@import url('https://fonts.googleapis.com/css2?family=Space+Grotesk:wght@300;400;500;600;700&family=Inter:wght@300;400;500;600&family=JetBrains+Mono:wght@400;500&display=swap');

/* ─────────────────────────────────────────────
   DESIGN SYSTEM — Post-modern editorial
   ───────────────────────────────────────────── */

:root {
  --bg: #fafafa;
  --bg-alt: #ffffff;
  --bg-elevated: #ffffff;
  --bg-code: #0a0a0a;
  --surface: #f4f4f5;
  --ink: #09090b;
  --ink-secondary: #3f3f46;
  --ink-muted: #71717a;
  --ink-faint: #a1a1aa;
  --accent: #006ec6;
  --accent-hover: #0084e8;
  --accent-bg: rgba(0, 110, 198, 0.06);
  --orange: #f97316;
  --green: #22c55e;
  --border: #e4e4e7;
  --border-bold: #d4d4d8;
  --radius: 2px;
  --radius-md: 6px;
  --max-w: 1400px;
  --content-w: min(75vw, 1400px);
  --ease: cubic-bezier(0.16, 1, 0.3, 1);
  --dur: 0.35s;
  --font-display: 'Space Grotesk', system-ui, sans-serif;
  --font-body: 'Inter', system-ui, sans-serif;
  --font-mono: 'JetBrains Mono', monospace;
}

[data-theme="dark"] {
  --bg: #09090b;
  --bg-alt: #111113;
  --bg-elevated: #18181b;
  --surface: #1c1c1f;
  --ink: #fafafa;
  --ink-secondary: #a1a1aa;
  --ink-muted: #71717a;
  --ink-faint: #52525b;
  --accent: #38a3ff;
  --accent-hover: #60b5ff;
  --accent-bg: rgba(56, 163, 255, 0.08);
  --border: #27272a;
  --border-bold: #3f3f46;
}

*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-body);
  background: var(--bg);
  color: var(--ink);
  line-height: 1.6;
  transition: background var(--dur) var(--ease), color var(--dur) var(--ease);
}

::selection {
  background: var(--accent);
  color: white;
}

/* ─────────────────────────────────────────────
   READING PROGRESS
   ───────────────────────────────────────────── */

.reading-progress {
  position: fixed;
  top: 0;
  left: 0;
  height: 2px;
  background: var(--accent);
  z-index: 9999;
  transition: width 0.05s linear;
}

/* ─────────────────────────────────────────────
   NAVIGATION — Minimal, transparent
   ───────────────────────────────────────────── */

.navbar {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--bg);
  border-bottom: 1px solid var(--border);
  transition: all var(--dur) var(--ease);
}

.nav-container {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 clamp(1.5rem, 4vw, 3rem);
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 60px;
}

.nav-brand {
  display: flex;
  align-items: center;
  text-decoration: none;
}

.text-brand {
  color: var(--text-primary);
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
  font-size: 0.92rem;
  font-weight: 700;
  letter-spacing: -0.02em;
}

.copy-button {
  position: absolute;
  top: 0.6rem;
  right: 0.6rem;
  padding: 0.2rem 0.55rem;
  border: 1px solid rgba(255, 255, 255, 0.1);
  background: rgba(255, 255, 255, 0.06);
  color: #a1a1aa;
  cursor: pointer;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  transition: color 0.2s ease, border-color 0.2s ease;
}

.copy-button:hover,
.copy-button:focus-visible {
  border-color: rgba(255, 255, 255, 0.3);
  color: #e4e4e7;
}

.nav-brand .brand-logo {
  height: 30px;
  width: auto;
}

.nav-brand .brand-logo-white { display: none; }
.nav-brand .brand-logo-color { display: block; }

[data-theme="dark"] .nav-brand .brand-logo-white { display: block; }
[data-theme="dark"] .nav-brand .brand-logo-color { display: none; }

.nav-right {
  display: flex;
  align-items: center;
  gap: 1.5rem;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 2rem;
  list-style: none;
}

