/* ==============================================================================
   Article Page Stylesheet
   Governed by Sections 13, 14, 15, 30-38, 73, 88, 91 of Master Specification
   ============================================================================== */

.article-header {
  padding: 40px 0 28px 0;
  border-bottom: 1px solid var(--border-color);
  margin-bottom: 36px;
}

.breadcrumbs {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-bottom: 16px;
}

.breadcrumbs a {
  color: var(--text-muted);
}

.breadcrumbs a:hover {
  color: var(--brand-primary);
}

.article-title {
  font-size: clamp(1.75rem, 5vw, 2.75rem);
  font-weight: 800;
  line-height: 1.25;
  color: var(--text-primary);
  margin-bottom: 16px;
  letter-spacing: -0.02em;
  word-break: break-word;
  overflow-wrap: break-word;
}

.article-subtitle {
  font-size: 1.2rem;
  line-height: 1.6;
  color: var(--text-secondary);
  margin-bottom: 24px;
}

.article-meta-bar {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 14px 0;
  border-top: 1px solid var(--border-subtle);
  font-size: 0.9rem;
}

.author-chip {
  display: flex;
  align-items: center;
  gap: 12px;
}

.author-chip svg, .author-chip img {
  border-radius: var(--radius-full);
}

.author-name {
  font-weight: 700;
  color: var(--text-primary);
}

.author-role {
  font-size: 0.8rem;
  color: var(--text-muted);
}

.article-meta-tags {
  display: flex;
  align-items: center;
  gap: 16px;
  color: var(--text-muted);
}

/* Article Hero SVG Diagram (Section 38 & 90) */
.article-hero-svg {
  width: 100%;
  max-width: 100%;
  box-sizing: border-box;
  max-height: 420px;
  border-radius: var(--radius-lg);
  overflow: hidden;
  margin-bottom: 40px;
  border: 1px solid var(--border-color);
  background: var(--bg-secondary);
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--shadow-md);
}

.article-hero-svg svg {
  width: 100%;
  max-width: 100%;
  height: auto;
  display: block;
}

/* Reader Note Banner (Section 13) */
.reader-note-banner {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  padding: 14px 18px;
  border-radius: var(--radius-md);
  background: var(--brand-glow);
  border: 1px solid rgba(37, 99, 235, 0.3);
  margin-bottom: 28px;
  font-size: 0.92rem;
  color: var(--text-primary);
  line-height: 1.5;
  width: 100%;
  max-width: 100%;
  box-sizing: border-box;
}

/* Single-Column Reader Layout with Top Table of Contents */
.article-layout {
  display: flex;
  flex-direction: column;
  gap: 36px;
  margin-bottom: 64px;
  width: 100%;
  max-width: 100%;
  box-sizing: border-box;
}

/* Table of Contents - Top of Article (Section 31) */
.article-toc,
.article-sidebar {
  width: 100%;
  max-width: 100%;
  box-sizing: border-box;
  margin-bottom: 8px;
}

.toc-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 22px 26px;
  width: 100%;
  box-sizing: border-box;
  box-shadow: var(--shadow-sm);
  transition: border-color var(--transition-smooth);
}

.toc-card:hover {
  border-color: rgba(37, 99, 235, 0.4);
}

.toc-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 16px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--border-subtle);
}

.toc-header-left {
  display: flex;
  align-items: center;
  gap: 10px;
}

.toc-title {
  font-size: 1rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin: 0;
  color: var(--text-primary);
}

.toc-badge {
  font-size: 0.72rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  padding: 3px 8px;
  border-radius: var(--radius-full);
  background: var(--brand-glow);
  color: var(--brand-primary);
  border: 1px solid rgba(37, 99, 235, 0.2);
}

.toc-list {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 10px 20px;
  margin: 0;
  padding: 0;
}

.toc-list li {
  margin: 0;
  padding: 0;
}

.toc-list a {
  color: var(--text-secondary);
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 12px;
  border-radius: var(--radius-sm);
  transition: all var(--transition-fast);
  word-break: break-word;
  overflow-wrap: break-word;
  text-decoration: none;
  font-size: 0.92rem;
  line-height: 1.45;
  background: var(--bg-secondary);
  border: 1px solid transparent;
}

.toc-list a:hover {
  color: var(--brand-primary);
  background: var(--brand-glow);
  border-color: rgba(37, 99, 235, 0.25);
  transform: translateX(3px);
}

