/* ============================================
   Financial Modeling Course - Component Styles
   ============================================
   Interactive UI components for lecture content
   ============================================ */

/* ============================================
   Hero Section
   ============================================ */
.hero {
  background: linear-gradient(135deg, var(--primary-navy) 0%, var(--primary-blue) 50%, var(--primary-light) 100%);
  color: var(--white);
  padding: var(--space-16) 0;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: url("data:image/svg+xml,%3Csvg width='60' height='60' viewBox='0 0 60 60' xmlns='http://www.w3.org/2000/svg'%3E%3Cg fill='none' fill-rule='evenodd'%3E%3Cg fill='%23ffffff' fill-opacity='0.05'%3E%3Cpath d='M36 34v-4h-2v4h-4v2h4v4h2v-4h4v-2h-4zm0-30V0h-2v4h-4v2h4v4h2V6h4V4h-4zM6 34v-4H4v4H0v2h4v4h2v-4h4v-2H6zM6 4V0H4v4H0v2h4v4h2V6h4V4H6z'/%3E%3C/g%3E%3C/g%3E%3C/svg%3E");
  opacity: 0.3;
}

.hero-content {
  position: relative;
  z-index: 1;
  max-width: 800px;
  margin: 0 auto;
}

.hero-badge {
  display: inline-block;
  background-color: var(--accent-gold);
  color: var(--primary-navy);
  padding: var(--space-2) var(--space-4);
  border-radius: var(--radius-full);
  font-size: var(--text-sm);
  font-weight: 600;
  margin-bottom: var(--space-4);
  text-transform: uppercase;
  letter-spacing: 1px;
}

.hero-title {
  font-size: var(--text-5xl);
  font-weight: 700;
  margin-bottom: var(--space-4);
  color: var(--white);
  text-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
}

.hero-subtitle {
  font-size: var(--text-xl);
  opacity: 0.9;
  margin-bottom: var(--space-8);
}

.hero-meta {
  display: flex;
  justify-content: center;
  gap: var(--space-8);
  flex-wrap: wrap;
}

.hero-meta-item {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  font-size: var(--text-sm);
}

.hero-meta-icon {
  width: 20px;
  height: 20px;
  opacity: 0.8;
}

/* ============================================
   Slide Carousel / Slider
   ============================================ */
.slider-container {
  position: relative;
  overflow: hidden;
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-xl);
}

.slider-track {
  display: flex;
  transition: transform 0.5s ease-in-out;
}

.slide {
  min-width: 100%;
  padding: var(--space-8);
  background-color: var(--white);
}

.slide-content {
  max-width: 800px;
  margin: 0 auto;
  text-align: center;
}

.slide-image {
  width: 100%;
  max-height: 400px;
  object-fit: contain;
  margin-bottom: var(--space-6);
}

.slider-nav {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  width: 100%;
  display: flex;
  justify-content: space-between;
  padding: 0 var(--space-4);
  pointer-events: none;
}

.slider-btn {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background-color: var(--white);
  border: none;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--shadow-lg);
  transition: all var(--transition-fast);
  pointer-events: auto;
}

.slider-btn:hover {
  background-color: var(--primary-navy);
  color: var(--white);
}

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

.slider-dots {
  display: flex;
  justify-content: center;
  gap: var(--space-2);
  padding: var(--space-4);
  background-color: var(--gray-50);
}

.slider-dot {
  width: 12px;
  height: 12px;
  border-radius: 50%;
  border: none;
  background-color: var(--gray-300);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.slider-dot.active {
  background-color: var(--primary-navy);
  transform: scale(1.2);
}

/* ============================================
   Accordion
   ============================================ */
.accordion {
  border-radius: var(--radius-xl);
  overflow: hidden;
  box-shadow: var(--shadow-md);
}

