/* ==========================================================================
   VAGATABA DESIGN SYSTEM - Marketing Curriculum v4.0 Stylesheet
   Standard: vg-html v3.5 | Brand: VAGA
   ========================================================================== */

/* 1. CSS CUSTOM PROPERTIES (TOKENS) */
:root {
  --vaga-primary: #006949;
  --vaga-primary-dark: #004d36;
  --vaga-primary-light: #0f6849;
  --vaga-primary-bg: #e8f4f0;
  --vaga-primary-container: #d2ede2;
  --vaga-on-primary: #ffffff;

  --vaga-accent: #f26121;
  --vaga-accent-dark: #c94b12;
  --vaga-accent-light: #ff7e47;
  --vaga-accent-bg: #fdf0e9;
  --vaga-on-accent: #ffffff;

  --vaga-bg: #f8fafc;
  --vaga-bg-card: #ffffff;
  --vaga-bg-elevated: #f1f5f9;
  --vaga-bg-subtle: #f8fafc;
  --vaga-border: #e2e8f0;
  --vaga-border-subtle: #cbd5e1;
  --vaga-border-strong: #006949;

  --vaga-text-primary: #0f172a;
  --vaga-text-secondary: #334155;
  --vaga-text-muted: #64748b;

  --vaga-success: #16a34a;
  --vaga-success-bg: #f0fdf4;
  --vaga-warning: #eab308;
  --vaga-warning-bg: #fefce8;
  --vaga-danger: #dc2626;
  --vaga-danger-bg: #fef2f2;
  --vaga-info: #0284c7;
  --vaga-info-bg: #f0f9ff;
  --vaga-callout-info-bg: #e8f4f0;

  --vaga-radius-xs: 4px;
  --vaga-radius-sm: 6px;
  --vaga-radius-md: 10px;
  --vaga-radius-lg: 14px;
  --vaga-radius-xl: 20px;
  --vaga-radius-pill: 9999px;

  --vaga-shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
  --vaga-shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.08), 0 2px 4px -2px rgb(0 0 0 / 0.05);
  --vaga-shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.08), 0 4px 6px -4px rgb(0 0 0 / 0.05);

  --duration-short4: 200ms;
  --ease-standard: cubic-bezier(0.2, 0, 0, 1);

  --vaga-table-header: #f1f5f9;
  --vaga-table-row-hover: #f8fafc;
}

[data-theme="dark"] {
  --vaga-primary: #34d399;
  --vaga-primary-dark: #10b981;
  --vaga-primary-light: #6ee7b7;
  --vaga-primary-bg: #064e3b;
  --vaga-primary-container: #047857;
  --vaga-on-primary: #06241b;

  --vaga-accent: #fb923c;
  --vaga-accent-dark: #f97316;
  --vaga-accent-light: #fdba74;
  --vaga-accent-bg: #431407;
  --vaga-on-accent: #ffffff;

  --vaga-bg: #0b1120;
  --vaga-bg-card: #131c31;
  --vaga-bg-elevated: #1e293b;
  --vaga-bg-subtle: #0f172a;
  --vaga-border: #334155;
  --vaga-border-subtle: #1e293b;
  --vaga-border-strong: #34d399;

  --vaga-text-primary: #f8fafc;
  --vaga-text-secondary: #cbd5e1;
  --vaga-text-muted: #94a3b8;

  --vaga-success-bg: #064e3b;
  --vaga-warning-bg: #713f12;
  --vaga-danger-bg: #7f1d1d;
  --vaga-info-bg: #0c4a6e;
  --vaga-callout-info-bg: #1e293b;

  --vaga-table-header: #1e293b;
  --vaga-table-row-hover: #1e293b;
}

/* 2. BASE & RESET */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: 'Work Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', Arial, sans-serif;
  background-color: var(--vaga-bg);
  color: var(--vaga-text-primary);
  line-height: 1.65;
  font-size: 1rem;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

/* 3. READING PROGRESS BAR */
.reading-progress-bar {
  position: fixed;
  top: 0;
  left: 0;
  height: 3px;
  background: var(--vaga-accent);
  z-index: 1000;
  width: 0%;
  transition: width 0.1s ease-out;
}

/* 4. NAVBAR */
.vaga-navbar {
  position: sticky;
  top: 0;
  background-color: var(--vaga-bg-card);
  border-bottom: 1px solid var(--vaga-border);
  z-index: 900;
  box-shadow: var(--vaga-shadow-sm);
}