.toc-list a.active {
  color: var(--brand-primary);
  font-weight: 600;
  background: var(--brand-glow);
  border-color: var(--brand-primary);
}

/* Executive Summary / Key Takeaways Callout (Section 32) */
.executive-summary {
  width: 100%;
  max-width: 100%;
  box-sizing: border-box;
  background: var(--brand-glow);
  border: 1px solid rgba(37, 99, 235, 0.3);
  border-left: 4px solid var(--brand-primary);
  border-radius: var(--radius-md);
  padding: 22px 24px;
  margin-bottom: 36px;
  overflow-wrap: break-word;
  word-break: break-word;
}

.executive-summary h3 {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--brand-primary);
  margin-bottom: 12px;
  overflow-wrap: break-word;
  word-break: break-word;
}

.executive-summary p {
  margin-bottom: 14px;
  line-height: 1.65;
  color: var(--text-primary);
  overflow-wrap: break-word;
}

.executive-summary ul {
  padding-left: 20px;
  color: var(--text-primary);
  margin-bottom: 0;
  max-width: 100%;
  overflow-wrap: break-word;
}

.executive-summary li {
  margin-bottom: 8px;
  line-height: 1.6;
  max-width: 100%;
  overflow-wrap: break-word;
}

/* Deep Technical Article Body (Sections 14, 15, 73) */
.article-body {
  min-width: 0;
  max-width: 100%;
  width: 100%;
  font-size: 1.05rem;
  line-height: 1.8;
  color: var(--text-primary);
  overflow-wrap: break-word;
  word-wrap: break-word;
  box-sizing: border-box;
}

#article-body-content {
  min-width: 0;
  max-width: 100%;
  width: 100%;
  box-sizing: border-box;
  overflow-wrap: break-word;
}

.article-body h2 {
  font-size: 1.65rem;
  font-weight: 800;
  margin: 48px 0 16px 0;
  color: var(--text-primary);
  scroll-margin-top: 100px;
  overflow-wrap: break-word;
  word-break: break-word;
  max-width: 100%;
}

.article-body h3 {
  font-size: 1.3rem;
  font-weight: 700;
  margin: 32px 0 12px 0;
  color: var(--text-primary);
  scroll-margin-top: 100px;
  overflow-wrap: break-word;
  word-break: break-word;
  max-width: 100%;
}

.article-body h4 {
  font-size: 1.1rem;
  font-weight: 700;
  margin: 24px 0 8px 0;
  color: var(--text-primary);
  overflow-wrap: break-word;
  word-break: break-word;
  max-width: 100%;
}

.article-body p {
  margin-bottom: 24px;
  max-width: 100%;
  overflow-wrap: break-word;
  word-wrap: break-word;
}

.article-body ul, .article-body ol {
  margin: 0 0 24px 28px;
  max-width: 100%;
  overflow-wrap: break-word;
}

.article-body li {
  margin-bottom: 8px;
  max-width: 100%;
  overflow-wrap: break-word;
}

.article-body img,
.article-body svg {
  max-width: 100%;
  height: auto;
  display: block;
}

/* Responsive Data Tables (Section 33) */
.table-container {
  width: 100%;
  max-width: 100%;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  margin: 32px 0;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-color);
  box-shadow: var(--shadow-sm);
  box-sizing: border-box;
}

table {
  width: 100%;
  min-width: 520px;
  border-collapse: collapse;
  text-align: left;
  font-size: 0.95rem;
}

th {
  background: var(--bg-secondary);
  color: var(--text-primary);
  font-weight: 700;
  padding: 14px 18px;
  border-bottom: 2px solid var(--border-color);
}

td {
  padding: 14px 18px;
  border-bottom: 1px solid var(--border-subtle);
  color: var(--text-secondary);
}

tbody tr:last-child td {
  border-bottom: none;
}

tbody tr:hover {
  background: var(--bg-secondary);
}

/* Code Blocks with Copy Button (Section 34) */
.code-wrapper {
  position: relative;
  margin: 28px 0;
  border-radius: var(--radius-md);
  overflow: hidden;
  background: #0f172a;
  border: 1px solid var(--border-color);
  width: 100%;
  max-width: 100%;
  box-sizing: border-box;
}

.code-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 8px 16px;
  background: #1e293b;
  border-bottom: 1px solid #334155;
  font-size: 0.8rem;
  font-family: var(--font-mono);
  color: #94a3b8;
}