.accordion-item {
  border-bottom: 1px solid var(--gray-200);
}

.accordion-item:last-child {
  border-bottom: none;
}

.accordion-header {
  width: 100%;
  padding: var(--space-5) var(--space-6);
  background-color: var(--white);
  border: none;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-family: var(--font-primary);
  font-size: var(--text-lg);
  font-weight: 500;
  color: var(--gray-700);
  text-align: left;
  transition: all var(--transition-fast);
}

.accordion-header:hover {
  background-color: var(--gray-50);
}

.accordion-item.active .accordion-header {
  background-color: var(--primary-navy);
  color: var(--white);
}

.accordion-icon {
  width: 24px;
  height: 24px;
  transition: transform var(--transition-base);
}

.accordion-item.active .accordion-icon {
  transform: rotate(180deg);
}

.accordion-content {
  max-height: 0;
  overflow: hidden;
  transition: max-height var(--transition-base);
  background-color: var(--white);
}

.accordion-item.active .accordion-content {
  max-height: 1000px;
}

.accordion-body {
  padding: var(--space-6);
  border-top: 1px solid var(--gray-100);
}

/* ============================================
   Tabs
   ============================================ */
.tabs-container {
  border-radius: var(--radius-xl);
  overflow: hidden;
  box-shadow: var(--shadow-md);
}

.tabs-nav {
  display: flex;
  background-color: var(--gray-100);
  border-bottom: 2px solid var(--gray-200);
  overflow-x: auto;
}

.tab-btn {
  padding: var(--space-4) var(--space-6);
  background: none;
  border: none;
  cursor: pointer;
  font-family: var(--font-primary);
  font-size: var(--text-base);
  font-weight: 500;
  color: var(--gray-600);
  white-space: nowrap;
  transition: all var(--transition-fast);
  position: relative;
}

.tab-btn::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 0;
  right: 0;
  height: 2px;
  background-color: transparent;
  transition: background-color var(--transition-fast);
}

.tab-btn:hover {
  color: var(--primary-navy);
  background-color: var(--gray-50);
}

.tab-btn.active {
  color: var(--primary-navy);
  background-color: var(--white);
}

.tab-btn.active::after {
  background-color: var(--accent-gold);
}

.tabs-content {
  background-color: var(--white);
}

.tab-panel {
  display: none;
  padding: var(--space-6);
  animation: fadeIn 0.3s ease;
}

.tab-panel.active {
  display: block;
}

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

/* ============================================
   Quiz Component
   ============================================ */
.quiz-container {
  background-color: var(--white);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-lg);
  overflow: hidden;
}

.quiz-header {
  background: linear-gradient(135deg, var(--primary-navy) 0%, var(--primary-blue) 100%);
  color: var(--white);
  padding: var(--space-6);
}

.quiz-title {
  color: var(--white);
  margin-bottom: var(--space-2);
}

.quiz-progress {
  display: flex;
  align-items: center;
  gap: var(--space-3);
}

.quiz-progress-text {
  font-size: var(--text-sm);
  opacity: 0.9;
}

.quiz-progress-bar {
  flex: 1;
  height: 6px;
  background-color: rgba(255, 255, 255, 0.3);
  border-radius: var(--radius-full);
  overflow: hidden;
}

.quiz-progress-fill {
  height: 100%;
  background-color: var(--accent-gold);
  transition: width var(--transition-base);
}

.quiz-body {
  padding: var(--space-8);
}

.quiz-question {
  font-size: var(--text-xl);
  margin-bottom: var(--space-6);
  color: var(--gray-800);
}

.quiz-options {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}

.quiz-option {
  display: flex;
  align-items: center;
  padding: var(--space-4) var(--space-5);
  background-color: var(--gray-50);
  border: 2px solid var(--gray-200);
  border-radius: var(--radius-lg);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.quiz-option:hover {
  border-color: var(--primary-light);
  background-color: var(--gray-100);
}

.quiz-option.selected {
  border-color: var(--primary-blue);
  background-color: rgba(66, 153, 225, 0.1);
}

.quiz-option.correct {
  border-color: var(--success);
  background-color: rgba(72, 187, 120, 0.1);
}

