/**
 * EduFoundation Universal Photo Album & Accessible Lightbox System
 * WCAG 2.2 AA / AAA Compliant, RTL/LTR Bidirectional, Zero Image Distortion
 */

:root {
  --album-thumb-ratio: 4 / 3;
  --album-thumb-radius: 12px;
  --album-focus-ring: 3px solid #38BDF8;
  --album-focus-offset: 3px;
  --lb-backdrop: rgba(5, 17, 26, 0.94);
  --lb-surface: rgba(15, 43, 56, 0.96);
  --lb-z: 99999;
}

/* Album Section Container */
.edu-album-section {
  margin-block: 2.5rem;
  padding: clamp(1.25rem, 3vw, 2.25rem);
  background: var(--surface-glass, rgba(15, 43, 56, 0.65));
  border: 1px solid var(--border, rgba(56, 189, 248, 0.22));
  border-radius: 16px;
  box-shadow: var(--shadow-glass, 0 12px 36px rgba(0,0,0,0.3));
}

.edu-album-header {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  margin-bottom: 1.5rem;
}

.edu-album-title-group h3 {
  font-size: clamp(1.15rem, 2vw, 1.45rem);
  color: var(--text, #F0F8FF);
  margin: 0 0 0.35rem 0;
  display: flex;
  align-items: center;
  gap: 0.6rem;
}

.edu-album-title-group p {
  margin: 0;
  font-size: 0.92rem;
  color: var(--text-muted, #94A9B8);
}

.edu-album-social-link {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.6rem 1.1rem;
  border-radius: 999px;
  background: rgba(24, 119, 242, 0.15);
  border: 1px solid rgba(24, 119, 242, 0.45);
  color: #60A5FA;
  font-size: 0.88rem;
  font-weight: 600;
  text-decoration: none;
  transition: all 0.25s ease;
  min-height: 44px;
}

.edu-album-social-link:hover,
.edu-album-social-link:focus-visible {
  background: #1877F2;
  color: #FFFFFF;
  border-color: #1877F2;
  box-shadow: 0 4px 16px rgba(24, 119, 242, 0.4);
  transform: translateY(-2px);
}

/* Grid of Thumbnails */
.edu-album-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
  gap: clamp(0.75rem, 1.5vw, 1.25rem);
  list-style: none;
  margin: 0;
  padding: 0;
}

@media (min-width: 768px) {
  .edu-album-grid {
    grid-template-columns: repeat(auto-fill, minmax(190px, 1fr));
  }
}

.edu-album-card {
  position: relative;
  border-radius: var(--album-thumb-radius);
  overflow: hidden;
  background: rgba(7, 23, 34, 0.6);
  border: 1px solid var(--border, rgba(56, 189, 248, 0.22));
  transition: transform 0.3s cubic-bezier(0.16, 1, 0.3, 1), box-shadow 0.3s ease, border-color 0.3s ease;
}

.edu-album-card:hover {
  transform: translateY(-4px);
  border-color: var(--brand, #38BDF8);
  box-shadow: 0 10px 24px rgba(2, 132, 199, 0.25);
}

.edu-album-thumb-btn {
  display: block;
  width: 100%;
  aspect-ratio: var(--album-thumb-ratio);
  padding: 0;
  border: none;
  background: transparent;
  cursor: pointer;
  overflow: hidden;
  position: relative;
  text-align: inherit;
}

.edu-album-thumb-btn:focus-visible {
  outline: var(--album-focus-ring);
  outline-offset: -3px;
  border-radius: var(--album-thumb-radius);
}

.edu-album-thumb-img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
  transition: transform 0.45s ease;
}

.edu-album-card:hover .edu-album-thumb-img {
  transform: scale(1.06);
}

.edu-album-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(to top, rgba(5, 17, 26, 0.8) 0%, transparent 60%);
  display: flex;
  align-items: flex-end;
  padding: 0.75rem;
  opacity: 0.9;
  transition: opacity 0.25s ease;
}

.edu-album-overlay-badge {
  font-size: 0.75rem;
  font-weight: 600;
  color: #F0F8FF;
  background: rgba(2, 132, 199, 0.75);
  backdrop-filter: blur(4px);
  padding: 0.2rem 0.55rem;
  border-radius: 6px;
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
}

