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

:root {
  --ink: #1a1410;
  --paper: #f5f0e8;
  --offwhite: #fffff8;
  --aged: #e8dfc8;
  --vermillion: #b8432f;
  --gold: #b8860b;
  --muted: #7a746d;
  --faint: #ccc5ba;
}

body {
  font-display: swap;
  background-color: var(--paper);
  color: var(--ink);
  font-family: 'Cormorant Garamond', serif;
  min-height: 100vh;
  height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  position: relative;
  touch-action: manipulation;
  -webkit-tap-highlight-color: transparent;
}

.viewport-container {
  width: 100%;
  height: 100%;
  display: flex;
  flex-direction: column;
  opacity: 0;
  transition: opacity 0.6s ease;
}

@media (min-aspect-ratio: 9/16) {
  .viewport-container {
    width: auto;
    height: 100vh;
    aspect-ratio: 9 / 16;
    box-shadow: 0 0 40px rgba(0,0,0,0.1);
  }
}

.options-area {
  flex: 0 0 60%;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 1.5rem;
  position: relative;
  background-color: var(--paper);
}

@media (min-aspect-ratio: 9/16) {
  .options-area { padding: 4rem; }
}

@media (max-aspect-ratio: 9/16) {
  .options-area { padding: 2.8rem; }
}

.options-grid {
  width: 100%;
  max-width: 600px;
  display: grid;
  gap: 3.5rem;
  opacity: 0;
  animation: fadeIn 1.2s ease forwards 0.3s;
}

.options-grid.count-1 { grid-template-columns: 1fr; max-width: 33%; }
.options-grid.count-2 { grid-template-columns: 1fr 1fr; max-width: 400px; }
.options-grid.count-3 { grid-template-columns: repeat(3, 1fr); }
.options-grid.count-4 { 
  grid-template-columns: repeat(3, 1fr);
  grid-template-rows: auto auto;
}
.options-grid.count-5 { 
  grid-template-columns: repeat(3, 1fr);
  grid-template-rows: auto auto;
}

.option-btn {
  background: var(--offwhite);
  border: 2px solid var(--faint);
  border-radius: 8px;
  font-family: 'Zen Old Mincho', serif;
  font-size: 3rem;
  color: var(--ink);
  cursor: pointer;
  transition: all 0.2s ease;
  box-shadow: 0 2px 8px rgba(0,0,0,0.06);
  aspect-ratio: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  user-select: none;
  -webkit-user-select: none;
}

.option-btn:active {
  transform: scale(0.96);
  box-shadow: 0 1px 4px rgba(0,0,0,0.08);
}

.option-btn.correct {
  background: #e8f5e3;
  border-color: #7fb574;
  animation: pulse 0.4s ease;
}

.option-btn.incorrect {
  background: #f8d7da;
  border-color: #dc3545;
  animation: shake 0.4s ease;
}



.options-grid.count-4 .option-btn:nth-child(1) { grid-column: 2; }
.options-grid.count-4 .option-btn:nth-child(2) { grid-column: 1; grid-row: 2; }
.options-grid.count-4 .option-btn:nth-child(3) { grid-column: 2; grid-row: 2; }
.options-grid.count-4 .option-btn:nth-child(4) { grid-column: 3; grid-row: 2; }

.options-grid.count-3-kana {
  grid-template-columns: repeat(3, 1fr);
  grid-template-rows: auto auto auto;
}

/* ya行: ya=center(row2,col2), yu=top(row1,col2), yo=bottom(row3,col2) */
.options-grid.count-3-kana.ya .option-btn:nth-child(1) { grid-column: 2; grid-row: 1; }
.options-grid.count-3-kana.ya .option-btn:nth-child(2) { grid-column: 2; grid-row: 2; }
.options-grid.count-3-kana.ya .option-btn:nth-child(3) { grid-column: 2; grid-row: 3; }

/* wa行: wa=center(row2,col2), wo=left(row2,col1), n=top(row1,col2) */
.options-grid.count-3-kana.wa .option-btn:nth-child(1) { grid-column: 2; grid-row: 2; }
.options-grid.count-3-kana.wa .option-btn:nth-child(2) { grid-column: 1; grid-row: 2; }
.options-grid.count-3-kana.wa .option-btn:nth-child(3) { grid-column: 2; grid-row: 1; }

.options-grid.count-5 .option-btn:nth-child(1) { grid-column: 2; }
.options-grid.count-5 .option-btn:nth-child(2) { grid-column: 1; grid-row: 2; }
.options-grid.count-5 .option-btn:nth-child(3) { grid-column: 2; grid-row: 2; }
.options-grid.count-5 .option-btn:nth-child(4) { grid-column: 3; grid-row: 2; }
.options-grid.count-5 .option-btn:nth-child(5) { grid-column: 2; grid-row: 3; }

