/* ============================================
   Holiday Cards Portfolio
   A clean, gallery-focused design
   ============================================ */

/* --- CSS Custom Properties --- */
:root {
  /* Colors */
  --color-bg: #ffffff;
  --color-bg-subtle: #fafafa;
  --color-text: #1a1a1a;
  --color-text-muted: #666666;
  --color-text-light: #999999;
  --color-border: #e5e5e5;
  --color-border-light: #f0f0f0;
  --color-accent: #2c2c2c;
  --color-accent-hover: #000000;
  
  /* Typography */
  --font-display: 'Playfair Display', Georgia, serif;
  --font-body: 'Source Sans 3', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-mono: 'JetBrains Mono', monospace;
  
  /* Spacing */
  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  --space-2xl: 3rem;
  --space-3xl: 4rem;
  
  /* Layout */
  --sidebar-width: 200px;
  --sidebar-width-collapsed: 160px;
  --content-max-width: 1200px;
  --card-detail-max-width: 900px;
  
  /* Effects */
  --shadow-card: 0 2px 8px rgba(0, 0, 0, 0.08), 0 1px 2px rgba(0, 0, 0, 0.04);
  --shadow-card-hover: 0 8px 24px rgba(0, 0, 0, 0.12), 0 2px 8px rgba(0, 0, 0, 0.08);
  --transition-fast: 150ms ease;
  --transition-medium: 250ms ease;
}

/* --- Reset & Base --- */
*, *::before, *::after {
  box-sizing: border-box;
}

html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  margin: 0;
  padding: 0;
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.6;
  color: var(--color-text);
  background-color: var(--color-bg);
}

a {
  color: var(--color-accent);
  text-decoration: none;
  transition: color var(--transition-fast);
}

a:hover {
  color: var(--color-accent-hover);
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

/* --- Typography --- */
h1, h2, h3, h4 {
  font-family: var(--font-display);
  font-weight: 500;
  line-height: 1.2;
  margin: 0 0 var(--space-md) 0;
}

h1 {
  font-size: 2rem;
  letter-spacing: -0.02em;
}

h2 {
  font-size: 1.5rem;
}

h3 {
  font-size: 1.25rem;
}

p {
  margin: 0 0 var(--space-md) 0;
}

/* --- Layout --- */
.site-wrapper {
  display: flex;
  min-height: 100vh;
}

/* --- Sidebar --- */
.sidebar {
  width: var(--sidebar-width);
  flex-shrink: 0;
  padding: var(--space-xl);
  border-right: 1px solid var(--color-border-light);
  background-color: var(--color-bg);
  position: sticky;
  top: 0;
  height: 100vh;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
}

.site-title {
  font-family: var(--font-display);
  font-size: 1.1rem;
  font-weight: 500;
  color: var(--color-text);
  margin-bottom: var(--space-2xl);
  letter-spacing: 0.01em;
}

.site-title a {
  color: inherit;
}

.site-title a:hover {
  color: var(--color-text-muted);
}

/* Timeline Navigation */
.timeline-nav {
  flex: 1;
}

.timeline-nav h2 {
  font-family: var(--font-body);
  font-size: 0.7rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--color-text-light);
  margin-bottom: var(--space-md);
}

.decade-group {
  margin-bottom: var(--space-lg);
}

.decade-toggle {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  font-family: var(--font-body);
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--color-text);
  background: none;
  border: none;
  padding: var(--space-xs) 0;
  cursor: pointer;
  width: 100%;
  text-align: left;
  transition: color var(--transition-fast);
}

.decade-toggle:hover {
  color: var(--color-accent-hover);
}

.decade-toggle::before {
  content: '▸';
  font-size: 0.7rem;
  transition: transform var(--transition-fast);
  display: inline-block;
  width: 1em;
}

.decade-group.expanded .decade-toggle::before {
  transform: rotate(90deg);
}

.decade-years {
  display: none;
  padding-left: var(--space-lg);
  margin-top: var(--space-xs);
}

.decade-group.expanded .decade-years {
  display: block;
}

.year-link {
  display: block;
  font-size: 0.8rem;
  color: var(--color-text-muted);
  padding: var(--space-xs) 0;
  transition: color var(--transition-fast);
}

.year-link:hover,
.year-link.active {
  color: var(--color-accent-hover);
}

.year-link.active {
  font-weight: 600;
}

/* --- Main Content --- */
.main-content {
  flex: 1;
  min-width: 0;
  padding: var(--space-2xl) var(--space-2xl) var(--space-3xl);
}

/* --- Card Grid (Homepage) --- */
.page-header {
  margin-bottom: var(--space-2xl);
}

.page-header h1 {
  margin-bottom: var(--space-sm);
}

.page-subtitle {
  color: var(--color-text-muted);
  font-size: 1rem;
}

.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: var(--space-xl);
  max-width: var(--content-max-width);
}

.card-item {
  display: block;
  text-decoration: none;
  color: inherit;
}

.card-thumbnail {
  position: relative;
  aspect-ratio: 4 / 3;
  overflow: hidden;
  border-radius: 4px;
  box-shadow: var(--shadow-card);
  transition: box-shadow var(--transition-medium), transform var(--transition-medium);
  background-color: var(--color-bg-subtle);
}

.card-item:hover .card-thumbnail {
  box-shadow: var(--shadow-card-hover);
  transform: translateY(-2px);
}

.card-thumbnail img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform var(--transition-medium);
}

.card-item:hover .card-thumbnail img {
  transform: scale(1.02);
}

.card-info {
  padding: var(--space-md) var(--space-xs);
}

.card-title {
  font-family: var(--font-body);
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--color-text);
  margin-bottom: var(--space-xs);
}

