/* Design Tokens & Theme Variables */
:root {
  --font-serif: 'Source Serif 4', Georgia, serif;
  --font-sans: 'Source Sans 3', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  
  /* Light Theme Colors */
  --bg: #f8fafc;
  --surface: #ffffff;
  --surface-hover: #f1f5f9;
  --surface-active: #e2e8f0;
  
  --ink: #0f172a;
  --ink-secondary: #475569;
  --ink-tertiary: #94a3b8;
  
  --primary: #3b82f6;
  --primary-hover: #2563eb;
  --primary-bg: #eff6ff;
  
  --success: #10b981;
  --success-hover: #059669;
  --success-bg: #ecfdf5;
  --success-border: #a7f3d0;
  
  --danger: #ef4444;
  --danger-hover: #dc2626;
  --danger-bg: #fef2f2;
  --danger-border: #fca5a5;
  
  --warning: #f59e0b;
  --warning-bg: #fffbeb;
  
  --border: #e2e8f0;
  --border-focus: #3b82f6;
  
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.08), 0 2px 4px -1px rgba(0, 0, 0, 0.04);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
  
  --radius: 16px;
  --radius-sm: 8px;
  
  --transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
}

/* Dark Theme Colors */
body.dark-theme {
  --bg: #090d16;
  --surface: #131b2e;
  --surface-hover: #1e294b;
  --surface-active: #243565;
  
  --ink: #f8fafc;
  --ink-secondary: #cbd5e1;
  --ink-tertiary: #64748b;
  
  --primary: #3b82f6;
  --primary-hover: #60a5fa;
  --primary-bg: rgba(59, 130, 246, 0.15);
  
  --success: #34d399;
  --success-hover: #5eead4;
  --success-bg: rgba(52, 211, 153, 0.1);
  --success-border: rgba(52, 211, 153, 0.3);
  
  --danger: #f87171;
  --danger-hover: #fca5a5;
  --danger-bg: rgba(248, 113, 113, 0.1);
  --danger-border: rgba(248, 113, 113, 0.3);
  
  --warning: #fbbf24;
  --warning-bg: rgba(251, 191, 36, 0.1);
  
  --border: #1e293b;
  --border-focus: #60a5fa;
  
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.5);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.3);
  --shadow-lg: 0 20px 25px -5px rgba(0, 0, 0, 0.4);
}

/* Global Reset & Viewport Locking */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: var(--font-sans);
  background: linear-gradient(135deg, #f1f5f9 0%, #cbd5e1 100%); /* Softer, pleasant light gray-blue background */
  color: var(--ink);
  height: 100vh;
  overflow: hidden;
  transition: background 0.3s ease;
}

body.dark-theme {
  background: linear-gradient(135deg, #1e293b 0%, #0f172a 100%); /* Soft eye-pleasing slate dark gradient */
}

#app {
  width: 100%;
  height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
}

/* App Container (Centered spacious desktop view, fluid mobile view) */
.app-container {
  width: 100%;
  max-width: 820px; /* Spacious width for all views */
  height: 100vh;
  display: flex;
  flex-direction: column;
  background-color: var(--bg);
  position: relative;
  transition: var(--transition);
  box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.5);
}

@media (min-width: 821px) {
  .app-container {
    height: 92vh;
    border-radius: var(--radius);
    border: 1px solid var(--border);
    overflow: hidden;
  }
}

/* Top App Header (Anchored) */
.app-header {
  background-color: var(--surface);
  border-bottom: 1px solid var(--border);
  padding: 16px 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  z-index: 100;
  flex-shrink: 0;
}

.header-brand h1 {
  font-family: 'Outfit', var(--font-sans);
  font-size: 1.3rem;
  font-weight: 800;
  letter-spacing: -0.01em;
  color: var(--ink);
}

.header-brand p {
  font-size: 0.78rem;
  color: var(--ink-secondary);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 12px;
}

/* Independent Scroll View Content Area */
.view-content {
  flex: 1;
  overflow-y: auto;
  padding: 24px 24px;
  background-color: var(--bg);
  -webkit-overflow-scrolling: touch;
}

/* Custom Scrollbar for independent scroll pane */
.view-content::-webkit-scrollbar {
  width: 6px;
}
.view-content::-webkit-scrollbar-track {
  background: transparent;
}
.view-content::-webkit-scrollbar-thumb {
  background-color: var(--border);
  border-radius: 999px;
}

