:root {
  --bg-base: #0b0f19;
  --bg-surface: #111827;
  --bg-elevated: #1e293b;
  --bg-hover: #273549;
  --bg-active-seg: rgba(56, 189, 248, 0.14);
  --border-subtle: rgba(148, 163, 184, 0.16);
  --border-focus: #38bdf8;
  --text-primary: #f8fafc;
  --text-secondary: #cbd5e1;
  --text-muted: #94a3b8;
  --accent-primary: #0ea5e9;
  --accent-primary-hover: #0284c7;
  --accent-secondary: #6366f1;
  --accent-word-bg: #f59e0b;
  --accent-word-text: #0f172a;
  --success: #10b981;
  --warning: #f59e0b;
  --danger: #ef4444;
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 14px;
  --shadow-card: 0 10px 30px -10px rgba(0, 0, 0, 0.5);
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-display: 'Outfit', 'Inter', sans-serif;
}

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

body {
  font-family: var(--font-sans);
  background-color: var(--bg-base);
  color: var(--text-primary);
  line-height: 1.5;
  min-height: 100vh;
  overflow-x: hidden;
}

.hidden {
  display: none !important;
}

/* AUTH VIEW */
.auth-container {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
  background: radial-gradient(circle at top right, rgba(14, 165, 233, 0.16), transparent 50%),
              radial-gradient(circle at bottom left, rgba(99, 102, 241, 0.14), transparent 50%),
              var(--bg-base);
}

.auth-card {
  width: 100%;
  max-width: 460px;
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 32px;
  box-shadow: var(--shadow-card);
}

.brand-header {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 24px;
}

.brand-logo {
  width: 48px;
  height: 48px;
  border-radius: 12px;
  background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.25rem;
  color: #fff;
}

.brand-title {
  font-family: var(--font-display);
  font-size: 1.5rem;
  font-weight: 700;
}

.brand-subtitle {
  font-size: 0.875rem;
  color: var(--text-muted);
}

.auth-tabs {
  display: grid;
  grid-template-columns: 1fr 1fr;
  background: var(--bg-base);
  padding: 4px;
  border-radius: var(--radius-md);
  margin-bottom: 20px;
}

.auth-tab {
  background: transparent;
  border: none;
  color: var(--text-muted);
  padding: 9px 12px;
  border-radius: var(--radius-sm);
  font-weight: 600;
  cursor: pointer;
  transition: all 0.15s ease;
}

.auth-tab.active {
  background: var(--bg-elevated);
  color: var(--text-primary);
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 6px;
  margin-bottom: 16px;
}

.form-group label {
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--text-secondary);
}

input[type="text"],
input[type="email"],
input[type="password"],
input[type="url"],
input[type="number"],
input[type="search"],
select,
textarea {
  background: var(--bg-base);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  color: var(--text-primary);
  padding: 9px 12px;
  font-size: 0.9rem;
  font-family: inherit;
}

input:focus,
select:focus,
textarea:focus {
  outline: 2px solid var(--border-focus);
  outline-offset: 1px;
}

.privacy-notice {
  margin-top: 20px;
  padding-top: 16px;
  border-top: 1px solid var(--border-subtle);
  font-size: 0.78rem;
  color: var(--text-muted);
}

/* BUTTONS & BADGES */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  border: 1px solid transparent;
  border-radius: var(--radius-sm);
  padding: 8px 14px;
  font-size: 0.875rem;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.15s ease, transform 0.1s ease;
  color: var(--text-primary);
  background: var(--bg-elevated);
}

.btn:disabled {
  opacity: 0.45;
  cursor: not-allowed;
}

.btn-primary {
  background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
  color: #fff;
}

.btn-primary:hover:not(:disabled) {
  filter: brightness(1.1);
}

.btn-secondary {
  background: var(--bg-elevated);
  border-color: var(--border-subtle);
}

.btn-secondary:hover:not(:disabled) {
  background: var(--bg-hover);
}

.btn-accent {
  background: rgba(14, 165, 233, 0.16);
  border-color: rgba(56, 189, 248, 0.4);
  color: #38bdf8;
}

