/* ===========================================
   Super Maths Hero - Components CSS
   iOS Native Design - Buttons, Cards, Modals, Forms, Badges
   =========================================== */

/* ===== iOS Navigation Bar ===== */
.ios-nav {
  background: rgba(249, 249, 249, 0.94);
  backdrop-filter: saturate(180%) blur(20px);
  -webkit-backdrop-filter: saturate(180%) blur(20px);
  border-bottom: 0.5px solid rgba(0, 0, 0, 0.3);
  padding: 12px 16px;
  position: sticky;
  top: 0;
  z-index: var(--z-sticky);
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 44px;
}

.ios-nav-title {
  font-weight: 600;
  font-size: var(--font-size-body);
  text-align: center;
  color: var(--text-primary);
  flex: 1;
}

/* ===== Buttons - iOS Style ===== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
  padding: 14px 20px;
  font-family: var(--font-system);
  font-size: var(--font-size-body);
  font-weight: 600;
  text-align: center;
  text-decoration: none;
  border: none;
  border-radius: var(--radius-lg);
  cursor: pointer;
  transition: all var(--transition-fast);
  user-select: none;
  -webkit-user-select: none;
  touch-action: manipulation;
  min-height: 50px;
}

.btn:active {
  opacity: 0.8;
  transform: scale(0.96);
}

/* Ripple effect */
.ripple {
  position: relative;
  overflow: hidden;
}

.ripple::after {
  content: "";
  display: block;
  position: absolute;
  width: 100%;
  height: 100%;
  top: 0;
  left: 0;
  pointer-events: none;
  background-image: radial-gradient(circle, #fff 10%, transparent 10.01%);
  background-repeat: no-repeat;
  background-position: 50%;
  transform: scale(10, 10);
  opacity: 0;
  transition: transform .5s, opacity 1s;
}

.ripple:active::after {
  transform: scale(0, 0);
  opacity: .3;
  transition: 0s;
}

.btn:disabled {
  opacity: 0.4;
  cursor: not-allowed;
  transform: none;
}

/* Button Variants - Playful Style */
.btn-primary {
  background: linear-gradient(135deg, var(--accent-blue) 0%, var(--accent-purple) 100%);
  color: var(--text-white);
  box-shadow: 0 4px 12px rgba(100, 181, 246, 0.3);
  border: 2px solid transparent;
}

.btn-primary:active:not(:disabled) {
  background: linear-gradient(135deg, #4DA6F4 0%, #9A78E9 100%);
  transform: scale(0.97);
}

.btn-secondary {
  background-color: var(--ios-fill);
  color: var(--ios-blue);
}

.btn-secondary:active:not(:disabled) {
  background-color: var(--ios-fill-secondary);
}

.btn-hero {
  background: linear-gradient(135deg, var(--accent-purple) 0%, var(--accent-pink) 100%);
  color: var(--text-white);
  box-shadow: 0 4px 12px rgba(176, 136, 249, 0.3);
}

.btn-hero:active:not(:disabled) {
  background: linear-gradient(135deg, #9A78E9 0%, #F57FA1 100%);
}

.btn-success {
  background: linear-gradient(135deg, var(--accent-green) 0%, #7EEEB4 100%);
  color: var(--text-primary);
  box-shadow: 0 4px 12px rgba(102, 222, 147, 0.3);
}

.btn-error {
  background: linear-gradient(135deg, var(--accent-red) 0%, #FFA5A5 100%);
  color: var(--text-white);
  box-shadow: 0 4px 12px rgba(255, 133, 133, 0.3);
}

.btn-outline {
  background: linear-gradient(135deg, #FFFFFF 0%, var(--pastel-lavender) 100%);
  border: 2px solid rgba(176, 136, 249, 0.2);
  color: var(--text-primary);
  box-shadow: var(--shadow-sm);
  border-radius: var(--radius-lg);
}

.btn-outline:hover:not(:disabled) {
  border-color: var(--accent-purple);
  box-shadow: var(--shadow-md);
}

.btn-outline:active:not(:disabled) {
  background: linear-gradient(135deg, var(--pastel-lavender) 0%, #FFFFFF 100%);
  transform: scale(0.97);
}

.btn-outline.active {
  background: linear-gradient(135deg, var(--accent-purple) 0%, var(--accent-blue) 100%);
  border-color: var(--accent-purple);
  color: var(--text-white);
  box-shadow: 0 4px 12px rgba(176, 136, 249, 0.3);
}

/* iOS Text Button */
.btn-text {
  background: transparent;
  color: var(--ios-blue);
  padding: 8px 12px;
  min-height: auto;
}

.btn-text:active {
  opacity: 0.6;
}

/* Button Sizes */
.btn-sm {
  padding: 10px 16px;
  font-size: var(--font-size-subhead);
  min-height: 44px;
}

.btn-lg {
  padding: 16px 24px;
  font-size: var(--font-size-title3);
  min-height: 56px;
}

.btn-xl {
  padding: 18px 32px;
  font-size: var(--font-size-title2);
  border-radius: var(--radius-xl);
  min-height: 60px;
}

/* Icon Button */
.btn-icon {
  padding: var(--space-md);
  border-radius: var(--radius-round);
  width: 50px;
  height: 50px;
  min-height: 50px;
}

.btn-icon.btn-sm {
  width: 44px;
  height: 44px;
  min-height: 44px;
  padding: var(--space-sm);
}

/* Full Width Button */
.btn-block {
  width: 100%;
}

/* ===== Cards - Playful Style ===== */
.card {
  background-color: var(--bg-primary);
  border-radius: var(--radius-xl);
  padding: var(--space-lg);
  transition: all var(--transition-normal);
  box-shadow: var(--shadow-card);
  border: 1px solid rgba(255, 255, 255, 0.4);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}

.card:hover {
  box-shadow: var(--shadow-md);
}

.card-header {
  margin-bottom: var(--space-sm);
  padding-bottom: var(--space-sm);
  border-bottom: var(--border-separator);
}

.card-title {
  font-size: var(--font-size-footnote);
  font-weight: 400;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: -0.08px;
  margin-bottom: var(--space-sm);
}

.card-body {
  flex: 1;
}

.card-footer {
  margin-top: var(--space-md);
  padding-top: var(--space-md);
  border-top: var(--border-separator);
}

/* Card Variants - iOS Style */
.card-primary {
  background: var(--bg-primary);
}

.card-hero {
  background: var(--bg-primary);
}

.card-success {
  background: var(--bg-primary);
}

/* iOS Card Group */
.ios-card-group {
  background: var(--bg-primary);
  border-radius: var(--radius-lg);
  overflow: hidden;
}

.ios-card-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 12px 16px;
  min-height: 44px;
  background: var(--bg-primary);
}

.ios-card-row:not(:last-child) {
  border-bottom: var(--border-separator);
  margin-left: 16px;
}

/* ===== Mode Selection Cards - Playful ===== */
.mode-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  padding: var(--space-xl);
  cursor: pointer;
  min-height: 160px;
  transition: all var(--transition-fast);
  background: var(--bg-primary);
  border-radius: var(--radius-xxl);
  box-shadow: var(--shadow-card);
  border: 3px solid transparent;
  position: relative;
  overflow: hidden;
}

.mode-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--pastel-yellow), var(--pastel-pink), var(--pastel-blue));
  opacity: 0;
  transition: opacity var(--transition-fast);
}

.mode-card:hover::before {
  opacity: 1;
}

.mode-card:active {
  transform: scale(0.97);
}

.mode-card .mode-icon {
  font-size: 3rem;
  margin-bottom: var(--space-md);
  animation: float 3s ease-in-out infinite;
}

.mode-card .mode-title {
  font-size: var(--font-size-title3);
  font-weight: 700;
  margin-bottom: var(--space-xs);
  color: var(--text-primary);
}

.mode-card .mode-desc {
  font-size: var(--font-size-subhead);
  color: var(--text-secondary);
}

/* Mode card color accents - More playful */
.mode-card.card-success {
  border-color: var(--pastel-green);
  background: linear-gradient(135deg, #FFFFFF 0%, var(--pastel-green) 100%);
}

.mode-card.card-success:hover {
  box-shadow: 0 6px 20px rgba(102, 222, 147, 0.3);
}

.mode-card.card-hero {
  border-color: var(--pastel-blue);
  background: linear-gradient(135deg, #FFFFFF 0%, var(--pastel-blue) 100%);
}

.mode-card.card-hero:hover {
  box-shadow: 0 6px 20px rgba(100, 181, 246, 0.3);
}

.mode-card.card-primary {
  border-color: var(--pastel-orange);
  background: linear-gradient(135deg, #FFFFFF 0%, var(--pastel-orange) 100%);
}

.mode-card.card-primary:hover {
  box-shadow: 0 6px 20px rgba(255, 179, 71, 0.3);
}

/* ===== Modals / Bottom Sheet - iOS Style ===== */
.modal-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-color: rgba(0, 0, 0, 0.4);
  display: flex;
  align-items: flex-end;
  justify-content: center;
  z-index: var(--z-modal);
  opacity: 0;
  visibility: hidden;
  transition: opacity var(--transition-normal), visibility var(--transition-normal);
  padding: 0;
}

.modal-overlay.active {
  opacity: 1;
  visibility: visible;
}

.modal {
  background-color: var(--bg-secondary);
  border-radius: var(--radius-xl) var(--radius-xl) 0 0;
  width: 100%;
  max-width: 100%;
  max-height: 90vh;
  overflow-y: auto;
  transform: translateY(100%);
  transition: transform 0.3s cubic-bezier(0.32, 0.72, 0, 1);
  padding-bottom: env(safe-area-inset-bottom, 16px);
}

.modal-overlay.active .modal {
  transform: translateY(0);
}

/* iOS Sheet Handle */
.modal::before {
  content: '';
  display: block;
  width: 36px;
  height: 5px;
  background: rgba(60, 60, 67, 0.3);
  border-radius: 3px;
  margin: 8px auto 16px;
}

.modal-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 var(--space-md) var(--space-md);
  border-bottom: none;
  background-color: transparent;
}

.modal-title {
  font-size: var(--font-size-title3);
  font-weight: 600;
  margin: 0;
  color: var(--text-primary);
}

.modal-close {
  font-size: var(--font-size-title2);
  width: 30px;
  height: 30px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-round);
  background-color: var(--ios-fill);
  color: var(--ios-gray);
  transition: background-color var(--transition-fast);
}

.modal-close:active {
  background-color: var(--ios-fill-secondary);
}

.modal-body {
  padding: var(--space-md);
}

.modal-footer {
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
  padding: var(--space-md);
  border-top: none;
}

/* ===== Forms - iOS Style ===== */
.form-group {
  margin-bottom: var(--space-md);
}

.form-label {
  display: block;
  font-size: var(--font-size-footnote);
  font-weight: 400;
  margin-bottom: var(--space-xs);
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: -0.08px;
  padding-left: var(--space-md);
}

.form-input {
  width: 100%;
  padding: 12px 16px;
  font-size: var(--font-size-body);
  border: none;
  border-radius: var(--radius-md);
  background-color: var(--bg-primary);
  color: var(--text-primary);
  transition: box-shadow var(--transition-fast);
}

.form-input:focus {
  outline: none;
  box-shadow: 0 0 0 4px rgba(0, 122, 255, 0.3);
}

/* Playful Range Slider */
.form-range {
  width: 100%;
  height: 28px;
  -webkit-appearance: none;
  appearance: none;
  background: transparent;
  cursor: pointer;
}

.form-range::-webkit-slider-runnable-track {
  width: 100%;
  height: 8px;
  background: linear-gradient(90deg, var(--pastel-lavender) 0%, var(--pastel-pink) 50%, var(--pastel-blue) 100%);
  border-radius: var(--radius-pill);
  border: 2px solid rgba(176, 136, 249, 0.15);
}

.form-range::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 32px;
  height: 32px;
  background: linear-gradient(135deg, #FFFFFF 0%, var(--pastel-lavender) 100%);
  border: 3px solid var(--accent-purple);
  border-radius: var(--radius-round);
  margin-top: -14px;
  box-shadow: 0 4px 12px rgba(176, 136, 249, 0.3), 0 2px 4px rgba(0, 0, 0, 0.1);
  transition: all var(--transition-fast);
}

.form-range::-webkit-slider-thumb:active {
  transform: scale(1.15);
  box-shadow: 0 6px 16px rgba(176, 136, 249, 0.4);
}