/* Sticky Bottom Navigation Tab Bar */
.bottom-nav {
  display: flex;
  background-color: var(--surface);
  border-top: 1px solid var(--border);
  padding: 10px 24px 14px 24px;
  z-index: 100;
  flex-shrink: 0;
  box-shadow: 0 -4px 12px rgba(0, 0, 0, 0.02);
}

.bottom-tab-btn {
  flex: 1;
  border: none;
  background: none;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 4px;
  color: var(--ink-tertiary);
  cursor: pointer;
  font-family: inherit;
  font-size: 0.78rem;
  font-weight: 700;
  transition: var(--transition);
  padding: 4px 0;
  border-radius: var(--radius-sm);
}

.bottom-tab-btn:hover {
  color: var(--ink-secondary);
}

.bottom-tab-btn.active {
  color: var(--primary);
}

.bottom-tab-btn .app-icon {
  width: 22px;
  height: 22px;
  stroke-width: 2.2;
}

.bottom-tab-btn.active .app-icon {
  transform: scale(1.05);
}

/* Vector SVG Icon style */
.app-icon {
  display: inline-block;
  vertical-align: middle;
  width: 1.25rem;
  height: 1.25rem;
  stroke: currentColor;
  fill: none;
  stroke-linecap: round;
  stroke-linejoin: round;
  flex-shrink: 0;
  transition: var(--transition);
}

/* General Layout Cards */
.premium-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  box-shadow: var(--shadow-sm);
  margin-bottom: 20px;
  position: relative;
  transition: var(--transition);
}

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

/* Membership Indicator Badge */
.membership-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 12px;
  border-radius: 9999px;
  font-size: 0.72rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  cursor: pointer;
  transition: var(--transition);
}

.membership-badge.free {
  background-color: var(--surface-hover);
  border: 1px solid var(--border);
  color: var(--ink-secondary);
}

.membership-badge.premium {
  background: linear-gradient(135deg, #fbbf24 0%, #d97706 100%);
  color: #fff;
  border: 1px solid rgba(255, 255, 255, 0.15);
}

.membership-badge:hover {
  transform: scale(1.03);
}

/* Theme controller button */
.theme-toggle {
  background: transparent;
  border: 1px solid var(--border);
  color: var(--ink-secondary);
  width: 34px;
  height: 34px;
  border-radius: 50%;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: var(--transition);
}

.theme-toggle:hover {
  background-color: var(--surface-hover);
  transform: rotate(15deg);
}

/* Stats dashboard blocks */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
  margin-bottom: 20px;
}

.stat-box {
  background-color: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 18px 12px;
  text-align: center;
  box-shadow: var(--shadow-sm);
  transition: var(--transition);
}

.stat-box:hover {
  border-color: var(--primary);
}

.stat-value {
  font-family: 'Outfit', var(--font-sans);
  font-size: 1.8rem;
  font-weight: 800;
  color: var(--primary);
  line-height: 1.2;
}

.stat-label {
  font-size: 0.72rem;
  color: var(--ink-secondary);
  text-transform: uppercase;
  letter-spacing: 0.04em;
  margin-top: 4px;
}

/* Action grid - adapts width dynamically */
.dashboard-actions {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 12px;
  margin-bottom: 20px;
}

@media (max-width: 480px) {
  .dashboard-actions {
    grid-template-columns: 1fr;
  }
}

.action-tile {
  background-color: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px;
  cursor: pointer;
  transition: var(--transition);
  display: flex;
  flex-direction: column;
  gap: 4px;
  box-shadow: var(--shadow-sm);
}

.action-tile:hover {
  border-color: var(--primary);
  background-color: var(--surface-hover);
  transform: translateY(-2px);
}

.action-title {
  font-size: 0.95rem;
  font-weight: 800;
  color: var(--ink);
  display: flex;
  align-items: center;
  gap: 8px;
}

.action-desc {
  font-size: 0.8rem;
  color: var(--ink-secondary);
  line-height: 1.4;
}

/* Lock label indicators */
.locked-feature-indicator {
  display: inline-flex;
  align-items: center;
  gap: 3px;
  font-size: 0.6rem;
  font-weight: 800;
  background-color: var(--warning-bg);
  color: var(--warning);
  padding: 1px 6px;
  border-radius: 9999px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-left: auto;
}

/* Categories page components - Responsive columns */
.categories-header {
  margin-bottom: 16px;
}