.btn-ghost {
  background: transparent;
  color: var(--text-secondary);
}

.btn-ghost:hover:not(:disabled) {
  background: var(--bg-elevated);
}

.btn-danger {
  background: rgba(239, 68, 68, 0.2);
  border-color: rgba(239, 68, 68, 0.5);
  color: #fca5a5;
}

.btn-danger-ghost {
  background: transparent;
  color: #fca5a5;
}

.btn-danger-ghost:hover:not(:disabled) {
  background: rgba(239, 68, 68, 0.15);
}

.btn-sm {
  padding: 6px 11px;
  font-size: 0.82rem;
}

.btn-xs {
  padding: 4px 9px;
  font-size: 0.76rem;
}

.btn-full {
  width: 100%;
}

.btn-play {
  background: var(--accent-primary);
  color: #fff;
  padding: 7px 18px;
  border-radius: 999px;
}

.badge {
  display: inline-flex;
  align-items: center;
  padding: 2px 8px;
  border-radius: 999px;
  font-size: 0.72rem;
  font-weight: 600;
}

.badge-accent {
  background: rgba(14, 165, 233, 0.2);
  color: #38bdf8;
}

.badge-muted {
  background: var(--bg-elevated);
  color: var(--text-secondary);
}

.badge-timing {
  background: rgba(16, 185, 129, 0.18);
  color: #34d399;
}

/* APP SHELL & TOP NAV */
.app-shell {
  display: flex;
  flex-direction: column;
  height: 100vh;
}

.top-nav {
  height: 56px;
  background: var(--bg-surface);
  border-bottom: 1px solid var(--border-subtle);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 16px;
  flex-shrink: 0;
}

.nav-left,
.nav-center,
.nav-right {
  display: flex;
  align-items: center;
  gap: 10px;
}

.brand-compact {
  display: flex;
  align-items: center;
  gap: 8px;
}

.brand-logo-sm {
  width: 30px;
  height: 30px;
  border-radius: 8px;
  background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 0.82rem;
}

.brand-name {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.08rem;
}

.nav-pill {
  background: transparent;
  border: none;
  color: var(--text-secondary);
  padding: 6px 14px;
  border-radius: 999px;
  font-size: 0.85rem;
  font-weight: 600;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.nav-pill.active {
  background: var(--bg-elevated);
  color: #38bdf8;
}

.queue-count-badge {
  background: var(--accent-primary);
  color: #fff;
  font-size: 0.7rem;
  padding: 1px 6px;
  border-radius: 999px;
}

.user-pill {
  font-size: 0.8rem;
  color: var(--text-muted);
  padding: 4px 10px;
  background: var(--bg-base);
  border-radius: 999px;
}

/* GLOBAL QUEUE BAR */
.global-queue-bar {
  background: rgba(14, 165, 233, 0.14);
  border-bottom: 1px solid rgba(56, 189, 248, 0.35);
  padding: 6px 16px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.82rem;
  flex-shrink: 0;
}

.queue-bar-info {
  display: flex;
  align-items: center;
  gap: 8px;
}

.spinner-dot {
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: #38bdf8;
  animation: pulseDot 1.1s infinite ease-in-out;
}

@keyframes pulseDot {
  0%, 100% { transform: scale(0.85); opacity: 0.5; }
  50% { transform: scale(1.25); opacity: 1; }
}

/* 3-COLUMN STUDY WORKSPACE */
.study-workspace {
  flex: 1;
  display: grid;
  grid-template-columns: 310px 1fr 350px;
  min-height: 0;
  overflow: hidden;
}

.library-panel,
.vocab-panel {
  background: var(--bg-surface);
  display: flex;
  flex-direction: column;
  min-height: 0;
}

.library-panel {
  border-right: 1px solid var(--border-subtle);
}

.vocab-panel {
  border-left: 1px solid var(--border-subtle);
}

.panel-header {
  padding: 12px 14px;
  border-bottom: 1px solid var(--border-subtle);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
}