.info-area {
  flex: 0 0 40%;
  background: var(--offwhite);
  border-top: 2px solid var(--faint);
  box-shadow: 0 -4px 20px rgba(0,0,0,0.08);
  display: flex;
  flex-direction: column;
  align-items: center;
  position: relative;
  overflow-y: auto;
  opacity: 0;
  animation: slideUp 1.4s ease forwards 0.4s;
  padding: 0 1.5rem;
}

.info-content {
  padding: 1.2rem 0 1.5rem;
  flex: 1;
  display: flex;
  flex-direction: column;
  width: 100%;
  max-width: 600px;
}

.card-index,
.task-indicator {
  position: absolute;
  right: 1.5rem;
  font-family: 'DM Mono', monospace;
  font-size: 0.6rem;
  letter-spacing: 0.12em;
  color: var(--faint);
  text-transform: uppercase;
}

.card-index { top: 1rem; }
.task-indicator { top: 2.1rem; }

.kanji-char.hidden {
  opacity: 0;
  pointer-events: none;
}

@keyframes blink-caret {
  0%, 100% { caret-color: var(--ink); }
  50% { caret-color: transparent; }
}

.kanji-input.active {
  opacity: 1;
  pointer-events: auto;
}

.kanji-input.incorrect {
  color: var(--vermillion);
  animation: shake 0.4s ease;
}

.kanji-row {
  display: flex;
  align-items: baseline;
  gap: 1.8rem;
}

.kanji-slot {
  flex: 1;
  min-width: 0;
  position: relative;
  height: 1.1em;
  font-size: 4rem;
  line-height: 1;
}

.kanji-char, .kanji-input {
  font-family: 'Zen Old Mincho', serif;
  font-size: inherit;
  line-height: 1;
  color: var(--ink);
}

.kanji-char {
  display: block;
  cursor: default;
  user-select: none;
  transition: opacity 0.25s ease;
}

.kanji-input {
  position: absolute;
  inset: 0;
  background: none;
  border: none;
  outline: none;
  padding: 0;
  margin: 0;
  width: 100%;
  caret-color: var(--ink);
  animation: blink-caret 2s step-end infinite;
  opacity: 0;
  pointer-events: none;
}

.speaker-btn {
  background: none;
  border: 1px solid var(--faint);
  border-radius: 50%;
  width: 1.8rem;
  height: 1.8rem;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  font-size: 0.7rem;
  color: var(--muted);
  transition: all 0.18s ease;
  flex-shrink: 0;
  margin-left: auto;
}

.speaker-btn:active { transform: scale(0.92); }

.divider {
  width: 100%;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--faint) 20%, var(--faint) 80%, transparent);
  margin-top: 1.2rem;
  margin-bottom: 1rem;
}

.label {
  font-family: 'DM Mono', monospace;
  font-size: 0.65rem;
  letter-spacing: 0.2em;
  color: var(--faint);
  text-transform: uppercase;
  margin-bottom: 0.3rem;
}

.block { margin-bottom: 0.8rem; }

.readings {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem 0.9rem;
  align-items: baseline;
}

.reading-group {
  display: flex;
  align-items: baseline;
  gap: 0.5rem;
  cursor: pointer;
}

.reading-group:hover .reading-pill { color: var(--muted); }

.reading-pill {
  font-family: 'Zen Old Mincho', serif;
  font-size: 1.4rem;
  color: var(--ink);
  letter-spacing: 0.04em;
  transition: color 0.15s ease;
}

.reading-romaji {
  font-family: 'DM Mono', monospace;
  font-size: 0.7rem;
  color: var(--muted);
  letter-spacing: 0.08em;
  font-weight: 300;
}

.meaning-text {
  font-family: 'Cormorant Garamond', serif;
  font-size: 1.4rem;
  font-weight: 300;
  color: var(--ink);
  font-style: italic;
}

/* About mode: smaller meaning text for longer prose */
.meaning-text.prose {
  white-space: pre-line;
}

.wiktionary-link {
  display: inline-block;
  margin-top: 0.6rem;
  padding: 0.4rem 0.8rem;
  font-family: 'DM Mono', monospace;
  font-size: 0.6rem;
  letter-spacing: 0.1em;
  color: var(--muted);
  text-decoration: none;
  border: 1px solid var(--faint);
  text-transform: uppercase;
  transition: all 0.2s ease;
  background: none;
  cursor: pointer;
}