.search-wrapper {
  margin-bottom: 16px;
}

.search-input {
  width: 100%;
  padding: 12px 16px;
  background-color: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--ink);
  font-family: inherit;
  font-size: 0.9rem;
  outline: none;
  transition: var(--transition);
}

.search-input:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.12);
}

.categories-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 12px;
}

@media (max-width: 580px) {
  .categories-grid {
    grid-template-columns: 1fr;
  }
}

.category-card {
  background-color: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 16px 20px;
  cursor: pointer;
  transition: var(--transition);
  display: flex;
  align-items: center;
  position: relative;
  box-shadow: var(--shadow-sm);
}

.category-card:hover {
  border-color: var(--primary);
  background-color: var(--surface-hover);
}

.category-info {
  flex: 1;
  padding-right: 12px;
}

.category-title {
  font-size: 0.92rem;
  font-weight: 700;
  color: var(--ink);
}

.category-count {
  font-size: 0.78rem;
  color: var(--ink-secondary);
}

.category-progress-container {
  width: 80px;
  margin-left: auto;
}

.progress-bar-bg {
  height: 6px;
  background-color: var(--border);
  border-radius: 999px;
  overflow: hidden;
}

.progress-bar-fill {
  height: 100%;
  background-color: var(--success);
  border-radius: 999px;
  transition: width 0.4s ease;
}

.category-lock-badge {
  color: var(--warning);
  margin-left: 12px;
  display: flex;
  align-items: center;
}

/* Practice screen navigation */
.back-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  color: var(--primary);
  font-size: 0.88rem;
  font-weight: 700;
  text-decoration: none;
  cursor: pointer;
  margin-bottom: 16px;
  transition: var(--transition);
}

.back-link:hover {
  transform: translateX(-2px);
}

.progress-tracker {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 16px;
}

.progress-bar-wrapper {
  flex: 1;
  height: 8px;
  background-color: var(--border);
  border-radius: 999px;
  overflow: hidden;
}

.progress-bar-fill-indicator {
  height: 100%;
  background-color: var(--primary);
  border-radius: 999px;
  transition: width 0.3s ease;
}

.progress-text {
  font-size: 0.8rem;
  color: var(--ink-secondary);
  font-weight: 700;
}

.question-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-bottom: 1px solid var(--border);
  padding-bottom: 12px;
  margin-bottom: 16px;
}

.question-category {
  font-size: 0.8rem;
  font-weight: 800;
  color: var(--ink-secondary);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.question-badge {
  font-size: 0.7rem;
  font-weight: 800;
  padding: 3px 8px;
  border-radius: 4px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.question-badge.mc {
  background-color: var(--primary-bg);
  color: var(--primary);
}

.question-badge.rw {
  background-color: var(--warning-bg);
  color: var(--warning);
}

.question-text {
  font-size: 1.05rem;
  font-weight: 700;
  line-height: 1.5;
  color: var(--ink);
  margin-bottom: 20px;
}

.question-image-box {
  text-align: center;
  margin: 12px 0 20px;
}

.question-image-box img {
  max-width: 100%;
  max-height: 240px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
  background-color: #fff;
  padding: 4px;
}

/* Choices styling */
.choices-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.choice-option {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 14px 18px;
  background-color: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  cursor: pointer;
  transition: var(--transition);
  box-shadow: var(--shadow-sm);
}

.choice-option:hover {
  border-color: var(--primary);
  background-color: var(--surface-hover);
}

.choice-letter {
  width: 26px;
  height: 26px;
  background-color: var(--border);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.75rem;
  font-weight: 800;
  color: var(--ink-secondary);
  flex-shrink: 0;
}

.choice-text {
  font-size: 0.9rem;
  color: var(--ink);
  line-height: 1.4;
}

.choice-option.selected {
  border-color: var(--primary);
  background-color: var(--primary-bg);
}

.choice-option.selected .choice-letter {
  background-color: var(--primary);
  color: #fff;
}

.choice-option.correct {
  border-color: var(--success);
  background-color: var(--success-bg);
  animation: popSuccess 0.25s ease-out;
}

.choice-option.correct .choice-letter {
  background-color: var(--success);
  color: #fff;
}

.choice-option.incorrect {
  border-color: var(--danger);
  background-color: var(--danger-bg);
  animation: shakeError 0.3s ease-in-out;
}

.choice-option.incorrect .choice-letter {
  background-color: var(--danger);
  color: #fff;
}

