/* === Korean Practice — Sentence Builder === */

:root {
  --primary: #6C5CE7;
  --primary-light: #A29BFE;
  --accent: #00B894;
  --bg: #F8F9FA;
  --card-bg: #FFFFFF;
  --text: #2D3436;
  --text-light: #636E72;
  --border: #DFE6E9;
  --shadow: 0 2px 8px rgba(0,0,0,0.08);
  --radius: 12px;

  --block-subject: #6C5CE7;
  --block-time: #FDCB6E;
  --block-place: #00B894;
  --block-object: #E17055;
  --block-verb: #0984E3;
  --block-adverb: #E84393;
  --block-adjective: #00CEC9;
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  background: var(--bg);
  color: var(--text);
  min-height: 100vh;
}

.container {
  max-width: 700px;
  margin: 0 auto;
  padding: 20px;
}

/* --- Index Page --- */
.index-page { text-align: center; padding-top: 60px; }

.app-header h1 {
  font-size: 1.8rem;
  margin-bottom: 8px;
}

.student-name { color: var(--primary); }

.subtitle {
  color: var(--text-light);
  font-size: 1rem;
  margin-bottom: 40px;
}

.pattern-cards {
  display: flex;
  flex-direction: column;
  gap: 20px;
  max-width: 400px;
  margin: 0 auto;
}

.pattern-card {
  display: block;
  background: var(--card-bg);
  border-radius: var(--radius);
  padding: 28px 24px;
  text-decoration: none;
  color: var(--text);
  box-shadow: var(--shadow);
  border: 2px solid transparent;
  transition: transform 0.15s, border-color 0.15s;
}

.pattern-card:hover {
  transform: translateY(-2px);
  border-color: var(--primary-light);
}

.card-icon { font-size: 2.5rem; display: block; margin-bottom: 12px; }

.pattern-card h2 { font-size: 1.3rem; margin-bottom: 8px; }

.card-desc { color: var(--text-light); font-size: 0.9rem; margin-bottom: 12px; }

.card-example {
  background: var(--bg);
  padding: 8px 14px;
  border-radius: 8px;
  font-size: 1rem;
  color: var(--primary);
}

.app-footer {
  margin-top: 40px;
  color: var(--text-light);
  font-size: 0.85rem;
}

/* --- Builder Pages --- */
.page-header {
  display: flex;
  align-items: center;
  gap: 16px;
  margin-bottom: 16px;
}

.page-header h1 { font-size: 1.4rem; }

.back-btn {
  text-decoration: none;
  color: var(--primary);
  font-weight: 600;
  font-size: 0.95rem;
}

.instruction {
  color: var(--text-light);
  font-size: 0.9rem;
  margin-bottom: 24px;
  text-align: center;
}

/* --- Sentence Blocks --- */
.sentence-area {
  background: var(--card-bg);
  border-radius: var(--radius);
  padding: 24px 16px;
  box-shadow: var(--shadow);
  margin-bottom: 20px;
}

.block-row {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  justify-content: center;
}

.block {
  flex: 1;
  min-width: 80px;
  max-width: 140px;
  padding: 14px 8px;
  border-radius: 10px;
  text-align: center;
  cursor: pointer;
  user-select: none;
  transition: transform 0.12s, box-shadow 0.12s;
  border: 2px solid transparent;
}

.block:active { transform: scale(0.95); }

.block:hover {
  box-shadow: 0 4px 12px rgba(0,0,0,0.15);
}

.block[data-slot="subject"] { background: var(--block-subject); color: #fff; }
.block[data-slot="time"] { background: var(--block-time); color: var(--text); }
.block[data-slot="place"] { background: var(--block-place); color: #fff; }
.block[data-slot="object"] { background: var(--block-object); color: #fff; }
.block[data-slot="verb"] { background: var(--block-verb); color: #fff; }
.block[data-slot="adverb"] { background: var(--block-adverb); color: #fff; }
.block[data-slot="adjective"] { background: var(--block-adjective); color: #fff; }

.block-kr {
  display: block;
  font-size: 1.2rem;
  font-weight: 700;
  margin-bottom: 4px;
}

.block-rom {
  display: block;
  font-size: 0.65rem;
  opacity: 0.85;
  margin-bottom: 2px;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.block-en {
  display: block;
  font-size: 0.7rem;
  opacity: 0.8;
}

.block.pulse {
  animation: pulse 0.3s ease;
}

@keyframes pulse {
  0% { transform: scale(1); }
  50% { transform: scale(1.08); }
  100% { transform: scale(1); }
}

/* --- Result Area --- */
.result-area {
  text-align: center;
  padding: 20px;
  background: var(--card-bg);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  margin-bottom: 16px;
}

.full-sentence {
  font-size: 1.5rem;
  font-weight: 700;
  margin-bottom: 8px;
  color: var(--text);
  min-height: 2rem;
}