.vaga-navbar__inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0.75rem 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.vaga-brand {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  text-decoration: none;
  color: var(--vaga-primary);
}

.vaga-brand-logo-img {
  width: 36px;
  height: 36px;
  border-radius: var(--vaga-radius-sm);
}

.vaga-brand-title {
  font-size: 1.15rem;
  font-weight: 800;
  letter-spacing: 0.05em;
  color: var(--vaga-primary);
  display: block;
  line-height: 1.1;
}

.vaga-brand-subtitle {
  font-size: 0.75rem;
  font-weight: 500;
  color: var(--vaga-text-muted);
  display: block;
}

.vaga-nav-links {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  flex-wrap: wrap;
}

.vaga-nav-link {
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--vaga-text-secondary);
  text-decoration: none;
  padding: 0.4rem 0.75rem;
  border-radius: var(--vaga-radius-sm);
  transition: all var(--duration-short4) var(--ease-standard);
}

.vaga-nav-link:hover, .vaga-nav-link.active {
  background-color: var(--vaga-primary-bg);
  color: var(--vaga-primary);
}

.vaga-search-trigger {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  background-color: var(--vaga-bg-elevated);
  border: 1px solid var(--vaga-border);
  border-radius: var(--vaga-radius-pill);
  padding: 0.4rem 0.9rem;
  font-size: 0.8125rem;
  font-weight: 500;
  color: var(--vaga-text-muted);
  cursor: pointer;
  transition: all var(--duration-short4) var(--ease-standard);
}

.vaga-search-trigger:hover {
  border-color: var(--vaga-primary);
  color: var(--vaga-primary);
}

.vaga-theme-btn {
  background: none;
  border: 1px solid var(--vaga-border);
  border-radius: var(--vaga-radius-pill);
  padding: 0.4rem 0.75rem;
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  font-size: 0.8125rem;
  font-weight: 600;
  color: var(--vaga-text-secondary);
  cursor: pointer;
  transition: all var(--duration-short4) var(--ease-standard);
}

.vaga-theme-btn:hover {
  background-color: var(--vaga-bg-elevated);
  border-color: var(--vaga-border-strong);
}

/* 5. BREADCRUMB BAR */
.breadcrumb-bar {
  background-color: var(--vaga-bg-elevated);
  border-bottom: 1px solid var(--vaga-border);
  font-size: 0.8125rem;
}

.breadcrumb-bar__inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0.5rem 1.5rem;
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.4rem;
  color: var(--vaga-text-muted);
}

.breadcrumb-bar a {
  color: var(--vaga-primary);
  text-decoration: none;
  font-weight: 500;
}

.breadcrumb-separator {
  color: var(--vaga-text-muted);
}

/* 6. CONTAINER & CARDS */
.vaga-container {
  max-width: 1200px;
  margin: 2rem auto;
  padding: 0 1.5rem;
  min-height: calc(100vh - 280px);
}

.vaga-card {
  background-color: var(--vaga-bg-card);
  border: 1px solid var(--vaga-border);
  border-radius: var(--vaga-radius-lg);
  padding: 2.25rem;
  box-shadow: var(--vaga-shadow-sm);
  margin-bottom: 2rem;
}

/* 7. HERO & HEADERS */
.hero-card {
  background: linear-gradient(135deg, var(--vaga-primary-bg) 0%, var(--vaga-bg-card) 100%);
  border: 1px solid var(--vaga-border);
  border-left: 6px solid var(--vaga-primary);
  border-radius: var(--vaga-radius-lg);
  padding: 2.5rem;
  margin-bottom: 2rem;
}

.hero-title {
  font-size: 2.25rem;
  font-weight: 800;
  color: var(--vaga-primary-dark);
  line-height: 1.25;
  margin-bottom: 0.75rem;
}

.hero-subtitle {
  font-size: 1.1rem;
  color: var(--vaga-text-secondary);
  line-height: 1.6;
}

.article-hero {
  border-bottom: 1px solid var(--vaga-border);
  padding-bottom: 1.5rem;
  margin-bottom: 2rem;
}

.hero-tags {
  display: flex;
  gap: 0.5rem;
  flex-wrap: wrap;
  margin-bottom: 1rem;
}