.choice-option.disabled {
  pointer-events: none;
  opacity: 0.8;
}

/* True/False container grid - split two columns on wider views */
.tf-container {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 12px;
}

@media (max-width: 480px) {
  .tf-container {
    grid-template-columns: 1fr;
  }
}

.tf-option {
  flex-direction: row;
  justify-content: flex-start;
  padding: 16px;
}

/* Explanation Panel */
.explanation-card {
  margin-top: 18px;
  padding: 16px 20px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
  background-color: var(--surface-hover);
  position: relative;
  overflow: hidden;
}

.explanation-title {
  font-size: 0.82rem;
  font-weight: 800;
  text-transform: uppercase;
  color: var(--success);
  margin-bottom: 6px;
}

.explanation-text {
  font-size: 0.85rem;
  color: var(--ink-secondary);
}

/* Gated logic styling */
.explanation-locked {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 20px;
  background-color: var(--surface-hover);
  border-radius: var(--radius-sm);
  border: 1px dashed var(--border);
  margin-top: 18px;
}

.explanation-locked-blur {
  filter: blur(4px);
  opacity: 0.3;
  user-select: none;
  pointer-events: none;
  font-size: 0.85rem;
}

.explanation-unlock-cta {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  z-index: 10;
  background: var(--surface);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-lg);
  border-radius: var(--radius-sm);
  padding: 12px 18px;
  text-align: center;
  width: 85%;
}

.explanation-unlock-cta p {
  font-size: 0.78rem;
  font-weight: 700;
  color: var(--ink-secondary);
  margin-bottom: 8px;
}

/* Nav rows buttons */
.button-row {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  margin-top: 20px;
}

/* Styled application button */
.app-btn {
  padding: 12px 24px;
  border: 1px solid var(--border);
  background-color: var(--surface);
  color: var(--ink-secondary);
  font-family: inherit;
  font-size: 0.9rem;
  font-weight: 700;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: var(--transition);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  box-shadow: var(--shadow-sm);
}

.app-btn:hover {
  background-color: var(--surface-hover);
  color: var(--ink);
}

.app-btn.primary {
  background-color: var(--primary);
  border-color: var(--primary);
  color: #fff;
}

.app-btn.primary:hover {
  background-color: var(--primary-hover);
  border-color: var(--primary-hover);
}

.app-btn.success {
  background-color: var(--success);
  border-color: var(--success);
  color: #fff;
}

.app-btn.success:hover {
  background-color: var(--success-hover);
  border-color: var(--success-hover);
}

.app-btn:disabled {
  opacity: 0.4;
  pointer-events: none;
  box-shadow: none;
}

/* Test results detailed dashboard page */
.results-card {
  text-align: center;
  padding: 40px 24px;
}

.results-status {
  font-family: 'Outfit', var(--font-sans);
  font-size: 1.8rem;
  font-weight: 800;
  margin-bottom: 6px;
}

.results-status.pass { color: var(--success); }
.results-status.fail { color: var(--danger); }

.results-score-circle {
  width: 130px;
  height: 130px;
  border-radius: 50%;
  border: 8px solid var(--border);
  display: inline-flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  margin: 16px 0;
}

.results-score-circle.pass { border-color: var(--success-border); }
.results-score-circle.fail { border-color: var(--danger-border); }

.results-score-num {
  font-family: 'Outfit', var(--font-sans);
  font-size: 2.4rem;
  font-weight: 800;
  color: var(--ink);
  line-height: 1;
}

.results-score-lbl {
  font-size: 0.72rem;
  text-transform: uppercase;
  color: var(--ink-secondary);
  font-weight: 700;
  letter-spacing: 0.05em;
  margin-top: 2px;
}

.results-breakdown-row {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1px;
  background-color: var(--border);
  border-radius: var(--radius-sm);
  overflow: hidden;
  margin: 20px 0;
  border: 1px solid var(--border);
}

.results-cell {
  background-color: var(--surface);
  padding: 16px 12px;
}

.results-cell-val {
  font-size: 1.3rem;
  font-weight: 800;
}

.results-cell.correct { color: var(--success); }
.results-cell.incorrect { color: var(--danger); }
.results-cell.time { color: var(--ink); }

.results-cell-lbl {
  font-size: 0.68rem;
  color: var(--ink-secondary);
  text-transform: uppercase;
  margin-top: 4px;
}

