/* ========================================
   DESIGN TOKENS - MODERN MINIMAL THEME
   ======================================== */

:root {
  /* Primary Colors - Clean Slate */
  --color-primary: #3b82f6;
  --color-primary-light: #60a5fa;
  --color-primary-lighter: #dbeafe;
  --color-primary-dark: #1e40af;

  /* Neutral Colors - Modern Gray */
  --color-neutral-50: #f9fafb;
  --color-neutral-100: #f3f4f6;
  --color-neutral-200: #e5e7eb;
  --color-neutral-300: #d1d5db;
  --color-neutral-400: #9ca3af;
  --color-neutral-600: #4b5563;
  --color-neutral-700: #374151;
  --color-neutral-800: #1f2937;
  --color-neutral-900: #111827;

  /* Semantic Colors */
  --color-success: #10b981;
  --color-success-light: #d1fae5;
  --color-warning: #f59e0b;
  --color-warning-light: #fef3c7;
  --color-danger: #ef4444;
  --color-danger-light: #fee2e2;

  /* Background & Text */
  --bg-primary: #ffffff;
  --bg-secondary: #f9fafb;
  --bg-tertiary: #f3f4f6;
  --text-primary: #111827;
  --text-secondary: #4b5563;
  --text-tertiary: #6b7280;
  --text-inverse: #ffffff;
  --border-color: #e5e7eb;

  /* Typography */
  --font-family: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  --font-size-xs: 0.75rem;
  --font-size-sm: 0.875rem;
  --font-size-base: 1rem;
  --font-size-lg: 1.125rem;
  --font-size-xl: 1.25rem;
  --font-size-2xl: 1.5rem;
  --font-size-3xl: 1.875rem;

  /* Spacing */
  --spacing-1: 0.25rem;
  --spacing-2: 0.5rem;
  --spacing-3: 0.75rem;
  --spacing-4: 1rem;
  --spacing-5: 1.25rem;
  --spacing-6: 1.5rem;
  --spacing-8: 2rem;
  --spacing-10: 2.5rem;
  --spacing-12: 3rem;

  /* Shadows */
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);

  /* Radius */
  --radius-sm: 6px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;

  /* Transitions */
  --transition-fast: 120ms ease-in-out;
  --transition-base: 180ms ease-in-out;
}

/* ========================================
   GLOBAL STYLES
   ======================================== */

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  padding: 0;
  font-family: var(--font-family);
  background: var(--bg-secondary);
  color: var(--text-primary);
}

body {
  font-size: var(--font-size-base);
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
}

h1,
h2,
h3,
h4,
h5,
h6 {
  margin: 0;
  font-weight: 600;
  line-height: 1.3;
}

h1 {
  font-size: var(--font-size-3xl);
}

h2 {
  font-size: var(--font-size-2xl);
}

h3 {
  font-size: var(--font-size-xl);
}

h4 {
  font-size: var(--font-size-lg);
}

h5 {
  font-size: var(--font-size-base);
  font-weight: 600;
}

p {
  margin: 0 0 var(--spacing-4) 0;
}

/* ========================================
   APP WRAPPER & LAYOUT
   ======================================== */

.app-wrapper {
  max-width: 1200px;
  margin: 0 auto;
  background: var(--bg-secondary);
  min-height: 100vh;
  width: 100%;
  overflow-x: hidden;
  display: flex;
  flex-direction: column;
}

/* ========================================
   PANEL STYLES (FULL-SCREEN MODALS)
   ======================================== */

.panel {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: var(--bg-primary);
  z-index: 1000;
  overflow-y: auto;
  overflow-x: hidden;
  -webkit-overflow-scrolling: touch;
  animation: slideUp 0.3s ease;
  display: flex;
  flex-direction: column;
}

@keyframes slideUp {
  from {
    transform: translateY(100%);
    opacity: 0;
  }

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

.panel-header {
  position: sticky;
  top: 0;
  background: var(--bg-primary);
  border-bottom: 1px solid var(--border-color);
  padding: var(--spacing-6);
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: var(--spacing-6);
  backdrop-filter: blur(8px);
  background: rgba(255, 255, 255, 0.95);
  z-index: 10;
  flex-wrap: wrap;
  flex-shrink: 0;
  box-sizing: border-box;
  width: 100%;
  padding-top: max(var(--spacing-6), env(safe-area-inset-top, var(--spacing-6)));
}

.panel-header h2 {
  font-size: var(--font-size-2xl);
  margin: 0;
  flex: 1;
}

.btn-close-panel {
  background: transparent;
  border: none;
  font-size: var(--font-size-2xl);
  cursor: pointer;
  color: var(--text-secondary);
  padding: 0;
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-md);
  transition: all var(--transition-fast);
  flex-shrink: 0;
}

.btn-close-panel:hover {
  background: var(--bg-tertiary);
  color: var(--text-primary);
}

/* ========================================
   PANEL HEADER IMPROVEMENTS
   ======================================== */

.btn-back {
  background: transparent;
  border: none;
  color: var(--color-primary);
  font-size: var(--font-size-base);
  font-weight: 600;
  cursor: pointer;
  padding: var(--spacing-2) var(--spacing-3);
  border-radius: var(--radius-md);
  transition: all var(--transition-fast);
  display: flex;
  align-items: center;
  gap: var(--spacing-1);
}

.btn-back:hover {
  background: var(--bg-tertiary);
  color: var(--color-primary-dark);
}

.panel-body {
  padding: var(--spacing-6);
  max-width: 900px;
  margin: 0 auto;
  flex: 1;
  overflow-y: auto;
  -webkit-overflow-scrolling: touch;
  width: 100%;
  box-sizing: border-box;
}

/* ========================================
   HOME VIEW
   ======================================== */

.home-view {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-12);
  padding: var(--spacing-8) var(--spacing-6);
  min-height: 100vh;
  width: 100%;
  box-sizing: border-box;
  padding-bottom: max(var(--spacing-8), env(safe-area-inset-bottom, var(--spacing-8)));
}

@media (min-width: 768px) {
  .home-view {
    padding: var(--spacing-12) var(--spacing-8);
  }
}

.home-header {
  text-align: center;
  padding: var(--spacing-10) 0;
}

.home-header h1 {
  font-size: clamp(2.5rem, 8vw, 3.5rem);
  color: var(--color-primary);
  margin-bottom: var(--spacing-2);
  font-weight: 700;
}

.subtitle {
  font-size: var(--font-size-lg);
  color: var(--text-secondary);
  margin: 0;
}

.home-actions {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--spacing-4);
  margin-bottom: var(--spacing-8);
}

@media (min-width: 640px) {
  .home-actions {
    grid-template-columns: 1fr 1fr;
  }
}

.action-button {
  display: flex;
  align-items: center;
  gap: var(--spacing-4);
  padding: var(--spacing-6);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  background: var(--bg-primary);
  cursor: pointer;
  transition: all var(--transition-base);
  text-align: left;
  font-size: inherit;
  font-family: inherit;
}

.action-button:hover {
  border-color: var(--color-primary);
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

