:root {
  --bg: #1a1a2e;
  --card-bg: #16213e;
  --text: #e0e0e0;
  --text-secondary: #8a8a9a;
  --accent: #4fc3f7;
  --correct: #66bb6a;
  --wrong: #ef5350;
  --border: #2a2a4a;
  --radius: 12px;
  --shadow: 0 2px 12px rgba(0, 0, 0, 0.3);
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  min-height: 100vh;
  display: flex;
  justify-content: center;
  padding: 2rem 1rem;
  padding-top: max(2rem, env(safe-area-inset-top));
  padding-bottom: max(2rem, env(safe-area-inset-bottom));
  padding-left: max(1rem, env(safe-area-inset-left));
  padding-right: max(1rem, env(safe-area-inset-right));
  -webkit-tap-highlight-color: transparent;
}

.container {
  width: 100%;
  max-width: 640px;
}

h1 {
  text-align: center;
  font-size: 1.75rem;
  font-weight: 700;
  margin-bottom: 1.5rem;
}

/* Settings Panel */
.settings {
  background: var(--card-bg);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 1rem 1.25rem;
  margin-bottom: 1rem;
}

.settings summary {
  font-weight: 600;
  cursor: pointer;
  user-select: none;
  font-size: 1rem;
  color: var(--text-secondary);
}

.settings-row {
  display: flex;
  align-items: center;
  gap: 1rem;
  margin-top: 0.75rem;
  flex-wrap: wrap;
}

.setting-group {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.setting-label {
  font-size: 0.85rem;
  color: var(--text);
  font-weight: 600;
}

.setting-hint {
  font-size: 0.75rem;
  color: var(--text-secondary);
}

#threshold-select {
  padding: 0.3rem 0.5rem;
  font-size: 0.85rem;
  border: 1px solid var(--border);
  border-radius: 6px;
  background: var(--bg);
  color: var(--text);
  cursor: pointer;
  font-family: inherit;
}

.setting-divider {
  height: 1px;
  background: var(--border);
  margin: 0.75rem 0 0.5rem;
}

.setting-sub-label {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-secondary);
  margin-bottom: 0.25rem;
}

.tense-actions {
  display: flex;
  gap: 0.5rem;
  margin: 0.75rem 0;
}

.tense-actions button {
  padding: 0.35rem 0.75rem;
  font-size: 0.8rem;
  border: 1px solid var(--border);
  border-radius: 6px;
  background: var(--bg);
  cursor: pointer;
  color: var(--text);
  transition: background 0.15s;
}

.tense-actions button:hover {
  background: var(--border);
}

.tense-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: 0.5rem;
}

.tense-grid label {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.9rem;
  cursor: pointer;
  padding: 0.25rem 0;
}

.tense-grid input[type="checkbox"] {
  accent-color: var(--accent);
  width: 16px;
  height: 16px;
}

/* Stats Bar */
.stats-bar {
  display: flex;
  justify-content: center;
  gap: 1.5rem;
  margin-bottom: 1rem;
  flex-wrap: wrap;
}

.stat {
  font-size: 0.9rem;
  color: var(--text-secondary);
}

.correct-stat strong {
  color: var(--correct);
}

.wrong-stat strong {
  color: var(--wrong);
}

.streak-stat strong {
  color: var(--accent);
}

/* Bookmark Button */
.bookmark-btn {
  width: 28px;
  height: 28px;
  font-size: 1rem;
  border: 2px solid #f5a623;
  border-radius: 50%;
  background: transparent;
  color: #f5a623;
  cursor: pointer;
  margin-left: 0.35rem;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  vertical-align: middle;
  transition: background 0.15s, color 0.15s, transform 0.15s;
}

.bookmark-btn:hover {
  background: #f5a623;
  color: var(--card-bg);
}

.bookmark-btn.active {
  background: #f5a623;
  color: var(--card-bg);
  transform: scale(1.1);
}

/* Bookmarks Panel */
.bookmarks-panel {
  background: var(--card-bg);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 0.75rem 1rem;
  margin-top: 1rem;
}

.bookmarks-panel summary {
  font-weight: 600;
  cursor: pointer;
  user-select: none;
  font-size: 1rem;
  color: #f5a623;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.bookmark-count {
  background: #f5a623;
  color: var(--card-bg);
  font-size: 0.75rem;
  font-weight: 700;
  padding: 0.1rem 0.45rem;
  border-radius: 10px;
}

