease;
  text-decoration: none;
  white-space: nowrap;
}

.btn-local-read:hover {
  border-color: var(--primary);
  color: var(--primary);
  background: rgba(88, 101, 242, 0.1);
}

.btn-local-read.disabled {
  opacity: 0.5;
  cursor: not-allowed;
  pointer-events: none;
  border-color: var(--muted-dark);
  color: var(--muted);
  background: transparent;
}

.btn-online-read:hover {
  border-color: var(--accent);
  color: var(--accent);
  background: rgba(231, 199, 133, 0.08);
}

/* ---- Empty & Loading States ---- */
.empty-state, .loading-state {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  min-height: 300px;
  gap: 12px;
  color: var(--muted);
  text-align: center;
}

.empty-state p:first-of-type {
  font-size: 16px;
  font-weight: 500;
  color: var(--text-secondary);
}

.empty-state-kaomoji {
  font-size: 28px;
  color: var(--muted);
  opacity: 0.6;
  margin-bottom: 4px;
  letter-spacing: 2px;
}

.text-muted { color: var(--muted); font-size: 13px; }

/* Spinner */
.spinner {
  width: 32px;
  height: 32px;
  border: 3px solid var(--border-light);
  border-top-color: var(--primary);
  border-radius: 50%;
  animation: spin 0.6s linear infinite;
}

.spinner-sm {
  width: 16px;
  height: 16px;
  border-width: 2px;
  display: inline-block;
}

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

/* ---- Custom Context Menu ---- */
.context-menu {
  position: fixed;
  z-index: 1000;
  min-width: 200px;
  background: var(--panel);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-xl);
  padding: 6px;
  opacity: 0;
  transform: scale(0.95);
  transition: opacity var(--transition-fast), transform var(--transition-fast);
  pointer-events: none;
  backdrop-filter: blur(12px);
}

.context-menu.visible {
  opacity: 1;
  transform: scale(1);
  pointer-events: all;
}

.context-menu-item {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 14px;
  border-radius: var(--radius-sm);
  font-size: 13px;
  font-weight: 400;
  color: var(--text-secondary);
  cursor: pointer;
  transition: all var(--transition-fast);
  position: relative;
  white-space: nowrap;
  min-width: 180px;
}

.context-menu-item:hover {
  background: var(--sidebar-hover);
  color: var(--text);
}

.context-menu-item.danger {
  color: var(--danger);
}
.context-menu-item.danger:hover {
  background: rgba(239, 68, 68, 0.1);
  color: var(--danger);
}

.context-menu-divider {
  height: 1px;
  margin: 4px 8px;
  background: var(--border);
}

.context-menu-icon {
  width: 16px;
  height: 16px;
  opacity: 0.7;
  flex-shrink: 0;
}

.context-menu-sub-arrow {
  margin-left: auto;
  opacity: 0.4;
  font-size: 10px;
}

/* Context sub-menu */
.context-submenu {
  position: absolute;
  left: 100%;
  top: -6px;
  min-width: 180px;
  background: var(--panel);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-xl);
  padding: 6px;
  display: none;
  z-index: 1001;
}

.context-menu-item:hover > .context-submenu {
  display: block;
}

/* ---- Modals ---- */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.7);
  backdrop-filter: blur(4px);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 500;
  animation: fadeIn 0.2s ease;
}

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

.modal {
  background: var(--panel);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-xl);
  width: 90%;
  max-width: 560px;
  max-height: 85vh;
  display: flex;
  flex-direction: column;
  animation: modalSlideIn 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

@keyframes modalSlideIn {
  from { opacity: 0; transform: translateY(20px) scale(0.97); }
  to { opacity: 1; transform: translateY(0) scale(1); }
}

.modal-sm { max-width: 380px; }

.search-modal { max-width: 680px; }

.modal-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 20px 24px 0;
}

.modal-header h2 {
  font-size: 18px;
  font-weight: 600;
  letter-spacing: -0.01em;
}

.modal-close {
  width: 32px;
  height: 32px;
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--muted);
  transition: all var(--transition-fast);
}