.translation {
  font-size: 0.95rem;
  color: var(--text-light);
  margin-bottom: 16px;
  min-height: 1.4rem;
}

.tts-btn-large {
  background: var(--primary);
  color: #fff;
  border: none;
  padding: 10px 24px;
  border-radius: 8px;
  font-size: 1rem;
  cursor: pointer;
  transition: background 0.15s;
}

.tts-btn-large:hover { background: var(--primary-light); }
.tts-btn-large:active { transform: scale(0.97); }

/* --- Slot Labels --- */
.slot-labels {
  display: flex;
  justify-content: center;
  gap: 8px;
  flex-wrap: wrap;
}

.slot-labels span {
  flex: 1;
  min-width: 80px;
  max-width: 140px;
  text-align: center;
  font-size: 0.7rem;
  color: var(--text-light);
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

/* --- Element Toggle Buttons (Action Builder) --- */
.element-toggles {
  display: flex;
  gap: 8px;
  justify-content: center;
  margin-bottom: 16px;
  flex-wrap: wrap;
}

.element-toggle {
  background: var(--bg-card);
  color: var(--text-light);
  border: 2px solid var(--text-light);
  padding: 6px 16px;
  border-radius: 20px;
  font-size: 0.82rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s;
}

.element-toggle:hover {
  background: rgba(107, 114, 128, 0.1);
}

.element-toggle.active {
  background: var(--primary);
  color: #fff;
  border-color: var(--primary);
}

.element-toggle:disabled {
  opacity: 0.4;
  cursor: not-allowed;
}

/* --- Adverb Toggle --- */
.adverb-toggle {
  text-align: center;
  margin-bottom: 16px;
}

.btn-adverb {
  background: var(--block-adverb);
  color: #fff;
  border: none;
  padding: 8px 20px;
  border-radius: 8px;
  font-size: 0.9rem;
  cursor: pointer;
  transition: opacity 0.15s;
}

.btn-adverb:hover { opacity: 0.85; }
.btn-adverb.active { background: var(--text-light); }

/* --- Romanization Toggle --- */
.rom-toggle {
  text-align: center;
  margin-bottom: 16px;
}

.btn-rom {
  background: var(--card-bg);
  color: var(--text);
  border: 2px solid var(--border);
  padding: 6px 16px;
  border-radius: 8px;
  font-size: 0.85rem;
  cursor: pointer;
  transition: border-color 0.15s, background 0.15s;
}

.btn-rom:hover { border-color: var(--primary-light); }
.btn-rom.active { background: var(--primary); color: #fff; border-color: var(--primary); }

body.hide-rom .block-rom { display: none !important; }
body.hide-rom .card-romanization { display: none !important; }
body.hide-en .block-en { display: none !important; }
body.hide-en .card-english { display: none !important; }
body.hide-en .translation { display: none !important; }

/* --- Flashcard Page --- */
.category-tabs {
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
  justify-content: center;
  margin-bottom: 20px;
}

.cat-tab {
  background: var(--card-bg);
  border: 2px solid var(--border);
  padding: 6px 14px;
  border-radius: 20px;
  font-size: 0.75rem;
  cursor: pointer;
  transition: all 0.15s;
}

.cat-tab:hover { border-color: var(--primary-light); }
.cat-tab.active { background: var(--primary); color: #fff; border-color: var(--primary); }

.flashcard-area {
  display: flex;
  justify-content: center;
  margin-bottom: 20px;
  perspective: 1000px;
}

.flashcard {
  width: 300px;
  height: 200px;
  cursor: pointer;
  perspective: 1000px;
}

.flashcard-inner {
  width: 100%;
  height: 100%;
  position: relative;
  transition: transform 0.5s;
  transform-style: preserve-3d;
}

.flashcard-inner.flipped {
  transform: rotateY(180deg);
}

.flashcard-front, .flashcard-back {
  position: absolute;
  width: 100%;
  height: 100%;
  backface-visibility: hidden;
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 20px;
}

.flashcard-front {
  background: var(--primary);
  color: #fff;
}

.flashcard-back {
  background: var(--card-bg);
  color: var(--text);
  transform: rotateY(180deg);
}

.card-korean {
  font-size: 2.2rem;
  font-weight: 700;
}

.card-english {
  font-size: 1.3rem;
  font-weight: 600;
  margin-bottom: 8px;
}

.card-romanization {
  font-size: 0.9rem;
  color: var(--text-light);
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.tts-btn {
  background: rgba(255,255,255,0.2);
  border: none;
  padding: 8px 16px;
  border-radius: 8px;
  font-size: 1.2rem;
  cursor: pointer;
  position: absolute;
  bottom: 12px;
  right: 12px;
  transition: background 0.15s;
}

.tts-btn:hover { background: rgba(255,255,255,0.3); }

.flashcard-controls {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 24px;
  margin-bottom: 16px;
}

