/* ==========================================================================
   Single Knowledge Article & Technical Editorial Layout
   ========================================================================== */
.single-post-main {
  padding-block: var(--epna-space-2xl) var(--epna-space-4xl);
  background-color: #f8fafc;
}

.article-layout-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 340px;
  gap: var(--epna-space-2xl);
  align-items: start;
  margin-block-start: var(--epna-space-lg);
}

.technical-article-card {
  background-color: var(--epna-white);
  border: 1px solid #e2e8f0;
  border-radius: var(--epna-radius-lg);
  padding: 2.75rem;
  box-shadow: 0 4px 24px -2px rgba(15, 23, 42, 0.05);
}

/* Entry Header */
.technical-article-card .entry-header {
  margin-block-end: 1.5rem;
}

.technical-article-card .entry-title {
  font-size: 2.15rem;
  font-weight: 800;
  line-height: 1.45;
  color: #0f172a;
  margin: 0 0 1.25rem;
  letter-spacing: -0.01em;
}

.entry-meta-strip {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.85rem;
  font-size: 0.875rem;
  color: #64748b;
  padding-block-end: 1.25rem;
  border-block-end: 1px solid #f1f5f9;
}

.meta-item {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
}

.meta-icon {
  color: var(--epna-cyan);
  flex-shrink: 0;
}

.meta-divider {
  color: #cbd5e1;
}

/* Hero Visual Framed Card */
.article-hero-visual-card {
  background-color: #ffffff;
  border: 1px solid #e2e8f0;
  border-radius: var(--epna-radius-md);
  margin-block: 2rem;
  margin-inline: 0;
  overflow: hidden;
  box-shadow: 0 2px 12px rgba(15, 23, 42, 0.04);
}

.featured-hero-img {
  width: 100%;
  max-height: 440px;
  object-fit: contain;
  padding: 2rem;
  background-color: #ffffff;
  display: block;
  margin: 0 auto;
}

.hero-img-caption {
  background-color: #f8fafc;
  border-block-start: 1px solid #f1f5f9;
  padding: 0.65rem 1.25rem;
  font-size: 0.85rem;
  color: #64748b;
  text-align: center;
}

/* Key Takeaways / Executive Summary Box */
.article-key-takeaways {
  background: linear-gradient(135deg, rgba(6, 182, 212, 0.08) 0%, rgba(15, 23, 42, 0.02) 100%);
  border: 1px solid rgba(6, 182, 212, 0.35);
  border-inline-start: 4px solid var(--epna-cyan);
  border-radius: var(--epna-radius-md);
  padding: 1.5rem 1.75rem;
  margin-block: 2rem;
}

.takeaways-header {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  margin-block-end: 0.6rem;
}

.takeaways-icon {
  font-size: 1.35rem;
}

.takeaways-title {
  font-size: 1.05rem;
  font-weight: 700;
  color: #0f172a;
  margin: 0;
}

.takeaways-text {
  margin: 0;
  font-size: 0.985rem;
  line-height: 1.95;
  color: #334155;
}

/* Reading Typography */
.reading-content {
  font-size: 1.085rem;
  line-height: 2.15;
  color: #334155;
}

.reading-content h2 {
  font-size: 1.55rem;
  font-weight: 800;
  color: #0f172a;
  margin-block: 2.5rem 1.15rem;
  border-inline-start: 4px solid #0284c7;
  padding-inline-start: 0.85rem;
  line-height: 1.5;
}

.reading-content h3 {
  font-size: 1.25rem;
  font-weight: 700;
  color: #1e293b;
  margin-block: 2rem 0.85rem;
  line-height: 1.6;
}

.reading-content p {
  margin-block-end: 1.5rem;
}

.reading-content ul,
.reading-content ol {
  margin-block-end: 1.5rem;
  padding-inline-start: 1.5rem;
}

.reading-content li {
  margin-block: 0.45rem;
}

.reading-content blockquote {
  background-color: #f8fafc;
  border-inline-start: 4px solid var(--epna-cyan);
  padding: 1.15rem 1.5rem;
  margin-block: 1.75rem;
  border-radius: 0 var(--epna-radius-sm) var(--epna-radius-sm) 0;
  font-style: italic;
  color: #475569;
}