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

.modal-body {
  padding: 20px 24px 24px;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

/* ---- Form Elements ---- */
.form-group {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.form-group label {
  font-size: 13px;
  font-weight: 500;
  color: var(--muted);
  letter-spacing: 0.01em;
}

.form-input {
  width: 100%;
  padding: 10px 14px;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--text);
  font-size: 14px;
  outline: none;
  transition: border-color var(--transition-fast);
}

.form-input:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px var(--primary-glow);
}

.form-input::placeholder { color: var(--muted-dark); }

select.form-input { cursor: pointer; }

/* ---- Buttons ---- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  padding: 10px 20px;
  border-radius: var(--radius);
  font-size: 14px;
  font-weight: 500;
  letter-spacing: 0.01em;
  border: none;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.btn-primary {
  background: var(--primary);
  color: var(--text);
}

.btn-primary:hover {
  background: var(--primary-hover);
  box-shadow: 0 4px 12px var(--primary-glow);
}

.btn-danger {
  background: var(--danger);
  color: var(--text);
}
.btn-danger:hover { background: var(--danger-hover); }

.btn-block { width: 100%; }

/* ---- Search ---- */
.search-input-group {
  display: flex;
  gap: 10px;
}

.search-input {
  flex: 1;
  padding: 10px 16px;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--text);
  font-size: 15px;
  outline: none;
  transition: border-color var(--transition-fast);
}

.search-input:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px var(--primary-glow);
}

.search-input::placeholder { color: var(--muted-dark); }

.search-filters {
  background: var(--bg);
  border-radius: var(--radius);
  border: 1px solid var(--border);
}

.filter-group { padding: 0; }

.filter-group summary {
  padding: 10px 14px;
  font-size: 13px;
  font-weight: 500;
  color: var(--muted);
  cursor: pointer;
  user-select: none;
}

.filter-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
  gap: 12px;
  padding: 8px 14px 14px;
}

.filter-field {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.filter-field label {
  font-size: 11px;
  font-weight: 500;
  color: var(--muted-dark);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.filter-field input,
.filter-field select {
  padding: 8px 10px;
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--text);
  font-size: 13px;
  outline: none;
}

.filter-field input:focus,
.filter-field select:focus {
  border-color: var(--primary);
}

/* Search results */
.search-results {
  display: flex;
  flex-direction: column;
  gap: 8px;
  max-height: 400px;
  overflow-y: auto;
}

.search-empty {
  text-align: center;
  padding: 40px;
  color: var(--muted);
  font-size: 14px;
}

.search-loading {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  padding: 40px;
  color: var(--muted);
}

.search-result-item {
  display: flex;
  gap: 14px;
  padding: 12px;
  background: var(--bg);
  border-radius: var(--radius);
  border: 1px solid var(--border);
  transition: all var(--transition-fast);
  align-items: flex-start;
}

.search-result-item:hover {
  border-color: var(--border-light);
  background: var(--panel-hover);
}

.search-result-cover {
  width: 60px;
  height: 80px;
  border-radius: var(--radius-sm);
  object-fit: cover;
  flex-shrink: 0;
  background: var(--panel);
}

.search-result-info {
  flex: 1;
  min-width: 0;
}

.search-result-title {
  font-size: 14px;
  font-weight: 500;
  color: var(--text);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.search-result-author {
  font-size: 12px;
  color: var(--muted);
  margin-top: 2px;
}

.search-result-meta {
  display: flex;
  gap: 8px;
  margin-top: 4px;
  font-size: 11px;
  color: var(--muted-dark);
}

.search-result-add {
  margin-top: 8px;
  display: flex;
  gap: 6px;
  align-items: center;
}

.search-result-add select {
  padding: 6px 10px;
  font-size: 12px;
  border-radius: var(--radius-sm);
  background: var(--panel);
  border: 1px solid var(--border);
  color: var(--text);
  outline: none;
}