/* Paywall overlay modal design */
.paywall-modal-overlay {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: rgba(15, 23, 42, 0.75);
  backdrop-filter: blur(5px);
  -webkit-backdrop-filter: blur(5px);
  display: flex;
  align-items: flex-end; /* Slides up from bottom */
  justify-content: center;
  z-index: 1000;
}

.paywall-modal-content {
  background-color: var(--surface);
  border-top-left-radius: 28px;
  border-top-right-radius: 28px;
  width: 100%;
  max-height: 85vh;
  overflow-y: auto;
  padding: 28px 24px;
  box-shadow: 0 -10px 30px rgba(0, 0, 0, 0.25);
  position: relative;
  animation: slideUpModal 0.25s cubic-bezier(0.16, 1, 0.3, 1);
}

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

.paywall-close-btn {
  position: absolute;
  top: 16px;
  right: 16px;
  background: var(--surface-hover);
  border: none;
  color: var(--ink-secondary);
  font-size: 1.3rem;
  cursor: pointer;
  width: 32px;
  height: 32px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: var(--transition);
}

.paywall-close-btn:hover {
  background-color: var(--surface-active);
  color: var(--ink);
}

.paywall-header {
  text-align: center;
  margin-bottom: 24px;
}

.paywall-header h2 {
  font-family: 'Outfit', var(--font-sans);
  font-size: 1.5rem;
  font-weight: 800;
  color: var(--ink);
}

.paywall-header p {
  font-size: 0.88rem;
  color: var(--ink-secondary);
}

/* Pricing selectors card grid (3 cards side-by-side) */
.pricing-options {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
  margin-bottom: 20px;
}

@media (max-width: 480px) {
  .pricing-options {
    grid-template-columns: 1fr;
    gap: 8px;
  }
}

.pricing-card {
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 16px 8px;
  text-align: center;
  cursor: pointer;
  transition: var(--transition);
  position: relative;
  background-color: var(--surface);
}

.pricing-card.selected {
  border-color: var(--primary);
  background-color: var(--primary-bg);
}

.pricing-card.popular {
  border-color: var(--warning);
}

.popular-badge {
  position: absolute;
  top: -10px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--warning);
  color: #fff;
  font-size: 0.58rem;
  font-weight: 800;
  padding: 2px 8px;
  border-radius: 9999px;
  text-transform: uppercase;
}

.plan-name {
  font-size: 0.7rem;
  font-weight: 800;
  text-transform: uppercase;
  color: var(--ink-secondary);
}

.pricing-card.selected .plan-name {
  color: var(--primary);
}

.plan-price {
  font-family: 'Outfit', var(--font-sans);
  font-size: 1.35rem;
  font-weight: 800;
  color: var(--ink);
}

.plan-period {
  font-size: 0.7rem;
  color: var(--ink-tertiary);
}

/* Detailed feature lists block */
.features-list {
  background-color: var(--surface-hover);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 16px 18px;
  margin-bottom: 20px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.feature-item {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--ink-secondary);
}

.feature-check-icon {
  color: var(--success);
  font-weight: 800;
}

/* Checkout panel simulator */
.checkout-panel {
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 16px;
  background-color: var(--surface);
  margin-bottom: 20px;
}

.checkout-tabs {
  display: flex;
  border-bottom: 1px solid var(--border);
  margin-bottom: 16px;
}

.checkout-tab {
  flex: 1;
  padding: 8px;
  background: transparent;
  border: none;
  font-size: 0.78rem;
  font-weight: 800;
  color: var(--ink-tertiary);
  cursor: pointer;
  border-bottom: 2px solid transparent;
  text-align: center;
}

.checkout-tab.active {
  color: var(--primary);
  border-bottom-color: var(--primary);
}

.qr-code-container {
  display: flex;
  align-items: center;
  justify-content: center;
  background: #fff;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  width: 110px;
  height: 110px;
  margin: 0 auto 10px;
}

.qr-placeholder {
  width: 95px;
  height: 95px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-weight: 800;
  font-size: 0.7rem;
  border-radius: 4px;
  text-align: center;
  position: relative;
}

.qr-placeholder::after {
  content: 'SCAN CODE';
  position: absolute;
  bottom: 2px;
  font-size: 0.5rem;
  color: var(--warning);
}

/* Promo voucher block */
.promo-section {
  border-top: 1px solid var(--border);
  padding-top: 16px;
}