.action-button .icon {
  font-size: 1.75rem;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 50px;
  height: 50px;
  background: var(--bg-tertiary);
  border-radius: var(--radius-md);
}

.button-title {
  font-weight: 600;
  color: var(--text-primary);
  font-size: var(--font-size-base);
}

.button-subtitle {
  font-size: var(--font-size-sm);
  color: var(--text-secondary);
  margin-top: var(--spacing-1);
}

/* ========================================
   TUTORIAL SECTION
   ======================================== */

.tutorial-section {
  background: var(--bg-primary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: var(--spacing-6);
}

.tutorial-header h4 {
  margin-bottom: var(--spacing-1);
  color: var(--text-primary);
}

.tutorial-subtitle {
  font-size: var(--font-size-sm);
  color: var(--text-secondary);
  margin: 0 0 var(--spacing-4) 0;
}

/* Quick Start Tutorial */
.tutorial-quick-start {
  border-left: 4px solid var(--color-primary);
}

.tutorial-steps {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-6);
}

.tutorial-step {
  display: flex;
  gap: var(--spacing-4);
  padding: var(--spacing-4);
  background: var(--bg-secondary);
  border-radius: var(--radius-md);
  border-left: 3px solid var(--color-primary-light);
}

.step-number {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  background: var(--color-primary);
  color: var(--text-inverse);
  border-radius: var(--radius-md);
  font-weight: 700;
  font-size: var(--font-size-lg);
  flex-shrink: 0;
}

.step-content {
  flex: 1;
}

.step-content h5 {
  margin-bottom: var(--spacing-2);
  color: var(--text-primary);
  font-weight: 600;
}

.step-description {
  margin-bottom: var(--spacing-3);
  color: var(--text-secondary);
  font-size: var(--font-size-sm);
}

.step-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: var(--spacing-2);
}

.step-list li {
  color: var(--text-primary);
  font-size: var(--font-size-sm);
  padding-left: var(--spacing-3);
  position: relative;
}

.step-list li::before {
  content: "→";
  position: absolute;
  left: 0;
  color: var(--color-primary);
  font-weight: bold;
}

/* Detailed Tutorial */
.tutorial-detailed {
  border-left: 4px solid var(--color-success);
}

.tutorial-features {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: var(--spacing-4);
}

.feature-card {
  display: flex;
  gap: var(--spacing-3);
  padding: var(--spacing-4);
  background: var(--bg-secondary);
  border-radius: var(--radius-md);
  border: 1px solid var(--border-color);
  transition: all var(--transition-fast);
}

.feature-card:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-sm);
  border-color: var(--color-success);
}

.feature-icon {
  font-size: 1.75rem;
  display: flex;
  align-items: flex-start;
  flex-shrink: 0;
}

.feature-content {
  flex: 1;
}

.feature-content h6 {
  margin: 0 0 var(--spacing-1) 0;
  font-weight: 600;
  color: var(--text-primary);
  font-size: var(--font-size-sm);
}

.feature-content p {
  margin: 0;
  font-size: var(--font-size-xs);
  color: var(--text-secondary);
  line-height: 1.5;
}

/* Tips Section */
.tutorial-tips {
  border-left: 4px solid var(--color-warning);
  background: linear-gradient(135deg, var(--bg-primary) 0%, var(--bg-secondary) 100%);
}

.tips-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: var(--spacing-3);
}

.tips-list li {
  padding: var(--spacing-3) var(--spacing-4);
  background: var(--bg-primary);
  border-radius: var(--radius-md);
  border-left: 3px solid var(--color-warning);
  color: var(--text-primary);
  font-size: var(--font-size-sm);
  line-height: 1.6;
}

/* ========================================
   GENERATOR PROMPT - SIMPLIFIED
   ======================================== */

.generator-prompt-container {
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: var(--spacing-4);
  display: flex;
  flex-direction: column;
  gap: var(--spacing-3);
}

.generator-prompt-container .prompt-text {
  margin: 0;
  font-size: 0.8rem;
  color: var(--text-primary);
  line-height: 1.6;
  word-wrap: break-word;
  max-height: 300px;
  overflow-y: auto;
  padding: var(--spacing-3);
  background: var(--bg-primary);
  border-radius: var(--radius-md);
  border: 1px solid var(--border-color);
}

.btn-copy {
  align-self: flex-start;
  display: inline-flex;
  align-items: center;
  gap: var(--spacing-2);
}

.generator-prompt {
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: var(--spacing-4);
  overflow-x: auto;
}

.prompt-text {
  margin: 0;
  font-size: var(--font-size-xs);
  color: var(--text-primary);
  line-height: 1.6;
  word-wrap: break-word;
}

/* ========================================
   BUTTONS
   ======================================== */

.btn {
  padding: var(--spacing-3) var(--spacing-5);
  border: 1px solid transparent;
  border-radius: var(--radius-md);
  font-size: var(--font-size-base);
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition-fast);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-2);
  min-height: 48px;
  min-width: 48px;
  font-family: inherit;
  -webkit-tap-highlight-color: transparent;
  user-select: none;
  -webkit-user-select: none;
}

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

.btn:disabled {
  opacity: 0.6;
  cursor: not-allowed;
  pointer-events: none;
}

.btn-primary {
  background: var(--color-primary);
  color: var(--text-inverse);
  border-color: var(--color-primary);
}

.btn-primary:hover:not(:disabled) {
  background: var(--color-primary-dark);
  border-color: var(--color-primary-dark);
  transform: scale(1.02);
}

.btn-primary:active:not(:disabled) {
  transform: scale(0.98);
}

.btn-secondary {
  background: transparent;
  color: var(--color-primary);
  border: 1px solid var(--border-color);
}

.btn-secondary:hover:not(:disabled) {
  background: var(--bg-tertiary);
  border-color: var(--color-primary);
}

.btn-sm {
  padding: var(--spacing-2) var(--spacing-4);
  font-size: var(--font-size-sm);
  min-height: 36px;
}

.btn-link {
  background: transparent;
  color: var(--color-primary);
  border: none;
  padding: var(--spacing-2) 0;
  text-decoration: none;
}

.btn-link:hover {
  text-decoration: underline;
}

/* ========================================
   QUESTION NAVIGATOR
   ======================================== */

.question-navigator {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(40px, 1fr));
  gap: var(--spacing-2);
  padding: var(--spacing-4);
  background: var(--bg-secondary);
  border-radius: var(--radius-lg);
}

.nav-tile {
  aspect-ratio: 1;
  border: 2px solid var(--border-color);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  font-weight: 600;
  font-size: var(--font-size-sm);
  transition: all var(--transition-fast);
  background: var(--bg-primary);
  color: var(--text-primary);
  user-select: none;
  min-height: 40px;
}

.nav-tile:hover {
  border-color: var(--color-primary);
  transform: scale(1.1);
  box-shadow: var(--shadow-sm);
}

.nav-tile.current {
  border-color: var(--color-primary);
  border-width: 3px;
  background: var(--color-primary-lighter);
  color: var(--color-primary-dark);
}