.nav-links a {
  text-decoration: none;
  color: var(--ink-muted);
  font-size: 0.85rem;
  font-weight: 500;
  letter-spacing: 0.01em;
  transition: color var(--dur) var(--ease);
  position: relative;
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 0;
  height: 1px;
  background: var(--ink);
  transition: width var(--dur) var(--ease);
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--ink);
}

.nav-links a:hover::after,
.nav-links a.active::after {
  width: 100%;
}

.theme-toggle {
  background: none;
  border: none;
  width: 32px;
  height: 32px;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--ink-muted);
  transition: color var(--dur) var(--ease);
  font-size: 1rem;
  border-radius: 50%;
}

.theme-toggle:hover {
  color: var(--ink);
}

.mobile-menu-btn {
  display: none;
  background: none;
  border: none;
  color: var(--ink);
  font-size: 1.25rem;
  cursor: pointer;
}

/* Hero is unused — page goes straight to content */

/* ─────────────────────────────────────────────
   BLOG LISTING — Editorial grid
   ───────────────────────────────────────────── */

.blog-section {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: clamp(2.5rem, 5vw, 4rem) clamp(1.5rem, 4vw, 3rem) clamp(4rem, 8vw, 8rem);
}

.section-header {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  margin-bottom: 2.5rem;
  padding-bottom: 2rem;
  border-bottom: 1px solid var(--border);
  flex-wrap: wrap;
  gap: 1rem;
}

.section-header-left {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
}

.section-header h1 {
  font-family: var(--font-display);
  font-size: 1.75rem;
  font-weight: 700;
  letter-spacing: -0.03em;
  color: var(--ink);
  line-height: 1.2;
}

.section-desc {
  font-size: 0.9rem;
  color: var(--ink-muted);
  line-height: 1.5;
}

.tag-filters {
  display: flex;
  gap: 0.25rem;
}

.tag-filter {
  padding: 0.35rem 0.9rem;
  border-radius: var(--radius);
  border: none;
  background: transparent;
  color: var(--ink-muted);
  font-family: var(--font-body);
  font-size: 0.8rem;
  font-weight: 500;
  cursor: pointer;
  transition: all var(--dur) var(--ease);
}

.tag-filter:hover {
  color: var(--ink);
}

.tag-filter.active {
  background: var(--ink);
  color: var(--bg);
}

/* ── Featured + Grid ── */
.blog-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.5rem;
}

/* ── Blog Card — Clean, editorial ── */
.blog-card {
  background: var(--bg-alt);
  border: 1px solid var(--border);
  overflow: hidden;
  text-decoration: none;
  color: inherit;
  display: flex;
  flex-direction: column;
  transition: all var(--dur) var(--ease);
  position: relative;
}

.blog-card:hover {
  border-color: var(--ink);
}

.blog-card:hover .card-image img {
  transform: scale(1.04);
}

.blog-card:hover .card-arrow {
  transform: translate(4px, -4px);
}

.card-image {
  position: relative;
  aspect-ratio: 16 / 10;
  overflow: hidden;
  background: var(--surface);
}

.card-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.6s var(--ease);
  filter: grayscale(15%) contrast(1.05);
}

.card-image .card-tag {
  position: absolute;
  bottom: 0.75rem;
  left: 0.75rem;
  background: var(--bg);
  color: var(--ink);
  padding: 0.2rem 0.55rem;
  font-family: var(--font-mono);
  font-size: 0.65rem;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  border: 1px solid var(--border);
}

.card-body {
  padding: 1.5rem;
  display: flex;
  flex-direction: column;
  flex: 1;
}

.card-meta {
  display: flex;
  align-items: center;
  gap: 1rem;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--ink-faint);
  margin-bottom: 0.75rem;
  letter-spacing: 0.02em;
}

.card-body h3 {
  font-family: var(--font-display);
  font-size: 1.35rem;
  font-weight: 600;
  line-height: 1.3;
  letter-spacing: -0.02em;
  margin-bottom: 0.75rem;
  transition: color var(--dur) var(--ease);
}