.card-year {
  font-size: 0.8rem;
  color: var(--color-text-light);
  font-variant-numeric: tabular-nums;
}

/* --- Card Detail Pages --- */
.card-detail {
  max-width: var(--card-detail-max-width);
}

.card-detail-header {
  margin-bottom: var(--space-xl);
}

.card-detail-header h1 {
  margin-bottom: var(--space-xs);
}

.card-detail-year {
  font-size: 1rem;
  color: var(--color-text-muted);
}

.card-image-container {
  margin-bottom: var(--space-xl);
}

.card-image-main {
  border-radius: 4px;
  box-shadow: var(--shadow-card);
  overflow: hidden;
  background-color: var(--color-bg-subtle);
}

.card-image-main img {
  width: 100%;
  height: auto;
}

.card-view-label {
  text-align: center;
  font-size: 0.8rem;
  color: var(--color-text-light);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-top: var(--space-md);
}

/* Card Actions */
.card-actions {
  display: flex;
  justify-content: center;
  gap: var(--space-lg);
  margin-top: var(--space-xl);
  padding-top: var(--space-xl);
  border-top: 1px solid var(--color-border-light);
}

.card-action-link {
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
  font-size: 0.9rem;
  color: var(--color-text-muted);
  padding: var(--space-sm) var(--space-md);
  border-radius: 4px;
  transition: all var(--transition-fast);
}

.card-action-link:hover {
  color: var(--color-accent-hover);
  background-color: var(--color-bg-subtle);
}

.card-action-link.primary {
  color: var(--color-bg);
  background-color: var(--color-accent);
}

.card-action-link.primary:hover {
  background-color: var(--color-accent-hover);
  color: var(--color-bg);
}

/* Card Navigation (Prev/Next) */
.card-navigation {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-top: var(--space-2xl);
  padding-top: var(--space-xl);
  border-top: 1px solid var(--color-border-light);
}

.card-nav-link {
  display: flex;
  flex-direction: column;
  gap: var(--space-xs);
  color: var(--color-text-muted);
  font-size: 0.85rem;
  max-width: 45%;
}

.card-nav-link:hover {
  color: var(--color-accent-hover);
}

.card-nav-link.next {
  text-align: right;
  align-items: flex-end;
}

.card-nav-direction {
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--color-text-light);
}

.card-nav-title {
  font-weight: 500;
}

/* --- Making-Of Pages --- */
.making-of-content {
  max-width: 700px;
}

.making-of-content h1 {
  margin-bottom: var(--space-sm);
}

.making-of-breadcrumb {
  font-size: 0.85rem;
  color: var(--color-text-muted);
  margin-bottom: var(--space-xl);
}

.making-of-breadcrumb a {
  color: var(--color-text-muted);
}

.making-of-breadcrumb a:hover {
  color: var(--color-accent-hover);
}

.making-of-body {
  font-size: 1.05rem;
  line-height: 1.75;
}

.making-of-body p {
  margin-bottom: var(--space-lg);
}

.making-of-body img {
  margin: var(--space-xl) 0;
  border-radius: 4px;
  box-shadow: var(--shadow-card);
}

.making-of-body figure {
  margin: var(--space-xl) 0;
}

.making-of-body figcaption {
  font-size: 0.85rem;
  color: var(--color-text-muted);
  text-align: center;
  margin-top: var(--space-sm);
  font-style: italic;
}

/* Making-Of Pagination */
.making-of-pagination {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-top: var(--space-2xl);
  padding-top: var(--space-xl);
  border-top: 1px solid var(--color-border-light);
}

.pagination-link {
  font-size: 0.9rem;
  color: var(--color-text-muted);
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
}

.pagination-link:hover {
  color: var(--color-accent-hover);
}

.pagination-link.disabled {
  visibility: hidden;
}

/* --- Responsive Design --- */
@media (max-width: 900px) {
  .sidebar {
    width: var(--sidebar-width-collapsed);
    padding: var(--space-lg);
  }
  
  .site-title {
    font-size: 1rem;
  }
  
  .main-content {
    padding: var(--space-xl);
  }
  
  .card-grid {
    grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
    gap: var(--space-lg);
  }
}

@media (max-width: 700px) {
  .site-wrapper {
    flex-direction: column;
  }
  
  .sidebar {
    width: 100%;
    height: auto;
    position: relative;
    border-right: none;
    border-bottom: 1px solid var(--color-border-light);
    padding: var(--space-lg);
  }
  
  .site-title {
    margin-bottom: var(--space-md);
  }
  
  .timeline-nav {
    display: none;
  }
  
  .sidebar.nav-open .timeline-nav {
    display: block;
    margin-top: var(--space-md);
  }
  
  .mobile-nav-toggle {
    display: block;
    font-size: 0.8rem;
    color: var(--color-text-muted);
    background: none;
    border: 1px solid var(--color-border);
    padding: var(--space-sm) var(--space-md);
    border-radius: 4px;
    cursor: pointer;
  }
  
  .main-content {
    padding: var(--space-lg);
  }
  
  .card-grid {
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: var(--space-md);
  }
  
  .card-navigation {
    flex-direction: column;
    gap: var(--space-lg);
  }
  
  .card-nav-link {
    max-width: 100%;
    text-align: center !important;
    align-items: center !important;
  }
}

@media (min-width: 701px) {
  .mobile-nav-toggle {
    display: none;
  }
}

/* --- Utilities --- */
.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;
}

/* --- Site Version Footer --- */
.site-version {
  position: fixed;
  bottom: 0;
  right: 0;
  padding: 4px 8px;
  font-family: var(--font-body);
  font-size: 0.65rem;
  color: var(--color-text-muted);
  opacity: 0.4;
  transition: opacity 0.2s ease;
}

.site-version:hover {
  opacity: 1;
}