/* Share Toolbar */
.article-share-toolbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 1rem;
  padding-block: 1.25rem;
  margin-block-start: 2.75rem;
  border-block-start: 1px solid #f1f5f9;
  border-block-end: 1px solid #f1f5f9;
}

.share-label {
  font-size: 0.9rem;
  font-weight: 600;
  color: #475569;
}

.share-buttons-group {
  display: flex;
  align-items: center;
  gap: 0.6rem;
}

.share-btn {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  color: var(--epna-white);
  border: none;
  cursor: pointer;
  transition: transform 0.2s ease, opacity 0.2s ease, box-shadow 0.2s ease;
  text-decoration: none;
  position: relative;
}

.share-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 10px rgba(0, 0, 0, 0.15);
}

.share-whatsapp { background-color: #25d366; }
.share-telegram { background-color: #229ed9; }
.share-linkedin { background-color: #0077b5; }
.share-copy-btn {
  background-color: #0f172a;
  color: var(--epna-white);
}

.copy-tooltip {
  position: absolute;
  bottom: 125%;
  inset-inline-start: 50%;
  transform: translateX(calc(-50% * var(--epna-dir-factor, 1)));
  background: #0f172a;
  color: #ffffff;
  padding: 0.3rem 0.65rem;
  font-size: 0.75rem;
  border-radius: 4px;
  white-space: nowrap;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.2s ease;
}

.share-copy-btn:hover .copy-tooltip,
.share-copy-btn.copied .copy-tooltip {
  opacity: 1;
}

/* Direct Engineering Inquiry Banner */
.article-inquiry-banner {
  background: linear-gradient(135deg, #0f172a 0%, #1e293b 100%);
  color: var(--epna-white);
  border-radius: var(--epna-radius-lg);
  padding: 2.25rem;
  margin-block: 2.5rem;
  position: relative;
  overflow: hidden;
  box-shadow: 0 10px 30px rgba(15, 23, 42, 0.15);
}

.article-inquiry-banner::before {
  content: '';
  position: absolute;
  top: -50px;
  inset-inline-end: -50px;
  width: 180px;
  height: 180px;
  background: radial-gradient(circle, rgba(6, 182, 212, 0.25) 0%, transparent 70%);
  border-radius: 50%;
  pointer-events: none;
}

.banner-title {
  font-size: 1.35rem;
  font-weight: 800;
  color: var(--epna-white);
  margin: 0 0 0.85rem;
  line-height: 1.5;
}

.banner-desc {
  color: #cbd5e1;
  font-size: 0.95rem;
  line-height: 1.85;
  margin: 0 0 1.5rem;
}

.banner-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.85rem;
  align-items: center;
}

/* Author Signature Card */
.article-author-card {
  display: flex;
  align-items: center;
  gap: 1.25rem;
  background-color: #f8fafc;
  border: 1px solid #e2e8f0;
  border-radius: var(--epna-radius-md);
  padding: 1.35rem 1.5rem;
  margin-block-start: 2rem;
}

.author-avatar-badge {
  width: 54px;
  height: 54px;
  border-radius: 50%;
  background-color: #e2e8f0;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.6rem;
  flex-shrink: 0;
}

.author-name {
  font-size: 1.05rem;
  font-weight: 700;
  color: #0f172a;
  margin: 0 0 0.35rem;
}

.author-bio {
  font-size: 0.875rem;
  color: #64748b;
  line-height: 1.7;
  margin: 0;
}

/* Sticky Technical Sidebar */
.article-sidebar {
  position: relative;
}

.sidebar-sticky-wrap {
  position: sticky;
  top: 96px;
  display: flex;
  flex-direction: column;
  gap: var(--epna-space-xl);
}

.sidebar-widget {
  background-color: var(--epna-white);
  border: 1px solid #e2e8f0;
  border-radius: var(--epna-radius-lg);
  padding: 1.5rem;
  box-shadow: 0 4px 16px rgba(15, 23, 42, 0.04);
}

