/* ==========================================================================
   Blog Section - Production Ready Component
   ========================================================================== */

/* CSS Custom Properties - 8px Spacing System */
:root {
  /* Colors - Black, White, Gray Only */
  --blog-primary: #000000;
  --blog-secondary: #333333;
  --blog-accent: #000000;
  --blog-accent-hover: #333333;
  --blog-muted: #666666;
  --blog-light: #f5f5f5;
  --blog-bg: #ffffff;
  --blog-border: #e0e0e0;
  --blog-shadow: rgba(0, 0, 0, 0.06);
  --blog-shadow-hover: rgba(0, 0, 0, 0.12);
  
  /* Typography - Using Project Font (DM Sans) */
  --blog-font: 'DM Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --blog-font-size-sm: 0.875rem;
  --blog-font-size-base: 1rem;
  --blog-font-size-lg: 1.125rem;
  --blog-font-size-xl: 1.25rem;
  --blog-font-size-2xl: 1.5rem;
  
  /* Spacing - 8px system */
  --blog-space-xs: 4px;
  --blog-space-sm: 8px;
  --blog-space-md: 16px;
  --blog-space-lg: 24px;
  --blog-space-xl: 32px;
  --blog-space-2xl: 48px;
  
  /* Borders */
  --blog-radius-sm: 8px;
  --blog-radius-md: 12px;
  --blog-radius-lg: 16px;
  
  /* Transitions */
  --blog-transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

/* Note: DM Sans font is already loaded via blog.html */

/* ==========================================================================
   Blog Section Container
   ========================================================================== */
.blog-section {
  --blog-gutter: 24px;
  position: relative;
  padding: var(--blog-space-2xl) 0;
  background: var(--blog-bg);
  font-family: var(--blog-font);
  overflow: hidden;
}

.blog-section__container {
  max-width: 1400px;
  margin: 0 auto;
  padding: 0 var(--blog-space-lg);
}

@media (max-width: 768px) {
  .blog-section {
    padding: var(--blog-space-lg) 0;
  }
  
  .blog-section__container {
    padding: 0 var(--blog-space-sm);
  }
}

/* Section Header */
.blog-section__header {
  display: flex;
  justify-content: space-between;
  align-items: flex-end;
  margin-bottom: var(--blog-space-xl);
  gap: var(--blog-space-md);
  flex-wrap: wrap;
}

.blog-section__title-group {
  flex: 1;
  min-width: 280px;
}

.blog-section__label {
  display: inline-block;
  font-size: var(--blog-font-size-sm);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 1.5px;
  color: var(--blog-muted);
  margin-bottom: var(--blog-space-sm);
}

.blog-section__title {
  font-size: clamp(1.75rem, 4vw, 2.5rem);
  font-weight: 700;
  color: var(--blog-primary);
  margin: 0;
  line-height: 1.2;
}

.blog-section__description {
  font-size: var(--blog-font-size-base);
  color: var(--blog-muted);
  margin: var(--blog-space-sm) 0 0;
  max-width: 600px;
  line-height: 1.6;
}

@media (max-width: 767px) {
  .blog-section__header {
    margin-bottom: var(--blog-space-lg);
  }
  
  .blog-section__title {
    font-size: 1.5rem;
  }
  
  .blog-section__description {
    font-size: 0.875rem;
  }
  
  .blog-section__title-group {
    min-width: 100%;
  }
}

/* ==========================================================================
   Desktop & Tablet: CSS Grid Layout
   ========================================================================== */
.blog-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--blog-gutter);
  will-change: transform, opacity;
}

/* Tablet: 2 columns (768px - 1199px) */
@media (max-width: 1199px) and (min-width: 768px) {
  .blog-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

/* Desktop: 3 columns (≥1200px) */
@media (min-width: 1200px) {
  .blog-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

/* ==========================================================================
   Mobile: Carousel Layout (< 768px)
   ========================================================================== */
@media (max-width: 767px) {
  .blog-grid {
    display: flex;
    gap: 0;
    margin: 0 calc(var(--blog-space-sm) * -1);
    padding: 0 var(--blog-space-sm);
    
