@import url('https://fonts.googleapis.com/css2?family=Nunito:wght@400;600;700;800&display=swap');

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

:root {
  --coral: #FF6B6B;
  --coral-dark: #e55a5a;
  --teal: #4ECDC4;
  --teal-dark: #3dbdb4;
  --cream: #FFF8F0;
  --warm-grey: #B8B0A8;
  --dark: #2D3436;
  --card-bg: #FFFFFF;
  --shadow: 0 4px 20px rgba(0,0,0,0.08);
  --radius: 20px;
}

body {
  font-family: 'Nunito', sans-serif;
  background: var(--cream);
  color: var(--dark);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 16px;
  -webkit-tap-highlight-color: transparent;
  user-select: none;
}

/* ---- Header ---- */
.header {
  width: 100%;
  max-width: 500px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 8px 0;
  margin-bottom: 12px;
}

.header h1 {
  font-size: 1.4rem;
  font-weight: 800;
  color: var(--coral);
}

.header-buttons {
  display: flex;
  gap: 4px;
}

.settings-btn {
  background: none;
  border: none;
  font-size: 1.6rem;
  cursor: pointer;
  padding: 8px;
  border-radius: 50%;
  transition: background 0.2s;
  line-height: 1;
}

.settings-btn:hover {
  background: rgba(0,0,0,0.05);
}

/* ---- Flashcard ---- */
.card-container {
  width: 100%;
  max-width: 500px;
  margin-bottom: 16px;
}

.flashcard {
  background: var(--card-bg);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 40px 32px;
  text-align: center;
  min-height: 140px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
}

.flashcard-word {
  font-size: 7rem;
  font-weight: 800;
  letter-spacing: 0.04em;
  line-height: 1.2;
}

/* ---- Emoji choices ---- */
.emoji-choices {
  width: 100%;
  max-width: 500px;
  display: flex;
  gap: 12px;
  margin-bottom: 16px;
  justify-content: center;
}

.emoji-btn {
  flex: 1;
  max-width: 150px;
  aspect-ratio: 1;
  font-size: 3.5rem;
  background: var(--card-bg);
  border: 3px solid #E8E0D8;
  border-radius: var(--radius);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: transform 0.12s ease, border-color 0.12s ease;
  box-shadow: 0 2px 8px rgba(0,0,0,0.05);
  position: relative;
  padding: 8px;
  overflow: hidden;
}

.emoji-btn img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: contain;
  pointer-events: none;
}

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

.emoji-btn.correct {
  border-color: var(--teal);
  background: #E8FFF8;
  animation: popCorrect 0.4s ease;
}

.emoji-btn.wrong {
  border-color: var(--coral);
  opacity: 0.4;
}

.emoji-btn.reveal {
  border-color: var(--teal);
  background: #E8FFF8;
}

.emoji-btn.disabled {
  pointer-events: none;
}

.emoji-tick {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 3rem;
  color: var(--teal);
  background: rgba(255,255,255,0.6);
  border-radius: var(--radius);
  animation: tickPop 0.5s ease;
  pointer-events: none;
}

@keyframes popCorrect {
  0% { transform: scale(1); }
  40% { transform: scale(1.12); }
  100% { transform: scale(1); }
}

/* ---- Feedback (tick / cross) ---- */
.feedback {
  width: 100%;
  max-width: 500px;
  text-align: center;
  min-height: 60px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 8px;
}

.feedback-tick {
  font-size: 3rem;
  color: var(--teal);
  animation: tickPop 0.5s ease;
}

.feedback-try-again {
  font-size: 1.1rem;
  color: var(--coral);
  font-weight: 700;
  animation: fadeInUp 0.3s ease;
}

@keyframes tickPop {
  0% { transform: scale(0); opacity: 0; }
  50% { transform: scale(1.3); }
  100% { transform: scale(1); opacity: 1; }
}

@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(12px); }
  to { opacity: 1; transform: translateY(0); }
}

/* ---- Button row ---- */
.btn-row {
  width: 100%;
  max-width: 500px;
  display: flex;
  gap: 10px;
  margin-bottom: 12px;
}

.next-btn {
  flex: 1;
  padding: 16px;
  font-size: 1.2rem;
  font-weight: 700;
  font-family: 'Nunito', sans-serif;
  background: var(--coral);
  color: white;
  border: none;
  border-radius: var(--radius);
  cursor: pointer;
  transition: background 0.2s, transform 0.1s;
}

.next-btn:hover {
  background: var(--coral-dark);
}

.next-btn:active {
  transform: scale(0.97);
}

/* ---- Session counter ---- */
.session-counter {
  font-size: 0.85rem;
  color: var(--warm-grey);
  font-weight: 600;
  margin-bottom: 12px;
  min-height: 1.2em;
}

/* ---- Progress bar ---- */
.progress-section {
  width: 100%;
  max-width: 500px;
  margin-bottom: 12px;
}

.progress-label {
  font-size: 0.8rem;
  color: var(--warm-grey);
  margin-bottom: 5px;
  font-weight: 600;
}

.progress-bar-track {
  width: 100%;
  height: 8px;
  background: #E8E0D8;
  border-radius: 4px;
  overflow: hidden;
}

.progress-bar-fill {
  height: 100%;
  background: var(--teal);
  border-radius: 4px;
  transition: width 0.4s ease;
}

/* ---- Mystery Picture ---- */
.mystery-section {
  width: 100%;
  max-width: 500px;
  margin-bottom: 16px;
}