.widget-title {
  font-size: 1.05rem;
  font-weight: 700;
  color: #0f172a;
  display: flex;
  align-items: center;
  gap: 0.45rem;
  padding-block-end: 0.75rem;
  border-block-end: 1px solid #f1f5f9;
  margin: 0 0 1rem;
}

.widget-products-list {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  margin-block-end: 1.25rem;
}

.sidebar-product-item {
  display: flex;
  align-items: center;
  gap: 0.85rem;
  padding-block-end: 1rem;
  border-block-end: 1px dashed #f1f5f9;
}

.sidebar-product-item:last-child {
  border-block-end: none;
  padding-block-end: 0;
}

.sidebar-prod-thumb {
  width: 62px;
  height: 62px;
  border-radius: var(--epna-radius-sm);
  border: 1px solid #e2e8f0;
  background: #ffffff;
  overflow: hidden;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.sidebar-prod-img {
  width: 100%;
  height: 100%;
  object-fit: contain;
}

.sidebar-prod-icon {
  font-size: 1.5rem;
}

.sidebar-prod-schematic {
  width: 100%;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  background-color: #f8fafc;
  padding: 0.5rem;
}

.sidebar-prod-schematic svg {
  width: 38px;
  height: 38px;
  stroke: #0284c7;
}

.sidebar-prod-content {
  flex: 1;
  min-width: 0;
}

.sidebar-prod-cat {
  display: inline-block;
  font-size: 0.75rem;
  color: #0284c7;
  font-weight: 600;
  margin-block-end: 0.2rem;
}

.sidebar-prod-title {
  font-size: 0.875rem;
  font-weight: 700;
  margin: 0 0 0.35rem;
  line-height: 1.4;
}

.sidebar-prod-title a {
  color: #0f172a;
  text-decoration: none;
  display: -webkit-box;
  line-clamp: 2;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.sidebar-prod-title a:hover {
  color: #0284c7;
}

.sidebar-prod-link {
  font-size: 0.8rem;
  font-weight: 600;
  color: #0284c7;
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  gap: 0.25rem;
}

.widget-fast-helpline {
  background: linear-gradient(180deg, #ffffff 0%, #f8fafc 100%);
  border: 1px solid #cbd5e1;
  border-block-start: 4px solid var(--epna-cyan);
}

.helpline-title {
  font-size: 1.15rem;
  font-weight: 800;
  color: #0f172a;
  margin: 0 0 0.5rem;
}

.helpline-desc {
  font-size: 0.875rem;
  color: #64748b;
  line-height: 1.6;
  margin: 0 0 1rem;
}

.helpline-contact-list {
  list-style: none;
  padding: 0;
  margin: 0 0 1.25rem;
}

.helpline-contact-list li {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding-block: 0.35rem;
  font-size: 0.9rem;
  font-weight: 600;
  color: #1e293b;
}

.helpline-contact-list a {
  color: inherit;
  text-decoration: none;
}

.helpline-contact-list a:hover {
  color: #0284c7;
}

/* Bottom Related Articles Section */
.article-related-posts-section {
  margin-block-start: 4.5rem;
  padding-block-start: 3.5rem;
  border-block-start: 1px solid #e2e8f0;
}

.related-section-header {
  text-align: center;
  margin-block-end: 2.75rem;
}

.related-posts-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--epna-space-xl);
}

/* Responsive Editorial Layout */
@media (max-width: 1024px) {
  .article-layout-grid {
    grid-template-columns: 1fr;
  }

  .sidebar-sticky-wrap {
    position: static;
  }

  .related-posts-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  .technical-article-card {
    padding: 1.6rem;
  }

  .technical-article-card .entry-title {
    font-size: 1.65rem;
  }

  .featured-hero-img {
    max-height: 320px;
    padding: 1rem;
  }

  .related-posts-grid {
    grid-template-columns: 1fr;
  }

  .banner-actions {
    flex-direction: column;
    width: 100%;
  }

  .banner-actions .btn {
    width: 100%;
    justify-content: center;
  }

  .article-share-toolbar {
    flex-direction: column;
    align-items: flex-start;
  }
}