/**
 * LEARNING RESOURCES
 * Version: 37.11.4-PHASE3C
 * Date: 2025-01-14
 * 
 * Resource cards with filters, video thumbnails, study info, and metadata.
 * Supports videos, articles, studies, and interactive content types.
 * 
 * Dependencies:
 * - variables.css (design tokens)
 * - buttons.css (button styles)
 * 
 * Components:
 * - .resource-filters - Filter buttons for content types
 * - .resources-grid - Responsive grid (1-2 columns)
 * - .resource-card - Individual resource with type badges
 * - .video-thumbnail - Video preview with play overlay
 * - .study-info - Research study metadata
 */

/* ============================================
   LEARNING RESOURCES
   ============================================ */
.resource-filters {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-md);
  justify-content: center;
  margin-bottom: var(--space-2xl);
}

.resource-filters .filter-btn {
  padding: var(--space-sm) var(--space-lg);
  background: var(--surface);
  color: var(--text-primary);
  border: 2px solid var(--border-light);
  border-radius: var(--radius-full);
  font-size: var(--font-size-sm);
  font-weight: 600;
  transition: all 0.3s ease;
  cursor: pointer;
}

.resource-filters .filter-btn:hover {
  background: var(--primary);
  color: white;
  border-color: var(--primary);
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(102, 126, 234, 0.3);
}

.resource-filters .filter-btn.active {
  background: var(--primary-gradient);
  color: white;
  border-color: var(--primary);
  box-shadow: 0 4px 12px rgba(102, 126, 234, 0.4);
  transform: translateY(-2px);
}

.resources-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-sm);
  margin: 0 auto;
}

/* Tablet: 2 columns */
@media (min-width: 768px) {
  .resources-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-lg);
  }
}

.resource-card {
  background: var(--surface);
  border-radius: var(--radius-md);
  padding: var(--space-sm);
  box-shadow: 0 2px 4px rgba(0,0,0,0.06);
  transition: all var(--transition-fast);
  border: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  position: relative;
}

/* Tablet: increase padding slightly */
@media (min-width: 768px) {
  .resource-card {
    padding: var(--space-md);
  }
}

.resource-card:hover {
  box-shadow: 0 4px 12px rgba(0,0,0,0.12);
  transform: translateY(-2px);
  border-color: var(--primary);
}

/* Resource Type Badge */
.resource-type-badge {
  display: inline-flex;
  align-items: center;
  gap: var(--space-xs);
  padding: var(--space-xs) var(--space-sm);
  background: var(--background);
  border-radius: var(--radius-sm);
  font-size: var(--font-size-xs);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  margin-bottom: var(--space-sm);
  width: fit-content;
}

.resource-card.videos .resource-type-badge {
  background: rgba(243, 156, 18, 0.15);
  color: var(--secondary-dark);
}

.resource-card.articles .resource-type-badge {
  background: rgba(93, 173, 226, 0.15);
  color: var(--accent-dark);
}

.resource-card.studies .resource-type-badge {
  background: rgba(44, 62, 80, 0.1);
  color: var(--primary);
}

.resource-card.interactive .resource-type-badge {
  background: rgba(133, 193, 233, 0.2);
  color: var(--accent);
}

/* Resource Title */
.resource-card h3 {
  font-size: var(--font-size-base);
  line-height: var(--line-height-tight);
  margin: 0 0 var(--space-xs) 0;
  color: var(--text);
  font-weight: 600;
}

@media (min-width: 768px) {
  .resource-card h3 {
    font-size: var(--font-size-lg);
    margin: 0 0 var(--space-sm) 0;
  }
}

/* Resource Description */
.resource-description {
  font-size: var(--font-size-sm);
  line-height: var(--line-height-normal);
  color: var(--text-secondary);
  margin: 0 0 var(--space-sm) 0;
  flex-grow: 1;
}

/* Video Thumbnail */
.video-thumbnail {
  position: relative;
  width: 100%;
  margin: var(--space-sm) 0;
  border-radius: var(--radius-sm);
  overflow: hidden;
  aspect-ratio: 16 / 9;
  background: var(--background);
  max-height: 180px;
}

@media (min-width: 768px) {
  .video-thumbnail {
    max-height: 220px;
  }
}

.video-thumbnail img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

.play-overlay {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(0, 0, 0, 0.3);
  cursor: pointer;
  transition: background var(--transition-fast);
}

.play-overlay:hover {
  background: rgba(0, 0, 0, 0.5);
}

.play-overlay i {
  font-size: 2.5rem;
  color: white;
  opacity: 0.9;
  transition: all var(--transition-fast);
}

@media (min-width: 768px) {
  .play-overlay i {
    font-size: 3rem;
  }
}

.play-overlay:hover i {
  opacity: 1;
  transform: scale(1.1);
}

/* Study Info */
.study-info {
  background: var(--background);
  padding: var(--space-sm);
  border-radius: var(--radius-sm);
  margin: var(--space-sm) 0;
  font-size: var(--font-size-sm);
}

.study-info p {
  margin: 0 0 var(--space-xs) 0;
  line-height: var(--line-height-normal);
}

.study-info strong {
  color: var(--text);
  font-weight: 600;
}

.study-info ul {
  margin: var(--space-sm) 0;
  padding-left: var(--space-lg);
}

.study-info li {
  margin: var(--space-xs) 0;
  line-height: var(--line-height-normal);
  color: var(--text-secondary);
}

/* Resource Meta */
.resource-meta {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  padding-top: var(--space-sm);
  margin-top: auto;
  border-top: 1px solid var(--border);
  font-size: var(--font-size-xs);
  color: var(--text-secondary);
}

.resource-meta span {
  display: flex;
  align-items: center;
  gap: var(--space-xs);
}

.resource-meta i {
  font-size: var(--font-size-xs);
  opacity: 0.7;
}

/* Button Link */
.btn-link {
  background: transparent;
  color: var(--primary);
  border: none;
  padding: var(--space-sm) 0;
  font-size: var(--font-size-sm);
  font-weight: 600;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: var(--space-xs);
  transition: all var(--transition-fast);
  margin-top: auto;
}

.btn-link:hover {
  color: var(--primary-dark);
  gap: var(--space-sm);
}

.btn-link i {
  font-size: var(--font-size-xs);
  transition: transform var(--transition-fast);
}

.btn-link:hover i {
  transform: translateX(4px);
}