.bookmarks-list {
  margin-top: 0.5rem;
}

.bookmark-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.5rem 0.4rem;
  border-bottom: 1px solid var(--border);
  font-size: 0.85rem;
  animation: slide-in 0.3s ease;
}

.bookmark-item:last-child {
  border-bottom: none;
}

.bookmark-item-text {
  flex: 1;
}

.bookmark-item-verb {
  font-weight: 700;
  color: var(--text);
}

.bookmark-item-detail {
  color: var(--text-secondary);
  font-size: 0.78rem;
}

.bookmark-item-answer {
  color: var(--accent);
  font-size: 0.78rem;
  font-style: italic;
}

.bookmark-remove {
  width: 24px;
  height: 24px;
  border: none;
  background: transparent;
  color: var(--text-secondary);
  cursor: pointer;
  font-size: 1rem;
  border-radius: 4px;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  margin-left: 0.5rem;
}

.bookmark-remove:hover {
  background: var(--wrong);
  color: white;
}

/* Batch Indicator */
.batch-indicator {
  background: var(--card-bg);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 0.75rem 1rem;
  margin-bottom: 1rem;
}

.batch-header {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.75rem;
  margin-bottom: 0.25rem;
}

.batch-indicator #batch-label {
  font-weight: 700;
  font-size: 0.9rem;
  color: var(--accent);
}

.batch-nav {
  width: 30px;
  height: 30px;
  border: 1px solid var(--border);
  border-radius: 6px;
  background: var(--bg);
  color: var(--text);
  cursor: pointer;
  font-size: 1rem;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background 0.15s, border-color 0.15s;
}

.batch-nav:hover {
  background: var(--border);
  border-color: var(--accent);
}

.batch-nav:disabled {
  opacity: 0.3;
  cursor: default;
}

.batch-verbs {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(100px, 1fr));
  gap: 0.5rem;
  margin-top: 0.5rem;
}

.verb-card {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 0.45rem 0.55rem;
  transition: border-color 0.2s, background 0.2s;
}

.verb-card.done {
  border-color: var(--correct);
  background: #1b3a2a;
}

.verb-card-name {
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 0.15rem;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.verb-card.done .verb-card-name {
  color: var(--correct);
}

.verb-card-dots {
  display: flex;
  flex-wrap: wrap;
  gap: 3px;
}

.dot {
  width: 10px;
  height: 10px;
  border-radius: 3px;
  background: var(--border);
  transition: background 0.3s, box-shadow 0.3s;
}

.dot.in-progress[data-prog="1"] {
  background: #2a4a5a;
}
.dot.in-progress[data-prog="2"] {
  background: #2a5a6a;
}
.dot.in-progress[data-prog="3"] {
  background: #2a6a7a;
}
.dot.in-progress[data-prog="4"] {
  background: #2a7a8a;
}

.dot.mastered {
  background: var(--correct);
  box-shadow: 0 0 4px rgba(102, 187, 106, 0.5);
}

/* Progress Bar */
.progress-bar-container {
  margin-bottom: 1rem;
}

.progress-bar-label {
  display: flex;
  justify-content: space-between;
  font-size: 0.8rem;
  color: var(--text-secondary);
  margin-bottom: 0.3rem;
}

.progress-bar-track {
  height: 10px;
  background: var(--border);
  border-radius: 5px;
  overflow: hidden;
}

.progress-bar-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--accent), var(--correct));
  border-radius: 5px;
  transition: width 0.4s ease;
}

/* Quiz Area */
.quiz-area {
  background: var(--card-bg);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 1.5rem;
}

.prompt {
  margin-bottom: 1rem;
}

.verb-display,
.tense-display {
  margin-bottom: 0.5rem;
}

.label {
  font-size: 0.85rem;
  color: var(--text-secondary);
  margin-right: 0.5rem;
}

.value {
  font-weight: 600;
  font-size: 1.1rem;
}

.value .star {
  color: #f5a623;
}

.verb-meaning {
  font-size: 0.85rem;
  color: var(--text-secondary);
  font-style: italic;
  margin-left: 0.5rem;
}

.pronoun-display {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin-top: 1rem;
}

.pronoun {
  font-size: 1.3rem;
  font-weight: 700;
  min-width: 60px;
  text-align: right;
  color: var(--accent);
}

#answer-input {
  flex: 1;
  font-size: 1.2rem;
  padding: 0.6rem 0.75rem;
  border: 2px solid var(--border);
  border-radius: 8px;
  outline: none;
  font-family: inherit;
  transition: border-color 0.2s;
  background: var(--bg);
  color: var(--text);
}