.card-body p {
  font-size: 0.9rem;
  color: var(--ink-secondary);
  line-height: 1.6;
  flex: 1;
}

.card-footer {
  padding: 1rem 1.5rem;
  border-top: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.card-author {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.card-author .avatar {
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: var(--accent);
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: 0.6rem;
  font-weight: 700;
  font-family: var(--font-display);
}

.card-author span {
  font-size: 0.8rem;
  font-weight: 500;
  color: var(--ink-muted);
}

.card-arrow {
  font-size: 1.1rem;
  color: var(--ink-faint);
  transition: all var(--dur) var(--ease);
  display: inline-block;
}

/* ─────────────────────────────────────────────
   ARTICLE HERO — Minimal, type-driven
   ───────────────────────────────────────────── */

.article-hero {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: clamp(3rem, 8vw, 6rem) clamp(1.5rem, 4vw, 3rem) clamp(2rem, 4vw, 3rem);
}

.article-hero-content {
  max-width: var(--content-w);
}

.article-breadcrumb {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--ink-faint);
  margin-bottom: 2rem;
  letter-spacing: 0.02em;
}

.article-breadcrumb a {
  color: var(--ink-muted);
  text-decoration: none;
  transition: color var(--dur) var(--ease);
}

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

.article-tag {
  display: inline-block;
  background: var(--accent-bg);
  color: var(--accent);
  padding: 0.25rem 0.65rem;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  margin-bottom: 1.25rem;
  border: 1px solid transparent;
}

.article-hero h1 {
  font-family: var(--font-display);
  font-size: clamp(2.25rem, 5vw, 3.25rem);
  font-weight: 700;
  color: var(--ink);
  line-height: 1.12;
  letter-spacing: -0.035em;
  margin-bottom: 1.5rem;
}

.article-meta-bar {
  display: flex;
  align-items: center;
  gap: 1.5rem;
  flex-wrap: wrap;
  font-size: 0.85rem;
  color: var(--ink-muted);
  padding-bottom: 2rem;
  border-bottom: 1px solid var(--border);
}

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

.article-meta-bar .author-info {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.article-meta-bar .author-avatar {
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: var(--accent);
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: 0.65rem;
  font-weight: 700;
  font-family: var(--font-display);
}

/* ─────────────────────────────────────────────
   ARTICLE CONTENT — Clean reading experience
   ───────────────────────────────────────────── */

.article-container {
  max-width: var(--content-w);
  margin: 0 auto;
  padding: 3rem clamp(1.5rem, 4vw, 3rem) 6rem;
}

.article-content {
  font-size: 1.05rem;
  line-height: 1.8;
  color: var(--ink-secondary);
}

.article-content h2 {
  font-family: var(--font-display);
  font-size: 1.65rem;
  font-weight: 600;
  color: var(--ink);
  margin: 3.5rem 0 1rem;
  letter-spacing: -0.025em;
  line-height: 1.2;
}

.article-content h2:first-child {
  margin-top: 0;
}

.article-content h3 {
  font-family: var(--font-display);
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--ink);
  margin: 2.5rem 0 0.75rem;
  letter-spacing: -0.015em;
}

.article-content h4 {
  font-family: var(--font-display);
  font-size: 1.05rem;
  font-weight: 600;
  color: var(--ink);
  margin: 2rem 0 0.5rem;
}

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

.article-content a {
  color: var(--accent);
  text-decoration: none;
  border-bottom: 1px solid rgba(0, 110, 198, 0.3);
  transition: border-color var(--dur) var(--ease);
}

.article-content a:hover {
  border-bottom-color: var(--accent);
}

.article-content strong {
  color: var(--ink);
  font-weight: 600;
}

.article-content em {
  font-style: italic;
}

.article-content ul,
.article-content ol {
  margin: 1rem 0 1.5rem;
  padding-left: 1.25rem;
}