.nav-tile.answered {
  background: var(--color-success-light);
  border-color: var(--color-success);
  color: var(--color-success);
}

.nav-tile.marked {
  background: var(--color-warning-light);
  border-color: var(--color-warning);
  color: var(--color-warning);
}

/* ========================================
   EXAM TIMER
   ======================================== */

.exam-info-bar {
  padding: var(--spacing-3);
  margin-top: var(--spacing-3);
}

.timer-container {
  background: var(--bg-secondary);
  border-radius: var(--radius-md);
  padding: var(--spacing-3);
  transition: all var(--transition-base);
}

.timer-container.timer-ok {
  border-left: 4px solid var(--color-success);
}

.timer-container.timer-warning {
  border-left: 4px solid var(--color-warning);
  background: #fef3c7;
}

.timer-container.timer-critical {
  border-left: 4px solid var(--color-danger);
  background: #fee2e2;
  animation: pulse-critical 1s ease-in-out infinite;
}

@keyframes pulse-critical {

  0%,
  100% {
    opacity: 1;
  }

  50% {
    opacity: 0.8;
  }
}

.timer-text {
  font-size: var(--font-size-sm);
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: var(--spacing-2);
}

.timer-value {
  font-size: var(--font-size-lg);
  color: var(--color-primary);
  font-weight: 700;
}

.timer-container.timer-warning .timer-value {
  color: var(--color-warning);
}

.timer-container.timer-critical .timer-value {
  color: var(--color-danger);
}

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

.timer-bar-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--color-success), var(--color-primary));
  border-radius: var(--radius-full);
  transition: width 0.5s ease-out;
}

.timer-container.timer-warning .timer-bar-fill {
  background: linear-gradient(90deg, var(--color-warning), var(--color-warning));
}

.timer-container.timer-critical .timer-bar-fill {
  background: linear-gradient(90deg, var(--color-danger), var(--color-danger));
}

/* ========================================
   QUESTION CARD
   ======================================== */

.question-card {
  background: var(--bg-primary);
  border-radius: var(--radius-lg);
  padding: var(--spacing-8);
  box-shadow: var(--shadow-sm);
  width: 100%;
}

@media (max-width: 768px) {
  .question-card {
    padding: var(--spacing-6);
  }
}

.question-number {
  font-size: var(--font-size-sm);
  color: var(--text-tertiary);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.question-text {
  font-size: clamp(1rem, 4vw, 1.5rem);
  font-weight: 600;
  line-height: 1.6;
  color: var(--text-primary);
  margin-bottom: var(--spacing-6);
}

/* ========================================
   OPTIONS
   ======================================== */

.options-list {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-3);
  list-style: none;
  padding: 0;
  margin: 0 0 var(--spacing-6) 0;
}

.option-item {
  display: flex;
  align-items: flex-start;
  padding: var(--spacing-4) var(--spacing-5);
  border: 2px solid var(--border-color);
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all var(--transition-fast);
  background: var(--bg-primary);
  position: relative;
  gap: var(--spacing-3);
  min-height: 60px;
  -webkit-tap-highlight-color: transparent;
  -webkit-user-select: none;
  user-select: none;
}

.option-item:hover {
  border-color: var(--color-primary-light);
  background: var(--color-primary-lighter);
  transform: translateY(-2px);
}

.option-item.selected {
  border-color: var(--color-primary);
  background: var(--color-primary-lighter);
  box-shadow: var(--shadow-md);
}

.option-item.selected::after {
  content: "✓";
  position: absolute;
  right: var(--spacing-4);
  top: 50%;
  transform: translateY(-50%);
  color: var(--color-primary);
  font-weight: 700;
  font-size: var(--font-size-lg);
}

.option-item input[type="radio"] {
  width: 20px;
  height: 20px;
  cursor: pointer;
  accent-color: var(--color-primary);
  flex-shrink: 0;
  margin-top: 2px;
}

.option-item span {
  flex: 1;
  color: var(--text-primary);
  line-height: 1.6;
}

/* ========================================
   QUESTION CONTROLS
   ======================================== */

.question-controls {
  display: flex;
  gap: var(--spacing-3);
  flex-wrap: wrap;
  margin-top: var(--spacing-6);
  padding-top: var(--spacing-6);
  border-top: 1px solid var(--border-color);
}

/* ========================================
   FORMS
   ======================================== */

.form-group {
  display: flex;
  flex-direction: column;
}

.form-label {
  font-size: var(--font-size-sm);
  font-weight: 600;
  color: var(--text-secondary);
  margin-bottom: var(--spacing-2);
  display: block;
}

.form-control {
  padding: var(--spacing-3) var(--spacing-4);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  background: var(--bg-primary);
  color: var(--text-primary);
  font-family: inherit;
  font-size: 16px;
  transition: all var(--transition-fast);
  width: 100%;
  min-height: 48px;
  box-sizing: border-box;
}

.form-control:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px var(--color-primary-lighter);
}

.form-control:disabled,
.form-control[readonly] {
  background: var(--bg-tertiary);
  color: var(--text-tertiary);
  cursor: not-allowed;
}

textarea.form-control {
  resize: vertical;
  min-height: 120px;
}

.form-check {
  display: flex;
  align-items: center;
  gap: var(--spacing-2);
}

.form-check-input {
  width: 20px;
  height: 20px;
  cursor: pointer;
  accent-color: var(--color-primary);
}

.form-check-label {
  cursor: pointer;
  color: var(--text-primary);
}

/* ========================================
   LIST GROUPS
   ======================================== */

.list-group {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-2);
  list-style: none;
  padding: 0;
  margin: 0;
}

.list-group-item {
  padding: var(--spacing-4);
  background: var(--bg-primary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.list-group-item:hover {
  border-color: var(--color-primary);
  background: var(--bg-tertiary);
  transform: translateX(4px);
}

/* ========================================
   RESULTS
   ======================================== */

.results-card {
  background: var(--bg-primary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: var(--spacing-6);
  text-align: center;
}

.results-card h4 {
  color: var(--color-primary);
  margin-bottom: var(--spacing-2);
}

.topic-summary-item {
  padding: var(--spacing-4) var(--spacing-5);
  background: var(--bg-primary);
  border-left: 4px solid var(--border-color);
  border-radius: var(--radius-md);
  border: 1px solid var(--border-color);
  border-left: 4px solid var(--color-primary);
  transition: all var(--transition-fast);
  margin-bottom: var(--spacing-2);
}

.topic-summary-item:hover {
  box-shadow: var(--shadow-sm);
}

.topic-summary-item.strong {
  border-left-color: var(--color-success);
}

.topic-summary-item.average {
  border-left-color: var(--color-warning);
}

.topic-summary-item.weak {
  border-left-color: var(--color-danger);
}

/* ========================================
   ALERTS
   ======================================== */

.alert {
  padding: var(--spacing-4) var(--spacing-5);
  border-radius: var(--radius-md);
  border-left: 4px solid;
  margin-bottom: var(--spacing-4);
}

.alert-danger {
  background: var(--color-danger-light);
  border-left-color: var(--color-danger);
  color: var(--text-primary);
}