.form-range::-moz-range-track {
  width: 100%;
  height: 8px;
  background: linear-gradient(90deg, var(--pastel-lavender) 0%, var(--pastel-pink) 50%, var(--pastel-blue) 100%);
  border-radius: var(--radius-pill);
  border: 2px solid rgba(176, 136, 249, 0.15);
}

.form-range::-moz-range-thumb {
  width: 32px;
  height: 32px;
  background: linear-gradient(135deg, #FFFFFF 0%, var(--pastel-lavender) 100%);
  border: 3px solid var(--accent-purple);
  border-radius: var(--radius-round);
  box-shadow: 0 4px 12px rgba(176, 136, 249, 0.3), 0 2px 4px rgba(0, 0, 0, 0.1);
}

.range-value {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: var(--font-size-title1);
  font-weight: 700;
  color: var(--accent-purple);
  min-width: 70px;
  padding: var(--space-xs) var(--space-sm);
  background: linear-gradient(135deg, var(--pastel-lavender) 0%, var(--pastel-pink) 100%);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
}

/* Playful Toggle Switch */
.toggle {
  position: relative;
  display: inline-flex;
  align-items: center;
  cursor: pointer;
}

.toggle-input {
  position: absolute;
  opacity: 0;
  width: 0;
  height: 0;
}

.toggle-slider {
  width: 56px;
  height: 32px;
  background: linear-gradient(135deg, #E8E8F0 0%, #D8D8E0 100%);
  border: 2px solid rgba(176, 136, 249, 0.1);
  border-radius: 32px;
  transition: all 0.3s ease;
  position: relative;
  flex-shrink: 0;
}

.toggle-slider::before {
  content: '';
  position: absolute;
  width: 26px;
  height: 26px;
  background: linear-gradient(135deg, #FFFFFF 0%, #F8F8FF 100%);
  border-radius: var(--radius-round);
  top: 1px;
  left: 1px;
  box-shadow: 0 2px 8px rgba(176, 136, 249, 0.2), 0 1px 2px rgba(0, 0, 0, 0.1);
  transition: transform 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
}

.toggle-input:checked+.toggle-slider {
  background: linear-gradient(135deg, var(--accent-green) 0%, #7EEEB4 100%);
  border-color: rgba(102, 222, 147, 0.3);
  box-shadow: 0 2px 8px rgba(102, 222, 147, 0.3);
}

.toggle-input:checked+.toggle-slider::before {
  transform: translateX(24px);
}

.toggle-label {
  margin-left: var(--space-md);
  font-weight: 500;
  font-size: var(--font-size-body);
  color: var(--text-primary);
}

/* iOS Segmented Control */
.ios-segmented {
  display: flex;
  background: rgba(118, 118, 128, 0.12);
  border-radius: 9px;
  padding: 2px;
}

.ios-segment {
  flex: 1;
  padding: 7px 12px;
  border-radius: 7px;
  font-size: var(--font-size-footnote);
  font-weight: 500;
  text-align: center;
  background: transparent;
  border: none;
  color: var(--text-primary);
  transition: all 0.2s ease;
  cursor: pointer;
}

.ios-segment.active {
  background: var(--bg-primary);
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.08), 0 1px 2px rgba(0, 0, 0, 0.12);
}

/* ===== Badges - Playful Style with Sparkle ===== */
.badge {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 72px;
  height: 72px;
  font-size: 2rem;
  background: linear-gradient(135deg, var(--accent-yellow) 0%, var(--accent-orange) 100%);
  border: 3px solid rgba(255, 255, 255, 0.5);
  border-radius: var(--radius-xl);
  box-shadow: 0 4px 12px rgba(255, 217, 61, 0.4), inset 0 2px 4px rgba(255, 255, 255, 0.3);
  transition: all var(--transition-fast);
  position: relative;
  overflow: hidden;
}

/* Sparkle effect on badges */
.badge::before {
  content: '';
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: linear-gradient(45deg,
      transparent 30%,
      rgba(255, 255, 255, 0.5) 50%,
      transparent 70%);
  animation: badgeSparkle 3s ease-in-out infinite;
  pointer-events: none;
}

@keyframes badgeSparkle {

  0%,
  100% {
    transform: translateX(-100%) rotate(45deg);
  }

  50% {
    transform: translateX(100%) rotate(45deg);
  }
}

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

.badge.locked {
  background: var(--ios-fill);
  filter: grayscale(1);
  opacity: 0.5;
  box-shadow: none;
  border-color: transparent;
}

.badge.locked::before {
  display: none;
}

.badge.locked::after {
  content: '🔒';
  position: absolute;
  font-size: 0.75rem;
  bottom: -2px;
  right: -2px;
}

.badge-sm {
  width: 48px;
  height: 48px;
  font-size: 1.25rem;
  border-radius: var(--radius-md);
}

.badge-lg {
  width: 88px;
  height: 88px;
  font-size: 2.5rem;
  border-radius: var(--radius-xxl);
}

/* Badge Card */
.badge-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  padding: var(--space-sm);
  position: relative;
}

.badge-card .badge-name {
  font-size: var(--font-size-caption1);
  font-weight: 500;
  margin-top: var(--space-xs);
  color: var(--text-primary);
}

.badge-card .badge-desc {
  font-size: var(--font-size-caption2);
  color: var(--text-secondary);
}

/* ===== Progress Bar - Playful Rainbow Style ===== */
.progress {
  width: 100%;
  height: 10px;
  background-color: var(--ios-fill);
  border: none;
  border-radius: var(--radius-pill);
  overflow: hidden;
  box-shadow: inset 0 2px 4px rgba(0, 0, 0, 0.05);
}

.progress-bar {
  height: 100%;
  background: linear-gradient(90deg,
      var(--accent-green) 0%,
      var(--accent-blue) 25%,
      var(--accent-purple) 50%,
      var(--accent-pink) 75%,
      var(--accent-yellow) 100%);
  background-size: 200% 100%;
  border-radius: var(--radius-pill);
  transition: width var(--transition-normal);
  animation: rainbowProgress 3s linear infinite;
}

@keyframes rainbowProgress {
  0% {
    background-position: 0% 0%;
  }

  100% {
    background-position: 200% 0%;
  }
}

.daily-challenge-progress {
  height: 12px;
  background: rgba(0, 0, 0, 0.1);
  border-radius: 6px;
  overflow: hidden;
  margin: 10px 0;
  border: 1px solid rgba(255, 255, 255, 0.1);
}

html.dark-mode .daily-challenge-progress {
  background: rgba(255, 255, 255, 0.05);
  border-color: rgba(255, 255, 255, 0.05);
}

.daily-challenge-progress-bar {
  height: 100%;
  background: linear-gradient(90deg, var(--accent-blue), var(--accent-purple));
  transition: width 0.5s cubic-bezier(0.4, 0, 0.2, 1);
  box-shadow: 0 0 10px rgba(176, 136, 249, 0.3);
}

/* XP Progress */
.xp-bar {
  position: relative;
  height: 12px;
}

.xp-bar .progress-bar {
  background: linear-gradient(90deg,
      var(--accent-purple) 0%,
      var(--accent-pink) 50%,
      var(--accent-yellow) 100%);
  background-size: 200% 100%;
}

.xp-label {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  font-weight: 600;
  font-size: var(--font-size-caption2);
  color: var(--text-primary);
}

/* ===== Stats Display - iOS Style ===== */
.stat-box {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: var(--space-md);
  background-color: var(--bg-primary);
  border: none;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-card);
  min-width: 80px;
}

.stat-value {
  font-size: var(--font-size-title2);
  font-weight: 700;
  line-height: 1;
  color: var(--text-primary);
}

.stat-label {
  font-size: var(--font-size-caption2);
  font-weight: 500;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.5px;
  margin-top: 2px;
}

/* Points Earned - Special styling */
.stat-points {
  background: linear-gradient(135deg, #FFD700 0%, #FFA500 100%);
  box-shadow: 0 2px 8px rgba(255, 193, 7, 0.4);
}

.stat-points .stat-value {
  color: #5D4037;
  font-weight: 800;
}

.stat-points .stat-label {
  color: rgba(93, 64, 55, 0.8);
}

/* iOS Stats Bar */
.ios-stats-bar {
  display: flex;
  justify-content: space-around;
  padding: 12px 16px;
  background: var(--bg-primary);
  border-radius: var(--radius-lg);
}

.ios-stat {
  text-align: center;
}

.ios-stat-value {
  font-size: var(--font-size-title2);
  font-weight: 600;
  color: var(--text-primary);
}

.ios-stat-label {
  font-size: var(--font-size-caption2);
  font-weight: 500;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.5px;
  margin-top: 2px;
}

/* ===== Game UI Elements - Playful Style ===== */
.problem-display {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-md);
  font-size: 48px;
  font-weight: 700;
  font-family: var(--font-display);
  padding: var(--space-xl) var(--space-lg);
  background: linear-gradient(135deg, #FFFFFF 0%, var(--pastel-lavender) 50%, var(--pastel-mint) 100%);
  border: 3px solid rgba(176, 136, 249, 0.2);
  border-radius: var(--radius-xxl);
  box-shadow: var(--shadow-md);
}

.problem-number {
  color: var(--text-primary);
}

/* Colored operators based on type */
.problem-operator {
  color: var(--accent-purple);
  font-weight: 800;
}

.problem-operator[data-op="+"] {
  color: var(--accent-green);
}

.problem-operator[data-op="-"] {
  color: var(--accent-red);
}

.problem-operator[data-op="×"] {
  color: var(--accent-blue);
}

.problem-operator[data-op="÷"] {
  color: var(--accent-orange);
}

.problem-equals {
  color: var(--text-secondary);
}

.problem-answer {
  min-width: 90px;
  color: var(--accent-purple);
  text-align: center;
  padding: var(--space-xs) var(--space-md);
  background: rgba(176, 136, 249, 0.1);
  border-radius: var(--radius-md);
  font-variant-numeric: tabular-nums;
}

/* Lives Display */
.lives-display {
  display: flex;
  gap: 4px;
}

.life {
  font-size: var(--font-size-title3);
  transition: transform var(--transition-fast), opacity var(--transition-fast);
}

.life.lost {
  opacity: 0.3;
  transform: scale(0.8);
  filter: grayscale(1);
}

/* Streak Display */
.streak-display {
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
  padding: var(--space-sm) var(--space-md);
  background: linear-gradient(135deg, var(--accent-orange) 0%, var(--accent-yellow) 100%);
  border: none;
  border-radius: var(--radius-pill);
  font-weight: 600;
  color: var(--text-white);
  box-shadow: 0 4px 12px rgba(255, 179, 71, 0.4);
}

.streak-icon {
  font-size: var(--font-size-body);
}

.streak-count {
  font-size: var(--font-size-body);
}

/* ===== Combo Message System ===== */
.combo-container {
  position: fixed;
  top: 25%;
  /* Moved up from 50% to avoid covering input buttons */
  left: 50%;
  transform: translate(-50%, -50%);
  z-index: 1000;
  pointer-events: none;
}

.combo-message {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-sm);
  padding: var(--space-lg) var(--space-xl);
  border-radius: var(--radius-xxl);
  font-family: var(--font-display);
  font-weight: 700;
  text-align: center;
  animation: comboAppear 0.5s ease-out forwards, comboDisappear 0.3s ease-in 1.5s forwards;
  text-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
}

@keyframes comboAppear {
  0% {
    opacity: 0;
    transform: scale(0.5) translateY(20px);
  }

  50% {
    transform: scale(1.1) translateY(-10px);
  }

  100% {
    opacity: 1;
    transform: scale(1) translateY(0);
  }
}

@keyframes comboDisappear {
  to {
    opacity: 0;
    transform: scale(0.8) translateY(-30px);
  }
}

.combo-text {
  font-size: var(--font-size-title1);
}

.combo-streak {
  font-size: var(--font-size-footnote);
  opacity: 0.9;
}

/* Combo levels with different styles */
.combo-2 {
  background: linear-gradient(135deg, var(--pastel-green) 0%, var(--accent-green) 100%);
  color: #2E8B57;
  box-shadow: 0 6px 20px rgba(102, 222, 147, 0.5);
}

.combo-5 {
  background: linear-gradient(135deg, var(--pastel-yellow) 0%, var(--accent-yellow) 100%);
  color: #B8860B;
  box-shadow: 0 6px 20px rgba(255, 217, 61, 0.5);
  font-size: 1.1em;
}