    /* Infinite scroll container */
    overflow-x: auto;
    scroll-snap-type: x mandatory;
    scroll-behavior: smooth;
    -webkit-overflow-scrolling: touch;
    scrollbar-width: none;
    -ms-overflow-style: none;
    
    /* Hide scrollbar */
    -ms-overflow-style: none;
    scrollbar-width: none;
  }
  
  .blog-grid::-webkit-scrollbar {
    display: none;
  }
  
  /* Carousel Animation - Auto-sliding */
  .blog-grid--carousel {
    animation: carousel-scroll 20s linear infinite;
    will-change: transform;
  }
  
  .blog-grid--carousel:hover,
  .blog-grid--carousel:focus-within {
    animation-play-state: paused;
  }
  
  @keyframes carousel-scroll {
    0% {
      transform: translateX(0);
    }
    100% {
      transform: translateX(-50%);
    }
  }
  
  /* Duplicate cards for infinite loop */
  .blog-grid--carousel .blog-card {
    flex-shrink: 0;
  }
}

/* ==========================================================================
   Blog Card Component
   ========================================================================== */
.blog-card {
  background: var(--blog-bg);
  border-radius: var(--blog-radius-lg);
  box-shadow: 0 2px 12px var(--blog-shadow);
  overflow: hidden;
  transition: transform var(--blog-transition), 
              box-shadow var(--blog-transition),
              opacity var(--blog-transition);
  height: 100%;
  display: flex;
  flex-direction: column;
  position: relative;
}

.blog-card:hover {
  transform: translateY(-8px);
  box-shadow: 0 12px 32px var(--blog-shadow-hover);
}

/* Mobile Carousel Card Styles */
@media (max-width: 767px) {
  .blog-card {
    scroll-snap-align: start;
    width: calc(100vw - 60px);
    max-width: 280px;
    margin-right: var(--blog-space-sm);
    flex: 0 0 calc(100% - 60px);
  }
  
  .blog-card:hover {
    transform: translateY(-4px);
  }
}

/* ==========================================================================
   Card Image Container - 16:9 Aspect Ratio
   ========================================================================== */
.blog-card__image-container {
  position: relative;
  width: 100%;
  padding-top: 56.25%; /* 16:9 aspect ratio */
  overflow: hidden;
  background: var(--blog-light);
}

.blog-card__image {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform var(--blog-transition);
  will-change: transform;
}

.blog-card:hover .blog-card__image {
  transform: scale(1.08);
}

/* Lazy Loading */
.blog-card__image[data-src] {
  opacity: 0;
  transition: opacity 0.4s ease, transform var(--blog-transition);
}

.blog-card__image[data-src].loaded {
  opacity: 1;
}

/* Category Badge */
.blog-card__category {
  position: absolute;
  top: var(--blog-space-sm);
  left: var(--blog-space-sm);
  display: inline-block;
  padding: 4px 10px;
  background: var(--blog-primary);
  color: #ffffff;
  font-size: 0.625rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  border-radius: var(--blog-radius-sm);
  z-index: 2;
  transition: background var(--blog-transition);
}

.blog-card__category:hover {
  background: var(--blog-secondary);
  color: #ffffff;
}

@media (max-width: 767px) {
  .blog-card__category {
    top: var(--blog-space-xs);
    left: var(--blog-space-xs);
    padding: 3px 8px;
    font-size: 0.5625rem;
  }
}

/* ==========================================================================
   Card Content
   ========================================================================== */
.blog-card__content {
  padding: var(--blog-space-md);
  display: flex;
  flex-direction: column;
  flex: 1;
}

@media (max-width: 767px) {
  .blog-card__content {
    padding: var(--blog-space-sm);
  }
}

/* Card Title */
.blog-card__title {
  font-size: var(--blog-font-size-lg);
  font-weight: 700;
  color: var(--blog-primary);
  margin: 0 0 var(--blog-space-xs);
  line-height: 1.35;
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

@media (max-width: 767px) {
  .blog-card__title {
    font-size: var(--blog-font-size-base);
    font-weight: 600;
    -webkit-line-clamp: 2;
  }
}

.blog-card__title a {
  color: inherit;
  text-decoration: none;
  transition: color var(--blog-transition);
}