.alert-success {
  background: var(--color-success-light);
  border-left-color: var(--color-success);
  color: var(--text-primary);
}

/* ========================================
   DETAILED REVIEW - IMPROVED
   ======================================== */

.detailed-results {
  background: var(--bg-primary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 0;
  overflow: hidden;
}

.question-review {
  border-bottom: 1px solid var(--border-color);
  transition: all var(--transition-fast);
}

.question-review:last-child {
  border-bottom: none;
}

.review-header {
  padding: var(--spacing-4);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: var(--bg-primary);
  transition: all var(--transition-fast);
  user-select: none;
}

.review-header:hover {
  background: var(--bg-secondary);
}

.review-header-left {
  display: flex;
  align-items: center;
  gap: var(--spacing-3);
  flex: 1;
  min-width: 0;
}

.review-status-badge {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  border-radius: var(--radius-md);
  font-weight: 600;
  font-size: var(--font-size-sm);
  flex-shrink: 0;
}

.review-status-badge.correct {
  background: var(--color-success-light);
  color: var(--color-success);
  border: 1px solid var(--color-success);
}

.review-status-badge.incorrect {
  background: var(--color-danger-light);
  color: var(--color-danger);
  border: 1px solid var(--color-danger);
}

.review-header-text {
  flex: 1;
  min-width: 0;
}

.review-question-text {
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: var(--spacing-1);
  line-height: 1.4;
  word-break: break-word;
}

.review-question-meta {
  font-size: var(--font-size-sm);
  color: var(--text-tertiary);
}

.review-toggle-icon {
  font-size: var(--font-size-lg);
  transition: transform var(--transition-fast);
  flex-shrink: 0;
}

.question-review.open .review-toggle-icon {
  transform: rotate(180deg);
}

.review-content {
  display: none;
  padding: var(--spacing-4);
  background: var(--bg-secondary);
  border-top: 1px solid var(--border-color);
}

.question-review.open .review-content {
  display: block;
}

.options-review {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-2);
  margin-bottom: var(--spacing-4);
}

.option-review {
  padding: var(--spacing-3) var(--spacing-4);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  background: var(--bg-primary);
  display: flex;
  align-items: flex-start;
  gap: var(--spacing-3);
  transition: all var(--transition-fast);
}

.option-review.correct {
  border-color: var(--color-success);
  background: var(--color-success-light);
}

.option-review.incorrect {
  border-color: var(--color-danger);
  background: var(--color-danger-light);
}

.option-review.user-selected {
  box-shadow: var(--shadow-sm);
}

.option-label {
  font-weight: 600;
  color: var(--text-primary);
  min-width: 2.5rem;
  flex-shrink: 0;
}

.option-text {
  flex: 1;
  color: var(--text-primary);
  line-height: 1.5;
}

.option-indicator {
  font-size: var(--font-size-sm);
  font-weight: 600;
  flex-shrink: 0;
}

.review-explanation {
  background: var(--bg-primary);
  border-left: 3px solid var(--color-primary);
  padding: var(--spacing-3) var(--spacing-4);
  border-radius: var(--radius-md);
  margin-top: var(--spacing-3);
}

.explanation-label {
  font-size: var(--font-size-sm);
  font-weight: 600;
  color: var(--text-secondary);
  margin-bottom: var(--spacing-1);
}

.explanation-text {
  color: var(--text-primary);
  line-height: 1.6;
}

/* ========================================
   RESPONSIVE DESIGN - MOBILE OPTIMIZED
   ======================================== */

/* Tablet screens (max-width: 768px) */
@media (max-width: 768px) {
  .home-header h1 {
    font-size: clamp(2rem, 7vw, 2.8rem);
  }

  .question-text {
    font-size: clamp(0.95rem, 3.5vw, 1.25rem);
  }

  .option-item input[type="radio"] {
    width: 18px;
    height: 18px;
  }
}

/* Small devices (max-width: 640px) */
@media (max-width: 640px) {
  :root {
    /* Adjust spacing for mobile */
    --spacing-8: 1.5rem;
    --spacing-10: 2rem;
    --spacing-12: 2.5rem;
  }

  .panel-header {
    padding: var(--spacing-4);
    flex-direction: column;
    align-items: flex-start;
    gap: var(--spacing-3);
  }

  .panel-header h2 {
    font-size: clamp(1.25rem, 6vw, 1.75rem);
    word-break: break-word;
  }

  .panel-body {
    padding: var(--spacing-4);
    max-width: 100%;
  }

  .question-card {
    padding: var(--spacing-4);
  }

  .question-number {
    font-size: var(--font-size-xs);
  }

  .question-text {
    font-size: clamp(0.95rem, 4vw, 1.25rem);
    margin-bottom: var(--spacing-4);
  }

  .home-actions {
    grid-template-columns: 1fr;
    gap: var(--spacing-3);
  }

  .action-button {
    padding: var(--spacing-4) var(--spacing-5);
    flex-direction: column;
    text-align: center;
    gap: var(--spacing-3);
  }

  .action-button .icon {
    width: 45px;
    height: 45px;
    font-size: 1.5rem;
  }

  .button-title {
    font-size: var(--font-size-sm);
  }

  .button-subtitle {
    font-size: var(--font-size-xs);
  }

  .question-controls {
    flex-direction: column;
    gap: var(--spacing-2);
  }

  .question-controls .btn {
    width: 100%;
  }

  .btn {
    min-height: 48px;
    min-width: 48px;
    padding: var(--spacing-3) var(--spacing-4);
  }

  .btn-sm {
    min-height: 44px;
    min-width: 44px;
    padding: var(--spacing-2) var(--spacing-3);
  }

  .tutorial-section {
    padding: var(--spacing-4);
  }

  .tutorial-steps {
    gap: var(--spacing-4);
  }

  .tutorial-step {
    flex-direction: column;
    gap: var(--spacing-3);
    padding: var(--spacing-3);
  }

  .step-number {
    width: 36px;
    height: 36px;
    font-size: var(--font-size-base);
  }

  .step-content h5 {
    font-size: var(--font-size-sm);
  }

  .step-description {
    font-size: var(--font-size-xs);
  }

  .step-list {
    gap: var(--spacing-1);
  }

  .step-list li {
    font-size: var(--font-size-xs);
    padding-left: var(--spacing-2);
  }

  .tutorial-features {
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--spacing-3);
  }

  .feature-card {
    padding: var(--spacing-3);
    gap: var(--spacing-2);
  }

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

  .tips-list {
    gap: var(--spacing-2);
  }

  .tips-list li {
    padding: var(--spacing-2) var(--spacing-3);
    font-size: var(--font-size-xs);
  }

  .generator-prompt-container {
    padding: var(--spacing-3);
    gap: var(--spacing-2);
  }

  .generator-prompt-container .prompt-text {
    font-size: 0.75rem;
    max-height: 200px;
    padding: var(--spacing-2);
  }

  .btn-copy {
    width: 100%;
    justify-content: center;
  }

  .options-list {
    gap: var(--spacing-2);
  }

  .option-item {
    padding: var(--spacing-3) var(--spacing-4);
    gap: var(--spacing-2);
    min-height: 56px;
  }