.search-result-add .btn {
  padding: 6px 12px;
  font-size: 12px;
}

/* ---- Upload ---- */
.upload-dropzone {
  border: 2px dashed var(--border-light);
  border-radius: var(--radius-lg);
  padding: 40px 20px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  cursor: pointer;
  transition: all var(--transition-fast);
  text-align: center;
  color: var(--muted);
}

.upload-dropzone:hover {
  border-color: var(--primary);
  background: var(--primary-glow);
}

.upload-dropzone.drag-over {
  border-color: var(--primary);
  background: var(--primary-glow);
  transform: scale(1.01);
}

.upload-dropzone p {
  font-size: 14px;
  font-weight: 500;
}

/* ---- Login ---- */
.login-error {
  font-size: 13px;
  color: var(--danger);
  text-align: center;
}

/* ---- Toast Notifications ---- */
.toast-container {
  position: fixed;
  top: 20px;
  right: 20px;
  z-index: 2000;
  display: flex;
  flex-direction: column;
  gap: 8px;
  pointer-events: none;
}

.toast {
  padding: 12px 20px;
  border-radius: var(--radius);
  font-size: 13px;
  font-weight: 500;
  color: var(--text);
  background: var(--panel);
  border: 1px solid var(--border-light);
  box-shadow: var(--shadow-lg);
  animation: toastSlideIn 0.3s ease;
  pointer-events: all;
  max-width: 360px;
}

.toast.success { border-left: 3px solid var(--success); }
.toast.error { border-left: 3px solid var(--danger); }
.toast.info { border-left: 3px solid var(--primary); }

.toast.removing {
  animation: toastSlideOut 0.3s ease forwards;
}

@keyframes toastSlideIn {
  from { opacity: 0; transform: translateX(40px); }
  to { opacity: 1; transform: translateX(0); }
}

@keyframes toastSlideOut {
  from { opacity: 1; transform: translateX(0); }
  to { opacity: 0; transform: translateX(40px); }
}

/* ---- Drag & Drop sorting ---- */
.book-card.drag-over {
  opacity: 0.5;
}

.tab-item.drag-target {
  border-left: 2px solid var(--primary);
}

/* ---- Responsive ---- */
@media (max-width: 1024px) {
  .sidebar {
    width: 72px;
    min-width: 72px;
  }

  .logo-text,
  .nav-item span,
  .login-btn span {
    display: none;
  }

  .nav-item {
    justify-content: center;
    padding: 0;
    gap: 0;
  }

  .nav-item.active::after { display: none; }

  .logo {
    justify-content: center;
    padding: 4px 0 20px;
  }

  .login-btn {
    justify-content: center;
    padding: 10px;
  }

  .sidebar-footer { padding: 8px; }
  .sidebar-inner { padding: 20px 8px 12px; }
}

@media (max-width: 768px) {
  .sidebar {
    position: fixed;
    left: 0;
    top: 0;
    transform: translateX(-100%);
    width: 240px;
    min-width: 240px;
  }

  .sidebar.open {
    transform: translateX(0);
  }

  .sidebar-toggle { display: flex; }

  .logo-text,
  .nav-item span,
  .login-btn span { display: inline; }

  .nav-item { justify-content: flex-start; padding: 0 14px; gap: 14px; }
  .nav-item.active::after { display: block; }
  .logo { justify-content: flex-start; padding: 4px 8px 20px; }
  .login-btn { justify-content: flex-start; padding: 10px 14px; }
  .sidebar-footer { padding: 12px; }
  .sidebar-inner { padding: 20px 12px 12px; }

  .header { padding: 0 16px; }
  .header-title { font-size: 18px; }
  .books-container { padding: 16px; }
  .books-grid {
    grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
    gap: 16px;
  }
  .tab-bar-wrapper { padding: 0 8px; }

  .modal {
    width: 95%;
    max-height: 90vh;
  }
}

@media (max-width: 480px) {
  .books-grid {
    grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
    gap: 12px;
  }
  .header-actions .icon-btn:nth-child(n+3) { display: none; }
}

/* ---- Selection mode (for multi-select) ---- */
.book-card.selected .cover-wrapper {
  outline: 3px solid var(--primary);
  outline-offset: 2px;
}