.article-title {
  font-size: 2rem;
  font-weight: 800;
  line-height: 1.25;
  color: var(--vaga-primary);
  margin-bottom: 1.25rem;
  letter-spacing: -0.01em;
}

/* 8. HERO META GRID (0911 MATCH) */
.hero-meta-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1rem;
  margin-top: 1.25rem;
}

.meta-box {
  background-color: var(--vaga-bg-elevated);
  border-left: 4px solid var(--vaga-primary);
  border-radius: 0 var(--vaga-radius-md) var(--vaga-radius-md) 0;
  padding: 1rem 1.25rem;
}

.meta-box--accent {
  border-left-color: var(--vaga-accent);
}

.meta-box--info {
  border-left-color: var(--vaga-info);
}

.meta-box__label {
  font-size: 0.8125rem;
  font-weight: 700;
  text-transform: uppercase;
  color: var(--vaga-text-muted);
  letter-spacing: 0.03em;
  margin-bottom: 0.375rem;
}

.meta-box__value {
  font-size: 0.9375rem;
  color: var(--vaga-text-primary);
  line-height: 1.5;
}

/* 9. BADGES & CHIPS */
.badge {
  display: inline-flex;
  align-items: center;
  gap: 0.25rem;
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  padding: 0.3rem 0.65rem;
  border-radius: var(--vaga-radius-pill);
}

.badge--primary {
  background-color: var(--vaga-primary-bg);
  color: var(--vaga-primary);
  border: 1px solid var(--vaga-primary-container);
}

.badge--accent {
  background-color: var(--vaga-accent-bg);
  color: var(--vaga-accent-dark);
  border: 1px solid #fcd3b6;
}

.badge--green {
  background-color: var(--vaga-success-bg);
  color: var(--vaga-success);
  border: 1px solid #bbf7d0;
}

.badge--neutral {
  background-color: var(--vaga-bg-elevated);
  color: var(--vaga-text-secondary);
  border: 1px solid var(--vaga-border);
}

/* 10. KPI SCORECARD GRID */
.kpi-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 1rem;
  margin: 1.75rem 0;
}

.kpi-card {
  background-color: var(--vaga-bg-card);
  border: 1px solid var(--vaga-border);
  border-radius: var(--vaga-radius-md);
  padding: 1.25rem 1rem;
  text-align: center;
  box-shadow: var(--vaga-shadow-sm);
  transition: transform var(--duration-short4) var(--ease-standard), border-color var(--duration-short4);
}

.kpi-card:hover {
  border-color: var(--vaga-primary);
}

.kpi-value {
  font-size: 1.85rem;
  font-weight: 800;
  color: var(--vaga-primary);
  line-height: 1.1;
  margin-bottom: 0.35rem;
}

.kpi-label {
  font-size: 0.8125rem;
  font-weight: 600;
  color: var(--vaga-text-muted);
}

/* 11. ARTICLE CONTENT & PEDAGOGICAL CALLOUTS */
.article-body {
  font-size: 1.05rem;
  line-height: 1.75;
  color: var(--vaga-text-primary);
}

.article-body h2 {
  font-size: 1.55rem;
  font-weight: 800;
  color: var(--vaga-primary);
  margin-top: 2.75rem;
  margin-bottom: 1rem;
  padding-bottom: 0.5rem;
  border-bottom: 2px solid var(--vaga-primary-container);
  scroll-margin-top: 5rem;
}

.article-body h3 {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--vaga-text-primary);
  margin-top: 1.75rem;
  margin-bottom: 0.75rem;
  scroll-margin-top: 5rem;
}

.article-body h4 {
  font-size: 1.1rem;
  font-weight: 600;
  margin: 1.25rem 0 0.5rem;
}

.article-body p {
  margin-bottom: 1.25rem;
}

.article-body ul, .article-body ol {
  margin: 0 0 1.25rem 1.75rem;
}

.article-body li {
  margin-bottom: 0.4rem;
}

/* Callouts */
.callout {
  padding: 1.1rem 1.35rem;
  border-radius: var(--vaga-radius-md);
  margin: 1.5rem 0;
  border-left: 5px solid;
  font-size: 0.98rem;
  line-height: 1.6;
}

.callout p:last-child {
  margin-bottom: 0;
}

.callout--what {
  background-color: var(--vaga-primary-bg);
  border-left-color: var(--vaga-primary);
  color: var(--vaga-primary-dark);
}