.panel-title {
  font-size: 0.96rem;
  font-weight: 700;
}

.panel-subtitle {
  font-size: 0.75rem;
  color: var(--text-muted);
}

.upload-actions {
  display: flex;
  gap: 6px;
}

.library-filters {
  padding: 10px 12px;
  display: flex;
  flex-direction: column;
  gap: 8px;
  border-bottom: 1px solid var(--border-subtle);
}

.filter-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 6px;
}

.input-sm,
.select-sm {
  padding: 6px 9px;
  font-size: 0.8rem;
  width: 100%;
}

.library-batch-bar {
  padding: 8px 12px;
  border-bottom: 1px solid var(--border-subtle);
}

.set-coverage-box {
  padding: 8px 12px;
  background: rgba(99, 102, 241, 0.1);
  border-bottom: 1px solid var(--border-subtle);
  font-size: 0.75rem;
  color: var(--text-secondary);
}

.library-list {
  flex: 1;
  overflow-y: auto;
  padding: 8px;
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.library-item {
  padding: 10px 12px;
  border-radius: var(--radius-md);
  background: var(--bg-base);
  border: 1px solid transparent;
  cursor: pointer;
  transition: background 0.15s ease, border-color 0.15s ease;
}

.library-item:hover {
  background: var(--bg-elevated);
}

.library-item.active {
  background: rgba(14, 165, 233, 0.12);
  border-color: var(--accent-primary);
}

.lib-item-top {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 6px;
  margin-bottom: 4px;
}

.lib-item-name {
  font-size: 0.85rem;
  font-weight: 600;
  word-break: break-word;
}

.lib-item-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  font-size: 0.73rem;
  color: var(--text-muted);
}

/* CENTER STAGE: STICKY PLAYER + TRANSCRIPT */
.center-stage {
  display: flex;
  flex-direction: column;
  min-height: 0;
  background: var(--bg-base);
}

.player-dock {
  background: var(--bg-surface);
  border-bottom: 1px solid var(--border-subtle);
  padding: 12px 18px;
  display: flex;
  flex-direction: column;
  gap: 10px;
  flex-shrink: 0;
}

.player-track-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 8px;
}

.track-title-wrap {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
}

.track-title {
  font-size: 1.05rem;
  font-weight: 700;
}

.track-actions {
  display: flex;
  align-items: center;
  gap: 6px;
  flex-wrap: wrap;
}

.player-timeline-row {
  display: flex;
  align-items: center;
  gap: 12px;
}

.time-readout {
  font-variant-numeric: tabular-nums;
  font-size: 0.8rem;
  color: var(--text-secondary);
  min-width: 58px;
}

.seek-slider {
  flex: 1;
  accent-color: var(--accent-primary);
  cursor: pointer;
}

.rest-countdown-banner {
  background: rgba(245, 158, 11, 0.16);
  border: 1px solid rgba(245, 158, 11, 0.45);
  color: #fcd34d;
  padding: 6px 12px;
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.82rem;
}

.player-controls-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 10px;
}

.transport-group,
.mode-group {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
}

.control-pill {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: var(--bg-base);
  border: 1px solid var(--border-subtle);
  padding: 4px 10px;
  border-radius: 999px;
  font-size: 0.77rem;
  color: var(--text-secondary);
}

.select-inline {
  background: transparent;
  border: none;
  color: var(--text-primary);
  font-weight: 600;
  padding: 2px 4px;
  font-size: 0.78rem;
}

.input-number-inline {
  width: 44px;
  padding: 2px 4px;
  font-size: 0.78rem;
  text-align: center;
}

.loop-badge {
  background: var(--accent-secondary);
  color: #fff;
  padding: 1px 6px;
  border-radius: 999px;
  font-size: 0.7rem;
}

.track-job-banner {
  background: rgba(56, 189, 248, 0.12);
  border-bottom: 1px solid rgba(56, 189, 248, 0.3);
  padding: 6px 18px;
  font-size: 0.8rem;
  color: #38bdf8;
}