#answer-input:focus {
  border-color: var(--accent);
}

#answer-input.flash-correct {
  border-color: var(--correct);
  background: #1b3a2a;
  animation: flash-green 0.4s ease;
}

#answer-input.flash-wrong {
  border-color: var(--wrong);
  background: #3a1b1b;
  animation: flash-red 0.4s ease;
}

@keyframes flash-green {
  0% { background: #2a5a3a; }
  100% { background: #1b3a2a; }
}

@keyframes flash-red {
  0% { background: #5a2a2a; }
  100% { background: #3a1b1b; }
}

/* Feedback */
.feedback {
  padding: 0.75rem;
  border-radius: 8px;
  margin-bottom: 1rem;
  font-weight: 600;
  text-align: center;
  font-size: 1rem;
}

.feedback.correct {
  background: #1b3a2a;
  color: #66bb6a;
}

.feedback.wrong {
  background: #3a1b1b;
  color: #ef5350;
}

.feedback.hidden {
  display: none;
}

/* Submit Button */
.submit-btn {
  width: 100%;
  padding: 0.75rem;
  font-size: 1rem;
  font-weight: 600;
  background: var(--accent);
  color: white;
  border: none;
  border-radius: 8px;
  cursor: pointer;
  transition: opacity 0.15s;
  margin-bottom: 1rem;
}

.submit-btn:hover {
  opacity: 0.85;
}

/* Accent Helper */
.accent-helper {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.35rem;
  padding-top: 0.5rem;
  border-top: 1px solid var(--border);
}

.accent-label {
  font-size: 0.8rem;
  color: var(--text-secondary);
  margin-right: 0.25rem;
}

.accent-btn {
  width: 36px;
  height: 36px;
  font-size: 1rem;
  border: 1px solid var(--border);
  border-radius: 6px;
  background: var(--bg);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background 0.15s;
  font-family: inherit;
}

.accent-btn:hover {
  background: var(--border);
}

/* Help Button */
.help-btn {
  width: 28px;
  height: 28px;
  font-size: 0.85rem;
  font-weight: 700;
  border: 2px solid var(--accent);
  border-radius: 50%;
  background: transparent;
  color: var(--accent);
  cursor: pointer;
  margin-left: 0.5rem;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  vertical-align: middle;
  transition: background 0.15s, color 0.15s;
}

.help-btn:hover {
  background: var(--accent);
  color: white;
}

/* Modal */
.modal {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.4);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 100;
  padding: 1rem;
}

.modal.hidden {
  display: none;
}

.modal-content {
  background: var(--card-bg);
  border-radius: var(--radius);
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.2);
  width: 100%;
  max-width: 600px;
  max-height: 80vh;
  display: flex;
  flex-direction: column;
}

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

.modal-header h2 {
  font-size: 1.1rem;
  font-weight: 700;
}

.modal-close {
  width: 32px;
  height: 32px;
  font-size: 1.4rem;
  border: none;
  background: transparent;
  cursor: pointer;
  color: var(--text-secondary);
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 6px;
}

.modal-close:hover {
  background: var(--bg);
}

.modal-body {
  padding: 1.25rem;
  overflow-y: auto;
}

.pattern-section {
  margin-bottom: 1.25rem;
}

.pattern-section:last-child {
  margin-bottom: 0;
}

.pattern-section h3 {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--accent);
  margin-bottom: 0.5rem;
}

.help-description {
  font-size: 0.9rem;
  color: var(--text);
  line-height: 1.6;
  padding: 0.5rem 0.65rem;
  background: var(--bg);
  border-radius: 8px;
  border-left: 3px solid var(--accent);
}

.help-usage-list {
  list-style: none;
  padding: 0;
  margin: 0;
}

.help-usage-list li {
  font-size: 0.82rem;
  color: var(--text);
  padding: 0.4rem 0.5rem;
  border-bottom: 1px solid var(--border);
  line-height: 1.5;
}

.help-usage-list li:last-child {
  border-bottom: none;
}

.pattern-section .pattern-note {
  font-size: 0.8rem;
  color: var(--text-secondary);
  margin-bottom: 0.5rem;
  font-style: italic;
}

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

.pattern-table th {
  text-align: left;
  padding: 0.35rem 0.5rem;
  background: var(--bg);
  font-weight: 600;
  color: var(--text-secondary);
  font-size: 0.8rem;
}

