/* ============================================
   Gamified Learning System CSS
   ============================================ */

/* 1. Stats Bar (#learn-stats) */
#learn-stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
  padding: 24px;
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  position: relative;
}

#learn-stats::before {
  content: '';
  position: absolute;
  inset: -1px;
  border-radius: var(--radius-lg);
  padding: 1px;
  background: linear-gradient(135deg, var(--accent), var(--border), var(--accent-muted));
  -webkit-mask:
    linear-gradient(#fff 0 0) content-box,
    linear-gradient(#fff 0 0);
  mask:
    linear-gradient(#fff 0 0) content-box,
    linear-gradient(#fff 0 0);
  -webkit-mask-composite: xor;
  mask-composite: exclude;
  pointer-events: none;
}

.stat-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
  padding: 16px 12px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  transition: background 0.2s, border-color 0.2s;
}

.stat-card:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-light);
}

.stat-card .icon {
  font-size: 20px;
  line-height: 1;
}

.stat-card .value {
  font-family: var(--font-sans);
  font-size: 24px;
  font-weight: 700;
  color: var(--text-primary);
}

.stat-card .label {
  font-family: var(--font-sans);
  font-size: 12px;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.stat-card.xp .value {
  color: var(--accent);
}

@keyframes xpPulse {
  0%, 100% { box-shadow: 0 0 0 0 var(--accent-glow); }
  50% { box-shadow: 0 0 12px 4px var(--accent-glow); }
}

.stat-card.xp {
  animation: xpPulse 3s ease-in-out infinite;
}

@media (max-width: 640px) {
  #learn-stats {
    grid-template-columns: repeat(2, 1fr);
  }
}

/* 2. Progress Bars (per language) */
.progress-bar-container {
  display: flex;
  align-items: center;
  gap: 10px;
  padding-top: 12px;
}

.progress-bar-track {
  flex: 1;
  height: 4px;
  background: var(--bg-tertiary);
  border-radius: 2px;
  overflow: hidden;
}

.progress-bar-fill {
  height: 100%;
  border-radius: 2px;
  background: linear-gradient(90deg, var(--accent), #60a5fa);
  transition: width 0.6s cubic-bezier(0.22, 1, 0.36, 1);
}

.progress-bar-fill.completed {
  background: linear-gradient(90deg, var(--green), #6ee7b7);
}

.progress-bar-label {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--text-secondary);
  white-space: nowrap;
}

/* 3. XP Floating Popup (.xp-float) */
.xp-float {
  position: absolute;
  left: 50%;
  top: -10px;
  transform: translateX(-50%);
  font-family: var(--font-sans);
  font-size: 16px;
  font-weight: 700;
  color: var(--green);
  text-shadow: 0 0 10px rgba(52, 211, 153, 0.6);
  pointer-events: none;
  z-index: 100;
  animation: xpFloat 1.2s ease-out forwards;
}

@keyframes xpFloat {
  0% {
    opacity: 1;
    transform: translateX(-50%) translateY(0);
  }
  100% {
    opacity: 0;
    transform: translateX(-50%) translateY(-60px);
  }
}

/* 4. Achievement Toast (.achievement-toast) */
.achievement-toast {
  position: fixed;
  bottom: 24px;
  right: 24px;
  width: 320px;
  padding: 16px;
  background: var(--bg-card);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--accent);
  border-radius: var(--radius-lg);
  box-shadow:
    0 0 20px var(--accent-glow),
    0 8px 32px rgba(0, 0, 0, 0.4);
  z-index: 1000;
  animation: toastIn 0.4s cubic-bezier(0.22, 1, 0.36, 1) forwards;
}

.achievement-toast.removing {
  animation: toastOut 0.4s cubic-bezier(0.55, 0, 1, 0.45) forwards;
}

@keyframes toastIn {
  0% {
    opacity: 0;
    transform: translateX(100%) translateY(10px);
  }
  100% {
    opacity: 1;
    transform: translateX(0) translateY(0);
  }
}

@keyframes toastOut {
  0% {
    opacity: 1;
    transform: translateX(0);
  }
  100% {
    opacity: 0;
    transform: translateX(120%);
  }
}

.achievement-toast .toast-icon {
  font-size: 28px;
  line-height: 1;
  margin-bottom: 8px;
}

.achievement-toast .toast-title {
  font-family: var(--font-sans);
  font-size: 14px;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 4px;
}

.achievement-toast .toast-description {
  font-family: var(--font-sans);
  font-size: 12px;
  color: var(--text-muted);
  line-height: 1.4;
}

/* 5. Confetti Particles (.confetti-particle) */
.confetti-particle {
  position: absolute;
  width: 6px;
  height: 6px;
  border-radius: 2px;
  pointer-events: none;
  z-index: 999;
  animation: confettiFall 1.8s ease-in forwards;
}