.blog-card__title a:hover {
  color: var(--blog-secondary);
}

/* Card Excerpt */
.blog-card__excerpt {
  font-size: var(--blog-font-size-sm);
  color: var(--blog-muted);
  line-height: 1.6;
  margin: 0 0 var(--blog-space-sm);
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
  flex: 1;
}

@media (max-width: 767px) {
  .blog-card__excerpt {
    font-size: 0.8125rem;
    -webkit-line-clamp: 2;
  }
}

/* Card Meta */
.blog-card__meta {
  display: flex;
  align-items: center;
  gap: var(--blog-space-sm);
  margin-bottom: var(--blog-space-sm);
  padding-top: var(--blog-space-sm);
  border-top: 1px solid var(--blog-border);
}

.blog-card__author {
  display: flex;
  align-items: center;
  gap: var(--blog-space-xs);
}

.blog-card__author-image {
  width: 28px;
  height: 28px;
  border-radius: 50%;
  object-fit: cover;
  background: var(--blog-light);
}

.blog-card__author-name {
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--blog-secondary);
}

.blog-card__date {
  font-size: 0.75rem;
  color: var(--blog-muted);
}

/* Read More Link */
.blog-card__read-more {
  display: inline-flex;
  align-items: center;
  gap: var(--blog-space-xs);
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--blog-primary);
  text-decoration: none;
  transition: gap var(--blog-transition), color var(--blog-transition);
}

.blog-card__read-more:hover {
  color: var(--blog-secondary);
  gap: var(--blog-space-sm);
}

.blog-card__read-more svg {
  width: 14px;
  height: 14px;
  transition: transform var(--blog-transition);
}

.blog-card__read-more:hover svg {
  transform: translateX(3px);
}

/* ==========================================================================
   Accessibility - Focus States
   ========================================================================== */
.blog-card:focus-within {
  outline: 2px solid var(--blog-primary);
  outline-offset: 2px;
}

.blog-card__category:focus,
.blog-card__title a:focus,
.blog-card__read-more:focus {
  outline: 2px solid var(--blog-primary);
  outline-offset: 2px;
  border-radius: 2px;
}

/* Reduced Motion */
@media (prefers-reduced-motion: reduce) {
  .blog-card,
  .blog-card__image,
  .blog-card__category,
  .blog-card__title a,
  .blog-card__read-more,
  .blog-grid--carousel {
    transition: none;
    animation: none;
  }
  
  .blog-grid--carousel:hover {
    animation-play-state: paused;
  }
}

/* ==========================================================================
   Utility Classes
   ========================================================================== */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* ==========================================================================
   Loading Skeleton (Prevents Layout Shift)
   ========================================================================== */
.blog-card--skeleton {
  pointer-events: none;
}

.blog-card--skeleton .blog-card__image,
.blog-card--skeleton .blog-card__title,
.blog-card--skeleton .blog-card__excerpt,
.blog-card--skeleton .blog-card__meta {
  background: linear-gradient(90deg, 
    var(--blog-light) 25%, 
    #eeeeee 50%, 
    var(--blog-light) 75%
  );
  background-size: 200% 100%;
  animation: skeleton-loading 1.5s ease-in-out infinite;
  color: transparent;
  border-radius: 4px;
}

.blog-card--skeleton .blog-card__title {
  height: 1.5em;
  width: 90%;
}

.blog-card--skeleton .blog-card__excerpt {
  height: 3em;
  width: 100%;
}

.blog-card--skeleton .blog-card__meta {
  height: 28px;
  width: 60%;
}

@keyframes skeleton-loading {
  0% {
    background-position: 200% 0;
  }
  100% {
    background-position: -200% 0;
  }
}

/* ==========================================================================
   Performance Optimizations
   ========================================================================== */

/* GPU Acceleration for animations */
.blog-card,
.blog-card__image,
.blog-grid--carousel {
  transform: translateZ(0);
  backface-visibility: hidden;
}

/* Content visibility for long lists */
.blog-card {
  content-visibility: auto;
  contain-intrinsic-size: 0 380px;
}

/* Image loading optimization */
.blog-card__image[loading="lazy"] {
  loading: lazy;
}