.combo-10 {
  background: linear-gradient(135deg, var(--pastel-orange) 0%, var(--accent-orange) 100%);
  color: #CD5500;
  box-shadow: 0 8px 24px rgba(255, 179, 71, 0.6);
  font-size: 1.2em;
  animation: comboAppear 0.5s ease-out forwards, comboFire 0.2s ease-in-out infinite, comboDisappear 0.3s ease-in 2s forwards;
}

@keyframes comboFire {

  0%,
  100% {
    transform: scale(1) rotate(-1deg);
  }

  50% {
    transform: scale(1.02) rotate(1deg);
  }
}

.combo-15 {
  background: linear-gradient(135deg, var(--pastel-pink) 0%, var(--accent-pink) 100%);
  color: #C71585;
  box-shadow: 0 8px 28px rgba(255, 143, 177, 0.6);
  font-size: 1.3em;
}

.combo-20 {
  background: linear-gradient(135deg,
      var(--accent-yellow) 0%,
      var(--accent-orange) 20%,
      var(--accent-pink) 40%,
      var(--accent-purple) 60%,
      var(--accent-blue) 80%,
      var(--accent-green) 100%);
  background-size: 200% 200%;
  color: white;
  box-shadow: 0 10px 32px rgba(176, 136, 249, 0.6);
  font-size: 1.5em;
  animation: comboAppear 0.5s ease-out forwards, rainbowShift 1s ease-in-out infinite, comboDisappear 0.3s ease-in 2.5s forwards;
}

@keyframes rainbowShift {

  0%,
  100% {
    background-position: 0% 50%;
  }

  50% {
    background-position: 100% 50%;
  }
}

/* Combo star particles */
.combo-stars {
  position: absolute;
  width: 100%;
  height: 100%;
  top: 0;
  left: 0;
  overflow: visible;
  pointer-events: none;
}

.combo-star {
  position: absolute;
  font-size: 1.5rem;
  animation: comboStarFloat 1s ease-out forwards;
}

@keyframes comboStarFloat {
  0% {
    opacity: 1;
    transform: translate(0, 0) scale(0.5);
  }

  100% {
    opacity: 0;
    transform: translate(var(--star-x, 30px), var(--star-y, -50px)) scale(1.2) rotate(180deg);
  }
}

/* ===== Numpad - iOS Style ===== */
.numpad {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
  max-width: 280px;
  margin: 0 auto;
  padding: var(--space-md);
}

.numpad-btn {
  aspect-ratio: 1;
  font-size: 28px;
  font-weight: 400;
  font-family: var(--font-system);
  background: var(--bg-primary);
  border: none;
  border-radius: var(--radius-round);
  box-shadow: var(--shadow-card);
  transition: all 0.1s ease;
  color: var(--text-primary);
}

.numpad-btn:active {
  background: #D1D1D6;
  transform: scale(0.95);
}

.numpad-btn.btn-fraction {
  font-size: var(--font-size-title2);
  font-weight: 500;
}

.numpad-btn.btn-backspace {
  font-size: var(--font-size-title3);
  color: var(--text-secondary);
}

.numpad-btn.btn-clear {
  font-size: var(--font-size-title3);
  color: var(--color-error, #FF3B30);
}

.numpad-btn.btn-submit {
  grid-column: span 2;
  aspect-ratio: auto;
  height: 56px;
  border-radius: var(--radius-xl);
  background: linear-gradient(135deg, var(--accent-green) 0%, #7EEEB4 100%);
  color: var(--text-white);
  font-size: var(--font-size-title2);
  box-shadow: 0 4px 12px rgba(102, 222, 147, 0.3);
}

.numpad-btn.btn-submit:active {
  background: linear-gradient(135deg, #2DA94F 0%, var(--accent-green) 100%);
}

/* ===== Multiple Choice - Playful Style ===== */
.choices-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
  max-width: 360px;
  margin: 0 auto;
  padding: var(--space-md);
}

.choice-btn {
  padding: var(--space-lg);
  font-size: var(--font-size-title1);
  font-weight: 600;
  font-family: var(--font-display);
  background: linear-gradient(135deg, #FFFFFF 0%, var(--pastel-lavender) 100%);
  border: 3px solid rgba(176, 136, 249, 0.2);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-card);
  transition: all 0.15s ease;
  color: var(--text-primary);
}

.choice-btn:hover:not(:disabled) {
  border-color: var(--accent-purple);
  box-shadow: 0 6px 16px rgba(176, 136, 249, 0.25);
}

.choice-btn:active:not(:disabled) {
  transform: scale(0.96);
}

.choice-btn.selected {
  border-color: var(--accent-blue);
  background: linear-gradient(135deg, #FFFFFF 0%, var(--pastel-blue) 100%);
  box-shadow: 0 4px 12px rgba(100, 181, 246, 0.3);
}

.choice-btn.correct {
  border-color: var(--accent-green);
  background: linear-gradient(135deg, #FFFFFF 0%, var(--pastel-green) 100%);
  color: #2E8B57;
  box-shadow: 0 4px 12px rgba(102, 222, 147, 0.4);
}

.choice-btn.wrong {
  border-color: var(--accent-red);
  background: linear-gradient(135deg, #FFFFFF 0%, var(--pastel-coral) 100%);
  color: #CD5C5C;
  box-shadow: 0 4px 12px rgba(255, 133, 133, 0.3);
}

.choice-btn.reveal-correct {
  border-color: var(--ios-green);
  background: rgba(52, 199, 89, 0.15);
}

.choice-btn.hint-eliminated {
  opacity: 0.3;
  text-decoration: line-through;
  pointer-events: none;
  transition: opacity 0.3s ease;
}

/* Pulsing animation to highlight the correct answer */
.choice-btn.correct-reveal {
  border-color: var(--ios-green);
  background: rgba(52, 199, 89, 0.2);
  animation: correctRevealPulse 0.6s ease-in-out 3;
  box-shadow: 0 0 0 0 rgba(52, 199, 89, 0.4);
}

@keyframes correctRevealPulse {
  0% {
    box-shadow: 0 0 0 0 rgba(52, 199, 89, 0.5);
    transform: scale(1);
  }

  50% {
    box-shadow: 0 0 0 8px rgba(52, 199, 89, 0);
    transform: scale(1.02);
  }

  100% {
    box-shadow: 0 0 0 0 rgba(52, 199, 89, 0);
  }
}

/* Correct answer highlight for numpad mode */
.problem-answer.correct-highlight {
  color: var(--ios-green);
  animation: correctRevealPulse 0.6s ease-in-out 2;
}

/* ===== Timer - iOS Style ===== */
.timer-display {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
  padding: var(--space-sm) var(--space-md);
  background-color: var(--bg-primary);
  border: none;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-card);
}

.timer-icon {
  font-size: var(--font-size-body);
}

.timer-value {
  font-size: var(--font-size-title3);
  font-weight: 600;
  font-variant-numeric: tabular-nums;
  color: var(--text-primary);
}

.timer-display.warning {
  background-color: var(--ios-orange);
  color: var(--text-white);
}

.timer-display.warning .timer-value {
  color: var(--text-white);
}

.timer-display.danger {
  background-color: var(--ios-red);
  color: var(--text-white);
}

.timer-display.danger .timer-value {
  color: var(--text-white);
}

/* ===== Toast Notifications - iOS Style ===== */
.toast-container {
  position: fixed;
  top: calc(var(--space-lg) + env(safe-area-inset-top, 0px));
  left: 50%;
  transform: translateX(-50%);
  z-index: var(--z-toast);
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
  pointer-events: none;
  width: calc(100% - 32px);
  max-width: 360px;
}

.toast {
  padding: 14px 20px;
  background-color: rgba(50, 50, 50, 0.9);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: none;
  border-radius: var(--radius-lg);
  font-weight: 500;
  font-size: var(--font-size-subhead);
  color: var(--text-white);
  animation: slideInDown var(--transition-normal);
  pointer-events: auto;
  text-align: center;
}

.toast-success {
  background-color: rgba(52, 199, 89, 0.95);
}

.toast-error {
  background-color: rgba(255, 59, 48, 0.95);
}

.toast-badge {
  background-color: rgba(88, 86, 214, 0.95);
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-md);
}

/* ===== Header Bar - iOS Style ===== */
.header-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-sm) var(--space-md);
  background: rgba(242, 242, 247, 0.94);
  backdrop-filter: saturate(180%) blur(20px);
  -webkit-backdrop-filter: saturate(180%) blur(20px);
  border-bottom: var(--border-separator);
}

.header-title {
  font-size: var(--font-size-body);
  font-weight: 600;
  margin: 0;
  color: var(--text-primary);
}

.header-actions {
  display: flex;
  gap: var(--space-sm);
}

/* ===== Footer Bar ===== */
.footer-bar {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-md);
  margin-top: auto;
}

/* ===== Empty State ===== */
.empty-state {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: var(--space-xxl);
  text-align: center;
}

.empty-state-icon {
  font-size: 3rem;
  margin-bottom: var(--space-md);
}

.empty-state-title {
  font-size: var(--font-size-title3);
  font-weight: 600;
  margin-bottom: var(--space-sm);
  color: var(--text-primary);
}

.empty-state-text {
  color: var(--text-secondary);
  font-size: var(--font-size-subhead);
}

/* ===== Badge Category ===== */
.badge-category-header {
  font-size: var(--font-size-footnote);
  font-weight: 400;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: -0.08px;
  margin-top: var(--space-lg);
  margin-bottom: var(--space-sm);
  padding: 0 var(--space-md);
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.badge-category-header:first-child {
  margin-top: 0;
}

.badge-category-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(90px, 1fr));
  gap: var(--space-md);
  margin-bottom: var(--space-md);
  background: var(--bg-primary);
  border-radius: var(--radius-lg);
  padding: var(--space-md);
}

/* ===== Active Button States - iOS Style ===== */
.difficulty-btn.active,
.input-method-btn.active,
.timer-btn.active {
  background-color: var(--ios-blue);
  color: var(--text-white);
  border-color: var(--ios-blue);
}

/* ===== Screen Content ===== */
.screen-content {
  width: 100%;
  margin: 0 auto;
  height: 100%;
}

/* All screens inherit overflow-y: auto from .screen base */

/* Home screen scrollable - inherits from .screen base */

/* Scrollable screens - header stays fixed, content scrolls */
#badges-screen {
  overflow: hidden;
  height: 100vh;
  height: 100dvh;
}

#badges-screen > .screen-content {
  flex: 1;
  min-height: 0;
  overflow-y: auto;
  -webkit-overflow-scrolling: touch;
}

/* ===== Text Size Utilities ===== */
.text-sm {
  font-size: var(--font-size-footnote);
}

.text-lg {
  font-size: var(--font-size-title3);
}

.text-xl {
  font-size: var(--font-size-title2);
}

/* ===== HOME SCREEN STYLES - iOS ===== */
.home-container {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-sm);
  width: 100%;
  /* No padding/min-height - parent .screen handles padding and safe areas */
}

/* Title */
.home-header {
  text-align: center;
  flex-shrink: 0;
}

.home-title {
  display: flex;
  flex-direction: column;
  line-height: 1.1;
  margin: 0;
  font-family: var(--font-display);
}

.title-super {
  font-size: clamp(1.25rem, 5vw, 1.75rem);
  font-weight: 600;
  color: var(--accent-orange);
  text-shadow: 0 2px 4px rgba(255, 179, 71, 0.3);
}

.title-maths {
  font-size: clamp(2.5rem, 10vw, 3.5rem);
  font-weight: 700;
  background: linear-gradient(135deg, var(--accent-blue) 0%, var(--accent-purple) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  text-shadow: none;
}

.title-hero {
  font-size: clamp(1.75rem, 8vw, 2.5rem);
  font-weight: 700;
  background: linear-gradient(135deg, var(--accent-purple) 0%, var(--accent-pink) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  text-shadow: none;
}

.home-subtitle {
  font-size: var(--font-size-body);
  color: var(--text-secondary);
  margin-top: var(--space-sm);
  font-weight: 400;
}

/* Mascot */
.home-mascot {
  flex: 0 0 auto;
  display: flex;
  align-items: center;
  justify-content: center;
}

.mascot-img {
  width: clamp(140px, 40vw, 220px);
  height: auto;
  filter: drop-shadow(0 8px 24px rgba(176, 136, 249, 0.3));
  object-fit: contain;
}