.book-card.selected::after {
  content: '✓';
  position: absolute;
  top: 8px;
  right: 8px;
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: var(--primary);
  color: var(--text);
  font-size: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 10;
}

/* ---- Card skeleton for loading ---- */
.book-card.skeleton .cover-wrapper {
  background: linear-gradient(
    110deg,
    var(--panel) 30%,
    var(--panel-hover) 50%,
    var(--panel) 70%
  );
  background-size: 200% 100%;
  animation: shimmer 1.5s ease-in-out infinite;
}

.book-card.skeleton .book-title {
  height: 16px;
  background: var(--panel);
  border-radius: var(--radius-sm);
  width: 80%;
  margin-top: 10px;
}

.book-card.skeleton .book-author {
  height: 12px;
  background: var(--panel);
  border-radius: var(--radius-sm);
  width: 60%;
  margin-top: 6px;
}

@keyframes shimmer {
  0% { background-position: -200% 0; }
  100% { background-position: 200% 0; }
}

/* ============================================================
   Detail Page — Dark Theme (bg #080808, panel #211315, accent #e7c785)
   ============================================================ */

/* Header back button */
.header-back-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: var(--radius);
  color: var(--muted);
  background: transparent;
  transition: all var(--transition-fast);
  flex-shrink: 0;
  margin-right: 4px;
  border: none;
  cursor: pointer;
}
.header-back-btn:hover {
  color: var(--text);
  background: var(--panel);
}

/* Detail Page Container */
.detail-page {
  flex: 1;
  display: flex;
  flex-direction: column;
  overflow: hidden;
  position: relative;
  background: #080808;
}

.detail-content {
  flex: 1;
  display: flex;
  gap: 0;
  overflow: hidden;
  padding: 28px;
}

/* Left Panel */
.detail-left {
  width: 420px;
  min-width: 420px;
  display: flex;
  flex-direction: column;
  align-items: center;
  overflow-y: auto;
  padding-right: 28px;
  gap: 20px;
}

.detail-cover-wrapper {
  width: 300px;
  height: 420px;
  flex-shrink: 0;
  overflow: hidden;
  border-radius: 5px;
  background: #211315;
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.5);
  position: relative;
}

.detail-cover {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.detail-meta {
  width: 100%;
  text-align: center;
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.detail-title {
  font-size: 22px;
  font-weight: 700;
  color: #ffffff;
  letter-spacing: -0.01em;
  line-height: 1.3;
}

.detail-author {
  font-size: 14px;
  color: #a0a0a0;
  font-weight: 400;
}

.detail-status,
.detail-source {
  font-size: 13px;
  color: #a0a0a0;
}

/* Description */
.detail-desc {
  width: 100%;
  background: #211315;
  border-radius: 8px;
  padding: 14px 16px;
  position: relative;
}

.detail-desc-text {
  font-size: 13px;
  color: #a0a0a0;
  line-height: 1.7;
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
  text-overflow: ellipsis;
  transition: -webkit-line-clamp var(--transition-slow);
}

.detail-desc-text.expanded {
  -webkit-line-clamp: unset;
}

.detail-desc-more {
  display: inline-block;
  font-size: 13px;
  color: #e7c785;
  cursor: pointer;
  background: none;
  border: none;
  padding: 0;
  margin-top: 6px;
  font-family: var(--font-sans);
  transition: color var(--transition-fast);
}

.detail-desc-more:hover {
  color: #f0d690;
}

/* Tags */
.detail-tags {
  width: 100%;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  justify-content: center;
}

.detail-tag {
  display: inline-flex;
  align-items: center;
  padding: 5px 12px;
  border-radius: 20px;
  border: 1px solid #555;
  font-size: 12px;
  color: #a0a0a0;
  background: transparent;
  transition: all var(--transition-fast);
}

