/* ══════════════════════════════════════
   THEME TOGGLE
   ══════════════════════════════════════ */
.theme-toggle {
  position: fixed;
  top: 20px;
  right: 20px;
  z-index: 100;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  border: 1px solid var(--border);
  background: var(--bg-card);
  box-shadow: var(--shadow-md);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 18px;
  line-height: 1;
  transition: all 0.2s var(--ease);
}
.theme-toggle .toggle-icon {
  display: flex;
  align-items: center;
  justify-content: center;
}
.theme-toggle iconify-icon {
  display: block;
}
.theme-toggle:hover { transform: scale(1.1); box-shadow: var(--shadow-lg); }
.theme-toggle:active { transform: scale(0.95); }
.dark .theme-toggle { color: var(--fg); }

/* ══════════════════════════════════════
   SCREEN SYSTEM
   ══════════════════════════════════════ */
.screen {
  display: none;
  max-width: 720px;
  margin: 0 auto;
  padding: 32px 24px 80px;
  min-height: 100vh;
}
.screen.active {
  display: block;
  animation: screenIn 0.4s var(--ease) both;
}
#landing.active,
#lesson-loader.active {
  animation: screenInFlex 0.4s var(--ease) both;
}
@keyframes screenInFlex {
  from { opacity: 0; transform: scale(0.97); filter: blur(4px); }
  to { opacity: 1; transform: scale(1); filter: blur(0); }
}
@keyframes screenIn {
  from { opacity: 0; transform: scale(0.97); filter: blur(4px); }
  to { opacity: 1; transform: scale(1); filter: blur(0); }
}

/* ══════════════════════════════════════
   SHARED COMPONENTS
   ══════════════════════════════════════ */

/* Buttons */
.btn {
  font-family: var(--font-body);
  font-weight: 600;
  font-size: 15px;
  padding: 11px 26px;
  border-radius: var(--radius-pill);
  border: 1.5px solid transparent;
  cursor: pointer;
  transition: all 0.2s var(--ease);
  display: inline-flex;
  align-items: center;
  gap: 8px;
  text-decoration: none;
}
.btn:active { transform: scale(0.96); }

.btn-primary {
  background: var(--primary-50);
  color: var(--primary-700);
  border-color: var(--primary-200);
}
.btn-primary:hover {
  background: var(--primary-100);
  border-color: var(--primary-300);
  box-shadow: 0 0 0 3px var(--ring);
}
.dark .btn-primary {
  background: var(--primary-100);
  color: var(--primary-700);
  border-color: var(--primary-200);
}
.dark .btn-primary:hover {
  background: var(--primary-200);
  border-color: var(--primary-300);
  box-shadow: 0 0 0 3px var(--ring);
}

.btn-secondary {
  background: var(--bg-muted);
  color: var(--fg-secondary);
  border-color: var(--border);
}
.btn-secondary:hover {
  background: var(--bg-subtle);
  border-color: var(--border-hover);
  color: var(--fg);
}

.btn-success {
  background: var(--success-50);
  color: var(--success-700);
  border-color: var(--success-100);
}
.btn-success:hover {
  background: var(--success-100);
  border-color: var(--success-400);
  box-shadow: 0 0 0 3px hsl(90 70% 37% / 0.15);
}
.dark .btn-success {
  background: var(--success-100);
  color: var(--success-500);
  border-color: var(--success-400);
}

.btn-lg { font-size: 17px; padding: 14px 36px; }
.btn-sm { font-size: 13px; padding: 8px 18px; }

.btn:disabled, .btn[disabled] {
  opacity: 0.5;
  cursor: not-allowed;
  pointer-events: none;
}

/* Cards */
.card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-xl);
  padding: 20px;
  transition: box-shadow 0.25s var(--ease), transform 0.25s var(--ease), border-color 0.2s;
}
.card:hover {
  box-shadow: var(--shadow-lg);
  transform: scale(1.01);
}
.card.clickable { cursor: pointer; }
.card.clickable:hover { border-color: var(--primary-300); }
.card.selected {
  border-color: var(--primary-500);
  box-shadow: 0 0 0 3px var(--ring);
}

/* Chips */
.chip {
  font-size: 13px;
  font-weight: 600;
  padding: 5px 12px;
  border-radius: var(--radius-pill);
  display: inline-flex;
  align-items: center;
  gap: 5px;
}
.chip-primary { background: var(--primary-50); color: var(--primary-700); }
.dark .chip-primary { color: var(--primary-400); }
.chip-amber { background: var(--amber-50); color: var(--amber-700); }
.dark .chip-amber { color: var(--amber-400); }
.chip-success { background: var(--success-50); color: var(--success-700); }
.dark .chip-success { color: var(--success-400); }
.chip-neutral { background: var(--bg-muted); color: var(--fg-muted); }

/* Badge */
.badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-family: var(--font-body);
  font-size: 12px;
  font-weight: 600;
  padding: 4px 12px;
  border-radius: var(--radius-pill);
}
.badge-coming-soon {
  background: var(--amber-50);
  color: var(--amber-700);
  border: 1px solid var(--amber-200);
}
.dark .badge-coming-soon { color: var(--amber-400); }