/* Subtle bounce animation for mascot */
.mascot-img.animate-float {
  animation: mascotBounce 2s ease-in-out infinite;
}

@keyframes mascotBounce {

  0%,
  100% {
    transform: translateY(0);
  }

  50% {
    transform: translateY(-12px);
  }
}

/* Stats Card - Playful and warm */
.home-stats {
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
  background: linear-gradient(135deg, rgba(255, 255, 255, 0.95) 0%, rgba(255, 240, 179, 0.3) 100%);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: 3px solid rgba(255, 217, 61, 0.3);
  border-radius: var(--radius-xxl);
  box-shadow: 0 6px 24px rgba(255, 217, 61, 0.2);
  padding: var(--space-lg);
  width: 100%;
  max-width: 340px;
}

.stats-card-title {
  font-size: var(--font-size-footnote);
  font-weight: 600;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.5px;
  text-align: center;
  margin-bottom: var(--space-xs);
}

.stats-row {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-lg);
}

.stat-item {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.stat-icon {
  font-size: 1.5rem;
}

.stat-content {
  display: flex;
  flex-direction: column;
}

.stat-number {
  font-size: var(--font-size-title2);
  font-weight: 700;
  color: var(--text-primary);
  line-height: 1.2;
}

.stat-desc {
  font-size: var(--font-size-caption1);
  color: var(--text-secondary);
}

.stat-divider {
  width: 1px;
  height: 40px;
  background: var(--ios-separator);
}

.xp-section {
  width: 100%;
}

.xp-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: var(--space-sm);
}

.xp-label {
  font-size: var(--font-size-footnote);
  color: var(--text-secondary);
  font-weight: 500;
}

.xp-value {
  font-size: var(--font-size-footnote);
  font-weight: 600;
  color: var(--ios-purple);
}

/* Level badge removed - using inline stats now */
.level-badge {
  display: none;
}

/* Play Button - Playful and inviting */
.btn-play {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-md);
  width: 100%;
  max-width: 300px;
  padding: var(--space-lg) var(--space-xl);
  background: linear-gradient(135deg, var(--accent-purple) 0%, var(--accent-pink) 50%, var(--accent-yellow) 100%);
  background-size: 200% 200%;
  border: none;
  border-radius: var(--radius-xxl);
  box-shadow: 0 6px 20px rgba(176, 136, 249, 0.4);
  font-size: var(--font-size-title2);
  font-weight: 700;
  font-family: var(--font-display);
  color: var(--text-white);
  cursor: pointer;
  transition: all 0.2s ease;
  animation: playButtonGlow 3s ease-in-out infinite;
  text-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
}

@keyframes playButtonGlow {

  0%,
  100% {
    background-position: 0% 50%;
  }

  50% {
    background-position: 100% 50%;
  }
}

.btn-play:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(176, 136, 249, 0.5);
}

.btn-play:active {
  transform: scale(0.97) translateY(0);
}

.play-icon {
  font-size: 1.25rem;
}

/* Secondary Actions */
.home-actions {
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
  width: 100%;
  max-width: 300px;
}

.secondary-actions {
  display: flex;
  gap: var(--space-sm);
}

.btn-secondary-action {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
  padding: 14px var(--space-md);
  background: var(--bg-primary);
  border: none;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-card);
  font-size: var(--font-size-subhead);
  font-weight: 500;
  color: var(--text-primary);
  cursor: pointer;
  transition: all 0.15s ease;
}

.btn-secondary-action:active {
  transform: scale(0.98);
  background-color: var(--ios-fill-quaternary);
}

.btn-badges {
  background: var(--bg-primary);
}

.btn-icon-small {
  font-size: 1.1rem;
}

/* ===== BACK BUTTON - iOS Style ===== */
.btn-back {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: var(--space-sm) var(--space-md);
  background: rgba(0, 122, 255, 0.1);
  border: none;
  border-radius: var(--radius-pill);
  font-family: var(--font-system);
  font-size: var(--font-size-subhead);
  font-weight: 500;
  color: var(--ios-blue);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.btn-back:hover {
  background: rgba(0, 122, 255, 0.15);
}

.btn-back:active {
  background: rgba(0, 122, 255, 0.25);
  transform: scale(0.97);
}

.btn-back-icon {
  font-size: 18px;
  font-weight: 600;
  line-height: 1;
}

.btn-back-text {
  font-size: var(--font-size-subhead);
}

/* ===== SCREEN HEADER FIXED - iOS Style ===== */
.screen-header-fixed {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  padding: var(--space-sm) var(--space-md);
  margin-bottom: var(--space-sm);
  flex-shrink: 0;
  background: rgba(253, 248, 243, 0.85);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  z-index: var(--z-sticky);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-card);
  border: 2px solid rgba(176, 136, 249, 0.1);
}

.screen-header-fixed .screen-title {
  flex: 1;
  margin: 0;
  font-size: var(--font-size-body);
  font-weight: 600;
  text-align: center;
}

.screen-header-fixed .badge-counter {
  font-weight: 500;
  font-size: var(--font-size-footnote);
  color: var(--text-secondary);
  padding: var(--space-xs) var(--space-sm);
}

/* ===== SETTINGS SCROLL ===== */
/* Settings screen - header stays fixed, content scrolls */
#settings-screen {
  overflow: hidden;
  height: 100vh;
  height: 100dvh;
}

#settings-screen > .screen-content {
  padding-top: 0;
  flex: 1;
  min-height: 0;
  overflow-y: auto;
  -webkit-overflow-scrolling: touch;
}

.settings-scroll {
  padding-top: 0;
  max-height: none;
}

.settings-content {
  width: 100%;
  max-width: 100%;
  box-sizing: border-box;
}

.settings-content .card {
  width: 100%;
  box-sizing: border-box;
}

/* ===== OPERATIONS GRID - Playful Style ===== */
.operations-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--space-sm);
}

.operation-checkbox {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  padding: 14px;
  background: linear-gradient(135deg, #FFFFFF 0%, var(--pastel-lavender) 100%);
  border: 2px solid rgba(176, 136, 249, 0.15);
  border-radius: var(--radius-lg);
  cursor: pointer;
  transition: all 0.2s ease;
  box-shadow: var(--shadow-sm);
}

.operation-checkbox:hover {
  border-color: rgba(176, 136, 249, 0.3);
  box-shadow: var(--shadow-md);
}

.operation-checkbox:active {
  transform: scale(0.98);
}

.operation-checkbox:has(.operation-input:checked) {
  background: linear-gradient(135deg, var(--pastel-green) 0%, #E8FFF0 100%);
  border-color: var(--accent-green);
  box-shadow: 0 4px 12px rgba(102, 222, 147, 0.25);
}

/* Specific colors for each operation */
.operation-checkbox[data-op="+"]:has(.operation-input:checked) {
  background: linear-gradient(135deg, var(--pastel-green) 0%, #E8FFF0 100%);
  border-color: var(--accent-green);
  box-shadow: 0 4px 12px rgba(102, 222, 147, 0.25);
}

.operation-checkbox[data-op="-"]:has(.operation-input:checked) {
  background: linear-gradient(135deg, var(--pastel-coral) 0%, #FFF0F0 100%);
  border-color: var(--accent-red);
  box-shadow: 0 4px 12px rgba(255, 133, 133, 0.25);
}

.operation-checkbox[data-op="×"]:has(.operation-input:checked) {
  background: linear-gradient(135deg, var(--pastel-blue) 0%, #F0F8FF 100%);
  border-color: var(--accent-blue);
  box-shadow: 0 4px 12px rgba(100, 181, 246, 0.25);
}

.operation-checkbox[data-op="÷"]:has(.operation-input:checked) {
  background: linear-gradient(135deg, var(--pastel-orange) 0%, #FFF8F0 100%);
  border-color: var(--accent-orange);
  box-shadow: 0 4px 12px rgba(255, 179, 71, 0.25);
}

.operation-checkbox[data-op="½"]:has(.operation-input:checked) {
  background: linear-gradient(135deg, var(--pastel-pink) 0%, #FFF0F8 100%);
  border-color: var(--accent-pink);
  box-shadow: 0 4px 12px rgba(255, 143, 177, 0.25);
}

.operation-checkbox[data-op="x"]:has(.operation-input:checked) {
  background: linear-gradient(135deg, var(--pastel-lavender) 0%, #F8F0FF 100%);
  border-color: var(--accent-purple);
  box-shadow: 0 4px 12px rgba(176, 136, 249, 0.25);
}

.operation-checkbox[data-op="%"]:has(.operation-input:checked) {
  background: linear-gradient(135deg, #E8F5E9 0%, #C8E6C9 100%);
  border-color: #4CAF50;
  box-shadow: 0 4px 12px rgba(76, 175, 80, 0.25);
}

.operation-checkbox[data-op="🔄"]:has(.operation-input:checked) {
  background: linear-gradient(135deg, #E3F2FD 0%, #BBDEFB 100%);
  border-color: #2196F3;
  box-shadow: 0 4px 12px rgba(33, 150, 243, 0.25);
}

.operation-input {
  width: 24px;
  height: 24px;
  accent-color: var(--accent-purple);
  cursor: pointer;
  border-radius: var(--radius-sm);
}

.operation-label {
  font-weight: 500;
  font-size: var(--font-size-body);
  white-space: nowrap;
  color: var(--text-primary);
}

/* ===== CARD DANGER ===== */
.card-danger {
  background: var(--bg-primary);
  border-left: 4px solid var(--ios-red);
}

.card-danger .card-title {
  color: var(--ios-red);
}

/* ===== RESULT MESSAGE ===== */
.result-message {
  color: var(--text-secondary);
}

.result-title.success {
  color: var(--ios-green);
}

.result-title.warning {
  color: var(--ios-orange);
}

.result-title.error {
  color: var(--ios-red);
}

/* ===== QUESTION TIMER ===== */
.question-timer-container {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  margin: var(--space-md) auto;
  max-width: 280px;
  width: 100%;
}

.question-timer-bar {
  flex: 1;
  height: 6px;
  background: var(--ios-fill);
  border-radius: var(--radius-pill);
  overflow: hidden;
  border: none;
}

.question-timer-fill {
  height: 100%;
  background: var(--ios-blue);
  border-radius: var(--radius-pill);
  transition: width 0.3s ease;
  width: 100%;
}

.question-timer-fill.warning {
  background: var(--ios-orange);
}

.question-timer-fill.danger {
  background: var(--ios-red);
}

.question-timer-text {
  font-size: var(--font-size-subhead);
  font-weight: 600;
  min-width: 28px;
  text-align: center;
  color: var(--text-primary);
  font-variant-numeric: tabular-nums;
}

.question-timer-text.warning {
  color: var(--ios-orange);
}

.question-timer-text.danger {
  color: var(--ios-red);
}

/* ===== TIMER BUTTONS - Playful Style ===== */
.timer-options {
  display: flex;
  gap: var(--space-sm);
  flex-wrap: wrap;
  justify-content: center;
}

.timer-btn {
  min-width: 75px;
  padding: 12px 16px;
  background: linear-gradient(135deg, #FFFFFF 0%, var(--pastel-blue) 100%);
  border: 2px solid rgba(100, 181, 246, 0.2);
  border-radius: var(--radius-lg);
  font-weight: 600;
  color: var(--text-primary);
  transition: all 0.2s ease;
  box-shadow: var(--shadow-sm);
}

.timer-btn:hover:not(:disabled) {
  border-color: var(--accent-blue);
  box-shadow: var(--shadow-md);
}

.timer-btn:active:not(:disabled) {
  transform: scale(0.97);
}

.timer-btn.active {
  background: linear-gradient(135deg, var(--accent-blue) 0%, var(--accent-purple) 100%);
  border-color: var(--accent-blue);
  color: var(--text-white);
  box-shadow: 0 4px 12px rgba(100, 181, 246, 0.35);
}

/* ===== PAUSE TIME BUTTONS - Playful Style ===== */
.pause-options {
  display: flex;
  gap: var(--space-sm);
  flex-wrap: wrap;
  justify-content: center;
}

.pause-btn {
  min-width: 65px;
  padding: 12px 14px;
  text-align: center;
  background: linear-gradient(135deg, #FFFFFF 0%, var(--pastel-mint) 100%);
  border: 2px solid rgba(102, 222, 147, 0.2);
  border-radius: var(--radius-lg);
  font-weight: 600;
  color: var(--text-primary);
  transition: all 0.2s ease;
  box-shadow: var(--shadow-sm);
}