.article-content li {
  margin-bottom: 0.5rem;
}

.article-content li::marker {
  color: var(--accent);
}

.article-content blockquote {
  border-left: 2px solid var(--ink);
  padding: 0 0 0 1.5rem;
  margin: 2rem 0;
  font-family: var(--font-display);
  font-size: 1.15rem;
  font-weight: 400;
  line-height: 1.6;
  color: var(--ink);
  font-style: normal;
}

.article-content pre {
  background: var(--bg-code);
  padding: 1.5rem;
  margin: 2rem 0;
  overflow-x: auto;
  border: 1px solid #27272a;
}

.article-content pre code {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  line-height: 1.7;
  color: #e4e4e7;
  background: none;
  padding: 0;
  border: none;
}

.article-content code {
  font-family: var(--font-mono);
  font-size: 0.85em;
  background: var(--surface);
  color: var(--accent);
  padding: 0.15em 0.4em;
  border: 1px solid var(--border);
}

.article-content img {
  max-width: 100%;
  margin: 2rem 0;
}

.article-content table {
  width: 100%;
  border-collapse: collapse;
  margin: 2rem 0;
  font-size: 0.875rem;
}

.article-content th,
.article-content td {
  padding: 0.75rem 1rem;
  text-align: left;
  border-bottom: 1px solid var(--border);
}

.article-content th {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--ink-muted);
}

.article-content tr:hover td {
  background: var(--accent-bg);
}

/* ─────────────────────────────────────────────
   INFO BOXES — Minimal, left-accent
   ───────────────────────────────────────────── */

.info-box {
  padding: 1rem 1.25rem;
  margin: 2rem 0;
  display: flex;
  gap: 0.75rem;
  align-items: flex-start;
  background: var(--surface);
  border-left: 2px solid;
}

.info-box .info-icon {
  font-size: 1rem;
  flex-shrink: 0;
  margin-top: 0.15rem;
}

.info-box.tip {
  border-left-color: var(--green);
  color: var(--ink-secondary);
}

.info-box.warning {
  border-left-color: var(--orange);
  color: var(--ink-secondary);
}

.info-box.note {
  border-left-color: var(--accent);
  color: var(--ink-secondary);
}

.info-box p {
  margin: 0;
  font-size: 0.9rem;
}

.info-box strong {
  color: var(--ink);
}

/* ─────────────────────────────────────────────
   TABLE OF CONTENTS — Sidebar
   ───────────────────────────────────────────── */

.toc-sidebar {
  position: fixed;
  left: max(calc((100vw - var(--content-w)) / 2 - 280px), 1rem);
  top: 100px;
  width: 200px;
  max-height: calc(100vh - 140px);
  overflow-y: auto;
  display: none;
}

@media (min-width: 1200px) {
  .toc-sidebar { display: block; }
}

.toc-sidebar h4 {
  font-family: var(--font-mono);
  font-size: 0.65rem;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--ink-faint);
  margin-bottom: 1rem;
}

.toc-sidebar ul {
  list-style: none;
  padding: 0;
}

.toc-sidebar li {
  margin-bottom: 0;
}

.toc-sidebar a {
  font-size: 0.78rem;
  color: var(--ink-faint);
  text-decoration: none;
  display: block;
  padding: 0.35rem 0 0.35rem 0.75rem;
  border-left: 1px solid var(--border);
  transition: all var(--dur) var(--ease);
  line-height: 1.4;
}

.toc-sidebar a:hover {
  color: var(--ink-secondary);
}

.toc-sidebar a.active {
  color: var(--ink);
  border-left-color: var(--ink);
}

/* ─────────────────────────────────────────────
   ARTICLE TAGS
   ───────────────────────────────────────────── */

.article-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin-top: 3rem;
  padding-top: 2rem;
  border-top: 1px solid var(--border);
}

.article-tags .tag {
  background: transparent;
  color: var(--ink-faint);
  padding: 0.3rem 0.7rem;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  border: 1px solid var(--border);
}

/* ─────────────────────────────────────────────
   SHARE SECTION
   ───────────────────────────────────────────── */

.share-section {
  margin-top: 2.5rem;
  padding: 2rem 0;
  text-align: left;
  border-top: 1px solid var(--border);
}