.detail-tag:hover {
  border-color: #e7c785;
  color: #e7c785;
}

/* Action Buttons */
.detail-actions {
  width: 100%;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.detail-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  padding: 10px 16px;
  border-radius: 8px;
  font-size: 13px;
  font-weight: 500;
  color: #a0a0a0;
  background: transparent;
  border: 1px solid #333;
  cursor: pointer;
  transition: all var(--transition-fast);
  flex: 1 1 auto;
  min-width: 0;
  white-space: nowrap;
}

.detail-btn:hover {
  color: #ffffff;
  border-color: #555;
  background: rgba(255,255,255,0.04);
}

.detail-btn-primary {
  background: #e7c785;
  color: #000;
  border-color: #e7c785;
  flex: 2 1 auto;
}

.detail-btn-primary:hover {
  background: #f0d690;
  border-color: #f0d690;
  color: #000;
  box-shadow: 0 4px 16px rgba(231, 199, 133, 0.3);
}

/* Right Panel: TOC */
.detail-right {
  flex: 1;
  display: flex;
  flex-direction: column;
  overflow: hidden;
  background: #211315;
  border-radius: 12px;
  padding: 24px;
  min-width: 0;
}

.toc-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-shrink: 0;
  margin-bottom: 16px;
  padding-bottom: 16px;
  border-bottom: 1px solid #2a1c1f;
}

.toc-title {
  font-size: 18px;
  font-weight: 600;
  color: #ffffff;
  letter-spacing: -0.01em;
  white-space: nowrap;
}

.toc-count {
  font-weight: 400;
  color: #a0a0a0;
  font-size: 15px;
}

.toc-header-actions {
  display: flex;
  align-items: center;
  gap: 8px;
}

.toc-search-wrapper {
  position: relative;
  display: flex;
  align-items: center;
}

.toc-search-icon {
  position: absolute;
  left: 10px;
  color: #555;
  pointer-events: none;
}

.toc-search {
  width: 180px;
  padding: 8px 12px 8px 32px;
  background: #1a0e11;
  border: 1px solid #2a1c1f;
  border-radius: 8px;
  color: #ffffff;
  font-size: 13px;
  outline: none;
  font-family: var(--font-sans);
  transition: border-color var(--transition-fast);
}

.toc-search::placeholder { color: #555; }

.toc-search:focus {
  border-color: #e7c785;
}

.toc-sort-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 34px;
  height: 34px;
  border-radius: 8px;
  color: #a0a0a0;
  background: transparent;
  border: none;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.toc-sort-btn:hover {
  color: #ffffff;
  background: #332022;
}

.toc-list {
  flex: 1;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.toc-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 70px;
  padding: 12px 16px;
  background: #241618;
  border-radius: 6px;
  cursor: pointer;
  transition: background var(--transition-fast);
  gap: 12px;
}

.toc-item:hover {
  background: #332022;
}

.toc-item-info {
  flex: 1;
  min-width: 0;
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.toc-item-title {
  font-size: 14px;
  font-weight: 500;
  color: #ffffff;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.toc-item-date {
  font-size: 12px;
  color: #a0a0a0;
}

.toc-item-progress {
  height: 4px;
  border-radius: 2px;
  background: #332022;
  margin-top: 4px;
  overflow: hidden;
}

.toc-item-progress-bar {
  height: 100%;
  border-radius: 2px;
  background: #e7c785;
  transition: width var(--transition-fast);
}

.toc-item-options {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 30px;
  height: 30px;
  border-radius: 6px;
  color: #a0a0a0;
  background: transparent;
  border: none;
  cursor: pointer;
  flex-shrink: 0;
  transition: all var(--transition-fast);
}

.toc-item-options:hover {
  color: #ffffff;
  background: rgba(255,255,255,0.08);
}

.toc-empty {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  min-height: 200px;
  color: #a0a0a0;
  font-size: 14px;
  gap: 8px;
}

/* Continue Reading FAB */
.continue-reading-btn {
  position: fixed;
  bottom: 30px;
  right: 40px;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 25px;
  border-radius: 30px;
  background: #e7c785;
  color: #000;
  font-size: 14px;
  font-weight: 600;
  border: none;
  cursor: pointer;
  z-index: 200;
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.5), 0 0 0 1px rgba(231, 199, 133, 0.3);
  transition: all var(--transition);
  animation: fabSlideUp 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