.pause-btn:hover:not(:disabled) {
  border-color: var(--accent-green);
  box-shadow: var(--shadow-md);
}

.pause-btn:active:not(:disabled) {
  transform: scale(0.97);
}

.pause-btn.active {
  background: linear-gradient(135deg, var(--accent-green) 0%, #7EEEB4 100%);
  border-color: var(--accent-green);
  color: #1B5E20;
  box-shadow: 0 4px 12px rgba(102, 222, 147, 0.35);
}

/* ===== CHOICE BUTTON FEEDBACK ===== */
@keyframes correctPop {
  0% {
    transform: scale(1);
  }

  50% {
    transform: scale(1.02);
  }

  100% {
    transform: scale(1);
  }
}

@keyframes gentleShake {

  0%,
  100% {
    transform: translateX(0);
  }

  25% {
    transform: translateX(-4px);
  }

  75% {
    transform: translateX(4px);
  }
}

.choice-btn.correct {
  animation: correctPop 0.3s ease;
}

.choice-btn.wrong {
  animation: gentleShake 0.3s ease;
}

/* ===== SUBTLE BADGE TOAST ===== */
.toast-badge-mini {
  position: fixed;
  bottom: calc(var(--space-lg) + env(safe-area-inset-bottom, 0px));
  right: var(--space-md);
  background: rgba(88, 86, 214, 0.95);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: none;
  border-radius: var(--radius-lg);
  padding: var(--space-sm) var(--space-md);
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  font-size: var(--font-size-footnote);
  font-weight: 500;
  color: var(--text-white);
  box-shadow: var(--shadow-elevated);
  animation: slideInRight 0.3s ease, fadeOutRight 0.3s ease 2.5s forwards;
  z-index: var(--z-toast);
  max-width: 200px;
}

.toast-badge-mini .badge-emoji {
  font-size: 1.1rem;
}

.toast-badge-mini .badge-text {
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

@keyframes slideInRight {
  from {
    transform: translateX(100%);
    opacity: 0;
  }

  to {
    transform: translateX(0);
    opacity: 1;
  }
}

@keyframes fadeOutRight {
  to {
    opacity: 0;
    transform: translateX(20px);
  }
}

/* ===== Difficulty Grid - Playful Style ===== */
.difficulty-grid {
  display: flex;
  gap: var(--space-sm);
  flex-wrap: wrap;
  justify-content: center;
}

.difficulty-btn {
  flex: 1;
  min-width: 90px;
  text-align: center;
  padding: 14px 16px;
  background: linear-gradient(135deg, #FFFFFF 0%, var(--pastel-lavender) 100%);
  border: 2px solid rgba(176, 136, 249, 0.2);
  border-radius: var(--radius-lg);
  font-weight: 600;
  color: var(--text-primary);
  transition: all 0.2s ease;
  box-shadow: var(--shadow-sm);
}

.difficulty-btn:hover:not(:disabled) {
  border-color: var(--accent-purple);
  box-shadow: var(--shadow-md);
}

.difficulty-btn:active:not(:disabled) {
  transform: scale(0.97);
}

.difficulty-btn.active {
  background: linear-gradient(135deg, var(--accent-purple) 0%, var(--accent-blue) 100%);
  border-color: var(--accent-purple);
  color: var(--text-white);
  box-shadow: 0 4px 12px rgba(176, 136, 249, 0.35);
}

/* Difficulty level specific colors when active */
.difficulty-btn[data-difficulty="easy"].active {
  background: linear-gradient(135deg, var(--accent-green) 0%, #7EEEB4 100%);
  border-color: var(--accent-green);
  box-shadow: 0 4px 12px rgba(102, 222, 147, 0.35);
}

.difficulty-btn[data-difficulty="medium"].active {
  background: linear-gradient(135deg, var(--accent-orange) 0%, var(--accent-yellow) 100%);
  border-color: var(--accent-orange);
  box-shadow: 0 4px 12px rgba(255, 179, 71, 0.35);
}

.difficulty-btn[data-difficulty="hard"].active {
  background: linear-gradient(135deg, var(--accent-red) 0%, var(--accent-pink) 100%);
  border-color: var(--accent-red);
  box-shadow: 0 4px 12px rgba(255, 133, 133, 0.35);
}

/* ===== Badges Grid - OLD (removed) ===== */

/* ===== CENTERED HEADER ===== */
.screen-header-centered {
  display: grid;
  grid-template-columns: 60px 1fr 60px;
  align-items: center;
  width: 100%;
  padding: var(--space-sm) var(--space-md);
  background: rgba(253, 248, 243, 0.85);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-card);
  border: 2px solid rgba(176, 136, 249, 0.1);
  margin-bottom: var(--space-md);
}

.screen-header-centered .screen-title {
  text-align: center;
  margin: 0;
}

.screen-header-centered .btn-back {
  justify-self: start;
}

.header-spacer {
  width: 60px;
}

/* ===== BADGES SCREEN - Complete Redesign ===== */
.badges-screen-content {
  display: flex;
  flex-direction: column;
  max-width: 800px;
  margin: 0 auto;
  width: 100%;
  padding-bottom: var(--space-xl);
}

.badges-summary {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: var(--space-xl) var(--space-md);
  text-align: center;
}

.badges-progress-circle {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  width: 110px;
  height: 110px;
  background: linear-gradient(135deg, #FFFFFF 0%, var(--pastel-yellow) 50%, var(--pastel-orange) 100%);
  border: 4px solid rgba(255, 217, 61, 0.5);
  border-radius: 50%;
  box-shadow: 0 6px 24px rgba(255, 217, 61, 0.3), inset 0 2px 8px rgba(255, 255, 255, 0.5);
  margin-bottom: var(--space-md);
  position: relative;
  overflow: hidden;
}

/* Sparkle effect on badges circle */
.badges-progress-circle::before {
  content: '';
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: linear-gradient(45deg,
      transparent 30%,
      rgba(255, 255, 255, 0.6) 50%,
      transparent 70%);
  animation: badgeSparkle 4s ease-in-out infinite;
  pointer-events: none;
}

.badges-unlocked {
  font-size: var(--font-size-large-title);
  font-weight: 800;
  background: linear-gradient(135deg, var(--accent-orange) 0%, var(--accent-yellow) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  line-height: 1;
  position: relative;
  z-index: 1;
}

.badges-total {
  font-size: var(--font-size-caption1);
  font-weight: 600;
  color: var(--text-secondary);
  position: relative;
  z-index: 1;
}

.badges-motivation {
  font-size: var(--font-size-subhead);
  color: var(--text-secondary);
  margin: 0;
  font-weight: 500;
}

/* Badges Content - By Category */
.badges-content {
  display: flex;
  flex-direction: column;
  gap: var(--space-lg);
  padding: 0 var(--space-md);
}

.badge-category {
  background: linear-gradient(135deg, rgba(255, 255, 255, 0.95) 0%, var(--pastel-lavender) 100%);
  border: 2px solid rgba(176, 136, 249, 0.15);
  border-radius: var(--radius-xxl);
  overflow: hidden;
  box-shadow: var(--shadow-card);
  transition: all var(--transition-fast);
}

.badge-category:hover {
  box-shadow: var(--shadow-md);
}

.badge-category-title {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  padding: var(--space-md) var(--space-lg);
  background: linear-gradient(135deg, rgba(255, 240, 179, 0.3) 0%, rgba(255, 204, 229, 0.3) 100%);
  border-bottom: 2px solid rgba(176, 136, 249, 0.1);
  font-size: var(--font-size-subhead);
  font-weight: 700;
  color: var(--text-primary);
  margin: 0;
}

.badge-category-title .cat-emoji {
  font-size: 1.3rem;
}

.badge-category-title .cat-count {
  margin-left: auto;
  font-size: var(--font-size-caption1);
  font-weight: 600;
  color: var(--accent-purple);
  background: linear-gradient(135deg, var(--pastel-lavender) 0%, var(--pastel-pink) 100%);
  padding: 4px 12px;
  border-radius: var(--radius-pill);
  box-shadow: var(--shadow-sm);
}

.badge-category-items {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(100px, 1fr));
  gap: var(--space-sm);
  padding: var(--space-md);
}

/* Individual Badge Card */
.badge-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  padding: var(--space-md) var(--space-sm);
  border-radius: var(--radius-lg);
  transition: all var(--transition-fast);
  cursor: default;
}

.badge-card:hover {
  background: var(--ios-fill-quaternary);
}

.badge-card .badge {
  width: 56px;
  height: 56px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.75rem;
  background: var(--bg-secondary);
  border-radius: 50%;
  margin-bottom: var(--space-sm);
  transition: all var(--transition-fast);
}

.badge-card .badge.locked {
  filter: grayscale(100%);
  opacity: 0.4;
}

.badge-card .badge-name {
  font-size: var(--font-size-caption1);
  font-weight: 600;
  color: var(--text-primary);
  line-height: 1.3;
  margin-bottom: 2px;
}

.badge-card .badge-desc {
  font-size: var(--font-size-caption2);
  color: var(--text-secondary);
  line-height: 1.3;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

/* Badge unlocked state */
.badge-card:not(.locked) .badge {
  background: linear-gradient(135deg, #FFD700 0%, #FFA500 100%);
  box-shadow: 0 2px 8px rgba(255, 165, 0, 0.3);
}

/* Badge category card - new structure - Playful Style */
.badge-category-card {
  background: linear-gradient(135deg, rgba(255, 255, 255, 0.95) 0%, var(--pastel-lavender) 100%);
  border: 2px solid rgba(176, 136, 249, 0.15);
  border-radius: var(--radius-xxl);
  overflow: hidden;
  box-shadow: var(--shadow-card);
  margin-bottom: var(--space-md);
  transition: all var(--transition-fast);
}

.badge-category-card:hover {
  box-shadow: var(--shadow-md);
}

.badge-category-card .badge-category-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-md) var(--space-lg);
  background: linear-gradient(135deg, rgba(255, 240, 179, 0.3) 0%, rgba(255, 204, 229, 0.3) 100%);
  border-bottom: 2px solid rgba(176, 136, 249, 0.1);
  margin: 0;
}

.badge-category-card .category-title {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.badge-category-card .category-emoji {
  font-size: 1.3rem;
}

.badge-category-card .category-name {
  font-size: var(--font-size-subhead);
  font-weight: 700;
  color: var(--text-primary);
}

.badge-category-card .category-progress {
  font-size: var(--font-size-caption1);
  font-weight: 600;
  color: var(--accent-purple);
  background: linear-gradient(135deg, var(--pastel-lavender) 0%, var(--pastel-pink) 100%);
  padding: 4px 12px;
  border-radius: var(--radius-pill);
  box-shadow: var(--shadow-sm);
}

.badge-category-card .badge-category-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(90px, 1fr));
  gap: var(--space-sm);
  padding: var(--space-md);
  margin: 0;
  background: transparent;
  border-radius: 0;
}

/* Badge category header in old format - keeping for compatibility */
.badge-category-header {
  font-size: var(--font-size-footnote);
  font-weight: 600;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.5px;
  margin-top: var(--space-lg);
  margin-bottom: var(--space-sm);
  padding: 0 var(--space-sm);
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.badge-category-header:first-child {
  margin-top: 0;
}

.badge-category-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(90px, 1fr));
  gap: var(--space-md);
  margin-bottom: var(--space-md);
  background: rgba(255, 255, 255, 0.9);
  border-radius: var(--radius-lg);
  padding: var(--space-md);
}

/* ===== CHARACTERS SYSTEM ===== */
.points-display {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  padding: var(--space-md);
  background: var(--ios-fill);
  border-radius: var(--radius-lg);
  width: fit-content;
}

.points-icon {
  font-size: 1.2rem;
}

.points-value {
  font-size: var(--font-size-title3);
  font-weight: 700;
  color: var(--ios-orange);
  font-variant-numeric: tabular-nums;
}

.points-label {
  font-size: var(--font-size-footnote);
  color: var(--text-secondary);
}

.characters-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--space-md);
}

.character-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: var(--space-md);
  background: var(--bg-primary);
  border: 2px solid var(--ios-separator);
  border-radius: var(--radius-xl);
  cursor: pointer;
  transition: all var(--transition-fast);
  text-align: center;
}