.callout--story {
  background-color: var(--vaga-bg-elevated);
  border-left-color: var(--vaga-info);
  color: var(--vaga-text-primary);
}

.callout--how {
  background-color: var(--vaga-bg-elevated);
  border-left-color: var(--vaga-accent);
  color: var(--vaga-text-primary);
}

.callout--socratic {
  background-color: #fefce8;
  border-left-color: #ca8a04;
  color: #713f12;
}

.callout--warn {
  background-color: var(--vaga-danger-bg);
  border-left-color: var(--vaga-danger);
  color: #7f1d1d;
}

.callout--pin {
  background-color: var(--vaga-primary-bg);
  border-left-color: var(--vaga-primary);
  color: var(--vaga-primary-dark);
}

.callout--link {
  background-color: var(--vaga-info-bg);
  border-left-color: var(--vaga-info);
  color: #075985;
}

[data-theme="dark"] .callout--socratic {
  background-color: #2e2609;
  color: #fef08a;
  border-left-color: #eab308;
}

[data-theme="dark"] .callout--warn {
  background-color: #3b0d0c;
  color: #fca5a5;
  border-left-color: #ef4444;
}

[data-theme="dark"] .callout--what {
  background-color: #042f2e;
  color: #a7f3d0;
  border-left-color: #34d399;
}

[data-theme="dark"] .callout--story {
  background-color: #1e293b;
  color: #cbd5e1;
  border-left-color: #38bdf8;
}

[data-theme="dark"] .callout--how {
  background-color: #271408;
  color: #fdba74;
  border-left-color: #f97316;
}

[data-theme="dark"] .callout--pin {
  background-color: #042f2e;
  color: #a7f3d0;
  border-left-color: #34d399;
}

[data-theme="dark"] .callout--link {
  background-color: #082f49;
  color: #7dd3fc;
  border-left-color: #38bdf8;
}

/* 12. TABLES */
.vaga-table-wrapper {
  width: 100%;
  overflow-x: auto;
  margin: 1.5rem 0;
  border-radius: var(--vaga-radius-md);
  border: 1px solid var(--vaga-border);
  background-color: var(--vaga-bg-card);
  min-height: 0;
}

.vaga-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.9375rem;
  text-align: left;
}

.vaga-table th {
  background-color: var(--vaga-table-header);
  color: var(--vaga-primary);
  font-weight: 700;
  padding: 0.875rem 1rem;
  border-bottom: 2px solid var(--vaga-border);
  white-space: nowrap;
}

.vaga-table td {
  padding: 0.75rem 1rem;
  border-bottom: 1px solid var(--vaga-border);
  color: var(--vaga-text-primary);
  vertical-align: top;
}

.vaga-table tbody tr:hover {
  background-color: var(--vaga-table-row-hover);
}

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

/* 13. CODE & ASCII DIAGRAMS */
.article-body pre {
  background-color: var(--vaga-bg-elevated);
  border: 1px solid var(--vaga-border);
  border-radius: var(--vaga-radius-md);
  padding: 1.25rem;
  overflow-x: auto;
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
  font-size: 0.875rem;
  line-height: 1.5;
  color: var(--vaga-text-primary);
  margin: 1.5rem 0;
}

.article-body code {
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
  font-size: 0.875em;
  background-color: var(--vaga-bg-elevated);
  padding: 0.2em 0.4em;
  border-radius: var(--vaga-radius-xs);
  border: 1px solid var(--vaga-border-subtle);
  color: var(--vaga-primary-dark);
}

.article-body pre code {
  background-color: transparent;
  padding: 0;
  border: none;
  font-size: inherit;
  color: inherit;
}

/* 14. TOC BLOCK (0911 MATCH) */
.toc-card {
  background-color: var(--vaga-bg-elevated);
  border: 1px solid var(--vaga-border);
  border-radius: var(--vaga-radius-md);
  padding: 1.25rem 1.5rem;
  margin-bottom: 2.25rem;
}

.toc-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 1rem;
  padding-bottom: 0.5rem;
  border-bottom: 1px solid var(--vaga-border);
}

.toc-title {
  font-size: 1.0625rem;
  font-weight: 700;
  color: var(--vaga-primary);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.toc-list {
  list-style: none;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 0.5rem 1.25rem;
}