.copy-code-btn {
  background: transparent;
  border: 1px solid #475569;
  color: #cbd5e1;
  padding: 4px 10px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  font-size: 0.75rem;
  font-family: var(--font-sans);
  transition: all var(--transition-fast);
}

.copy-code-btn:hover {
  background: #334155;
  color: #ffffff;
}

pre {
  margin: 0;
  padding: 18px;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  font-family: var(--font-mono);
  font-size: 0.9rem;
  line-height: 1.6;
  color: #e2e8f0;
  width: 100%;
  max-width: 100%;
  box-sizing: border-box;
  white-space: pre;
}

pre code {
  display: block;
  min-width: max-content;
  font-family: var(--font-mono);
  overflow-wrap: normal;
  word-break: normal;
}

code {
  font-family: var(--font-mono);
  overflow-wrap: break-word;
  word-break: break-word;
}

p code, li code, td code, th code, blockquote code {
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  padding: 2px 6px;
  border-radius: var(--radius-sm);
  font-size: 0.88em;
  color: var(--brand-primary);
  overflow-wrap: break-word;
  word-break: break-word;
}

/* Blockquotes */
.article-body blockquote {
  margin: 28px 0;
  padding: 16px 20px;
  border-left: 4px solid var(--brand-primary);
  background: var(--bg-surface);
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  font-style: italic;
  color: var(--text-secondary);
  width: 100%;
  max-width: 100%;
  box-sizing: border-box;
  overflow-wrap: break-word;
  word-break: break-word;
}

.article-body blockquote p {
  margin-bottom: 0;
  overflow-wrap: break-word;
  word-break: break-word;
}

/* Links inside Article Body */
.article-body a {
  color: var(--brand-primary);
  text-decoration: underline;
  text-underline-offset: 3px;
  overflow-wrap: break-word;
  word-break: break-word;
}

.article-body a:hover {
  filter: brightness(1.15);
}

/* ==============================================================================
   Scientific Notation & Mathematical Typography (KaTeX + Fallbacks)
   ============================================================================== */
.katex-display {
  display: block;
  margin: 28px 0;
  overflow-x: auto;
  overflow-y: hidden;
  padding: 14px 20px;
  background: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
  text-align: center;
  max-width: 100%;
  box-sizing: border-box;
  -webkit-overflow-scrolling: touch;
}

.katex {
  font-size: 1.08em;
  color: var(--text-primary);
  text-rendering: auto;
  line-height: 1.2;
}

.katex-display > .katex {
  display: inline-block;
  white-space: nowrap;
  max-width: 100%;
  text-align: initial;
}

.katex-html {
  overflow-wrap: normal;
  word-break: normal;
}

/* Fallback math styles */
.math-fallback-inline {
  font-family: "KaTeX_Math", "Cambria Math", "Latin Modern Math", "STIX Two Math", serif;
  font-style: italic;
  padding: 0 2px;
  color: var(--text-primary);
}

.math-fallback-inline sub,
.math-fallback-inline sup {
  font-style: normal;
  font-size: 0.78em;
}

.math-fallback-inline .math-text {
  font-style: normal;
  font-family: var(--font-sans);
}

.math-fallback-inline .math-bb {
  font-family: "KaTeX_AMS", "Cambria Math", serif;
  font-weight: 700;
  font-style: normal;
}

.math-fallback-block {
  display: block;
  margin: 24px 0;
  padding: 16px 20px;
  background: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  text-align: center;
  font-family: "KaTeX_Math", "Cambria Math", "Latin Modern Math", serif;
  font-size: 1.15rem;
  overflow-x: auto;
  box-sizing: border-box;
}

/* FAQ Accordion (Section 35) */
.faq-section {
  margin: 48px 0;
  width: 100%;
  max-width: 100%;
  box-sizing: border-box;
}

.faq-accordion {
  display: flex;
  flex-direction: column;
  gap: 12px;
  width: 100%;
  box-sizing: border-box;
}

.faq-item {
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  overflow: hidden;
  background: var(--bg-surface);
  width: 100%;
  box-sizing: border-box;
}

.faq-question {
  width: 100%;
  max-width: 100%;
  padding: 18px 20px;
  text-align: left;
  background: none;
  border: none;
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--text-primary);
  display: flex;
  justify-content: space-between;
  align-items: center;
  cursor: pointer;
  box-sizing: border-box;
  overflow-wrap: break-word;
  word-break: break-word;
}

.faq-question:hover {
  color: var(--brand-primary);
}

.faq-icon {
  font-size: 1.25rem;
  transition: transform var(--transition-smooth);
}