  .option-item input[type="radio"] {
    width: 20px;
    height: 20px;
    cursor: pointer;
  }

  .option-item span {
    font-size: var(--font-size-sm);
  }

  .form-control {
    padding: var(--spacing-3) var(--spacing-3);
    font-size: 16px;
    min-height: 48px;
  }

  textarea.form-control {
    min-height: 120px;
  }

  .list-group-item {
    padding: var(--spacing-3);
    font-size: var(--font-size-sm);
  }

  .review-header {
    padding: var(--spacing-3);
  }

  .review-header-left {
    gap: var(--spacing-2);
  }

  .review-status-badge {
    width: 28px;
    height: 28px;
    font-size: var(--font-size-xs);
  }

  .review-question-text {
    font-size: var(--font-size-sm);
  }

  .option-review {
    padding: var(--spacing-2) var(--spacing-3);
    gap: var(--spacing-2);
  }

  .option-label {
    min-width: 2rem;
    font-size: var(--font-size-sm);
  }

  .option-text {
    font-size: var(--font-size-sm);
  }

  .results-card {
    padding: var(--spacing-4);
  }

  .topic-summary-item {
    padding: var(--spacing-3) var(--spacing-4);
    font-size: var(--font-size-sm);
  }

  .question-navigator {
    gap: var(--spacing-1);
    padding: var(--spacing-3);
  }

  .nav-tile {
    min-height: 38px;
    font-size: var(--font-size-xs);
  }

  .home-header {
    padding: var(--spacing-6) 0;
  }

  .home-view {
    padding: var(--spacing-6) var(--spacing-4);
    gap: var(--spacing-8);
  }
}

/* Extra small devices (max-width: 480px) */
@media (max-width: 480px) {
  :root {
    --spacing-6: 1.25rem;
    --spacing-8: 1.5rem;
  }

  html,
  body {
    font-size: 15px;
  }

  .home-view {
    padding: var(--spacing-5) var(--spacing-3);
    gap: var(--spacing-6);
  }

  .home-header {
    padding: var(--spacing-5) 0;
  }

  .home-header h1 {
    font-size: 1.75rem;
    margin-bottom: var(--spacing-1);
  }

  .subtitle {
    font-size: var(--font-size-sm);
  }

  .panel-header {
    padding: var(--spacing-3);
    gap: var(--spacing-2);
  }

  .panel-header h2 {
    font-size: 1.25rem;
  }

  .btn-back {
    padding: var(--spacing-1) var(--spacing-2);
    font-size: var(--font-size-sm);
  }

  .btn-close-panel {
    width: 36px;
    height: 36px;
    font-size: 1.5rem;
  }

  .panel-body {
    padding: var(--spacing-3);
  }

  .question-card {
    padding: var(--spacing-3);
  }

  .question-number {
    font-size: var(--font-size-xs);
  }

  .question-text {
    font-size: 0.95rem;
    margin-bottom: var(--spacing-3);
  }

  .action-button {
    padding: var(--spacing-3) var(--spacing-4);
    gap: var(--spacing-2);
  }

  .action-button .icon {
    width: 40px;
    height: 40px;
    font-size: 1.25rem;
  }

  .button-title {
    font-size: var(--font-size-xs);
    font-weight: 600;
  }

  .button-subtitle {
    font-size: 0.7rem;
  }

  .btn {
    min-height: 44px;
    min-width: 44px;
    padding: var(--spacing-2) var(--spacing-3);
    font-size: var(--font-size-sm);
  }

  .btn-sm {
    min-height: 40px;
    min-width: 40px;
    padding: var(--spacing-2) var(--spacing-3);
    font-size: 0.8rem;
  }

  .form-label {
    font-size: var(--font-size-xs);
    margin-bottom: var(--spacing-1);
  }

  .form-control {
    padding: var(--spacing-2) var(--spacing-3);
    font-size: 16px;
    border-radius: var(--radius-sm);
    min-height: 44px;
  }

  textarea.form-control {
    min-height: 100px;
  }

  .form-group {
    margin-bottom: var(--spacing-3);
  }

  .tutorial-section {
    padding: var(--spacing-3);
  }

  .tutorial-header h4 {
    font-size: var(--font-size-base);
    margin-bottom: var(--spacing-2);
  }

  .tutorial-subtitle {
    font-size: var(--font-size-xs);
    margin-bottom: var(--spacing-3);
  }

  .generator-prompt-container {
    padding: var(--spacing-2);
    gap: var(--spacing-2);
  }

  .generator-prompt-container .prompt-text {
    font-size: 0.7rem;
    max-height: 150px;
    padding: var(--spacing-2);
    line-height: 1.4;
  }

  .btn-copy {
    width: 100%;
    padding: var(--spacing-2) var(--spacing-3);
    font-size: var(--font-size-sm);
  }

  .question-navigator {
    gap: 6px;
    padding: var(--spacing-2);
    grid-template-columns: repeat(auto-fill, minmax(32px, 1fr));
  }

  .nav-tile {
    min-height: 32px;
    font-size: 0.65rem;
    aspect-ratio: auto;
  }

  .option-item {
    padding: var(--spacing-3) var(--spacing-3);
    gap: var(--spacing-2);
    min-height: 54px;
  }

  .option-item input[type="radio"] {
    width: 18px;
    height: 18px;
    margin-top: 1px;
    cursor: pointer;
  }

  .option-item span {
    font-size: 0.9rem;
    line-height: 1.4;
  }

  .question-controls {
    flex-direction: column;
    gap: var(--spacing-2);
    margin-top: var(--spacing-4);
    padding-top: var(--spacing-4);
  }

  .question-controls .btn {
    width: 100%;
  }

  .list-group {
    gap: var(--spacing-1);
  }

  .list-group-item {
    padding: var(--spacing-2) var(--spacing-3);
    font-size: var(--font-size-xs);
  }

  .results-card {
    padding: var(--spacing-3);
  }

  .results-card h4 {
    font-size: var(--font-size-lg);
    margin-bottom: var(--spacing-2);
  }

  .topic-summary-item {
    padding: var(--spacing-2) var(--spacing-3);
    margin-bottom: var(--spacing-1);
    font-size: var(--font-size-xs);
  }

  .review-header {
    padding: var(--spacing-2) var(--spacing-3);
  }

  .review-status-badge {
    width: 24px;
    height: 24px;
    font-size: 0.65rem;
  }

  .review-question-text {
    font-size: var(--font-size-xs);
    line-height: 1.3;
  }

  .review-question-meta {
    font-size: 0.65rem;
  }

  .option-review {
    padding: var(--spacing-2);
    gap: var(--spacing-1);
  }

  .option-label {
    min-width: 1.75rem;
    font-size: var(--font-size-xs);
  }

  .option-text {
    font-size: var(--font-size-xs);
    line-height: 1.4;
  }

  .review-explanation {
    padding: var(--spacing-2) var(--spacing-3);
    margin-top: var(--spacing-2);
  }