.character-card:active {
  transform: scale(0.98);
}

.character-card.unlocked {
  border-color: var(--ios-blue);
}

.character-card.selected {
  border-color: var(--ios-green);
  background: rgba(52, 199, 89, 0.08);
}

.character-card.locked {
  opacity: 0.7;
  border-color: var(--ios-fill-secondary);
}

.character-card.affordable {
  border-color: var(--ios-orange);
  border-style: dashed;
}

.character-card.affordable:hover {
  background: rgba(255, 149, 0, 0.08);
}

.character-image {
  width: 80px;
  height: 80px;
  object-fit: contain;
  margin-bottom: var(--space-sm);
  border-radius: var(--radius-lg);
}

.character-card.locked .character-image {
  filter: grayscale(80%);
  opacity: 0.6;
}

.character-emoji {
  font-size: 2.5rem;
  margin-bottom: var(--space-sm);
}

.character-name {
  font-size: var(--font-size-footnote);
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: var(--space-xs);
}

.character-status {
  font-size: var(--font-size-caption2);
  color: var(--text-secondary);
}

.character-status.selected {
  color: var(--ios-green);
  font-weight: 600;
}

.character-status {
  font-size: var(--font-size-caption2);
  color: var(--ios-green);
}

.character-cost {
  font-size: var(--font-size-caption2);
  font-weight: 600;
  color: var(--ios-orange);
}

.character-card.locked .character-emoji {
  filter: grayscale(50%);
}

/* ===== DARK MODE BUTTONS - Playful Style ===== */
.dark-mode-options {
  display: flex;
  gap: var(--space-sm);
  justify-content: center;
}

.dark-mode-btn {
  flex: 1;
  min-width: 80px;
  padding: 12px 16px;
  background: linear-gradient(135deg, #FFFFFF 0%, var(--pastel-lavender) 100%);
  border: 2px solid rgba(176, 136, 249, 0.2);
  border-radius: var(--radius-lg);
  font-weight: 600;
  color: var(--text-primary);
  transition: all 0.2s ease;
  box-shadow: var(--shadow-sm);
}

.dark-mode-btn:hover:not(:disabled) {
  border-color: var(--accent-purple);
  box-shadow: var(--shadow-md);
}

.dark-mode-btn:active:not(:disabled) {
  transform: scale(0.97);
}

.dark-mode-btn.active {
  background: linear-gradient(135deg, var(--accent-purple) 0%, var(--accent-pink) 100%);
  border-color: var(--accent-purple);
  color: var(--text-white);
  box-shadow: 0 4px 12px rgba(176, 136, 249, 0.35);
}

/* ===== FRACTIONS DISPLAY ===== */
.fraction {
  display: inline-flex;
  flex-direction: column;
  align-items: center;
  vertical-align: middle;
  font-size: 0.7em;
  line-height: 1.2;
}

.numerator {
  padding-bottom: 2px;
}

.fraction-bar {
  width: 100%;
  min-width: 1.5em;
  height: 3px;
  background: currentColor;
  border-radius: 1px;
}

.denominator {
  padding-top: 2px;
}

/* Fraction in answer display (during input) */
.problem-answer .fraction {
  font-size: 0.85em;
  line-height: 1.1;
}

.problem-answer .fraction .numerator,
.problem-answer .fraction .denominator {
  min-width: 1em;
  text-align: center;
}

.problem-answer .fraction .fraction-bar {
  min-width: 1.2em;
  height: 3px;
  margin: 2px 0;
}

.problem-display.fraction-mode .problem-number {
  font-size: var(--font-size-title1);
}

.problem-display.fraction-mode .fraction {
  font-size: 1em;
}

/* ===== EQUATIONS DISPLAY ===== */
.problem-display.equation-mode .problem-answer {
  background: var(--ios-fill);
  padding: var(--space-xs) var(--space-sm);
  border-radius: var(--radius-sm);
  min-width: 2em;
  text-align: center;
}

.problem-display.equation-mode .problem-number {
  font-weight: 700;
}

.equation-hint {
  color: var(--ios-purple);
  font-style: italic;
  font-weight: 600;
  font-size: 0.9em;
}

/* Choice buttons for fractions */
.choice-btn .fraction {
  font-size: 0.85em;
}

/* ===== PERCENTAGE DISPLAY ===== */
.problem-display.percentage-mode .problem-number {
  font-size: var(--font-size-title1);
}

.problem-display.percentage-mode .problem-operator {
  font-size: var(--font-size-title2);
  color: var(--text-secondary);
  padding: 0 var(--space-xs);
}

/* ===== CONVERSION DISPLAY ===== */
.problem-display.conversion-mode {
  flex-direction: column;
  gap: var(--space-sm);
}

.problem-display.conversion-mode .problem-number {
  font-size: var(--font-size-title2);
  text-align: center;
  line-height: 1.4;
  word-break: break-word;
  max-width: 100%;
}

.problem-display.conversion-mode .problem-operator,
.problem-display.conversion-mode .problem-b,
.problem-display.conversion-mode .problem-equals {
  display: none;
}

/* ===== STARS COUNTER (HOME) ===== */
.stars-counter-home {
  display: inline-flex;
  align-items: center;
  gap: var(--space-xs);
  padding: var(--space-sm) var(--space-md);
  background: linear-gradient(135deg, #FFD700 0%, #FFA500 100%);
  border-radius: var(--radius-pill);
  box-shadow: 0 4px 12px rgba(255, 215, 0, 0.4);
  font-weight: 700;
  color: #5D4600;
  font-size: var(--font-size-body);
}

.stars-counter-home .stars-icon {
  font-size: 1.2em;
}

.stars-counter-home .stars-value {
  min-width: 2ch;
  text-align: center;
}

/* ===== STARS COUNTER (GAME) ===== */
.stars-counter-game {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2xs);
  padding: var(--space-xs) var(--space-sm);
  background: linear-gradient(135deg, #FFD700 0%, #FFA500 100%);
  border-radius: var(--radius-pill);
  box-shadow: 0 2px 8px rgba(255, 215, 0, 0.3);
  font-weight: 700;
  color: #5D4600;
  font-size: var(--font-size-footnote);
}

.stars-counter-game .stars-icon {
  font-size: 1em;
}

.stars-counter-game .stars-value {
  min-width: 2ch;
  text-align: center;
}

/* ===== DAILY CHALLENGE CARD ===== */
.daily-challenge-card {
  width: 100%;
  max-width: 400px;
  padding: var(--space-md);
  background: linear-gradient(135deg, var(--pastel-lavender) 0%, var(--pastel-pink) 100%);
  border: 2px solid rgba(176, 136, 249, 0.3);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-card);
}

.daily-challenge-header {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  margin-bottom: var(--space-sm);
}

.daily-challenge-icon {
  font-size: 1.5rem;
}

.daily-challenge-title {
  font-weight: 700;
  font-size: var(--font-size-subhead);
  color: var(--text-primary);
  flex: 1;
}

.daily-challenge-status {
  font-size: var(--font-size-footnote);
  font-weight: 600;
  padding: var(--space-xs) var(--space-sm);
  border-radius: var(--radius-sm);
}

.daily-challenge-status.completed {
  background: var(--accent-green);
  color: #1a4d2e;
}

.daily-challenge-status.in-progress {
  background: var(--accent-yellow);
  color: #5d4600;
}

.daily-challenge-desc {
  font-size: var(--font-size-subhead);
  color: var(--text-secondary);
  margin-bottom: var(--space-sm);
}

.daily-challenge-progress {
  height: 8px;
  background: rgba(255, 255, 255, 0.5);
  border-radius: var(--radius-pill);
  overflow: hidden;
  margin-bottom: var(--space-xs);
}

.daily-challenge-progress-bar {
  height: 100%;
  background: linear-gradient(90deg, var(--accent-purple) 0%, var(--accent-pink) 100%);
  border-radius: var(--radius-pill);
  transition: width 0.3s ease-out;
}

.daily-challenge-counter {
  text-align: center;
  font-size: var(--font-size-footnote);
  font-weight: 600;
  color: var(--text-secondary);
}

.daily-challenge-card.completed {
  background: linear-gradient(135deg, var(--pastel-green) 0%, #C8FFC8 100%);
  border-color: var(--accent-green);
}

.daily-challenge-card.completed .daily-challenge-progress-bar {
  background: linear-gradient(90deg, var(--accent-green) 0%, #7EEEB4 100%);
}

/* ===== POWER-UPS BAR ===== */
.powerups-bar {
  display: flex;
  justify-content: center;
  gap: var(--space-sm);
  padding: var(--space-sm);
  background: rgba(255, 255, 255, 0.1);
  border-radius: var(--radius-lg);
  margin-bottom: var(--space-md);
}

.powerup-btn {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 2px;
  padding: var(--space-sm);
  min-width: 56px;
  background: linear-gradient(135deg, rgba(255, 255, 255, 0.9) 0%, rgba(255, 255, 255, 0.7) 100%);
  border: 2px solid rgba(176, 136, 249, 0.2);
  border-radius: var(--radius-lg);
  cursor: pointer;
  transition: all 0.2s ease;
  position: relative;
}

.powerup-btn:not(:disabled):hover {
  transform: scale(1.05);
  box-shadow: 0 4px 12px rgba(176, 136, 249, 0.3);
}

.powerup-btn:not(:disabled):active {
  transform: scale(0.95);
}

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

.powerup-btn .powerup-icon {
  font-size: 1.5rem;
}

.powerup-btn .powerup-count {
  font-size: var(--font-size-footnote);
  font-weight: 700;
  color: var(--text-secondary);
}

.powerup-btn .powerup-tooltip {
  display: none;
  position: absolute;
  bottom: -28px;
  left: 50%;
  transform: translateX(-50%);
  white-space: nowrap;
  font-size: var(--font-size-caption2);
  font-weight: 600;
  color: var(--text-primary);
  background: var(--bg-secondary);
  padding: 4px 8px;
  border-radius: var(--radius-sm);
  box-shadow: var(--shadow-sm);
  z-index: 10;
}

.powerup-btn:not(:disabled):hover .powerup-tooltip,
.powerup-btn:not(:disabled):focus .powerup-tooltip {
  display: block;
}

.powerup-btn.active {
  background: linear-gradient(135deg, var(--accent-purple) 0%, var(--accent-pink) 100%);
  border-color: var(--accent-purple);
  animation: pulseScale 1s ease-in-out infinite;
}

.powerup-btn.active .powerup-count {
  color: white;
}

/* Power-up specific colors and glow effects */
.powerup-btn[data-powerup="freezeTime"]:not(:disabled) {
  border-color: rgba(100, 181, 246, 0.5);
  background: linear-gradient(135deg, rgba(100, 181, 246, 0.15) 0%, rgba(255, 255, 255, 0.9) 100%);
  box-shadow: 0 0 12px rgba(100, 181, 246, 0.3);
}

.powerup-btn[data-powerup="freezeTime"]:not(:disabled):hover {
  box-shadow: 0 0 20px rgba(100, 181, 246, 0.5);
  border-color: rgba(100, 181, 246, 0.8);
}

.powerup-btn[data-powerup="doublePoints"]:not(:disabled) {
  border-color: rgba(255, 215, 0, 0.5);
  background: linear-gradient(135deg, rgba(255, 215, 0, 0.15) 0%, rgba(255, 255, 255, 0.9) 100%);
  box-shadow: 0 0 12px rgba(255, 215, 0, 0.3);
}

.powerup-btn[data-powerup="doublePoints"]:not(:disabled):hover {
  box-shadow: 0 0 20px rgba(255, 215, 0, 0.5);
  border-color: rgba(255, 215, 0, 0.8);
}

.powerup-btn[data-powerup="extraLife"]:not(:disabled) {
  border-color: rgba(255, 105, 180, 0.5);
  background: linear-gradient(135deg, rgba(255, 105, 180, 0.15) 0%, rgba(255, 255, 255, 0.9) 100%);
  box-shadow: 0 0 12px rgba(255, 105, 180, 0.3);
}

.powerup-btn[data-powerup="extraLife"]:not(:disabled):hover {
  box-shadow: 0 0 20px rgba(255, 105, 180, 0.5);
  border-color: rgba(255, 105, 180, 0.8);
}

.powerup-btn[data-powerup="hint"]:not(:disabled) {
  border-color: rgba(255, 179, 71, 0.5);
  background: linear-gradient(135deg, rgba(255, 179, 71, 0.15) 0%, rgba(255, 255, 255, 0.9) 100%);
  box-shadow: 0 0 12px rgba(255, 179, 71, 0.3);
}