.quiz-option.incorrect {
  border-color: var(--error);
  background-color: rgba(245, 101, 101, 0.1);
}

.quiz-option-marker {
  width: 24px;
  height: 24px;
  border: 2px solid var(--gray-300);
  border-radius: 50%;
  margin-right: var(--space-4);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 600;
  font-size: var(--text-sm);
  color: var(--gray-500);
  flex-shrink: 0;
  transition: all var(--transition-fast);
}

.quiz-option.selected .quiz-option-marker {
  border-color: var(--primary-blue);
  background-color: var(--primary-blue);
  color: var(--white);
}

.quiz-option.correct .quiz-option-marker {
  border-color: var(--success);
  background-color: var(--success);
  color: var(--white);
}

.quiz-option.incorrect .quiz-option-marker {
  border-color: var(--error);
  background-color: var(--error);
  color: var(--white);
}

.quiz-option-text {
  flex: 1;
}

.quiz-feedback {
  margin-top: var(--space-6);
  padding: var(--space-4);
  border-radius: var(--radius-lg);
  display: none;
}

.quiz-feedback.show {
  display: block;
  animation: fadeIn 0.3s ease;
}

.quiz-feedback.correct {
  background-color: var(--success-light);
  border-left: 4px solid var(--success);
}

.quiz-feedback.incorrect {
  background-color: var(--error-light);
  border-left: 4px solid var(--error);
}

.quiz-footer {
  padding: var(--space-6);
  border-top: 1px solid var(--gray-200);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.quiz-result {
  text-align: center;
  padding: var(--space-8);
}

.quiz-score {
  font-size: var(--text-5xl);
  font-weight: 700;
  color: var(--primary-navy);
  margin-bottom: var(--space-4);
}

.quiz-message {
  font-size: var(--text-xl);
  color: var(--gray-600);
}

/* ============================================
   Flashcards
   ============================================ */
.flashcard-container {
  perspective: 1000px;
  max-width: 500px;
  margin: 0 auto;
}

.flashcard {
  position: relative;
  width: 100%;
  height: 300px;
  cursor: pointer;
  transform-style: preserve-3d;
  transition: transform 0.6s;
}

.flashcard.flipped {
  transform: rotateY(180deg);
}

.flashcard-face {
  position: absolute;
  width: 100%;
  height: 100%;
  backface-visibility: hidden;
  border-radius: var(--radius-xl);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: var(--space-8);
  box-shadow: var(--shadow-lg);
}

.flashcard-front {
  background: linear-gradient(135deg, var(--primary-navy) 0%, var(--primary-blue) 100%);
  color: var(--white);
}

.flashcard-back {
  background-color: var(--white);
  border: 2px solid var(--accent-gold);
  transform: rotateY(180deg);
}

.flashcard-label {
  font-size: var(--text-xs);
  text-transform: uppercase;
  letter-spacing: 1px;
  opacity: 0.7;
  margin-bottom: var(--space-2);
}

.flashcard-term {
  font-size: var(--text-2xl);
  font-weight: 600;
  text-align: center;
}

.flashcard-definition {
  font-size: var(--text-lg);
  text-align: center;
  color: var(--gray-700);
}

.flashcard-nav {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: var(--space-4);
  margin-top: var(--space-6);
}

.flashcard-counter {
  font-size: var(--text-sm);
  color: var(--gray-600);
}

/* ============================================
   Interactive Cards / Feature Cards
   ============================================ */
.feature-card {
  background-color: var(--white);
  border-radius: var(--radius-xl);
  padding: var(--space-6);
  box-shadow: var(--shadow-md);
  transition: all var(--transition-base);
  cursor: pointer;
  position: relative;
  overflow: hidden;
}

.feature-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 4px;
  background: linear-gradient(90deg, var(--accent-gold) 0%, var(--accent-gold-light) 100%);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--transition-base);
}