  .explanation-label {
    font-size: 0.65rem;
  }

  .explanation-text {
    font-size: var(--font-size-xs);
    line-height: 1.4;
  }

  .alert {
    padding: var(--spacing-3) var(--spacing-3);
    font-size: var(--font-size-sm);
    margin-bottom: var(--spacing-3);
  }

  h1 {
    font-size: var(--font-size-2xl);
  }

  h2 {
    font-size: var(--font-size-xl);
  }

  h3 {
    font-size: var(--font-size-lg);
  }

  h4 {
    font-size: var(--font-size-base);
  }

  h5 {
    font-size: var(--font-size-base);
    margin-bottom: var(--spacing-2);
  }

  p {
    margin-bottom: var(--spacing-3);
  }
}

/* Ultra small devices (max-width: 360px) */
@media (max-width: 360px) {
  .home-header h1 {
    font-size: 1.5rem;
  }

  .question-navigator {
    grid-template-columns: repeat(auto-fill, minmax(28px, 1fr));
  }

  .nav-tile {
    min-height: 28px;
    font-size: 0.6rem;
  }

  .option-item {
    padding: var(--spacing-2);
    gap: var(--spacing-1);
  }

  .button-title {
    font-size: 0.75rem;
  }

  .button-subtitle {
    font-size: 0.65rem;
  }

  .generator-prompt-container .prompt-text {
    font-size: 0.65rem;
  }
}

/* Utility Classes */
.d-flex {
  display: flex;
}

.gap-2 {
  gap: var(--spacing-2);
}

.gap-3 {
  gap: var(--spacing-3);
}

.gap-4 {
  gap: var(--spacing-4);
}

.mb-2 {
  margin-bottom: var(--spacing-2);
}

.mb-3 {
  margin-bottom: var(--spacing-3);
}

.mb-4 {
  margin-bottom: var(--spacing-4);
}

.mt-2 {
  margin-top: var(--spacing-2);
}

.mt-3 {
  margin-top: var(--spacing-3);
}

.mt-4 {
  margin-top: var(--spacing-4);
}

.mt-5 {
  margin-top: var(--spacing-5);
}

/* ========================================
   ENHANCED MOBILE & RESPONSIVE ADJUSTMENTS
   ======================================== */

/* Prevent zoom on input focus on mobile */
@media (max-width: 640px) {

  input,
  textarea,
  select {
    font-size: 16px;
  }

  /* Better touch feedback on buttons and interactive elements */
  .btn:active:not(:disabled),
  .option-item:active,
  .list-group-item:active,
  .nav-tile:active {
    opacity: 0.85;
    transform: scale(0.98);
  }

  /* Smooth scrolling on mobile */
  html {
    scroll-behavior: smooth;
  }

  /* Prevent double tap zoom on buttons */
  .btn,
  .option-item,
  .nav-tile,
  .list-group-item {
    touch-action: manipulation;
  }

  /* Better spacing for stacked layout */
  .panel-header {
    gap: var(--spacing-3);
  }

  /* Ensure full screen panels are truly full */
  .panel {
    width: 100vw;
    max-width: 100%;
  }

  /* Better question card spacing on small screens */
  .question-card {
    border-radius: var(--radius-lg);
  }

  /* Improve readability on very small screens */
  body {
    line-height: 1.6;
  }

  .question-text {
    word-spacing: 0.1em;
  }

  .option-item span {
    word-spacing: 0.05em;
  }
}

/* Landscape mode adjustments */
@media (max-height: 600px) and (orientation: landscape) {
  .home-view {
    padding: var(--spacing-4) var(--spacing-6);
    gap: var(--spacing-6);
  }

  .panel-header {
    padding: var(--spacing-3);
  }

  .panel-body {
    padding: var(--spacing-4);
  }

  .question-card {
    padding: var(--spacing-4);
  }

  .question-text {
    margin-bottom: var(--spacing-3);
  }

  .options-list {
    gap: var(--spacing-2);
  }

  .question-navigator {
    padding: var(--spacing-2);
    gap: var(--spacing-1);
  }

  .nav-tile {
    min-height: 36px;
  }
}

/* High DPI / Retina displays */
@media (-webkit-min-device-pixel-ratio: 2),
(min-resolution: 192dpi) {

  .btn,
  .option-item,
  .nav-tile,
  .list-group-item {
    -webkit-font-smoothing: subpixel-antialiased;
  }
}

/* ========================================
   ANALYTICS STYLES
   ======================================== */

.analytics-overview {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
  padding: 2rem;
  border-radius: 12px;
  margin-bottom: 1.5rem;
  box-shadow: var(--shadow-lg);
}

.analytics-overview h3 {
  margin: 0 0 1rem 0;
  font-size: var(--font-size-2xl);
  font-weight: 700;
}

.analytics-stat-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
  gap: 1rem;
  margin-top: 1rem;
}

.analytics-stat {
  text-align: center;
  background: rgba(255, 255, 255, 0.1);
  padding: 1rem;
  border-radius: var(--radius-md);
  backdrop-filter: blur(10px);
}

.analytics-stat-value {
  font-size: 2rem;
  font-weight: 700;
  display: block;
  margin-bottom: 0.25rem;
}

.analytics-stat-label {
  font-size: 0.875rem;
  opacity: 0.9;
  display: block;
}

/* Weak Topics List */
.weak-topics-list {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.weak-topic-card {
  background: #fff3cd;
  border-left: 4px solid #ffc107;
  padding: 1rem;
  border-radius: 6px;
  transition: all var(--transition-fast);
}

.weak-topic-card:hover {
  box-shadow: var(--shadow-md);
  transform: translateX(4px);
}

.weak-topic-name {
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 0.25rem;
}

.weak-topic-meta {
  font-size: var(--font-size-sm);
  color: var(--text-secondary);
  margin-bottom: 0.5rem;
}

.weak-topic-accuracy {
  font-weight: 600;
  color: #dc3545;
}

/* Performance Analysis */
.performance-analysis {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.performance-item {
  background: var(--bg-primary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 1rem;
  transition: all var(--transition-fast);
}

.performance-item:hover {
  box-shadow: var(--shadow-sm);
  border-color: var(--color-primary);
}

.performance-item-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 0.5rem;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.performance-item-name {
  font-weight: 600;
  color: var(--text-primary);
  flex: 1;
}

.performance-item-stats {
  font-size: var(--font-size-sm);
  color: var(--text-secondary);
  display: flex;
  gap: 1rem;
  align-items: center;
}

.performance-accuracy {
  font-weight: 700;
  font-size: var(--font-size-base);
}

.performance-accuracy.weak {
  color: #dc3545;
}

.performance-accuracy.average {
  color: #ffc107;
}

.performance-accuracy.strong {
  color: #28a745;
}

/* Performance Bar */
.performance-bar {
  width: 100%;
  height: 8px;
  background: #e9ecef;
  border-radius: 4px;
  overflow: hidden;
  margin-top: 0.5rem;
}

.performance-bar-fill {
  height: 100%;
  transition: width 0.5s ease;
  border-radius: 4px;
}