.promo-title {
  font-size: 0.8rem;
  font-weight: 800;
  color: var(--ink-secondary);
  margin-bottom: 8px;
}

.promo-form {
  display: flex;
  gap: 8px;
}

.promo-input {
  flex: 1;
  padding: 8px 12px;
  background-color: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--ink);
  font-family: inherit;
  font-size: 0.85rem;
  outline: none;
}

.promo-input:focus {
  border-color: var(--primary);
}

/* General modal overlay */
.modal-overlay {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: rgba(15, 23, 42, 0.75);
  backdrop-filter: blur(4px);
  -webkit-backdrop-filter: blur(4px);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1000;
  padding: 24px;
}

.modal-content {
  background-color: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  width: 100%;
  max-width: 520px;
  max-height: 80vh;
  overflow-y: auto;
  padding: 24px;
  box-shadow: var(--shadow-lg);
  position: relative;
}

/* Demerit points navigation tabs */
.points-nav {
  display: flex;
  gap: 4px;
  margin-bottom: 16px;
  background-color: var(--surface-hover);
  padding: 4px;
  border-radius: var(--radius-sm);
}

.point-tab {
  flex: 1;
  padding: 8px 4px;
  background: transparent;
  border: none;
  font-size: 0.75rem;
  font-weight: 800;
  color: var(--ink-tertiary);
  cursor: pointer;
  border-radius: calc(var(--radius-sm) - 4px);
  text-align: center;
  transition: var(--transition);
}

.point-tab.active {
  background-color: var(--surface);
  color: var(--primary);
  box-shadow: var(--shadow-sm);
}

.violations-list {
  display: flex;
  flex-direction: column;
  gap: 8px;
  max-height: 42vh;
  overflow-y: auto;
}

.violation-card {
  padding: 10px 14px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
  font-size: 0.82rem;
  background-color: var(--surface-hover);
  line-height: 1.4;
}

/* Promo banner on dashboard */
.promo-banner {
  background: linear-gradient(135deg, var(--primary-bg) 0%, rgba(59, 130, 246, 0.04) 100%);
  border: 1px solid var(--primary);
  border-radius: var(--radius);
  padding: 16px 20px;
  margin-bottom: 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.promo-banner-text h3 {
  font-size: 0.95rem;
  font-weight: 800;
  color: var(--primary);
}

.promo-banner-text p {
  font-size: 0.8rem;
  color: var(--ink-secondary);
}

/* Detailed metrics layout on dashboard */
.performance-details {
  border-top: 1px solid var(--border);
  padding-top: 18px;
}

.performance-details h4 {
  font-size: 0.85rem;
  font-weight: 800;
  margin-bottom: 12px;
}

.topic-mastery-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.topic-mastery-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  font-size: 0.82rem;
}

.topic-mastery-name {
  flex: 3;
  font-weight: 600;
  color: var(--ink-secondary);
}

.topic-mastery-bar-bg {
  flex: 4;
  height: 6px;
  background-color: var(--border);
  border-radius: 999px;
  overflow: hidden;
}

.topic-mastery-bar-fill {
  height: 100%;
  background-color: var(--primary);
}

.topic-mastery-pct {
  font-weight: 800;
  color: var(--ink);
  min-width: 36px;
  text-align: right;
}

.locked-metrics-overlay {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 24px 16px;
  background: var(--surface-hover);
  border: 1px dashed var(--border);
  border-radius: var(--radius-sm);
  text-align: center;
}

.locked-metrics-overlay p {
  font-size: 0.82rem;
  color: var(--ink-secondary);
  margin-bottom: 12px;
}

/* Animations */
@keyframes shakeError {
  0%, 100% { transform: translateX(0); }
  20%, 60% { transform: translateX(-4px); }
  40%, 80% { transform: translateX(4px); }
}

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

/* Answer Feedback Box */
.answer-feedback {
  margin-top: 16px;
  padding: 12px 14px;
  border-radius: var(--radius-sm);
  font-size: 0.88rem;
  font-weight: 600;
  line-height: 1.5;
}
.answer-feedback.correct {
  background: var(--success-bg);
  border: 1px solid #b5dbc0;
  color: var(--success);
}
.answer-feedback.incorrect {
  background: var(--danger-bg);
  border: 1px solid #e8b0b0;
  color: var(--danger);
}
.answer-feedback .correct-answer {
  font-weight: 700;
  margin-top: 4px;
  font-size: 0.85rem;
}