/* ACTIVE SENTENCE TRANSLATION CARD */
.active-translation-card {
  margin: 12px 18px 0;
  padding: 12px 16px;
  background: linear-gradient(135deg, rgba(14, 165, 233, 0.12), rgba(99, 102, 241, 0.1));
  border: 1px solid rgba(56, 189, 248, 0.35);
  border-radius: var(--radius-md);
  flex-shrink: 0;
}

.active-trans-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 6px;
}

.active-trans-label {
  font-size: 0.74rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: #38bdf8;
}

.active-sentence-en {
  font-size: 0.96rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 4px;
}

.active-sentence-vi {
  font-size: 0.92rem;
  color: #fde68a;
}

/* TRANSCRIPT SEGMENTS & WORD HIGHLIGHT */
.transcript-viewport {
  flex: 1;
  overflow-y: auto;
  padding: 16px 18px 36px;
}

.segments-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.segment-card {
  padding: 12px 16px;
  border-radius: var(--radius-md);
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  cursor: pointer;
  transition: border-color 0.15s ease, background 0.15s ease;
}

.segment-card:hover {
  border-color: rgba(56, 189, 248, 0.45);
}

.segment-card.active-segment {
  background: var(--bg-active-seg);
  border-color: var(--accent-primary);
  box-shadow: inset 3px 0 0 var(--accent-primary);
}

.segment-meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.75rem;
  color: var(--text-muted);
  margin-bottom: 6px;
}

.segment-english {
  font-size: 1.02rem;
  line-height: 1.65;
  color: var(--text-primary);
}

.transcript-word {
  padding: 1px 3px;
  border-radius: 4px;
  transition: background-color 0.08s ease, color 0.08s ease;
}

.transcript-word.active-word {
  background-color: var(--accent-word-bg);
  color: var(--accent-word-text);
  font-weight: 700;
  text-decoration: underline;
}

.segment-translation {
  margin-top: 6px;
  padding-top: 6px;
  border-top: 1px dashed var(--border-subtle);
  font-size: 0.9rem;
  color: #cbd5e1;
}

.segment-card.active-segment .segment-translation {
  color: #fde68a;
  font-weight: 500;
}

/* VOCABULARY & TIPS PANEL */
.vocab-content-area {
  flex: 1;
  overflow-y: auto;
  padding: 12px 14px;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.section-heading {
  font-size: 0.85rem;
  font-weight: 700;
  color: #38bdf8;
  margin-bottom: 8px;
}

.tips-box {
  background: rgba(16, 185, 129, 0.08);
  border: 1px solid rgba(16, 185, 129, 0.28);
  border-radius: var(--radius-md);
  padding: 12px;
}

.tips-list {
  padding-left: 16px;
  display: flex;
  flex-direction: column;
  gap: 6px;
  font-size: 0.83rem;
  color: var(--text-secondary);
}

.vocab-cards-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.vocab-card {
  background: var(--bg-base);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 12px;
}

.vocab-card-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
  margin-bottom: 4px;
}

.vocab-term {
  font-weight: 700;
  font-size: 0.96rem;
  color: #38bdf8;
}

.vocab-ipa {
  font-size: 0.8rem;
  color: var(--text-muted);
}

.vocab-pos {
  font-size: 0.72rem;
  background: var(--bg-elevated);
  padding: 1px 6px;
  border-radius: 4px;
}

.vocab-meaning {
  font-size: 0.88rem;
  font-weight: 600;
  color: #fde68a;
  margin-bottom: 6px;
}

.vocab-evidence {
  font-size: 0.78rem;
  font-style: italic;
  color: var(--text-secondary);
  background: var(--bg-surface);
  padding: 6px 8px;
  border-radius: 4px;
  margin-bottom: 6px;
}

.vocab-synonyms {
  font-size: 0.76rem;
  color: var(--text-muted);
}

/* EDITOR PANEL */
.editor-panel {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 16px;
}

.editor-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 14px;
  gap: 12px;
}

.editor-rows {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.editor-row {
  display: grid;
  grid-template-columns: 95px 95px 1fr auto;
  gap: 8px;
  align-items: start;
  background: var(--bg-base);
  padding: 10px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border-subtle);
}

/* SECONDARY SCREENS (QUEUE & SETTINGS) */
.secondary-screen {
  flex: 1;
  overflow-y: auto;
  padding: 24px;
}