.powerup-btn[data-powerup="hint"]:not(:disabled):hover {
  box-shadow: 0 0 20px rgba(255, 179, 71, 0.5);
  border-color: rgba(255, 179, 71, 0.8);
}

/* Double points active indicator */
.double-points-active {
  position: fixed;
  top: 80px;
  right: 20px;
  padding: var(--space-xs) var(--space-sm);
  background: linear-gradient(135deg, #FFD700 0%, #FFA500 100%);
  border-radius: var(--radius-pill);
  font-weight: 700;
  font-size: var(--font-size-footnote);
  color: #5D4600;
  z-index: 100;
  animation: pulseScale 0.5s ease-in-out infinite;
}

/* Freeze time overlay effect */
.freeze-overlay {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(100, 200, 255, 0.1);
  pointer-events: none;
  z-index: 50;
  animation: fadeIn 0.3s ease-out;
}

.freeze-overlay::before {
  content: '❄️ TEMPS GELÉ';
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  font-size: var(--font-size-title1);
  font-weight: 700;
  color: #64B5F6;
  text-shadow: 0 2px 10px rgba(100, 181, 246, 0.5);
}

/* ===== Mascot Speech Bubble ===== */
.mascot-bubble {
  position: absolute;
  background: white;
  border-radius: 18px;
  padding: 12px 18px;
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
  max-width: 180px;
  z-index: 10;
  bottom: 85%;
  left: 50%;
  transform: translateX(-50%) scale(0);
  transition: transform 0.3s cubic-bezier(0.175, 0.885, 0.32, 1.275);
  pointer-events: none;
}

.mascot-bubble.active {
  transform: translateX(-50%) scale(1);
}

.bubble-text {
  font-family: var(--font-display);
  font-size: 14px;
  font-weight: 500;
  color: #333;
  line-height: 1.3;
  text-align: center;
}

.bubble-tail {
  position: absolute;
  bottom: -8px;
  left: 50%;
  transform: translateX(-50%);
  width: 0;
  height: 0;
  border-left: 8px solid transparent;
  border-right: 8px solid transparent;
  border-top: 8px solid white;
}

html.dark-mode .mascot-bubble {
  background: #2a2a3a;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.4);
  border: 1px solid rgba(255, 255, 255, 0.1);
}

html.dark-mode .bubble-text {
  color: #eee;
}

html.dark-mode .bubble-tail {
  border-top-color: #2a2a3a;
}

/* Home mascot specific position */
.home-mascot .mascot-bubble {
  bottom: 90%;
  max-width: 220px;
}

/* ===== MANUAL DARK MODE CLASSES ===== */
html.dark-mode {
  color-scheme: dark;

  /* Dark mode variables - Warm dark theme */
  --bg-primary: #1A1A24;
  --bg-secondary: #12121A;
  --bg-grouped: #12121A;
  --bg-tertiary: #242432;

  --text-primary: #FFFFFF;
  --text-secondary: rgba(235, 235, 245, 0.85);
  --text-tertiary: rgba(235, 235, 245, 0.55);
  --text-quaternary: rgba(235, 235, 245, 0.3);

  --ios-fill: rgba(140, 140, 160, 0.25);
  --ios-fill-secondary: rgba(140, 140, 160, 0.2);
  --ios-fill-tertiary: rgba(140, 140, 160, 0.15);
  --ios-fill-quaternary: rgba(140, 140, 160, 0.1);

  --ios-separator: rgba(100, 100, 120, 0.3);
  --ios-separator-opaque: #38384A;

  --shadow-card: 0 2px 8px rgba(0, 0, 0, 0.4), 0 4px 16px rgba(176, 136, 249, 0.1);
  --shadow-elevated: 0 6px 20px rgba(0, 0, 0, 0.5);

  /* Dark mode gradients - More vibrant and depth */
  --gradient-home: linear-gradient(135deg, #1A1A2E 0%, #2D1B4E 50%, #16213E 100%);
  --gradient-game: linear-gradient(135deg, #1A2A2E 0%, #2A2040 50%, #162431 100%);
  --gradient-badges: linear-gradient(135deg, #2A2A1E 0%, #3D2B5E 50%, #1A2129 100%);
  --gradient-settings: linear-gradient(135deg, #2D1B3E 0%, #152238 100%);

  /* Keep accent colors vibrant in dark mode */
  --accent-purple: #C4A8FF;
  --accent-pink: #FF9FC4;
  --accent-blue: #7CC5FF;
  --accent-green: #7EEEB4;
  --accent-yellow: #FFE066;
  --accent-orange: #FFC466;
  --accent-red: #FF9999;
}

html.dark-mode body {
  background-color: var(--bg-primary);
  color: var(--text-primary);
}

html.light-mode {
  color-scheme: light;

  /* Explicit Light Mode Variables - Warm and friendly */
  --bg-primary: #FFFEF8;
  --bg-secondary: #FDF8F3;
  --bg-tertiary: #FFFEF8;
  --bg-grouped: #FDF8F3;
  --bg-grouped-secondary: #FFFEF8;

  --text-primary: #2D2D3A;
  --text-secondary: rgba(45, 45, 58, 0.65);
  --text-tertiary: rgba(45, 45, 58, 0.4);
  --text-quaternary: rgba(45, 45, 58, 0.2);

  --ios-fill: rgba(140, 140, 160, 0.15);
  --ios-fill-secondary: rgba(140, 140, 160, 0.12);
  --ios-fill-tertiary: rgba(140, 140, 160, 0.08);
  --ios-fill-quaternary: rgba(140, 140, 160, 0.05);

  --ios-separator: rgba(100, 100, 120, 0.1);
  --ios-separator-opaque: #E0E0E8;

  --shadow-card: 0 2px 8px rgba(176, 136, 249, 0.1), 0 4px 16px rgba(255, 143, 177, 0.08);
  --shadow-elevated: 0 6px 20px rgba(176, 136, 249, 0.25);

  /* Playful light mode gradients */
  --gradient-home: linear-gradient(135deg, #FFF9E6 0%, #FFE4EC 50%, #E8F4FF 100%);
  --gradient-game: linear-gradient(135deg, #E8F8F0 0%, #FFF5E6 50%, #F0E8FF 100%);
  --gradient-badges: linear-gradient(135deg, #FFF0B3 0%, #FFCCE5 50%, #B8E4FF 100%);
  --gradient-settings: linear-gradient(135deg, #F5E6FF 0%, #E6F5FF 100%);
}

/* Light mode specific overrides */
html.light-mode .card {
  background: rgba(255, 255, 255, 0.95);
}

html.light-mode .home-stats {
  background: rgba(255, 255, 255, 0.95);
}

html.light-mode .screen-header-fixed,
html.light-mode .screen-header-centered {
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-color: rgba(176, 136, 249, 0.15);
}

html.light-mode .btn-secondary-action {
  background: rgba(255, 255, 255, 0.95);
  color: var(--text-primary);
}

html.light-mode .numpad-btn {
  background: var(--bg-primary);
  color: var(--text-primary);
}

html.light-mode .choice-btn {
  background: var(--bg-primary);
  color: var(--text-primary);
}

html.light-mode .problem-display {
  background: var(--bg-primary);
}

html.light-mode .toggle-slider {
  background-color: #E9E9EB;
}

html.light-mode .badges-progress-circle {
  background: rgba(255, 255, 255, 0.9);
}

html.light-mode .badge-category-card {
  background: rgba(255, 255, 255, 0.95);
}

html.light-mode .badge-category-grid {
  background: rgba(255, 255, 255, 0.9);
}

/* Dark mode screen backgrounds */
html.dark-mode .screen,
html.dark-mode #home-screen,
html.dark-mode #mode-screen,
html.dark-mode #results-screen {
  background: var(--gradient-home);
}

html.dark-mode #settings-screen {
  background: var(--gradient-settings);
}

html.dark-mode #badges-screen {
  background: var(--gradient-badges);
}

html.dark-mode #game-screen {
  background: var(--gradient-game);
}

/* Dark mode card styles */
html.dark-mode .card {
  background: rgba(44, 44, 46, 0.9);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
}

/* Dark mode home stats - Improved readability */
html.dark-mode .home-stats {
  background: linear-gradient(135deg, rgba(44, 44, 60, 0.95) 0%, rgba(60, 50, 80, 0.9) 100%);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: 2px solid rgba(176, 136, 249, 0.3);
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3), 0 0 0 1px rgba(255, 255, 255, 0.05);
}

html.dark-mode .stats-card-title {
  color: rgba(255, 255, 255, 0.8);
  text-shadow: 0 1px 2px rgba(0, 0, 0, 0.3);
}

html.dark-mode .stat-number {
  color: #FFFFFF;
  text-shadow: 0 2px 4px rgba(0, 0, 0, 0.3);
}

html.dark-mode .stat-desc {
  color: rgba(255, 255, 255, 0.9);
}

html.dark-mode .stat-icon {
  filter: drop-shadow(0 2px 4px rgba(0, 0, 0, 0.3));
}

html.dark-mode .stat-divider {
  background: rgba(255, 255, 255, 0.2);
}

html.dark-mode .xp-value {
  color: var(--accent-purple);
  text-shadow: 0 0 10px rgba(196, 168, 255, 0.5);
}

html.dark-mode .xp-label {
  color: rgba(255, 255, 255, 0.9);
}

/* Dark mode home subtitle */
html.dark-mode .home-subtitle {
  color: rgba(255, 255, 255, 0.95);
  text-shadow: 0 1px 2px rgba(0, 0, 0, 0.5);
}

/* Dark mode title glow effects */
html.dark-mode .title-super {
  text-shadow: 0 0 20px rgba(255, 196, 102, 0.5), 0 2px 4px rgba(0, 0, 0, 0.3);
}

html.dark-mode .home-title {
  filter: drop-shadow(0 4px 8px rgba(0, 0, 0, 0.3));
}

/* Dark mode buttons */
html.dark-mode .btn-outline {
  border-color: var(--ios-separator);
  color: var(--text-primary);
  background: rgba(44, 44, 46, 0.6);
}

html.dark-mode .btn-secondary-action {
  background: linear-gradient(135deg, rgba(60, 60, 80, 0.9) 0%, rgba(50, 50, 70, 0.9) 100%);
  color: #FFFFFF;
  border: 1px solid rgba(176, 136, 249, 0.3);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
}

html.dark-mode .btn-secondary-action:hover {
  background: linear-gradient(135deg, rgba(70, 70, 100, 0.95) 0%, rgba(60, 60, 85, 0.95) 100%);
  border-color: rgba(176, 136, 249, 0.5);
}

html.dark-mode .btn-secondary-action .btn-icon-small {
  filter: drop-shadow(0 2px 4px rgba(0, 0, 0, 0.3));
}

/* Dark mode modals */
html.dark-mode .modal {
  background: var(--bg-secondary);
}

html.dark-mode .modal-overlay {
  background: rgba(0, 0, 0, 0.7);
}

/* Dark mode game elements */
html.dark-mode .numpad-btn {
  background: rgba(44, 44, 46, 0.9);
  color: var(--text-primary);
}

html.dark-mode .choice-btn {
  background: rgba(44, 44, 46, 0.9);
  color: var(--text-primary);
}

html.dark-mode .problem-display {
  background: rgba(44, 44, 46, 0.9);
}

/* Dark mode navigation */
html.dark-mode .header-bar,
html.dark-mode .ios-nav,
html.dark-mode .screen-header-fixed,
html.dark-mode .screen-header-centered {
  background: rgba(28, 28, 30, 0.8);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-color: rgba(255, 255, 255, 0.1);
}

/* Dark mode characters */
html.dark-mode .character-card {
  background: rgba(44, 44, 46, 0.9);
}

html.dark-mode .character-card.selected {
  background: rgba(52, 199, 89, 0.2);
}

html.dark-mode .character-card.affordable {
  background: rgba(255, 149, 0, 0.2);
}