.performance-bar-fill.weak {
  background: linear-gradient(90deg, #dc3545, #c82333);
}

.performance-bar-fill.average {
  background: linear-gradient(90deg, #ffc107, #e0a800);
}

.performance-bar-fill.strong {
  background: linear-gradient(90deg, #28a745, #218838);
}

/* Status Badge */
.status-badge {
  display: inline-block;
  padding: 0.25rem 0.75rem;
  border-radius: 12px;
  font-size: var(--font-size-xs);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.status-badge.weak {
  background: #fee2e2;
  color: #dc3545;
}

.status-badge.average {
  background: #fef3c7;
  color: #f59e0b;
}

.status-badge.strong {
  background: #d1fae5;
  color: #10b981;
}

/* Empty State */
.analytics-empty {
  text-align: center;
  padding: 3rem 1rem;
  color: var(--text-secondary);
}

.analytics-empty-icon {
  font-size: 4rem;
  margin-bottom: 1rem;
  opacity: 0.5;
}

.analytics-empty h4 {
  margin-bottom: 0.5rem;
  color: var(--text-primary);
}

.analytics-empty p {
  margin: 0;
  font-size: var(--font-size-sm);
}

/* Responsive adjustments */
@media (max-width: 640px) {
  .analytics-stat-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .performance-item-header {
    flex-direction: column;
    align-items: flex-start;
  }

  .performance-item-stats {
    width: 100%;
    justify-content: space-between;
  }
}

/* Reduced motion support for accessibility */
@media (prefers-reduced-motion: reduce) {

  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

/* Dark mode ready (future enhancement) */
@media (prefers-color-scheme: dark) {

  /* CSS variables will naturally adapt to dark mode */
  body {
    background: var(--bg-secondary);
    color: var(--text-primary);
  }
}

/* ========================================
   GALLERY STYLES - APPLE INSPIRED DESIGN
   ======================================== */

/* Gallery Panel Specific */
.gallery-panel-header {
  flex-shrink: 0;
}

.gallery-panel-body {
  padding-top: 0 !important;
}

/* Sticky Navigation Container */
.gallery-nav-container {
  position: sticky;
  top: 0;
  background: linear-gradient(to bottom, var(--bg-primary) 85%, transparent);
  z-index: 15;
  padding: var(--spacing-4) var(--spacing-6);
  margin: 0;
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
}

/* Search Row with View Toggle */
.gallery-search-row {
  display: flex;
  gap: var(--spacing-3);
  align-items: center;
  margin-bottom: var(--spacing-4);
}

.gallery-search-input {
  flex: 1;
  border-radius: var(--radius-xl) !important;
  border: 2px solid var(--border-color) !important;
  padding: var(--spacing-3) var(--spacing-5) !important;
  font-size: var(--font-size-base) !important;
  transition: all var(--transition-base);
  background: var(--bg-secondary);
}

.gallery-search-input:focus {
  border-color: var(--color-primary) !important;
  box-shadow: 0 0 0 4px rgba(59, 130, 246, 0.15) !important;
  background: var(--bg-primary);
  outline: none;
}

/* View Toggle Buttons */
.gallery-view-toggle {
  display: flex;
  background: var(--bg-secondary);
  border-radius: var(--radius-lg);
  padding: 4px;
  gap: 2px;
  border: 1px solid var(--border-color);
}

.view-toggle-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border: none;
  background: transparent;
  border-radius: var(--radius-md);
  cursor: pointer;
  color: var(--text-tertiary);
  transition: all var(--transition-fast);
}

.view-toggle-btn:hover {
  color: var(--text-primary);
  background: var(--bg-tertiary);
}

.view-toggle-btn.active {
  background: var(--color-primary);
  color: white;
  box-shadow: var(--shadow-sm);
}

/* ========================================
   CATEGORY CHIPS - HORIZONTAL SCROLL
   ======================================== */

.gallery-category-chips {
  display: flex;
  gap: var(--spacing-2);
  overflow-x: auto;
  padding: var(--spacing-2) 0;
  margin: 0 calc(-1 * var(--spacing-6));
  padding-left: var(--spacing-6);
  padding-right: var(--spacing-6);
  scrollbar-width: none;
  -ms-overflow-style: none;
  scroll-behavior: smooth;
  -webkit-overflow-scrolling: touch;
}

.gallery-category-chips::-webkit-scrollbar {
  display: none;
}

.category-chip {
  flex-shrink: 0;
  padding: var(--spacing-2) var(--spacing-4);
  border-radius: 999px;
  border: 1.5px solid var(--border-color);
  background: var(--bg-primary);
  color: var(--text-secondary);
  font-size: var(--font-size-sm);
  font-weight: 500;
  cursor: pointer;
  transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
  white-space: nowrap;
  display: flex;
  align-items: center;
  gap: var(--spacing-2);
}

.category-chip:hover {
  border-color: var(--color-primary);
  color: var(--color-primary);
  transform: translateY(-1px);
}

.category-chip.active {
  background: var(--color-primary);
  border-color: var(--color-primary);
  color: white;
  box-shadow: 0 4px 12px rgba(59, 130, 246, 0.35);
  transform: translateY(-1px);
}

.category-chip .chip-count {
  background: rgba(255, 255, 255, 0.25);
  padding: 2px 8px;
  border-radius: 999px;
  font-size: var(--font-size-xs);
  font-weight: 600;
}

.category-chip.active .chip-count {
  background: rgba(255, 255, 255, 0.3);
}

/* ========================================
   CATEGORIES VIEW (Grid of Categories)
   ======================================== */

.gallery-categories-view {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
  gap: var(--spacing-4);
  padding: var(--spacing-4) 0;
}

.category-card {
  background: linear-gradient(135deg, var(--bg-primary) 0%, var(--bg-secondary) 100%);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-xl);
  padding: var(--spacing-5);
  cursor: pointer;
  transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  gap: var(--spacing-3);
  position: relative;
  overflow: hidden;
}

.category-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--color-primary), var(--color-primary-light));
  opacity: 0;
  transition: opacity var(--transition-fast);
}

.category-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 12px 24px rgba(0, 0, 0, 0.12);
  border-color: var(--color-primary);
}

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

.category-card-icon {
  width: 60px;
  height: 60px;
  background: linear-gradient(135deg, var(--color-primary-lighter), var(--bg-tertiary));
  border-radius: var(--radius-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.75rem;
}

.category-card-title {
  font-size: var(--font-size-sm);
  font-weight: 600;
  color: var(--text-primary);
  line-height: 1.3;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.category-card-count {
  background: var(--color-primary);
  color: white;
  padding: 4px 12px;
  border-radius: 999px;
  font-size: var(--font-size-xs);
  font-weight: 600;
}

/* ========================================
   LIST VIEW (Collapsible Sections)
   ======================================== */

.gallery-list-view {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-3);
  padding: var(--spacing-4) 0;
}

.gallery-section {
  background: var(--bg-primary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: all var(--transition-base);
}