.feature-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-xl);
}

.feature-card:hover::before {
  transform: scaleX(1);
}

.feature-card-icon {
  width: 64px;
  height: 64px;
  background: linear-gradient(135deg, var(--primary-navy) 0%, var(--primary-blue) 100%);
  border-radius: var(--radius-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: var(--space-4);
  font-size: var(--text-2xl);
  color: var(--white);
}

.feature-card-title {
  font-size: var(--text-xl);
  margin-bottom: var(--space-2);
  color: var(--primary-navy);
}

.feature-card-description {
  color: var(--gray-600);
  margin-bottom: 0;
}

/* ============================================
   Interactive Timeline
   ============================================ */
.timeline {
  position: relative;
  padding-left: var(--space-8);
}

.timeline::before {
  content: '';
  position: absolute;
  left: 15px;
  top: 0;
  bottom: 0;
  width: 2px;
  background: linear-gradient(180deg, var(--accent-gold) 0%, var(--primary-navy) 100%);
}

.timeline-item {
  position: relative;
  padding-bottom: var(--space-8);
}

.timeline-item:last-child {
  padding-bottom: 0;
}

.timeline-marker {
  position: absolute;
  left: calc(-1 * var(--space-8) + 7px);
  width: 18px;
  height: 18px;
  background-color: var(--accent-gold);
  border: 3px solid var(--white);
  border-radius: 50%;
  box-shadow: var(--shadow-md);
}

.timeline-item.active .timeline-marker {
  background-color: var(--primary-navy);
  animation: pulse 2s infinite;
}

@keyframes pulse {
  0% { box-shadow: 0 0 0 0 rgba(26, 54, 93, 0.4); }
  70% { box-shadow: 0 0 0 10px rgba(26, 54, 93, 0); }
  100% { box-shadow: 0 0 0 0 rgba(26, 54, 93, 0); }
}

.timeline-content {
  background-color: var(--white);
  border-radius: var(--radius-lg);
  padding: var(--space-5);
  box-shadow: var(--shadow-md);
  margin-left: var(--space-4);
}

.timeline-title {
  font-size: var(--text-lg);
  font-weight: 600;
  color: var(--primary-navy);
  margin-bottom: var(--space-2);
}

.timeline-text {
  color: var(--gray-600);
  margin-bottom: 0;
}

/* ============================================
   Drag and Drop
   ============================================ */
.drag-container {
  display: flex;
  gap: var(--space-8);
  flex-wrap: wrap;
  justify-content: center;
}

.drag-column {
  flex: 1;
  min-width: 250px;
  max-width: 350px;
}

.drag-column-header {
  background: linear-gradient(135deg, var(--primary-navy) 0%, var(--primary-blue) 100%);
  color: var(--white);
  padding: var(--space-4);
  border-radius: var(--radius-lg) var(--radius-lg) 0 0;
  font-weight: 600;
  text-align: center;
}

.drag-column-body {
  background-color: var(--gray-50);
  border: 2px dashed var(--gray-300);
  border-top: none;
  border-radius: 0 0 var(--radius-lg) var(--radius-lg);
  min-height: 200px;
  padding: var(--space-4);
  transition: all var(--transition-fast);
}

.drag-column-body.drag-over {
  background-color: var(--info-light);
  border-color: var(--info);
}

.drag-item {
  background-color: var(--white);
  padding: var(--space-4);
  border-radius: var(--radius-md);
  margin-bottom: var(--space-2);
  box-shadow: var(--shadow-sm);
  cursor: grab;
  transition: all var(--transition-fast);
}

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

.drag-item.dragging {
  opacity: 0.5;
  cursor: grabbing;
}

.drag-item.correct {
  background-color: var(--success-light);
  border: 1px solid var(--success);
}

.drag-item.incorrect {
  background-color: var(--error-light);
  border: 1px solid var(--error);
}

/* ============================================
   Poll / Voting
   ============================================ */
.poll-container {
  background-color: var(--white);
  border-radius: var(--radius-xl);
  padding: var(--space-6);
  box-shadow: var(--shadow-md);
}