.screen-container {
  max-width: 1180px;
  margin: 0 auto;
}

.narrow-container {
  max-width: 760px;
}

.screen-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  margin-bottom: 20px;
}

.queue-summary-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 12px;
  margin-bottom: 20px;
}

.summary-stat-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 14px;
}

.summary-stat-value {
  font-size: 1.4rem;
  font-weight: 700;
}

.table-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  overflow-x: auto;
}

.queue-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.85rem;
}

.queue-table th,
.queue-table td {
  padding: 12px 14px;
  text-align: left;
  border-bottom: 1px solid var(--border-subtle);
}

.stage-pill {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 2px 8px;
  border-radius: 999px;
  font-size: 0.74rem;
  font-weight: 600;
}

.stage-done { background: rgba(16, 185, 129, 0.18); color: #34d399; }
.stage-running { background: rgba(14, 165, 233, 0.22); color: #38bdf8; }
.stage-error { background: rgba(239, 68, 68, 0.22); color: #fca5a5; }
.stage-skipped { background: rgba(148, 163, 184, 0.18); color: #cbd5e1; }
.stage-pending { background: rgba(245, 158, 11, 0.15); color: #fcd34d; }

/* SETTINGS */
.settings-section {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 20px;
  margin-top: 16px;
}

.settings-section h3 {
  margin-bottom: 12px;
  font-size: 1rem;
}

.form-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 14px;
}

.checkbox-row {
  display: flex;
  flex-direction: column;
  gap: 10px;
  margin-top: 10px;
  font-size: 0.88rem;
}

.settings-footer {
  margin-top: 20px;
  display: flex;
  justify-content: flex-end;
}

/* MODAL & TOAST */
.modal-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.68);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
  z-index: 1000;
}

.modal-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  max-width: 500px;
  width: 100%;
  padding: 24px;
  box-shadow: var(--shadow-card);
}

.modal-title {
  margin-bottom: 12px;
}

.modal-body {
  color: var(--text-secondary);
  font-size: 0.9rem;
  margin-bottom: 20px;
}

.modal-actions {
  display: flex;
  justify-content: flex-end;
  gap: 10px;
}

.toast-container {
  position: fixed;
  bottom: 20px;
  right: 20px;
  display: flex;
  flex-direction: column;
  gap: 8px;
  z-index: 1100;
}

.toast-item {
  background: var(--bg-elevated);
  border: 1px solid var(--border-focus);
  color: var(--text-primary);
  padding: 10px 16px;
  border-radius: var(--radius-md);
  font-size: 0.85rem;
  box-shadow: var(--shadow-card);
}

.empty-state {
  text-align: center;
  padding: 48px 20px;
  color: var(--text-muted);
}

.empty-state-sm {
  font-size: 0.83rem;
  color: var(--text-muted);
  padding: 16px;
  background: var(--bg-base);
  border-radius: var(--radius-md);
}

.text-muted {
  color: var(--text-muted);
  font-size: 0.82rem;
}

.alert-banner {
  padding: 10px 12px;
  border-radius: var(--radius-sm);
  font-size: 0.84rem;
  margin-bottom: 14px;
}

.alert-error {
  background: rgba(239, 68, 68, 0.16);
  border: 1px solid rgba(239, 68, 68, 0.45);
  color: #fca5a5;
}

.mobile-only {
  display: none;
}

@media (max-width: 1100px) {
  .study-workspace {
    grid-template-columns: 260px 1fr;
  }
  .vocab-panel {
    display: none;
  }
}

@media (max-width: 768px) {
  .mobile-only {
    display: inline-flex;
  }
  .study-workspace {
    grid-template-columns: 1fr;
  }
  .library-panel {
    position: fixed;
    top: 56px;
    left: 0;
    bottom: 0;
    width: 290px;
    z-index: 500;
    transform: translateX(-100%);
    transition: transform 0.2s ease;
  }
  .library-panel.open {
    transform: translateX(0);
  }
  .form-grid {
    grid-template-columns: 1fr;
  }
}