.share-section p {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--ink-faint);
  margin-bottom: 1rem;
}

.share-buttons {
  display: flex;
  gap: 0.5rem;
}

.share-btn {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.5rem 1rem;
  border: 1px solid var(--border);
  background: transparent;
  color: var(--ink-secondary);
  font-family: var(--font-body);
  font-size: 0.8rem;
  font-weight: 500;
  cursor: pointer;
  text-decoration: none;
  transition: all var(--dur) var(--ease);
}

.share-btn:hover {
  border-color: var(--ink);
  color: var(--ink);
}

/* ─────────────────────────────────────────────
   FOOTER
   ───────────────────────────────────────────── */

.site-footer {
  margin-top: 2rem;
  padding: 1.75rem clamp(1.5rem, 4vw, 3rem);
}

.footer-content {
  max-width: var(--max-w);
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 0.75rem;
}

.footer-left {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.footer-text {
  font-size: 0.78rem;
  color: var(--ink-faint);
  letter-spacing: 0.01em;
}

.footer-links {
  display: flex;
  gap: 1.25rem;
}

.footer-links a {
  color: var(--ink-faint);
  text-decoration: none;
  font-size: 0.78rem;
  font-weight: 400;
  transition: color var(--dur) var(--ease);
}

.footer-links a:hover {
  color: var(--ink);
}

/* ─────────────────────────────────────────────
   TIMELINE
   ───────────────────────────────────────────── */

.timeline {
  position: relative;
  padding-left: 2rem;
  margin: 2rem 0;
}

.timeline::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 1px;
  background: var(--border);
}

.timeline-item {
  position: relative;
  margin-bottom: 2rem;
  padding-left: 1.5rem;
}

.timeline-item::before {
  content: '';
  position: absolute;
  left: -2rem;
  top: 0.5rem;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--accent);
  transform: translateX(-3px);
}

.timeline-item .timeline-year {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 500;
  color: var(--accent);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  margin-bottom: 0.25rem;
}

.timeline-item h4 {
  font-family: var(--font-display);
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 0.25rem;
  color: var(--ink);
}

.timeline-item p {
  font-size: 0.9rem;
  color: var(--ink-secondary);
  margin: 0;
}

/* ─────────────────────────────────────────────
   COMPARISON CARDS
   ───────────────────────────────────────────── */

.comparison-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 1px;
  margin: 2rem 0;
  border: 1px solid var(--border);
  background: var(--border);
}

.comparison-card {
  background: var(--bg-alt);
  padding: 1.25rem;
}

.comparison-card h4 {
  font-family: var(--font-display);
  font-size: 0.9rem;
  font-weight: 600;
  margin-bottom: 0.5rem;
  color: var(--ink);
}

.comparison-card p {
  font-size: 0.85rem;
  color: var(--ink-secondary);
  margin: 0;
}

/* ─────────────────────────────────────────────
   COST TABLE
   ───────────────────────────────────────────── */

.cost-table {
  width: 100%;
  margin: 2rem 0;
  border-collapse: collapse;
  border: 1px solid var(--border);
}

.cost-table th {
  background: var(--ink);
  color: var(--bg);
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.cost-table tr:last-child td {
  font-weight: 700;
  background: var(--accent-bg);
  color: var(--accent);
}

/* ─────────────────────────────────────────────
   STEP CARDS
   ───────────────────────────────────────────── */

.step-card {
  background: var(--bg-alt);
  border: 1px solid var(--border);
  padding: 1.25rem 1.25rem 1.25rem 4rem;
  margin: 1rem 0;
  position: relative;
}

.step-card .step-number {
  position: absolute;
  left: 1.25rem;
  top: 1.25rem;
  width: 28px;
  height: 28px;
  background: var(--ink);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--bg);
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 0.75rem;
}

.step-card h4 {
  font-family: var(--font-display);
  font-size: 0.95rem;
  font-weight: 600;
  margin-bottom: 0.35rem;
  color: var(--ink);
}