.confetti-particle:nth-child(odd) {
  width: 8px;
  height: 8px;
  border-radius: 1px;
}

@keyframes confettiFall {
  0% {
    opacity: 1;
    transform: translateY(0) rotate(0deg) scale(1);
  }
  100% {
    opacity: 0;
    transform: translateY(120vh) rotate(720deg) scale(0.5);
  }
}

/* 6. Streak Counter (.streak-badge) */
.streak-badge {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 2px 10px;
  font-family: var(--font-sans);
  font-size: 12px;
  font-weight: 700;
  color: var(--orange);
  background: var(--orange-muted);
  border-radius: 999px;
  line-height: 1.6;
}

@keyframes streakPulse {
  0%, 100% { transform: scale(1); }
  50% { transform: scale(1.15); }
}

.streak-badge.pulse {
  animation: streakPulse 0.4s ease-in-out;
}

/* 7. Achievement Badge (.achievement-card) */
.achievement-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  padding: 20px 16px;
  background: var(--bg-card);
  border: 1px solid var(--accent);
  border-radius: var(--radius-lg);
  text-align: center;
  transition:
    transform 0.2s,
    box-shadow 0.2s,
    border-color 0.2s;
}

.achievement-card:hover {
  transform: translateY(-3px);
  box-shadow: 0 6px 20px var(--accent-glow);
  border-color: var(--accent-hover);
}

.achievement-card .ach-icon {
  font-size: 32px;
  line-height: 1;
}

.achievement-card .ach-name {
  font-family: var(--font-sans);
  font-size: 14px;
  font-weight: 700;
  color: var(--text-primary);
}

.achievement-card .ach-description {
  font-family: var(--font-sans);
  font-size: 12px;
  color: var(--text-muted);
  line-height: 1.4;
}

.achievement-card.locked {
  opacity: 0.4;
  filter: grayscale(1);
  border-style: dashed;
}

.achievement-card.locked:hover {
  transform: none;
  box-shadow: none;
  border-color: var(--border);
}

/* 8. Completion Celebration (.lesson-complete-banner) */
.lesson-complete-banner {
  width: 100%;
  padding: 24px;
  background: linear-gradient(135deg, var(--accent), var(--green));
  color: #fff;
  text-align: center;
  font-family: var(--font-sans);
  border-radius: var(--radius-lg);
  animation: bannerFade 3s ease-in-out forwards;
}

.lesson-complete-banner .banner-check {
  font-size: 28px;
  display: inline-block;
  animation: checkPop 0.5s ease-out;
}

.lesson-complete-banner .banner-text {
  font-size: 18px;
  font-weight: 700;
  margin-top: 8px;
}

@keyframes bannerFade {
  0% { opacity: 0; transform: scaleY(0.8); }
  10% { opacity: 1; transform: scaleY(1); }
  80% { opacity: 1; transform: scaleY(1); }
  100% { opacity: 0; transform: scaleY(0.8); }
}

@keyframes checkPop {
  0% { transform: scale(0); }
  60% { transform: scale(1.3); }
  100% { transform: scale(1); }
}

/* 9. Animated Background (.learn-hero-bg) */
.learn-hero-bg {
  position: absolute;
  inset: 0;
  overflow: hidden;
  pointer-events: none;
  z-index: 0;
}

.learn-hero-bg::before {
  content: '';
  position: absolute;
  inset: -50%;
  width: 200%;
  height: 200%;
  background: linear-gradient(
    135deg,
    rgba(124, 92, 252, 0.08),
    rgba(20, 100, 100, 0.06),
    rgba(124, 92, 252, 0.04),
    rgba(30, 80, 120, 0.06)
  );
  background-size: 300% 300%;
  animation: gradientShift 12s ease-in-out infinite;
}

@keyframes gradientShift {
  0% { background-position: 0% 50%; }
  50% { background-position: 100% 50%; }
  100% { background-position: 0% 50%; }
}

/* 10. Score Display (.score-display) */
.score-display {
  font-family: var(--font-sans);
  font-size: 48px;
  font-weight: 700;
  color: var(--accent);
  text-align: center;
  text-shadow: 0 0 24px var(--accent-glow);
  animation: scorePulse 2.5s ease-in-out infinite;
}

@keyframes scorePulse {
  0%, 100% {
    text-shadow: 0 0 24px var(--accent-glow);
    transform: scale(1);
  }
  50% {
    text-shadow:
      0 0 32px var(--accent-glow),
      0 0 48px var(--accent-muted);
    transform: scale(1.02);
  }
}

/* Reduced Motion */
@media (prefers-reduced-motion: reduce) {
  * {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}