/* Dark mode badges */
html.dark-mode .badges-progress-circle {
  background: rgba(44, 44, 46, 0.9);
}

html.dark-mode .badge-category {
  background: rgba(44, 44, 46, 0.9);
}

html.dark-mode .badge-category-card {
  background: rgba(44, 44, 46, 0.95);
  box-shadow: 0 2px 12px rgba(0, 0, 0, 0.3);
}

html.dark-mode .badge-category-card .badge-category-header {
  background: rgba(0, 0, 0, 0.2);
  border-color: rgba(255, 255, 255, 0.1);
}

html.dark-mode .badge-category-card .category-name {
  color: var(--text-primary);
}

html.dark-mode .badge-category-card .category-progress {
  background: rgba(255, 255, 255, 0.1);
}

html.dark-mode .badge-category-title {
  background: rgba(0, 0, 0, 0.2);
  border-color: rgba(255, 255, 255, 0.1);
}

html.dark-mode .badge-category-grid {
  background: rgba(44, 44, 46, 0.9);
}

html.dark-mode .badge-card .badge {
  background: rgba(60, 60, 67, 0.6);
}

html.dark-mode .badge-card:not(.locked) .badge {
  background: linear-gradient(135deg, #FFD700 0%, #FFA500 100%);
}

/* Dark mode mode cards */
html.dark-mode .mode-card {
  background: rgba(44, 44, 46, 0.9);
}

/* Dark mode toggle slider */
html.dark-mode .toggle-slider {
  background-color: #39393D;
}

/* Dark mode progress bar - Enhanced visibility */
html.dark-mode .progress.xp-bar {
  background: rgba(255, 255, 255, 0.15);
  border: 1px solid rgba(255, 255, 255, 0.1);
}

html.dark-mode .progress.xp-bar .progress-bar {
  background: linear-gradient(90deg, var(--accent-purple) 0%, var(--accent-pink) 100%);
  box-shadow: 0 0 10px rgba(196, 168, 255, 0.5);
}

/* Dark mode title colors stay vibrant - use gradients */
html.dark-mode .title-super {
  color: var(--accent-orange);
}

html.dark-mode .title-maths {
  background: linear-gradient(135deg, var(--accent-blue) 0%, var(--accent-purple) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

html.dark-mode .title-hero {
  background: linear-gradient(135deg, var(--accent-purple) 0%, var(--accent-pink) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* Dark mode play button */
html.dark-mode .btn-play {
  background: linear-gradient(135deg, var(--accent-purple) 0%, var(--accent-pink) 50%, var(--accent-yellow) 100%);
  box-shadow: 0 6px 20px rgba(196, 168, 255, 0.4);
}

/* Dark mode cards */
html.dark-mode .mode-card {
  background: rgba(36, 36, 50, 0.9);
  border-color: rgba(176, 136, 249, 0.2);
}

html.dark-mode .mode-card.card-success {
  background: linear-gradient(135deg, rgba(36, 36, 50, 0.95) 0%, rgba(126, 238, 180, 0.15) 100%);
}

html.dark-mode .mode-card.card-hero {
  background: linear-gradient(135deg, rgba(36, 36, 50, 0.95) 0%, rgba(124, 197, 255, 0.15) 100%);
}

html.dark-mode .mode-card.card-primary {
  background: linear-gradient(135deg, rgba(36, 36, 50, 0.95) 0%, rgba(255, 196, 102, 0.15) 100%);
}

/* Dark mode problem display */
html.dark-mode .problem-display {
  background: linear-gradient(135deg, rgba(36, 36, 50, 0.95) 0%, rgba(176, 136, 249, 0.1) 50%, rgba(126, 238, 180, 0.1) 100%);
  border-color: rgba(176, 136, 249, 0.3);
}

/* Dark mode choice buttons */
html.dark-mode .choice-btn {
  background: linear-gradient(135deg, rgba(36, 36, 50, 0.95) 0%, rgba(176, 136, 249, 0.1) 100%);
  border-color: rgba(176, 136, 249, 0.3);
}

/* Dark mode stats card */
html.dark-mode .home-stats {
  background: linear-gradient(135deg, rgba(36, 36, 50, 0.95) 0%, rgba(255, 224, 102, 0.1) 100%);
  border-color: rgba(255, 224, 102, 0.3);
}

/* Dark mode combo messages */
html.dark-mode .combo-message {
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.5);
}

/* Dark mode operation checkboxes */
html.dark-mode .operation-checkbox {
  background: linear-gradient(135deg, rgba(36, 36, 50, 0.95) 0%, rgba(176, 136, 249, 0.15) 100%);
  border-color: rgba(176, 136, 249, 0.3);
}

html.dark-mode .operation-checkbox:hover {
  border-color: rgba(176, 136, 249, 0.5);
}

html.dark-mode .operation-label {
  color: var(--text-primary);
}

/* Dark mode operation checkbox checked states with proper text colors */
html.dark-mode .operation-checkbox:has(.operation-input:checked) {
  background: linear-gradient(135deg, rgba(102, 222, 147, 0.25) 0%, rgba(126, 238, 180, 0.15) 100%);
  border-color: var(--accent-green);
}

html.dark-mode .operation-checkbox[data-op="+"]:has(.operation-input:checked) {
  background: linear-gradient(135deg, rgba(102, 222, 147, 0.25) 0%, rgba(126, 238, 180, 0.15) 100%);
  border-color: var(--accent-green);
}

html.dark-mode .operation-checkbox[data-op="-"]:has(.operation-input:checked) {
  background: linear-gradient(135deg, rgba(255, 153, 153, 0.25) 0%, rgba(255, 133, 133, 0.15) 100%);
  border-color: var(--accent-red);
}

html.dark-mode .operation-checkbox[data-op="×"]:has(.operation-input:checked) {
  background: linear-gradient(135deg, rgba(124, 197, 255, 0.25) 0%, rgba(100, 181, 246, 0.15) 100%);
  border-color: var(--accent-blue);
}

html.dark-mode .operation-checkbox[data-op="÷"]:has(.operation-input:checked) {
  background: linear-gradient(135deg, rgba(255, 196, 102, 0.25) 0%, rgba(255, 179, 71, 0.15) 100%);
  border-color: var(--accent-orange);
}

html.dark-mode .operation-checkbox[data-op="½"]:has(.operation-input:checked) {
  background: linear-gradient(135deg, rgba(255, 159, 196, 0.25) 0%, rgba(255, 143, 177, 0.15) 100%);
  border-color: var(--accent-pink);
}

html.dark-mode .operation-checkbox[data-op="x"]:has(.operation-input:checked) {
  background: linear-gradient(135deg, rgba(196, 168, 255, 0.25) 0%, rgba(176, 136, 249, 0.15) 100%);
  border-color: var(--accent-purple);
}

/* Dark mode daily challenge - Enhanced readability */
html.dark-mode .daily-challenge-card {
  background: linear-gradient(135deg, rgba(30, 25, 45, 0.98) 0%, rgba(45, 35, 65, 0.95) 100%);
  border: 2px solid rgba(176, 136, 249, 0.4);
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.5), 0 0 0 1px rgba(255, 255, 255, 0.1);
}

html.dark-mode .daily-challenge-card.completed {
  background: linear-gradient(135deg, rgba(40, 60, 50, 0.95) 0%, rgba(50, 80, 60, 0.9) 100%);
  border-color: var(--accent-green);
}

html.dark-mode .daily-challenge-header {
  color: #FFFFFF;
}

html.dark-mode .daily-challenge-title {
  color: #FFFFFF;
  text-shadow: 0 1px 3px rgba(0, 0, 0, 0.3);
}

html.dark-mode .daily-challenge-desc {
  color: rgba(255, 255, 255, 0.95);
}

html.dark-mode .daily-challenge-counter {
  color: rgba(255, 255, 255, 0.9);
}

html.dark-mode .daily-challenge-progress {
  background: rgba(255, 255, 255, 0.15);
  border: 1px solid rgba(255, 255, 255, 0.1);
}

html.dark-mode .daily-challenge-progress-bar {
  box-shadow: 0 0 8px rgba(196, 168, 255, 0.5);
}

html.dark-mode .daily-challenge-status.in-progress {
  background: rgba(255, 217, 61, 0.9);
  color: #4a3c00;
}

html.dark-mode .daily-challenge-status.completed {
  background: rgba(126, 238, 180, 0.9);
  color: #1a4d2e;
}

/* Dark mode power-ups */
html.dark-mode .powerups-bar {
  background: rgba(0, 0, 0, 0.2);
}

html.dark-mode .powerup-btn {
  background: linear-gradient(135deg, rgba(44, 44, 46, 0.9) 0%, rgba(60, 60, 67, 0.8) 100%);
  border-color: rgba(176, 136, 249, 0.2);
}

html.dark-mode .powerup-btn:not(:disabled):hover {
  border-color: rgba(176, 136, 249, 0.5);
}

html.dark-mode .powerup-btn .powerup-count {
  color: var(--text-secondary);
}

/* Dark mode stars counter - Enhanced glow */
html.dark-mode .stars-counter-home,
html.dark-mode .stars-counter-game {
  background: linear-gradient(135deg, #FFD700 0%, #FFA500 100%);
  color: #5D4600;
  box-shadow: 0 4px 16px rgba(255, 215, 0, 0.5), 0 0 30px rgba(255, 215, 0, 0.3);
}

/* Dark mode mascot enhancement */
html.dark-mode .mascot-img {
  filter: drop-shadow(0 8px 24px rgba(176, 136, 249, 0.4)) drop-shadow(0 0 40px rgba(176, 136, 249, 0.2));
}

/* Dark mode home container */
html.dark-mode .home-container {
  position: relative;
}

/* Subtle ambient glow behind content in dark mode */
html.dark-mode #home-screen::before {
  content: '';
  position: absolute;
  top: 20%;
  left: 50%;
  transform: translateX(-50%);
  width: 80%;
  height: 60%;
  background: radial-gradient(ellipse at center, rgba(176, 136, 249, 0.15) 0%, transparent 70%);
  pointer-events: none;
  z-index: 0;
}

html.dark-mode #home-screen>* {
  position: relative;
  z-index: 1;
}

/* ===== INLINE STYLE REPLACEMENTS ===== */

/* Settings helper text */
.settings-helper-text {
  margin-bottom: var(--space-md);
  color: var(--color-text-light);
}

/* Select-all button spacing */
.btn-select-all {
  margin-top: var(--space-md);
}

/* Slider display layout */
.slider-display {
  align-items: center;
  margin-bottom: var(--space-md);
}

/* Slider labels */
.slider-labels {
  margin-top: var(--space-sm);
}

/* Input method buttons */
.input-method-btn {
  flex: 1;
}

/* Points display spacing */
.points-display {
  margin-bottom: var(--space-md);
}

/* Game header spacing */
.game-header {
  margin-bottom: var(--space-lg);
}

/* Streak container spacing */
.streak-container {
  margin-bottom: var(--space-md);
}

/* Mascot feedback area */
.mascot-feedback {
  text-align: center;
  margin: var(--space-md) 0;
  position: relative;
}

/* Game mascot image */
.mascot-game-img {
  max-width: 120px;
  height: auto;
}

/* Input area layout */
.input-area {
  flex: 1;
  display: flex;
  flex-direction: column;
  justify-content: center;
}

/* Game controls spacing */
.game-controls {
  margin-top: var(--space-lg);
}

/* Game control buttons */
.game-control-btn {
  flex: 1;
}

/* Result header spacing */
.result-header {
  margin-bottom: var(--space-xl);
}

/* Result title size */
.result-title {
  font-size: var(--font-size-xxxl);
}

/* Result image */
.result-img {
  max-width: 200px;
  height: auto;
  margin: var(--space-md) auto;
}

/* Result message */
.result-message {
  margin-top: var(--space-md);
  font-size: var(--font-size-lg);
}

/* Stats grid layout */
.stats-grid {
  justify-content: center;
  margin-bottom: var(--space-xl);
}

/* New badges section spacing */
.new-badges-section {
  margin-bottom: var(--space-xl);
}

/* New badges title */
.new-badges-title {
  margin-bottom: var(--space-md);
}

/* New badges list */
.new-badges-list {
  justify-content: center;
}

/* Result actions container */
.result-actions {
  width: 100%;
  max-width: 300px;
}

/* Offline banner */
.offline-banner {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 9999;
  background: var(--color-warning, #FF9800);
  color: #fff;
  text-align: center;
  padding: 6px 16px;
  font-size: var(--font-size-sm);
  font-weight: 600;
  transition: transform 0.3s ease;
}

.offline-banner.hidden {
  transform: translateY(-100%);
}

/* SW update toast */
.sw-update-toast {
  cursor: pointer;
}