/* Toast */
.toast {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 12px 16px;
  border-radius: var(--radius-xl);
  font-size: 14px;
  font-weight: 500;
  position: fixed;
  bottom: 32px;
  left: 50%;
  transform: translateX(-50%) scale(0.92);
  opacity: 0;
  filter: blur(4px);
  transition: all 0.3s var(--ease);
  z-index: 200;
  white-space: nowrap;
}
.toast.show { opacity: 1; transform: translateX(-50%) scale(1); filter: blur(0); }
.toast-success { background: var(--success-50); color: var(--success-600); border: 1px solid var(--success-200); }
.dark .toast-success { color: var(--success-500); border-color: var(--success-300); }
.toast-error { background: var(--coral-50); color: var(--coral-600); border: 1px solid var(--coral-200); }
.dark .toast-error { color: var(--coral-500); border-color: var(--coral-300); }

/* Answer tiles */
.answer-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
}
.answer-tile {
  padding: 14px;
  border-radius: var(--radius-xl);
  border: 1.5px solid var(--border);
  background: var(--bg-card);
  font-family: var(--font-body);
  font-size: 15px;
  font-weight: 500;
  color: var(--fg-secondary);
  text-align: center;
  cursor: pointer;
  transition: all 0.2s var(--ease);
}
.answer-tile:hover {
  border-color: var(--primary-400);
  background: var(--primary-50);
  color: var(--primary-700);
}
.dark .answer-tile:hover { color: var(--primary-400); }
.answer-tile:active { transform: scale(0.97); }
.answer-tile.correct {
  border-color: var(--success-200);
  background: var(--success-50);
  color: var(--success-600);
  pointer-events: none;
}
.dark .answer-tile.correct { border-color: var(--success-300); color: var(--success-500); }
.answer-tile.wrong {
  border-color: var(--coral-200);
  background: var(--coral-50);
  color: var(--coral-600);
  pointer-events: none;
}
.dark .answer-tile.wrong { border-color: var(--coral-300); color: var(--coral-500); }
.answer-tile.disabled { pointer-events: none; opacity: 0.6; }

/* Progress bar */
.progress-track {
  height: 6px;
  background: var(--bg-muted);
  border-radius: var(--radius-pill);
  overflow: hidden;
}
.progress-fill {
  height: 100%;
  border-radius: var(--radius-pill);
  background: linear-gradient(90deg, var(--primary-400), var(--primary-500));
  transition: width 0.6s var(--ease);
}

/* Section labels */
.section-label {
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 1.2px;
  color: var(--primary-500);
  margin-bottom: 6px;
}

/* Divider with text */
.divider-text {
  display: flex;
  align-items: center;
  gap: 16px;
  margin: 24px 0;
  color: var(--fg-hint);
  font-size: 13px;
  font-weight: 500;
}
.divider-text::before,
.divider-text::after {
  content: "";
  flex: 1;
  height: 1px;
  background: var(--border);
}

/* Avatar */
.avatar {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-heading);
  font-size: 16px;
  font-weight: 700;
  color: #fff;
  flex-shrink: 0;
}
.dark .avatar {
  filter: brightness(0.8) saturate(1.3);
}

/* ══════════════════════════════════════
   ANIMATIONS
   ══════════════════════════════════════ */
@keyframes fadeScale {
  from { opacity: 0; transform: scale(0.95); filter: blur(3px); }
  to { opacity: 1; transform: scale(1); filter: blur(0); }
}
@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}
@keyframes softPop {
  0% { opacity: 0; transform: scale(0.9); }
  70% { opacity: 1; transform: scale(1.02); }
  100% { opacity: 1; transform: scale(1); }
}
@keyframes breathe {
  0%, 100% { transform: scale(1); opacity: 0.85; }
  50% { transform: scale(1.03); opacity: 1; }
}
@keyframes float {
  0%, 100% { transform: translate(var(--tx, 0), var(--ty, 0)) scale(1); }
  50% { transform: translate(calc(var(--tx, 0) + 8px), calc(var(--ty, 0) - 6px)) scale(1.05); }
}
@keyframes absorb {
  0% { opacity: 1; transform: translate(var(--tx, 0), var(--ty, 0)) scale(1); }
  100% { opacity: 0; transform: translate(0, 0) scale(0.3); }
}
@keyframes popIn {
  0% { opacity: 0; transform: scale(0.8); filter: blur(2px); }
  60% { transform: scale(1.03); filter: blur(0); }
  100% { opacity: 1; transform: scale(1); }
}
@keyframes pulse {
  0%, 100% { opacity: 0.4; }
  50% { opacity: 1; }
}
@keyframes shimmer {
  0% { opacity: 0.5; }
  50% { opacity: 0.8; }
  100% { opacity: 0.5; }
}

/* ── Transition utilities (Alpine x-transition) ── */
.ds-fade-enter { transition: opacity 0.25s var(--ease), transform 0.25s var(--ease), filter 0.25s var(--ease); }
.ds-fade-leave { transition: opacity 0.15s var(--ease), transform 0.15s var(--ease), filter 0.15s var(--ease); }
.ds-fade-from { opacity: 0; transform: scale(0.97); filter: blur(2px); }
.ds-fade-to { opacity: 1; transform: scale(1); filter: blur(0); }

.animate-fade-up {
  opacity: 0;
  animation: fadeScale 0.5s var(--ease) forwards;
}
.stagger-1 { animation-delay: 0.05s; }
.stagger-2 { animation-delay: 0.1s; }
.stagger-3 { animation-delay: 0.15s; }
.stagger-4 { animation-delay: 0.2s; }
.stagger-5 { animation-delay: 0.25s; }