/* ================================================
   LINGUA PHRASES - STYLES
   Educational language learning game
   ================================================ */

/* === ROOT VARIABLES === */
:root {
  /* Colors */
  --primary: #667eea;
  --primary-dark: #5568d3;
  --primary-light: #8899ff;
  --success: #10b981;
  --error: #ef4444;
  --warning: #f59e0b;

  /* Backgrounds */
  --bg-main: #f8fafc;
  --bg-card: #ffffff;
  --bg-overlay: rgba(0, 0, 0, 0.5);

  /* Text */
  --text-primary: #1e293b;
  --text-secondary: #64748b;
  --text-light: #94a3b8;

  /* Borders */
  --border-color: #e2e8f0;
  --border-radius: 12px;
  --border-radius-lg: 16px;

  /* Shadows */
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.06);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.08);
  --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.12);

  /* Transitions */
  --transition-fast: 0.15s ease;
  --transition-normal: 0.3s ease;
  --transition-slow: 0.5s ease;

  /* Spacing */
  --spacing-xs: 8px;
  --spacing-sm: 12px;
  --spacing-md: 16px;
  --spacing-lg: 24px;
  --spacing-xl: 32px;
}

/* === RESET & BASE === */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
  background: var(--bg-main);
  color: var(--text-primary);
  line-height: 1.6;
  min-height: 100vh;
  overflow-x: hidden;
}

/* === LOADING SCREEN === */
.loading-screen {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: var(--bg-main);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  z-index: 9999;
}

.loader {
  width: 50px;
  height: 50px;
  border: 4px solid var(--border-color);
  border-top-color: var(--primary);
  border-radius: 50%;
  animation: spin 1s linear infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

.loading-screen p {
  margin-top: var(--spacing-md);
  color: var(--text-secondary);
  font-size: 1rem;
}

/* === CONTAINER === */
.container {
  max-width: 800px;
  margin: 0 auto;
  padding: var(--spacing-lg);
  min-height: 100vh;
}

/* === HEADER === */
.game-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: var(--spacing-xl);
  padding-bottom: var(--spacing-md);
  border-bottom: 2px solid var(--border-color);
}

.game-title {
  font-size: 1.75rem;
  font-weight: 800;
  color: var(--text-primary);
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
}

.game-title .emoji {
  font-size: 2rem;
}

.btn-icon {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  border: 2px solid var(--border-color);
  background: var(--bg-card);
  color: var(--text-primary);
  font-size: 1.25rem;
  cursor: pointer;
  transition: all var(--transition-normal);
  display: flex;
  align-items: center;
  justify-content: center;
}

.btn-icon:hover {
  transform: scale(1.1);
  border-color: var(--primary);
  box-shadow: var(--shadow-md);
}

.btn-icon:focus-visible {
  outline: 3px solid var(--primary);
  outline-offset: 2px;
}

/* === SCREENS === */
.screen {
  display: none;
  animation: fadeIn var(--transition-normal);
}

.screen.active {
  display: block;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}

/* === LANGUAGE SELECTION === */
.language-selection {
  text-align: center;
}

.language-selection h2 {
  font-size: 2rem;
  margin-bottom: var(--spacing-sm);
  color: var(--text-primary);
}

.subtitle {
  color: var(--text-secondary);
  margin-bottom: var(--spacing-xl);
}

.language-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
  gap: var(--spacing-md);
  margin-bottom: var(--spacing-xl);
}

.language-card {
  background: var(--bg-card);
  border: 2px solid var(--border-color);
  border-radius: var(--border-radius-lg);
  padding: var(--spacing-lg);
  cursor: pointer;
  transition: all var(--transition-normal);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--spacing-sm);
  min-height: 140px;
}

.language-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-color: var(--primary);
}

.language-card:focus-visible {
  outline: 3px solid var(--primary);
  outline-offset: 2px;
}

.language-card .flag {
  font-size: 3rem;
}

.language-card .lang-name {
  font-size: 1.125rem;
  font-weight: 700;
  color: var(--text-primary);
}

.language-card .card-count {
  font-size: 0.875rem;
  color: var(--text-secondary);
}

/* === BEST SCORES === */
.best-scores {
  background: linear-gradient(135deg, var(--primary-light) 0%, var(--primary) 100%);
  padding: var(--spacing-lg);
  border-radius: var(--border-radius-lg);
  margin-top: var(--spacing-xl);
}