.wiktionary-link:hover {
  border-color: var(--muted);
  color: var(--ink);
}

.wiktionary-link:active { transform: scale(0.95); }

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

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

@keyframes pulse {
  0%, 100% { transform: scale(1); }
  50% { transform: scale(1.05); }
}

@keyframes shake {
  0%, 100% { transform: translateX(0); }
  25% { transform: translateX(-8px); }
  75% { transform: translateX(8px); }
}

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

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

.mode-btn {
  background: var(--offwhite);
  border: 2px solid var(--faint);
  font-family: 'Zen Old Mincho', serif;
  font-size: 1.6rem;
  color: var(--muted);
  cursor: pointer;
  transition: all 0.2s ease;
  box-shadow: 0 2px 8px rgba(0,0,0,0.06);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 0.8rem 0.6rem;
  gap: 0.1rem;
  user-select: none;
  -webkit-user-select: none;
  line-height: 1.3;
  border-radius: 8px;
  min-width: 2.8rem;
  position: relative;
}

.mode-btn.n5-btn {
  font-family: 'Zen Old Mincho', serif;
  font-size: 1.4rem;
}

.mode-btn.selected {
  border-color: var(--ink);
  color: var(--ink);
}

.mode-btn:active { transform: scale(0.96); }

.btn-label {
  position: absolute;
  top: 0.2rem;
  left: 0;
  right: 0;
  text-align: center;
  font-family: 'DM Mono', monospace;
  font-size: 0.45rem;
  letter-spacing: 0.1em;
  color: var(--ink);
  text-transform: uppercase;
  pointer-events: none;
}

.mode-btn.selected .btn-label,
.next-btn .btn-label {
  color: var(--ink);
}

.options-grid.choice-menu {
  position: absolute;
  inset: 0;
  display: block;
  max-width: none;
  width: 100%;
  height: 100%;
}

.choice-menu .mode-btns {
  position: absolute;
  top: 2.5rem;
  right: 2.5rem;
  display: flex;
  flex-direction: row;
  align-items: flex-start;
  gap: 0.8rem;
}

.choice-menu .next-btn {
  position: absolute;
  bottom: 2.5rem;
  left: 2.5rem;
}

.next-btn {
  background: var(--offwhite);
  border: 2px solid var(--faint);
  font-family: 'Zen Old Mincho', serif;
  font-size: 3rem;
  color: var(--ink);
  cursor: pointer;
  transition: all 0.2s ease;
  box-shadow: 0 2px 8px rgba(0,0,0,0.06);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  user-select: none;
  -webkit-user-select: none;
  border-radius: 8px;
  width: 5rem;
  height: 5rem;
  position: relative;
}

.next-btn:active { transform: scale(0.96); }

.option-btn.fade-out-1 { animation: fadeOut 0.6s ease forwards; }
.option-btn.fade-out-2 { animation: fadeOut 0.6s ease forwards 0.1s; }
.option-btn.fade-out-3 { animation: fadeOut 0.6s ease forwards 0.2s; }
.option-btn.fade-out-4 { animation: fadeOut 0.6s ease forwards 0.3s; }
.option-btn.fade-out-5 { animation: fadeOut 0.6s ease forwards 0.4s; }

.option-btn.fade-in-1 { animation: fadeInDelayed 0.7s ease forwards; }
.option-btn.fade-in-2 { animation: fadeInDelayed 0.7s ease forwards 0.12s; }
.option-btn.fade-in-3 { animation: fadeInDelayed 0.7s ease forwards 0.24s; }
.option-btn.fade-in-4 { animation: fadeInDelayed 0.7s ease forwards 0.36s; }
.option-btn.fade-in-5 { animation: fadeInDelayed 0.7s ease forwards 0.48s; }

@media (max-aspect-ratio: 9/16) {
  .options-grid { gap: 2.8rem; }
  .option-btn { font-size: 3.2rem; }
}

@media (min-aspect-ratio: 9/16) {
  .options-grid { gap: 4rem; }
  .option-btn { font-size: 3.5rem; }
  .kanji-slot { font-size: 4.5rem; }
  .kanji-input { font-size: inherit; width: 100%; }
  .reading-pill { font-size: 1.6rem; }
  .reading-romaji { font-size: 0.75rem; }
  .meaning-text { font-size: 1.6rem; }
  .card-index, .task-indicator { font-size: 0.7rem; }
  .speaker-btn { width: 2.4rem; height: 2.4rem; font-size: 0.9rem; }
}