/* Lightbox Modal */
.edu-lb-modal {
  position: fixed;
  inset: 0;
  z-index: var(--lb-z);
  background: var(--lb-backdrop);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  display: flex;
  flex-direction: column;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.28s ease, visibility 0.28s ease;
}

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

.edu-lb-topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem clamp(1rem, 3vw, 2.5rem);
  background: rgba(5, 17, 26, 0.85);
  border-bottom: 1px solid var(--border, rgba(56, 189, 248, 0.22));
  flex-shrink: 0;
}

.edu-lb-title-wrap {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
}

.edu-lb-title {
  font-size: clamp(1rem, 1.8vw, 1.25rem);
  font-weight: 700;
  color: var(--text, #F0F8FF);
  margin: 0;
}

.edu-lb-counter {
  font-size: 0.85rem;
  color: var(--brand, #38BDF8);
  font-weight: 600;
}

.edu-lb-close-btn {
  background: rgba(255, 255, 255, 0.1);
  border: 1px solid rgba(255, 255, 255, 0.2);
  color: #FFFFFF;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.25rem;
  cursor: pointer;
  transition: all 0.2s ease;
}

.edu-lb-close-btn:hover,
.edu-lb-close-btn:focus-visible {
  background: #EF4444;
  border-color: #EF4444;
  color: #FFFFFF;
  outline: var(--album-focus-ring);
  outline-offset: 2px;
  transform: rotate(90deg);
}

.edu-lb-stage {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: space-between;
  position: relative;
  padding: clamp(0.5rem, 2vw, 1.5rem);
  overflow: hidden;
}

.edu-lb-main-view {
  flex: 1;
  height: 100%;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  position: relative;
}

.edu-lb-main-img {
  max-width: min(92vw, 1200px);
  max-height: calc(85vh - 180px);
  width: auto;
  height: auto;
  object-fit: contain;
  border-radius: 10px;
  box-shadow: 0 16px 48px rgba(0, 0, 0, 0.65);
  background: #000;
  transition: opacity 0.2s ease;
}

.edu-lb-caption {
  margin-top: 0.85rem;
  font-size: clamp(0.9rem, 1.4vw, 1.05rem);
  color: #E2E8F0;
  text-align: center;
  max-width: 800px;
  padding: 0.4rem 1rem;
  background: rgba(15, 43, 56, 0.8);
  border-radius: 8px;
  border: 1px solid rgba(56, 189, 248, 0.25);
}

.edu-lb-nav-btn {
  background: rgba(15, 43, 56, 0.85);
  border: 1px solid var(--border, rgba(56, 189, 248, 0.3));
  color: #F0F8FF;
  width: 52px;
  height: 52px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  cursor: pointer;
  z-index: 10;
  transition: all 0.2s ease;
  backdrop-filter: blur(8px);
  margin-inline: clamp(0.5rem, 1.5vw, 1.5rem);
  flex-shrink: 0;
}

.edu-lb-nav-btn:hover,
.edu-lb-nav-btn:focus-visible {
  background: var(--brand, #38BDF8);
  color: #071722;
  border-color: var(--brand, #38BDF8);
  outline: var(--album-focus-ring);
  outline-offset: 2px;
  transform: scale(1.1);
}

/* Thumbs Scrubber */
.edu-lb-thumbs-bar {
  display: flex;
  gap: 0.5rem;
  padding: 0.75rem 1rem;
  background: rgba(5, 17, 26, 0.95);
  border-top: 1px solid var(--border, rgba(56, 189, 248, 0.22));
  overflow-x: auto;
  scroll-behavior: smooth;
  justify-content: center;
  flex-shrink: 0;
  max-height: 90px;
}

@media (max-width: 640px) {
  .edu-lb-thumbs-bar {
    justify-content: flex-start;
  }
}

.edu-lb-thumb {
  width: 64px;
  height: 48px;
  flex-shrink: 0;
  border-radius: 6px;
  overflow: hidden;
  border: 2px solid transparent;
  cursor: pointer;
  opacity: 0.55;
  transition: all 0.2s ease;
  padding: 0;
  background: transparent;
}

.edu-lb-thumb.active,
.edu-lb-thumb:hover,
.edu-lb-thumb:focus-visible {
  opacity: 1;
  border-color: var(--brand, #38BDF8);
  transform: translateY(-2px);
  outline: none;
}

.edu-lb-thumb img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}