.gallery-section:hover {
  border-color: var(--color-primary-light);
}

.gallery-section-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--spacing-4) var(--spacing-5);
  cursor: pointer;
  transition: all var(--transition-fast);
  gap: var(--spacing-3);
  user-select: none;
}

.gallery-section-header:hover {
  background: var(--bg-secondary);
}

.gallery-section-left {
  display: flex;
  align-items: center;
  gap: var(--spacing-3);
  flex: 1;
  min-width: 0;
}

.gallery-section-icon {
  width: 44px;
  height: 44px;
  background: linear-gradient(135deg, var(--color-primary-lighter), var(--bg-tertiary));
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.25rem;
  flex-shrink: 0;
}

.gallery-section-title {
  font-size: var(--font-size-base);
  font-weight: 600;
  color: var(--text-primary);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.gallery-section-right {
  display: flex;
  align-items: center;
  gap: var(--spacing-3);
  flex-shrink: 0;
}

.gallery-section-count {
  background: var(--bg-tertiary);
  color: var(--text-secondary);
  padding: 4px 12px;
  border-radius: 999px;
  font-size: var(--font-size-xs);
  font-weight: 600;
}

.gallery-section-chevron {
  width: 24px;
  height: 24px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-tertiary);
  transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.gallery-section.expanded .gallery-section-chevron {
  transform: rotate(180deg);
}

.gallery-section-content {
  display: grid;
  grid-template-rows: 0fr;
  transition: grid-template-rows 0.35s cubic-bezier(0.4, 0, 0.2, 1);
}

.gallery-section.expanded .gallery-section-content {
  grid-template-rows: 1fr;
}

.gallery-section-inner {
  overflow: hidden;
}

.gallery-section-exams {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: var(--spacing-3);
  padding: 0 var(--spacing-5) var(--spacing-5);
}

/* ========================================
   EXAM CARDS (New Apple-style Design)
   ======================================== */

.gallery-card {
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: var(--spacing-4);
  display: flex;
  gap: var(--spacing-3);
  cursor: pointer;
  transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
  position: relative;
}

.gallery-card:hover {
  transform: translateY(-3px);
  box-shadow: 0 8px 20px rgba(0, 0, 0, 0.1);
  border-color: var(--color-primary);
  background: var(--bg-primary);
}

.gallery-card:active {
  transform: translateY(-1px);
}

.gallery-card-icon {
  font-size: 1.5rem;
  background: linear-gradient(135deg, var(--color-primary-lighter), var(--bg-tertiary));
  width: 44px;
  height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-md);
  flex-shrink: 0;
}

.gallery-card-content {
  flex: 1;
  min-width: 0;
  display: flex;
  flex-direction: column;
  gap: var(--spacing-2);
}

.gallery-card-title {
  margin: 0;
  font-size: var(--font-size-sm);
  font-weight: 600;
  color: var(--text-primary);
  line-height: 1.4;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.gallery-card-meta {
  font-size: var(--font-size-xs);
  color: var(--text-tertiary);
  margin: 0;
}

.gallery-card-action {
  display: flex;
  align-items: center;
  gap: var(--spacing-2);
  margin-top: auto;
}

.gallery-card-action .btn {
  flex: 1;
  padding: var(--spacing-2) var(--spacing-3);
  font-size: var(--font-size-xs);
  min-height: 32px;
}

/* ========================================
   EMPTY & LOADING STATES
   ======================================== */

.gallery-empty-state {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: var(--spacing-12) var(--spacing-6);
  text-align: center;
}

.gallery-empty-icon {
  font-size: 4rem;
  margin-bottom: var(--spacing-4);
  opacity: 0.6;
}

.gallery-empty-title {
  font-size: var(--font-size-xl);
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: var(--spacing-2);
}

.gallery-empty-subtitle {
  font-size: var(--font-size-base);
  color: var(--text-secondary);
}

/* ========================================
   BACK TO TOP - FILTERED VIEW HEADER
   ======================================== */

.filtered-view-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--spacing-4);
  background: linear-gradient(135deg, var(--color-primary-lighter), var(--bg-secondary));
  border-radius: var(--radius-lg);
  margin-bottom: var(--spacing-4);
  border: 1px solid var(--color-primary-light);
}

.filtered-view-title {
  display: flex;
  align-items: center;
  gap: var(--spacing-3);
}

.filtered-view-title h3 {
  margin: 0;
  font-size: var(--font-size-lg);
  color: var(--color-primary-dark);
}

.filtered-view-back {
  background: var(--bg-primary);
  border: 1px solid var(--border-color);
  padding: var(--spacing-2) var(--spacing-4);
  border-radius: var(--radius-md);
  font-size: var(--font-size-sm);
  font-weight: 500;
  color: var(--text-secondary);
  cursor: pointer;
  transition: all var(--transition-fast);
  display: flex;
  align-items: center;
  gap: var(--spacing-2);
}

.filtered-view-back:hover {
  border-color: var(--color-primary);
  color: var(--color-primary);
}

/* Category Title (kept for backwards compatibility) */
.category-title {
  color: var(--color-primary-dark);
}

/* ========================================
   GALLERY ANIMATIONS
   ======================================== */

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(10px);
  }

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

.gallery-card,
.category-card,
.gallery-section {
  animation: fadeInUp 0.3s ease-out;
  animation-fill-mode: both;
}

.gallery-card:nth-child(1) {
  animation-delay: 0.02s;
}

.gallery-card:nth-child(2) {
  animation-delay: 0.04s;
}

.gallery-card:nth-child(3) {
  animation-delay: 0.06s;
}

.gallery-card:nth-child(4) {
  animation-delay: 0.08s;
}

.gallery-card:nth-child(5) {
  animation-delay: 0.1s;
}

.gallery-card:nth-child(6) {
  animation-delay: 0.12s;
}

.category-card:nth-child(1) {
  animation-delay: 0.02s;
}

.category-card:nth-child(2) {
  animation-delay: 0.04s;
}

.category-card:nth-child(3) {
  animation-delay: 0.06s;
}

.category-card:nth-child(4) {
  animation-delay: 0.08s;
}

.category-card:nth-child(5) {
  animation-delay: 0.1s;
}

.category-card:nth-child(6) {
  animation-delay: 0.12s;
}

/* ========================================
   MOBILE RESPONSIVENESS
   ======================================== */

@media (max-width: 640px) {
  .gallery-nav-container {
    padding: var(--spacing-3) var(--spacing-4);
  }

  .gallery-search-row {
    flex-direction: column;
  }

  .gallery-view-toggle {
    align-self: flex-end;
  }

  .gallery-category-chips {
    margin: 0 calc(-1 * var(--spacing-4));
    padding-left: var(--spacing-4);
    padding-right: var(--spacing-4);
  }

  .gallery-categories-view {
    grid-template-columns: repeat(2, 1fr);
    gap: var(--spacing-3);
  }

  .gallery-section-exams {
    grid-template-columns: 1fr;
    padding: 0 var(--spacing-4) var(--spacing-4);
  }

  .category-card {
    padding: var(--spacing-4);
  }

  .category-card-icon {
    width: 50px;
    height: 50px;
    font-size: 1.5rem;
  }
}