.toc-item a {
  display: inline-flex;
  align-items: center;
  color: var(--vaga-text-secondary);
  text-decoration: none;
  font-size: 0.875rem;
  padding: 0.25rem 0.5rem;
  border-radius: var(--vaga-radius-sm);
  transition: all var(--duration-short4) var(--ease-standard);
  width: 100%;
}

.toc-item a:hover {
  color: var(--vaga-primary);
  background-color: var(--vaga-bg-card);
}

.toc-item a::before {
  content: "➔";
  font-size: 0.75rem;
  margin-right: 0.5rem;
  color: var(--vaga-accent);
}

.toc-item.level-3 a {
  padding-left: 1.5rem;
  font-size: 0.8125rem;
  color: var(--vaga-text-muted);
}

.toc-item.level-3 a::before {
  content: "•";
  color: var(--vaga-text-muted);
}

/* 15. FOOTER & NAVIGATION BUTTONS */
.article-nav-footer {
  margin-top: 3rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--vaga-border);
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
  flex-wrap: wrap;
}

.vaga-btn-nav {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  background-color: var(--vaga-bg-card);
  border: 1px solid var(--vaga-border);
  color: var(--vaga-text-primary);
  padding: 0.6rem 1.2rem;
  border-radius: var(--vaga-radius-pill);
  font-size: 0.875rem;
  font-weight: 600;
  text-decoration: none;
  cursor: pointer;
  transition: all var(--duration-short4) var(--ease-standard);
}

.vaga-btn-nav:hover {
  border-color: var(--vaga-primary);
  color: var(--vaga-primary);
  background-color: var(--vaga-primary-bg);
}

.vaga-btn-companion {
  background-color: var(--vaga-primary-bg);
  border-color: var(--vaga-primary-container);
  color: var(--vaga-primary);
}

/* 16. SEARCH MODAL */
.search-modal-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(15, 23, 42, 0.6);
  backdrop-filter: blur(4px);
  z-index: 2000;
  display: none;
  align-items: flex-start;
  justify-content: center;
  padding-top: 15vh;
}

.search-modal-backdrop.is-open {
  display: flex;
}

.search-modal {
  background: var(--vaga-bg-card);
  border: 1px solid var(--vaga-border);
  border-radius: var(--vaga-radius-lg);
  width: 90%;
  max-width: 600px;
  box-shadow: var(--vaga-shadow-lg);
  overflow: hidden;
}

.search-modal-header {
  display: flex;
  align-items: center;
  padding: 1rem 1.25rem;
  border-bottom: 1px solid var(--vaga-border);
  gap: 0.75rem;
}

.search-input {
  flex: 1;
  background: none;
  border: none;
  font-size: 1.05rem;
  font-family: inherit;
  color: var(--vaga-text-primary);
  outline: none;
}

.search-results-list {
  max-height: 50vh;
  overflow-y: auto;
  padding: 0.5rem;
}

.search-result-item {
  display: block;
  padding: 0.75rem 1rem;
  text-decoration: none;
  border-radius: var(--vaga-radius-md);
  margin-bottom: 0.25rem;
  transition: background-color var(--duration-short4);
}

.search-result-item:hover {
  background-color: var(--vaga-primary-bg);
}

.search-result-title {
  font-weight: 700;
  color: var(--vaga-primary-dark);
  font-size: 0.95rem;
}

.search-result-category {
  font-size: 0.75rem;
  color: var(--vaga-text-muted);
  margin-top: 0.2rem;
}

/* 17. SITE FOOTER */
.vaga-site-footer {
  background-color: var(--vaga-bg-card);
  border-top: 1px solid var(--vaga-border);
  padding: 2rem 1.5rem;
  margin-top: 4rem;
  font-size: 0.875rem;
  color: var(--vaga-text-muted);
}

.vaga-site-footer__inner {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 1.5rem;
}

.vaga-site-footer a {
  color: var(--vaga-primary);
  text-decoration: none;
  font-weight: 500;
}

/* 18. CHART.JS VENN DIAGRAM COMPONENT (EXACT 0911 STANDARD) */
.chart-card {
  background-color: var(--vaga-bg-card);
  border: 1px solid var(--vaga-border);
  border-radius: var(--vaga-radius-lg);
  padding: 1.5rem;
  margin: 2rem 0;
  box-shadow: var(--vaga-shadow-sm);
}