.mystery-wrapper {
  position: relative;
  width: 100%;
  aspect-ratio: 1;
  border-radius: 16px;
  overflow: hidden;
  box-shadow: var(--shadow);
}

#mystery-canvas {
  display: block;
  width: 100%;
  height: 100%;
}

.mystery-overlay {
  position: absolute;
  inset: 0;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  grid-template-rows: repeat(4, 1fr);
}

.overlay-cell {
  background: #D4CBC0;
  transition: background 0.5s ease, opacity 0.5s ease;
  border: 1px solid #C8BFB4;
}

.overlay-cell.revealed {
  background: transparent;
  border-color: transparent;
  animation: cellReveal 0.5s ease forwards;
}

@keyframes cellReveal {
  0% { opacity: 1; }
  50% { opacity: 0.5; background: rgba(255,255,255,0.4); }
  100% { opacity: 0; }
}

/* ---- Empty state ---- */
.empty-state {
  text-align: center;
  padding: 40px 20px;
}

.empty-state p {
  font-size: 1.1rem;
  color: var(--warm-grey);
  margin-bottom: 12px;
}

/* ---- Celebration overlay ---- */
.celebration {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.5);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  z-index: 100;
  animation: fadeIn 0.3s ease;
  padding: 20px;
}

.celebration-content {
  background: var(--card-bg);
  border-radius: var(--radius);
  padding: 32px;
  text-align: center;
  max-width: 360px;
  width: 100%;
  animation: bounceIn 0.5s ease;
}

.celebration-canvas-wrap {
  width: 100%;
  aspect-ratio: 1;
  border-radius: 12px;
  overflow: hidden;
  margin-bottom: 16px;
}

.celebration-canvas-wrap canvas {
  width: 100%;
  height: 100%;
  display: block;
}

.celebration h2 {
  font-size: 1.5rem;
  color: var(--coral);
  margin-bottom: 8px;
}

.celebration p {
  color: var(--warm-grey);
  margin-bottom: 20px;
}

.celebration button {
  padding: 12px 32px;
  font-size: 1.1rem;
  font-weight: 700;
  font-family: 'Nunito', sans-serif;
  background: var(--teal);
  color: white;
  border: none;
  border-radius: var(--radius);
  cursor: pointer;
}

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

@keyframes bounceIn {
  0% { transform: scale(0.7); opacity: 0; }
  60% { transform: scale(1.05); }
  100% { transform: scale(1); opacity: 1; }
}

/* ---- Settings Panel ---- */
.settings-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.4);
  z-index: 50;
  animation: fadeIn 0.2s ease;
}

.settings-panel {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  max-height: 85vh;
  background: var(--card-bg);
  border-radius: 24px 24px 0 0;
  padding: 24px 20px;
  z-index: 51;
  overflow-y: auto;
  animation: slideUp 0.3s ease;
}

@keyframes slideUp {
  from { transform: translateY(100%); }
  to { transform: translateY(0); }
}

.settings-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 8px;
}

.settings-header h2 {
  font-size: 1.2rem;
  font-weight: 800;
}

.close-btn {
  background: none;
  border: none;
  font-size: 1.5rem;
  cursor: pointer;
  padding: 8px;
  line-height: 1;
  color: var(--warm-grey);
}

.word-count {
  font-size: 0.95rem;
  color: var(--teal);
  font-weight: 700;
  margin-bottom: 20px;
}

.sound-group {
  margin-bottom: 20px;
}

.sound-group-header {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 10px;
  cursor: pointer;
  padding: 4px 0;
}

.sound-group-header h3 {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--dark);
}

.group-toggle {
  font-size: 0.75rem;
  color: var(--teal);
  font-weight: 700;
  background: none;
  border: 1px solid var(--teal);
  border-radius: 8px;
  padding: 2px 8px;
  cursor: pointer;
  margin-left: auto;
}

.sound-chips {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.sound-chip {
  padding: 8px 14px;
  border-radius: 12px;
  font-size: 0.95rem;
  font-weight: 700;
  font-family: 'Nunito', sans-serif;
  cursor: pointer;
  transition: all 0.15s ease;
  border: 2px solid #D4CBC0;
  background: transparent;
  color: var(--warm-grey);
  min-width: 44px;
  min-height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.sound-chip.active {
  background: var(--teal);
  border-color: var(--teal);
  color: white;
}

.sound-chip:active {
  transform: scale(0.93);
}

/* ---- Layout ---- */
.main-layout {
  width: 100%;
  max-width: 500px;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.quiz-column {
  width: 100%;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.picture-column {
  width: 100%;
}

/* ---- Responsive ---- */
@media (max-width: 400px) {
  .flashcard-word {
    font-size: 5.6rem;
  }
  .flashcard {
    padding: 32px 24px;
    min-height: 120px;
  }
  .emoji-btn {
    font-size: 2.8rem;
  }
}

@media (min-width: 768px) {
  .header {
    max-width: 900px;
  }

  .main-layout {
    max-width: 900px;
    flex-direction: row;
    align-items: flex-start;
    gap: 40px;
  }

  .quiz-column {
    flex: 1;
    min-width: 0;
  }

  .card-container,
  .emoji-choices,
  .feedback,
  .btn-row,
  .progress-section,
  .mystery-section {
    max-width: none;
  }

  .picture-column {
    width: 320px;
    flex-shrink: 0;
    position: sticky;
    top: 16px;
  }

  .flashcard-word {
    font-size: 9rem;
  }
  .emoji-btn {
    font-size: 4.5rem;
  }
}