.poll-question {
  font-size: var(--text-xl);
  color: var(--primary-navy);
  margin-bottom: var(--space-6);
  text-align: center;
}

.poll-options {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}

.poll-option {
  position: relative;
  padding: var(--space-4);
  background-color: var(--gray-50);
  border: 2px solid var(--gray-200);
  border-radius: var(--radius-lg);
  cursor: pointer;
  transition: all var(--transition-fast);
  overflow: hidden;
}

.poll-option:hover {
  border-color: var(--primary-light);
}

.poll-option.selected {
  border-color: var(--primary-blue);
}

.poll-option-bar {
  position: absolute;
  top: 0;
  left: 0;
  height: 100%;
  background-color: rgba(66, 153, 225, 0.2);
  transition: width var(--transition-slow);
  z-index: 0;
}

.poll-option-content {
  position: relative;
  z-index: 1;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.poll-option-text {
  font-weight: 500;
}

.poll-option-percentage {
  font-weight: 600;
  color: var(--primary-navy);
}

.poll-total {
  text-align: center;
  margin-top: var(--space-4);
  font-size: var(--text-sm);
  color: var(--gray-600);
}

/* ============================================
   Discussion Prompt
   ============================================ */
.discussion-prompt {
  background: linear-gradient(135deg, var(--primary-navy) 0%, var(--primary-blue) 100%);
  color: var(--white);
  border-radius: var(--radius-xl);
  padding: var(--space-8);
  text-align: center;
  position: relative;
  overflow: hidden;
}

.discussion-prompt::before {
  content: '"';
  position: absolute;
  top: -20px;
  left: 20px;
  font-size: 120px;
  font-family: Georgia, serif;
  opacity: 0.1;
}

.discussion-icon {
  width: 60px;
  height: 60px;
  background-color: var(--accent-gold);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto var(--space-4);
  font-size: var(--text-2xl);
}

.discussion-label {
  font-size: var(--text-sm);
  text-transform: uppercase;
  letter-spacing: 1px;
  opacity: 0.8;
  margin-bottom: var(--space-2);
}

.discussion-question {
  font-size: var(--text-2xl);
  color: var(--white);
  margin-bottom: var(--space-4);
}

.discussion-hint {
  font-size: var(--text-sm);
  opacity: 0.8;
  font-style: italic;
}

/* ============================================
   Interactive Checklist
   ============================================ */
.checklist {
  background-color: var(--white);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-md);
  overflow: hidden;
}

.checklist-header {
  background-color: var(--gray-50);
  padding: var(--space-4) var(--space-6);
  border-bottom: 1px solid var(--gray-200);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.checklist-title {
  font-size: var(--text-lg);
  font-weight: 600;
  color: var(--primary-navy);
  margin-bottom: 0;
}

.checklist-progress {
  font-size: var(--text-sm);
  color: var(--gray-600);
}

.checklist-items {
  padding: var(--space-4);
}

.checklist-item {
  display: flex;
  align-items: flex-start;
  gap: var(--space-3);
  padding: var(--space-3);
  border-radius: var(--radius-md);
  transition: background-color var(--transition-fast);
}

.checklist-item:hover {
  background-color: var(--gray-50);
}

.checklist-checkbox {
  width: 24px;
  height: 24px;
  border: 2px solid var(--gray-300);
  border-radius: var(--radius-md);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  transition: all var(--transition-fast);
}

.checklist-item.checked .checklist-checkbox {
  background-color: var(--success);
  border-color: var(--success);
}

.checklist-checkbox svg {
  width: 16px;
  height: 16px;
  color: var(--white);
  opacity: 0;
  transition: opacity var(--transition-fast);
}

.checklist-item.checked .checklist-checkbox svg {
  opacity: 1;
}

.checklist-text {
  flex: 1;
  color: var(--gray-700);
  transition: all var(--transition-fast);
}

.checklist-item.checked .checklist-text {
  color: var(--gray-500);
  text-decoration: line-through;
}