.continue-reading-btn:hover {
  background: #f0d690;
  transform: translateY(-2px);
  box-shadow: 0 12px 32px rgba(0, 0, 0, 0.6), 0 0 0 2px rgba(231, 199, 133, 0.5);
}

.continue-reading-btn:active {
  transform: translateY(0);
}

@keyframes fabSlideUp {
  from { opacity: 0; transform: translateY(20px); }
  to { opacity: 1; transform: translateY(0); }
}

/* Download to Shelf Modal */
.shelf-checkbox-list {
  display: flex;
  flex-direction: column;
  gap: 8px;
  max-height: 300px;
  overflow-y: auto;
  padding: 4px 0;
}

.shelf-checkbox-item {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 14px;
  background: var(--bg);
  border-radius: var(--radius);
  border: 1px solid var(--border);
  cursor: pointer;
  transition: all var(--transition-fast);
  user-select: none;
}

.shelf-checkbox-item:hover {
  border-color: var(--border-light);
  background: var(--panel-hover);
}

.shelf-checkbox-item.selected {
  border-color: var(--primary);
  background: var(--primary-glow);
}

.shelf-checkbox {
  width: 18px;
  height: 18px;
  border-radius: 4px;
  border: 2px solid var(--muted-dark);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  transition: all var(--transition-fast);
  background: transparent;
}

.shelf-checkbox-item.selected .shelf-checkbox {
  border-color: var(--primary);
  background: var(--primary);
}

.shelf-checkbox-item.selected .shelf-checkbox::after {
  content: '';
  display: block;
  width: 5px;
  height: 8px;
  border: solid #fff;
  border-width: 0 2px 2px 0;
  transform: rotate(45deg);
  margin-top: -1px;
}

.shelf-checkbox-label {
  font-size: 14px;
  font-weight: 500;
  color: var(--text-secondary);
  flex: 1;
}

/* Page mode visibility utilities */
.tab-bar-wrapper.hidden {
  display: none;
}

/* ============================================================
   Detail Page Responsive
   ============================================================ */
@media (max-width: 1024px) {
  .detail-content {
    flex-direction: column;
    overflow-y: auto;
    padding: 20px;
  }
  .detail-left {
    width: 100%;
    min-width: 100%;
    padding-right: 0;
    flex-direction: row;
    flex-wrap: wrap;
    justify-content: center;
    gap: 16px;
  }
  .detail-cover-wrapper {
    width: 200px;
    height: 280px;
  }
  .detail-meta {
    text-align: left;
    flex: 1;
    min-width: 200px;
  }
  .detail-right {
    margin-top: 20px;
  }
  .continue-reading-btn {
    bottom: 20px;
    right: 20px;
    padding: 12px 20px;
  }
}

@media (max-width: 768px) {
  .detail-content {
    padding: 12px;
  }
  .detail-left {
    flex-direction: column;
    align-items: center;
    padding-right: 0;
  }
  .detail-cover-wrapper {
    width: 180px;
    height: 252px;
  }
  .detail-meta {
    text-align: center;
    width: 100%;
  }
  .detail-title { font-size: 18px; }
  .toc-search { width: 120px; }
  .continue-reading-btn {
    bottom: 16px;
    right: 16px;
  }
}

/* ============================================================
   Auth Page
   ============================================================ */
.auth-page {
  position: fixed;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--bg);
  z-index: 9999;
}

.auth-card {
  width: 100%;
  max-width: 400px;
  padding: 40px 36px;
  background: var(--panel);
  border-radius: 12px;
  border: 1px solid rgba(255,255,255,0.06);
}

.auth-logo {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  margin-bottom: 28px;
  font-size: 22px;
  font-weight: 700;
  color: #fff;
}

.auth-tabs {
  display: flex;
  gap: 0;
  margin-bottom: 24px;
  border-radius: 8px;
  overflow: hidden;
  border: 1px solid rgba(255,255,255,0.08);
}