.best-scores h3 {
  color: white;
  margin-bottom: var(--spacing-md);
  font-size: 1.25rem;
}

.scores-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(100px, 1fr));
  gap: var(--spacing-sm);
}

.score-badge {
  background: rgba(255, 255, 255, 0.2);
  backdrop-filter: blur(10px);
  padding: var(--spacing-sm);
  border-radius: var(--border-radius);
  color: white;
  text-align: center;
}

.score-badge .flag {
  font-size: 1.5rem;
  display: block;
  margin-bottom: 4px;
}

.score-badge .percentage {
  font-size: 1.125rem;
  font-weight: 700;
}

/* === PROGRESS BAR === */
.progress-container {
  margin-bottom: var(--spacing-lg);
}

.progress-info {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: var(--spacing-sm);
  font-size: 0.875rem;
  color: var(--text-secondary);
  font-weight: 600;
}

.progress-bar {
  width: 100%;
  height: 8px;
  background: var(--border-color);
  border-radius: 999px;
  overflow: hidden;
}

.progress-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--primary) 0%, var(--primary-light) 100%);
  transition: width var(--transition-normal);
  border-radius: 999px;
}

/* === SCORE DISPLAY === */
.score-display {
  display: flex;
  justify-content: space-around;
  margin-bottom: var(--spacing-lg);
  padding: var(--spacing-md);
  background: var(--bg-card);
  border-radius: var(--border-radius);
  box-shadow: var(--shadow-sm);
}

.score-item {
  text-align: center;
}

.score-label {
  display: block;
  font-size: 0.875rem;
  color: var(--text-secondary);
  margin-bottom: 4px;
}

.score-value {
  display: block;
  font-size: 1.5rem;
  font-weight: 800;
  color: var(--primary);
}

/* === AUDIO CARD === */
.audio-card {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  padding: var(--spacing-xl);
  border-radius: var(--border-radius-lg);
  margin-bottom: var(--spacing-lg);
  color: white;
  box-shadow: var(--shadow-lg);
}

.audio-instructions {
  text-align: center;
  margin-bottom: var(--spacing-lg);
  font-size: 1rem;
  font-weight: 500;
}

.audio-controls {
  display: flex;
  gap: var(--spacing-md);
  justify-content: center;
  margin-bottom: var(--spacing-lg);
}

.btn-audio {
  padding: var(--spacing-md) var(--spacing-lg);
  border-radius: var(--border-radius);
  border: 2px solid rgba(255, 255, 255, 0.3);
  background: rgba(255, 255, 255, 0.2);
  backdrop-filter: blur(10px);
  color: white;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition-normal);
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
}

.btn-audio:hover:not(:disabled) {
  transform: scale(1.05);
  background: rgba(255, 255, 255, 0.3);
}

.btn-audio:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.btn-audio:focus-visible {
  outline: 3px solid white;
  outline-offset: 2px;
}

.btn-audio.btn-secondary {
  background: rgba(0, 0, 0, 0.1);
}

.audio-visual {
  display: flex;
  justify-content: center;
  align-items: center;
  height: 60px;
}

.waveform {
  display: flex;
  gap: 4px;
  align-items: center;
}

.waveform-bar {
  width: 4px;
  height: 20px;
  background: rgba(255, 255, 255, 0.6);
  border-radius: 2px;
  animation: wave 1.2s ease-in-out infinite;
}

@keyframes wave {
  0%, 100% { height: 20px; }
  50% { height: 40px; }
}

/* === CHOICES === */
.choices-container {
  margin-bottom: var(--spacing-lg);
}

.choices {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--spacing-md);
}

.choice {
  background: var(--bg-card);
  border: 3px solid var(--border-color);
  border-radius: var(--border-radius);
  padding: var(--spacing-lg);
  cursor: pointer;
  transition: all var(--transition-normal);
  text-align: left;
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
  min-height: 80px;
}

.choice:hover:not(.disabled) {
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
  border-color: var(--primary);
}

.choice:focus-visible {
  outline: 3px solid var(--primary);
  outline-offset: 2px;
}

.choice.disabled {
  cursor: not-allowed;
  opacity: 0.6;
}

.choice.correct {
  background: #d1fae5;
  border-color: var(--success);
  animation: correctPulse 0.5s ease;
}

.choice.incorrect {
  background: #fee2e2;
  border-color: var(--error);
  animation: shake 0.4s ease;
}