.fc-btn {
  background: var(--card-bg);
  border: 2px solid var(--border);
  width: 48px;
  height: 48px;
  border-radius: 50%;
  font-size: 1.2rem;
  cursor: pointer;
  transition: all 0.15s;
  display: flex;
  align-items: center;
  justify-content: center;
}

.fc-btn:hover { border-color: var(--primary); background: var(--primary); color: #fff; }

.fc-progress {
  font-size: 1rem;
  color: var(--text-light);
  font-weight: 600;
  min-width: 80px;
  text-align: center;
}

.flashcard-actions {
  display: flex;
  gap: 12px;
  justify-content: center;
  margin-bottom: 16px;
}

.fc-action-btn {
  background: var(--card-bg);
  border: 2px solid var(--border);
  padding: 8px 16px;
  border-radius: 8px;
  font-size: 0.85rem;
  cursor: pointer;
  transition: all 0.15s;
}

.fc-action-btn:hover { border-color: var(--primary-light); }

/* --- Block TTS Button --- */
.block {
  position: relative;
}

.block-tts-btn {
  position: absolute;
  top: 4px;
  right: 4px;
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background: rgba(255,255,255,0.25);
  border: 1.5px solid rgba(255,255,255,0.4);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background 0.15s, transform 0.15s;
  padding: 0;
  z-index: 2;
}

.block-tts-btn:hover {
  background: rgba(255,255,255,0.45);
  transform: scale(1.15);
}

.block-tts-btn:active {
  transform: scale(0.9);
}

.block-tts-btn svg {
  width: 12px;
  height: 12px;
  fill: rgba(255,255,255,0.9);
}

/* Time block has dark text, adjust TTS button */
.block[data-slot="time"] .block-tts-btn {
  background: rgba(0,0,0,0.1);
  border-color: rgba(0,0,0,0.2);
}

.block[data-slot="time"] .block-tts-btn:hover {
  background: rgba(0,0,0,0.2);
}

.block[data-slot="time"] .block-tts-btn svg {
  fill: rgba(0,0,0,0.6);
}

/* --- Response Tracking Buttons --- */
.response-buttons {
  display: flex;
  gap: 10px;
  justify-content: center;
  margin-bottom: 16px;
}

.resp-btn {
  flex: 1;
  max-width: 120px;
  padding: 12px 8px;
  border-radius: 10px;
  font-size: 0.9rem;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.15s;
  border: 2px solid transparent;
}

.resp-know {
  background: #00B894;
  color: #fff;
  border-color: #00B894;
}

.resp-know:hover { background: #00a381; }

.resp-unsure {
  background: #FDCB6E;
  color: #2D3436;
  border-color: #FDCB6E;
}

.resp-unsure:hover { background: #f0be4a; }

.resp-dont-know {
  background: #E17055;
  color: #fff;
  border-color: #E17055;
}

.resp-dont-know:hover { background: #d05a40; }

.resp-btn.resp-used {
  transform: scale(0.92);
  opacity: 0.6;
}

/* --- Mastery Stats --- */
.mastery-stats {
  text-align: center;
  font-size: 0.8rem;
  color: var(--text-light);
  margin-bottom: 12px;
  letter-spacing: 0.5px;
}

.mastery-stats .stat-know { color: #00B894; font-weight: 600; }
.mastery-stats .stat-unsure { color: #FDCB6E; font-weight: 600; }
.mastery-stats .stat-dont-know { color: #E17055; font-weight: 600; }

/* --- Card Status Badge --- */
.card-badge {
  position: absolute;
  top: 8px;
  left: 8px;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  z-index: 2;
}

.card-badge.know { background: #00B894; }
.card-badge.unsure { background: #FDCB6E; }
.card-badge.dont-know { background: #E17055; }

/* --- Review Banner --- */
.review-banner {
  text-align: center;
  background: var(--primary);
  color: #fff;
  padding: 8px;
  border-radius: 8px;
  margin-bottom: 12px;
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 12px;
  font-size: 0.85rem;
  font-weight: 600;
}

.review-exit-btn {
  background: rgba(255,255,255,0.2);
  border: none;
  color: #fff;
  padding: 4px 12px;
  border-radius: 6px;
  cursor: pointer;
  font-size: 0.8rem;
  transition: background 0.15s;
}

.review-exit-btn:hover { background: rgba(255,255,255,0.35); }

/* --- Utilities --- */
.hidden { display: none !important; }

/* --- Responsive --- */
@media (max-width: 500px) {
  .block {
    min-width: 60px;
    max-width: 110px;
    padding: 10px 6px;
  }
  .block-kr { font-size: 1rem; }
  .full-sentence { font-size: 1.25rem; }
  .index-page { padding-top: 30px; }
  .app-header h1 { font-size: 1.5rem; }
  .flashcard { width: 260px; height: 180px; }
  .card-korean { font-size: 1.8rem; }
  .cat-tab { padding: 4px 10px; font-size: 0.7rem; }
}