.faq-item.open .faq-icon {
  transform: rotate(45deg);
}

.faq-answer {
  display: none;
  padding: 0 20px 18px 20px;
  color: var(--text-secondary);
  line-height: 1.7;
  width: 100%;
  max-width: 100%;
  box-sizing: border-box;
  overflow-wrap: break-word;
  word-break: break-word;
}

.faq-item.open .faq-answer {
  display: block;
}

/* Citations & Verified Sources (Section 88) */
.article-sources {
  background: var(--bg-secondary);
  border-radius: var(--radius-md);
  padding: 24px;
  margin: 48px 0;
  border: 1px solid var(--border-color);
  width: 100%;
  max-width: 100%;
  box-sizing: border-box;
  overflow-wrap: break-word;
}

.article-sources h3 {
  font-size: 1.15rem;
  font-weight: 700;
  margin-bottom: 12px;
  color: var(--text-primary);
  overflow-wrap: break-word;
}

.sources-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 10px;
  width: 100%;
  box-sizing: border-box;
}

.source-item {
  font-size: 0.9rem;
  overflow-wrap: break-word;
  word-break: break-word;
  line-height: 1.6;
}

.source-item a {
  color: var(--brand-primary);
  overflow-wrap: break-word;
  word-break: break-word;
}

.source-badge {
  display: inline-block;
  text-transform: uppercase;
  font-size: 0.7rem;
  font-weight: 700;
  padding: 2px 6px;
  border-radius: var(--radius-sm);
  background: var(--border-color);
  margin-right: 6px;
  vertical-align: middle;
}

/* AI Transparency Disclosure (Section 91) */
.ai-disclosure-banner {
  display: flex;
  align-items: flex-start;
  gap: 16px;
  background: var(--bg-surface);
  border: 1px dashed var(--border-color);
  border-radius: var(--radius-md);
  padding: 16px 20px;
  margin: 36px 0;
  font-size: 0.85rem;
  color: var(--text-muted);
  width: 100%;
  max-width: 100%;
  box-sizing: border-box;
  overflow-wrap: break-word;
}

.ai-disclosure-banner strong {
  color: var(--text-primary);
}

/* Author Profile Box (Section 77) */
.author-box {
  display: flex;
  gap: 20px;
  align-items: center;
  background: var(--bg-secondary);
  border-radius: var(--radius-lg);
  padding: 24px;
  margin: 48px 0;
  border: 1px solid var(--border-color);
  width: 100%;
  max-width: 100%;
  box-sizing: border-box;
  overflow-wrap: break-word;
}

.author-box-avatar {
  flex-shrink: 0;
}

.author-box-bio {
  flex: 1;
  min-width: 0;
  overflow-wrap: break-word;
}

.author-box-bio h4 {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 6px;
  color: var(--text-primary);
  overflow-wrap: break-word;
}

.author-box-bio p {
  color: var(--text-secondary);
  font-size: 0.9rem;
  line-height: 1.55;
  margin: 0;
  overflow-wrap: break-word;
}

/* Responsive adjustment for article layout */
@media (max-width: 900px) {
  .article-layout {
    gap: 28px;
  }
}

@media (max-width: 640px) {
  .toc-card {
    padding: 16px;
  }
  .toc-list {
    grid-template-columns: 1fr;
    gap: 8px;
  }
  .toc-list a {
    padding: 7px 10px;
    font-size: 0.88rem;
  }
  .article-header {
    padding: 24px 0 18px 0;
    margin-bottom: 24px;
  }
  .article-meta-bar {
    flex-direction: column;
    align-items: flex-start;
    gap: 12px;
  }
  .author-chip {
    width: 100%;
  }
  .article-meta-tags {
    width: 100%;
    flex-wrap: wrap;
    gap: 10px;
  }
  .author-box {
    flex-direction: column;
    text-align: center;
    padding: 20px 16px;
    gap: 14px;
  }
  .code-wrapper {
    margin: 20px 0;
    border-radius: var(--radius-sm);
  }
  pre {
    padding: 14px;
    font-size: 0.85rem;
  }
  .article-body {
    font-size: 1rem;
    line-height: 1.7;
  }
  .executive-summary {
    padding: 18px 16px;
    margin-bottom: 24px;
  }
  .article-sources {
    padding: 18px 16px;
    margin: 32px 0;
  }
  .ai-disclosure-banner {
    padding: 14px 16px;
    flex-direction: column;
    gap: 8px;
  }
}