.pattern-table td {
  padding: 0.3rem 0.5rem;
  border-bottom: 1px solid var(--bg);
}

.pattern-table td:first-child {
  font-weight: 600;
  color: var(--accent);
  width: 60px;
}

/* Mastered Catalog */
.catalog-section {
  margin-top: 1.5rem;
}

.catalog-title {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--correct);
  margin-bottom: 0.75rem;
}

.catalog-tense {
  background: var(--card-bg);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  margin-bottom: 0.5rem;
  overflow: hidden;
}

.catalog-tense-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.7rem 1rem;
  cursor: pointer;
  user-select: none;
  transition: background 0.15s;
}

.catalog-tense-header:hover {
  background: var(--border);
}

.catalog-tense-name {
  font-weight: 600;
  font-size: 0.9rem;
  color: var(--text);
}

.catalog-tense-progress {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.catalog-tense-fraction {
  font-size: 0.75rem;
  color: var(--text-secondary);
}

.catalog-tense-ring {
  width: 28px;
  height: 28px;
  position: relative;
}

.catalog-tense-ring svg {
  transform: rotate(-90deg);
}

.catalog-tense-ring .ring-bg {
  fill: none;
  stroke: var(--border);
  stroke-width: 3;
}

.catalog-tense-ring .ring-fill {
  fill: none;
  stroke: var(--correct);
  stroke-width: 3;
  stroke-linecap: round;
  transition: stroke-dashoffset 0.4s ease;
}

.catalog-tense-chevron {
  font-size: 0.7rem;
  color: var(--text-secondary);
  transition: transform 0.2s;
  margin-left: 0.35rem;
}

.catalog-tense.open .catalog-tense-chevron {
  transform: rotate(90deg);
}

.catalog-tense-body {
  display: none;
  padding: 0 1rem 0.75rem 1rem;
}

.catalog-tense.open .catalog-tense-body {
  display: block;
}

.catalog-verb-group {
  margin-bottom: 0.5rem;
}

.catalog-verb-group:last-child {
  margin-bottom: 0;
}

.catalog-verb-name {
  font-weight: 700;
  font-size: 0.82rem;
  color: var(--accent);
  margin-bottom: 0.2rem;
}

.catalog-verb-forms {
  display: flex;
  flex-wrap: wrap;
  gap: 0.3rem;
}

.catalog-form-pill {
  font-size: 0.72rem;
  padding: 0.15rem 0.45rem;
  border-radius: 4px;
  background: #1b3a2a;
  color: var(--correct);
  border: 1px solid rgba(102, 187, 106, 0.3);
}

@keyframes slide-in {
  from { opacity: 0; transform: translateX(-10px); }
  to { opacity: 1; transform: translateX(0); }
}

/* Speaker button */
.speak-btn {
  width: 38px;
  height: 38px;
  font-size: 1.05rem;
  border: 1px solid var(--border);
  border-radius: 50%;
  background: var(--bg);
  color: var(--accent);
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  transition: background 0.15s, border-color 0.15s, transform 0.1s;
  line-height: 1;
  padding: 0;
}

.speak-btn:hover {
  background: var(--border);
  border-color: var(--accent);
}

.speak-btn:active {
  transform: scale(0.94);
}

/* Auto-pronounce checkbox label */
.setting-checkbox-label {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  cursor: pointer;
  user-select: none;
}

.setting-checkbox-label input[type="checkbox"] {
  accent-color: var(--accent);
  width: 16px;
  height: 16px;
  cursor: pointer;
}

/* Responsive */
@media (max-width: 640px) {
  body {
    padding: 0.75rem 0.5rem;
  }

  h1 {
    font-size: 1.4rem;
    margin-bottom: 1rem;
  }

  /* Settings: stack vertically, full width */
  .settings {
    padding: 0.85rem 0.9rem;
  }

  .settings-row {
    gap: 0.75rem;
  }

  .setting-group {
    flex-wrap: wrap;
  }

  #threshold-select {
    font-size: 16px; /* prevent iOS zoom */
    padding: 0.4rem 0.5rem;
  }

  .tense-grid {
    grid-template-columns: 1fr 1fr;
    gap: 0.4rem;
  }

  .tense-grid label {
    font-size: 0.85rem;
    padding: 0.4rem 0;
    min-height: 32px;
  }

  .tense-grid input[type="checkbox"] {
    width: 18px;
    height: 18px;
  }

  .tense-actions button {
    padding: 0.5rem 0.85rem;
    font-size: 0.85rem;
    min-height: 36px;
  }