/* ============================================
   Animated Counter / Stats
   ============================================ */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: var(--space-6);
}

.stat-card {
  background-color: var(--white);
  border-radius: var(--radius-xl);
  padding: var(--space-6);
  text-align: center;
  box-shadow: var(--shadow-md);
}

.stat-value {
  font-size: var(--text-4xl);
  font-weight: 700;
  color: var(--primary-navy);
  margin-bottom: var(--space-2);
}

.stat-label {
  font-size: var(--text-sm);
  color: var(--gray-600);
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.stat-icon {
  width: 48px;
  height: 48px;
  background: linear-gradient(135deg, var(--accent-gold) 0%, var(--accent-gold-light) 100%);
  border-radius: var(--radius-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto var(--space-4);
  font-size: var(--text-xl);
}

/* ============================================
   Tooltip
   ============================================ */
.tooltip-trigger {
  position: relative;
  cursor: help;
  border-bottom: 1px dashed var(--gray-400);
}

.tooltip {
  position: absolute;
  bottom: 100%;
  left: 50%;
  transform: translateX(-50%);
  background-color: var(--gray-800);
  color: var(--white);
  padding: var(--space-2) var(--space-4);
  border-radius: var(--radius-md);
  font-size: var(--text-sm);
  white-space: nowrap;
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition-fast);
  z-index: var(--z-tooltip);
}

.tooltip::after {
  content: '';
  position: absolute;
  top: 100%;
  left: 50%;
  transform: translateX(-50%);
  border: 6px solid transparent;
  border-top-color: var(--gray-800);
}

.tooltip-trigger:hover .tooltip {
  opacity: 1;
  visibility: visible;
  bottom: calc(100% + 10px);
}

/* ============================================
   Modal
   ============================================ */
.modal-backdrop {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: rgba(0, 0, 0, 0.5);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: var(--z-modal-backdrop);
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition-base);
}

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

.modal {
  background-color: var(--white);
  border-radius: var(--radius-xl);
  max-width: 600px;
  width: 90%;
  max-height: 90vh;
  overflow-y: auto;
  box-shadow: var(--shadow-2xl);
  transform: scale(0.9);
  transition: transform var(--transition-base);
}

.modal-backdrop.active .modal {
  transform: scale(1);
}

.modal-header {
  padding: var(--space-6);
  border-bottom: 1px solid var(--gray-200);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.modal-title {
  font-size: var(--text-xl);
  margin-bottom: 0;
}

.modal-close {
  width: 32px;
  height: 32px;
  border: none;
  background-color: var(--gray-100);
  border-radius: 50%;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all var(--transition-fast);
}

.modal-close:hover {
  background-color: var(--gray-200);
}

.modal-body {
  padding: var(--space-6);
}

.modal-footer {
  padding: var(--space-6);
  border-top: 1px solid var(--gray-200);
  display: flex;
  justify-content: flex-end;
  gap: var(--space-3);
}

/* ============================================
   Notification / Toast
   ============================================ */
.toast-container {
  position: fixed;
  bottom: var(--space-6);
  right: var(--space-6);
  z-index: var(--z-tooltip);
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}

.toast {
  background-color: var(--gray-800);
  color: var(--white);
  padding: var(--space-4) var(--space-6);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-xl);
  display: flex;
  align-items: center;
  gap: var(--space-3);
  animation: slideInRight 0.3s ease;
}

@keyframes slideInRight {
  from {
    transform: translateX(100%);
    opacity: 0;
  }
  to {
    transform: translateX(0);
    opacity: 1;
  }
}

.toast.success {
  background-color: var(--success);
}

.toast.error {
  background-color: var(--error);
}

.toast.warning {
  background-color: var(--warning);
}

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

.toast-message {
  flex: 1;
}

.toast-close {
  background: none;
  border: none;
  color: var(--white);
  cursor: pointer;
  opacity: 0.7;
  transition: opacity var(--transition-fast);
}