@keyframes correctPulse {
  0%, 100% { transform: scale(1); }
  50% { transform: scale(1.02); }
}

@keyframes shake {
  0%, 100% { transform: translateX(0); }
  25% { transform: translateX(-10px); }
  75% { transform: translateX(10px); }
}

.choice .letter {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: var(--primary);
  color: white;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  flex-shrink: 0;
}

.choice .text {
  font-size: 1.125rem;
  font-weight: 600;
  color: var(--text-primary);
}

/* === FEEDBACK === */
.feedback {
  background: var(--bg-card);
  border-radius: var(--border-radius);
  padding: var(--spacing-lg);
  margin-bottom: var(--spacing-lg);
  border-left: 4px solid transparent;
  min-height: 80px;
  display: flex;
  align-items: center;
  opacity: 0;
  transform: translateY(-10px);
  transition: all var(--transition-normal);
}

.feedback.show {
  opacity: 1;
  transform: translateY(0);
}

.feedback.correct {
  background: #d1fae5;
  border-left-color: var(--success);
}

.feedback.incorrect {
  background: #fee2e2;
  border-left-color: var(--error);
}

.feedback-content {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
  width: 100%;
}

.feedback-icon {
  font-size: 2rem;
  flex-shrink: 0;
}

.feedback-message {
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-primary);
}

/* === BUTTONS === */
.btn-primary,
.btn-secondary {
  border: none;
  border-radius: var(--border-radius);
  padding: var(--spacing-md) var(--spacing-xl);
  font-size: 1rem;
  font-weight: 700;
  cursor: pointer;
  transition: all var(--transition-normal);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-sm);
}

.btn-primary {
  background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
  color: white;
  box-shadow: var(--shadow-md);
}

.btn-primary:hover:not(:disabled) {
  transform: scale(1.02);
  box-shadow: var(--shadow-lg);
}

.btn-primary:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.btn-secondary {
  background: white;
  color: var(--primary);
  border: 2px solid var(--primary);
}

.btn-secondary:hover {
  background: var(--primary);
  color: white;
}

.btn-large {
  padding: var(--spacing-lg) var(--spacing-xl);
  font-size: 1.125rem;
  min-width: 200px;
}

.btn-primary:focus-visible,
.btn-secondary:focus-visible {
  outline: 3px solid var(--primary);
  outline-offset: 2px;
}

#next-btn {
  width: 100%;
}

/* === RESULTS === */
.results-container {
  text-align: center;
  padding: var(--spacing-xl);
}

.results-icon {
  font-size: 5rem;
  margin-bottom: var(--spacing-lg);
  animation: bounceIn 0.6s ease;
}

@keyframes bounceIn {
  0% { transform: scale(0); opacity: 0; }
  50% { transform: scale(1.1); }
  100% { transform: scale(1); opacity: 1; }
}

#results-title {
  font-size: 2rem;
  margin-bottom: var(--spacing-xl);
  color: var(--text-primary);
}

.results-stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: var(--spacing-lg);
  margin-bottom: var(--spacing-xl);
}

.stat-card {
  background: var(--bg-card);
  padding: var(--spacing-lg);
  border-radius: var(--border-radius-lg);
  box-shadow: var(--shadow-md);
}

.stat-value {
  display: block;
  font-size: 2.5rem;
  font-weight: 800;
  color: var(--primary);
  margin-bottom: var(--spacing-sm);
}

.stat-label {
  display: block;
  font-size: 0.875rem;
  color: var(--text-secondary);
  font-weight: 600;
}

.results-message {
  font-size: 1.125rem;
  color: var(--text-secondary);
  margin-bottom: var(--spacing-xl);
  line-height: 1.6;
}

.results-actions {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-md);
  align-items: center;
}

/* === RESPONSIVE === */
@media (max-width: 640px) {
  .container {
    padding: var(--spacing-md);
  }

  .game-title {
    font-size: 1.5rem;
  }

  .language-grid {
    grid-template-columns: repeat(auto-fill, minmax(120px, 1fr));
  }

  .choices {
    grid-template-columns: 1fr;
  }

  .score-display {
    flex-direction: column;
    gap: var(--spacing-md);
  }

  .results-stats {
    grid-template-columns: 1fr;
  }
}

/* === ACCESSIBILITY === */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

/* === UTILITIES === */
.hidden {
  display: none !important;
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border-width: 0;
}