  /* Stats: keep on one line but smaller gap */
  .stats-bar {
    gap: 0.85rem;
    font-size: 0.85rem;
  }

  /* Batch indicator */
  .batch-indicator {
    padding: 0.7rem 0.75rem;
  }

  .batch-header {
    gap: 0.5rem;
  }

  .batch-nav {
    width: 36px;
    height: 36px;
    font-size: 1.1rem;
  }

  .batch-verbs {
    grid-template-columns: repeat(auto-fill, minmax(88px, 1fr));
    gap: 0.4rem;
  }

  .verb-card {
    padding: 0.4rem 0.45rem;
  }

  .verb-card-name {
    font-size: 0.78rem;
  }

  /* Quiz area */
  .quiz-area {
    padding: 1rem;
  }

  .pronoun-display {
    flex-wrap: wrap;
    gap: 0.4rem;
  }

  .pronoun {
    font-size: 1.2rem;
    min-width: 50px;
  }

  #answer-input {
    font-size: 16px; /* prevent iOS auto-zoom */
    padding: 0.7rem 0.75rem;
    flex: 1 1 100%;
    order: 3;
  }

  .speak-btn {
    width: 44px;
    height: 44px;
    font-size: 1.1rem;
  }

  .submit-btn {
    padding: 0.9rem;
    font-size: 1rem;
    min-height: 48px;
  }

  /* Accent helper — thumb-friendly */
  .accent-helper {
    gap: 0.4rem;
  }

  .accent-btn {
    width: 44px;
    height: 44px;
    font-size: 1.05rem;
  }

  .accent-label {
    flex-basis: 100%;
    margin-bottom: 0.25rem;
  }

  /* Catalog */
  .catalog-tense-header {
    padding: 0.75rem 0.85rem;
  }

  .catalog-tense-fraction {
    font-size: 0.72rem;
  }

  .catalog-verb-forms {
    gap: 0.25rem;
  }

  .catalog-form-pill {
    font-size: 0.72rem;
    padding: 0.2rem 0.45rem;
  }

  /* Bookmarks */
  .bookmarks-panel {
    padding: 0.7rem 0.85rem;
  }

  /* Modal: full-screen on phones */
  .modal {
    padding: 0;
    align-items: stretch;
  }

  .modal-content {
    max-width: 100%;
    max-height: 100vh;
    /* Respect iOS notch / status bar in standalone PWA */
    padding-top: env(safe-area-inset-top);
    padding-bottom: env(safe-area-inset-bottom);
    height: 100vh;
    border-radius: 0;
  }

  .modal-header {
    padding: 0.85rem 1rem;
    position: sticky;
    top: 0;
    background: var(--card-bg);
    z-index: 2;
    min-height: 52px;
  }

  .modal-close {
    width: 44px;
    height: 44px;
    font-size: 1.8rem;
    /* Hard-guarantee the tap target stays clear of iOS chrome */
    position: relative;
    z-index: 3;
  }

  .modal-body {
    padding: 1rem;
  }
}

@media (max-width: 400px) {
  .tense-grid {
    grid-template-columns: 1fr;
  }
}

/* ============ Sentence context mode ============ */
.sentence-display {
  background: rgba(79, 195, 247, 0.08);
  border: 1px solid rgba(79, 195, 247, 0.25);
  border-radius: var(--radius);
  padding: 0.9rem 1rem;
  margin: 0.25rem 0 0.9rem 0;
  font-size: 1.05rem;
  line-height: 1.55;
  color: var(--text);
  word-wrap: break-word;
  overflow-wrap: break-word;
}
.sentence-display.hidden {
  display: none;
}
.sentence-blank {
  display: inline-block;
  min-width: 2.8em;
  border-bottom: 2px solid var(--accent);
  color: var(--accent);
  letter-spacing: 0.1em;
  padding: 0 0.2em;
  margin: 0 0.15em;
}
.sentence-hint {
  color: var(--text-secondary);
  font-style: italic;
  font-size: 0.9em;
  white-space: nowrap;
}

@media (max-width: 640px) {
  .sentence-display {
    font-size: 1rem;
    padding: 0.75rem 0.85rem;
  }
}

/* PWA / standalone tweaks when launched from home screen */
@media all and (display-mode: standalone) {
  body {
    /* Respect the iOS status bar black-translucent style */
    padding-top: max(1.5rem, env(safe-area-inset-top));
  }
}