.toast-close:hover {
  opacity: 1;
}

/* ============================================
   Code Block with Copy
   ============================================ */
.code-block {
  position: relative;
  background-color: var(--gray-800);
  border-radius: var(--radius-lg);
  overflow: hidden;
}

.code-header {
  background-color: var(--gray-700);
  padding: var(--space-2) var(--space-4);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.code-language {
  font-size: var(--text-xs);
  color: var(--gray-400);
  text-transform: uppercase;
}

.code-copy-btn {
  background: none;
  border: none;
  color: var(--gray-400);
  cursor: pointer;
  font-size: var(--text-sm);
  display: flex;
  align-items: center;
  gap: var(--space-2);
  transition: color var(--transition-fast);
}

.code-copy-btn:hover {
  color: var(--white);
}

.code-content {
  padding: var(--space-4);
  overflow-x: auto;
}

.code-content code {
  font-family: var(--font-mono);
  font-size: var(--text-sm);
  color: var(--gray-100);
  background: none;
  padding: 0;
}

/* ============================================
   Excel Demo Container
   ============================================ */
.excel-demo {
  background-color: var(--white);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-lg);
  overflow: hidden;
}

.excel-toolbar {
  background-color: var(--gray-100);
  padding: var(--space-3) var(--space-4);
  display: flex;
  align-items: center;
  gap: var(--space-2);
  border-bottom: 1px solid var(--gray-200);
}

.excel-btn {
  width: 32px;
  height: 32px;
  border: none;
  background-color: transparent;
  border-radius: var(--radius-md);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background-color var(--transition-fast);
}

.excel-btn:hover {
  background-color: var(--gray-200);
}

.excel-formula-bar {
  flex: 1;
  background-color: var(--white);
  border: 1px solid var(--gray-300);
  border-radius: var(--radius-md);
  padding: var(--space-2) var(--space-3);
  font-family: var(--font-mono);
  font-size: var(--text-sm);
}

.excel-grid {
  overflow: auto;
  max-height: 400px;
}

.excel-table {
  width: 100%;
  border-collapse: collapse;
  font-size: var(--text-sm);
}

.excel-table th,
.excel-table td {
  border: 1px solid var(--gray-200);
  padding: var(--space-2) var(--space-3);
  text-align: left;
  min-width: 100px;
}

.excel-table th {
  background-color: var(--gray-50);
  font-weight: 500;
  color: var(--gray-600);
}

.excel-table td {
  font-family: var(--font-mono);
}

.excel-table td.highlight {
  background-color: var(--accent-gold-light);
}

.excel-table td.formula {
  color: var(--primary-blue);
}

/* ============================================
   Loading Spinner
   ============================================ */
.spinner {
  width: 40px;
  height: 40px;
  border: 3px solid var(--gray-200);
  border-top-color: var(--primary-navy);
  border-radius: 50%;
  animation: spin 1s linear infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

.loading-overlay {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: rgba(255, 255, 255, 0.9);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  z-index: var(--z-modal);
}

.loading-text {
  margin-top: var(--space-4);
  color: var(--gray-600);
}

/* ============================================
   Responsive Adjustments
   ============================================ */
@media (max-width: 768px) {
  .hero {
    padding: var(--space-10) 0;
  }
  
  .hero-title {
    font-size: var(--text-3xl);
  }
  
  .hero-meta {
    flex-direction: column;
    gap: var(--space-4);
  }
  
  .flashcard {
    height: 250px;
  }
  
  .drag-container {
    flex-direction: column;
  }
  
  .drag-column {
    max-width: 100%;
  }
  
  .tabs-nav {
    flex-wrap: nowrap;
  }
  
  .tab-btn {
    padding: var(--space-3) var(--space-4);
    font-size: var(--text-sm);
  }
  
  .modal {
    width: 95%;
    margin: var(--space-4);
  }
  
  .toast-container {
    left: var(--space-4);
    right: var(--space-4);
  }
}