.chart-card__header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  flex-wrap: wrap;
  gap: 1rem;
  margin-bottom: 1.25rem;
  padding-bottom: 1rem;
  border-bottom: 1px solid var(--vaga-border);
}

.chart-card__title {
  font-size: 1.25rem;
  font-weight: 800;
  color: var(--vaga-primary);
  margin: 0.375rem 0 0.25rem;
}

.chart-card__desc {
  font-size: 0.875rem;
  color: var(--vaga-text-muted);
  margin: 0;
}

.venn-interactive-chips {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-bottom: 1.25rem;
}

.venn-chip {
  display: inline-flex;
  align-items: center;
  gap: 0.375rem;
  padding: 0.375rem 0.75rem;
  border-radius: var(--vaga-radius-pill);
  font-size: 0.8125rem;
  font-weight: 600;
  background-color: var(--vaga-bg-elevated);
  color: var(--vaga-text-secondary);
  border: 1px solid var(--vaga-border);
  cursor: pointer;
  transition: all var(--duration-short4) var(--ease-standard);
  font-family: inherit;
}

.venn-chip:hover {
  background-color: var(--vaga-primary-bg);
  color: var(--vaga-primary);
  border-color: var(--vaga-primary-container);
}

.venn-chip.active {
  background-color: var(--vaga-primary);
  color: var(--vaga-on-primary);
  border-color: var(--vaga-primary-dark);
}

.chart-canvas-wrap {
  position: relative;
  width: 100%;
  height: 660px;
  min-height: 420px;
  margin-bottom: 1.25rem;
  border-radius: var(--vaga-radius-md);
  background: var(--vaga-bg-subtle);
  border: 1px solid var(--vaga-border-subtle);
  overflow: hidden;
}

.chart-canvas-wrap canvas,
#vennChartCanvas {
  display: block !important;
  width: 100% !important;
  height: 100% !important;
  max-width: 100% !important;
  max-height: 100% !important;
  box-sizing: border-box !important;
}

@media (max-width: 1024px) {
  .chart-canvas-wrap {
    height: 580px;
  }
}

@media (max-width: 768px) {
  .chart-canvas-wrap {
    height: 500px;
  }
}

@media (max-width: 480px) {
  .chart-canvas-wrap {
    height: 400px;
  }
}

.chart-fallback-note {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--vaga-bg-card);
  padding: 1.5rem;
  text-align: center;
}

.venn-detail-box {
  background-color: var(--vaga-bg-elevated);
  border-left: 4px solid var(--vaga-accent);
  border-radius: 0 var(--vaga-radius-md) var(--vaga-radius-md) 0;
  padding: 1rem 1.25rem;
  transition: all var(--duration-short4) var(--ease-standard);
}

.venn-detail-title {
  font-size: 1.0625rem;
  font-weight: 700;
  color: var(--vaga-primary);
  margin: 0.25rem 0 0.375rem;
}

.venn-detail-desc {
  font-size: 0.9375rem;
  color: var(--vaga-text-secondary);
  line-height: 1.6;
  margin: 0;
}

/* 19. BACK TO TOP */
.back-to-top {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  width: 2.75rem;
  height: 2.75rem;
  border-radius: var(--vaga-radius-pill);
  background-color: var(--vaga-primary);
  color: var(--vaga-on-primary);
  border: none;
  font-size: 1.2rem;
  font-weight: 700;
  cursor: pointer;
  box-shadow: var(--vaga-shadow-md);
  opacity: 0;
  visibility: hidden;
  transition: all var(--duration-short4) var(--ease-standard);
  z-index: 90;
  display: flex;
  align-items: center;
  justify-content: center;
}

.back-to-top.visible {
  opacity: 1;
  visibility: visible;
}

.back-to-top:hover {
  background-color: var(--vaga-accent);
}

/* 20. RESPONSIVE BREAKPOINTS */
@media (max-width: 768px) {
  .vaga-navbar__inner {
    padding: 0.5rem 1rem;
  }
  .vaga-card {
    padding: 1.5rem 1rem;
  }
  .hero-card {
    padding: 1.5rem 1rem;
  }
  .hero-title {
    font-size: 1.75rem;
  }
  .article-title {
    font-size: 1.5rem;
  }
  .toc-list {
    grid-template-columns: 1fr;
  }
}