.auth-tab {
  flex: 1;
  padding: 10px 0;
  text-align: center;
  font-size: 15px;
  font-weight: 500;
  color: var(--muted);
  background: transparent;
  border: none;
  cursor: pointer;
  transition: all 0.2s;
}

.auth-tab.active {
  background: var(--primary);
  color: #fff;
}

.auth-page .form-group {
  margin-bottom: 16px;
}

.auth-page .form-input {
  width: 100%;
  padding: 12px 14px;
  background: rgba(255,255,255,0.05);
  border: 1px solid rgba(255,255,255,0.1);
  border-radius: 8px;
  color: #fff;
  font-size: 14px;
  box-sizing: border-box;
}

.auth-page .form-input:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 2px rgba(88,101,242,0.2);
}

/* Sidebar user info */
.sidebar-user {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 10px 14px;
  margin-bottom: 8px;
  background: rgba(255,255,255,0.04);
  border-radius: 8px;
}

.sidebar-user-email {
  font-size: 12px;
  color: var(--muted);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  max-width: 160px;
}

.sidebar-user-logout {
  background: none;
  border: none;
  color: var(--muted);
  cursor: pointer;
  padding: 4px;
  border-radius: 4px;
  transition: all 0.2s;
  display: flex;
  align-items: center;
}

.sidebar-user-logout:hover {
  color: #ef4444;
  background: rgba(239,68,68,0.1);
}

/* Proxy settings in login modal */
.proxy-details {
  margin-top: 4px;
}

.proxy-details summary {
  font-size: 13px;
  color: var(--muted);
  cursor: pointer;
  user-select: none;
  padding: 4px 0;
}

.proxy-details summary:hover {
  color: var(--primary);
}

.proxy-row {
  display: flex;
  gap: 8px;
  margin-top: 8px;
}

.proxy-row .form-input {
  flex: 1;
}

/* ── Download Progress Cards ── */
.download-card .download-progress-section { padding: 0 14px 14px; min-height: 52px; }

.download-progress-bar-wrapper {
  height: 5px;
  background: #332022;
  border-radius: 3px;
  overflow: hidden;
  margin-bottom: 6px;
}

.download-progress-bar {
  height: 100%;
  background: #e7c785;
  border-radius: 3px;
  transition: width 0.3s ease;
  width: 0;
}
.download-progress-bar.failed { background: var(--danger); }

.download-progress-info {
  display: flex;
  justify-content: space-between;
  font-size: 12px;
  color: var(--muted);
}

.download-progress-status { color: #e7c785; font-weight: 500; }
.download-progress-status.failed { color: var(--danger); }

.download-error {
  font-size: 11px;
  color: var(--danger);
  margin-top: 4px;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

/* ============================================================
   History Page
   ============================================================ */
#historyContainer {
  max-width: 720px;
  margin: 0 auto;
  padding: 24px 20px;
}

.history-date-group {
  margin-bottom: 28px;
}

.history-date-title {
  font-size: 22px;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 16px;
}

.history-card {
  display: flex;
  align-items: center;
  height: 72px;
  width: 100%;
  background: #151827;
  border-radius: 6px;
  margin-bottom: 10px;
  cursor: pointer;
  transition: background var(--transition);
  overflow: hidden;
}
.history-card:hover {
  background: #1b2033;
}

.history-card-cover {
  width: 56px;
  height: 56px;
  border-radius: 4px;
  overflow: hidden;
  flex-shrink: 0;
  margin-left: 8px;
  background: var(--panel);
  display: flex;
  align-items: center;
  justify-content: center;
}
.history-card-cover img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}
.history-card-cover-placeholder {
  font-size: 12px;
  font-weight: 600;
  color: var(--muted);
  text-transform: uppercase;
}

.history-card-info {
  flex: 1;
  min-width: 0;
  margin-left: 12px;
  padding-right: 12px;
}

.history-card-title {
  font-size: 16px;
  color: var(--text);
  font-weight: 500;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.history-card-meta {
  font-size: 13px;
  color: #7d849b;
  margin-top: 2px;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}