.step-card p {
  font-size: 0.85rem;
  color: var(--ink-secondary);
  margin: 0;
}

/* ─────────────────────────────────────────────
   RESPONSIVE
   ───────────────────────────────────────────── */

@media (max-width: 768px) {
  .mobile-menu-btn { display: block; }

  .nav-links {
    display: none;
    position: absolute;
    top: 60px;
    left: 0;
    right: 0;
    background: var(--bg);
    border-bottom: 1px solid var(--border);
    flex-direction: column;
    padding: 1rem clamp(1.5rem, 4vw, 3rem);
    gap: 0.5rem;
  }

  .nav-links.open { display: flex; }

  .blog-grid {
    grid-template-columns: 1fr;
  }

  .card-image {
    aspect-ratio: 16 / 9;
  }

  .footer-content {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.5rem;
  }

  .share-buttons {
    flex-wrap: wrap;
  }
}

@media (max-width: 480px) {
  .article-meta-bar {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.5rem;
  }

  .tag-filters {
    display: none;
  }
}

/* ─────────────────────────────────────────────
   ANIMATIONS
   ───────────────────────────────────────────── */

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(16px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.animate-in {
  animation: fadeInUp 0.6s var(--ease) forwards;
  opacity: 0;
}

.animate-in:nth-child(1) { animation-delay: 0s; }
.animate-in:nth-child(2) { animation-delay: 0.1s; }
.animate-in:nth-child(3) { animation-delay: 0.2s; }

/* ─────────────────────────────────────────────
   ARCHITECTURE DIAGRAMS — Blueprint style
   ───────────────────────────────────────────── */

.arch-block {
  margin: 2rem 0;
  border: 1px solid #27272a;
  background: var(--bg-code);
  overflow: hidden;
}

@media (min-width: 900px) {
  .article-content .arch-block {
    margin-left: -1.5rem;
    margin-right: -1.5rem;
  }
}

.arch-block .arch-label {
  padding: 0.5rem 1rem;
  font-family: var(--font-mono);
  font-size: 0.65rem;
  font-weight: 500;
  color: #38a3ff;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  border-bottom: 1px solid rgba(255, 255, 255, 0.06);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.arch-block .arch-label::before {
  content: '◆';
  font-size: 0.45rem;
  opacity: 0.5;
}

.arch-block pre {
  margin: 0;
  border: none;
}

.arch-block pre code {
  font-size: 0.75rem;
  line-height: 1.5;
}

/* ─────────────────────────────────────────────
   GLOSSARY BLOCK
   ───────────────────────────────────────────── */

.glossary {
  margin: 2rem 0;
  border: 1px solid var(--border);
}

.glossary-header {
  padding: 0.6rem 1.25rem;
  font-family: var(--font-mono);
  font-size: 0.65rem;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--ink-muted);
  border-bottom: 1px solid var(--border);
  background: var(--surface);
}

.glossary-body {
  padding: 1.25rem;
}

.glossary-body dl {
  margin: 0;
}

.glossary-body dt {
  font-family: var(--font-display);
  font-weight: 600;
  color: var(--ink);
  font-size: 0.95rem;
  margin-top: 0.75rem;
}

.glossary-body dt:first-child {
  margin-top: 0;
}

.glossary-body dd {
  color: var(--ink-secondary);
  font-size: 0.88rem;
  line-height: 1.6;
  margin: 0.2rem 0 0 0;
  padding-left: 1rem;
  border-left: 2px solid var(--border);
}

/* ─────────────────────────────────────────────
   GUIDE CARDS — Decision matrix
   ───────────────────────────────────────────── */

.guide-grid {
  display: grid;
  gap: 0.5rem;
  margin: 2rem 0;
}

.guide-card {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 0.75rem;
  padding: 0.85rem 1.15rem;
  background: var(--bg-alt);
  border: 1px solid var(--border);
  align-items: baseline;
  transition: border-color var(--dur) var(--ease);
}

.guide-card:hover {
  border-color: var(--accent);
}

.guide-need {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 0.88rem;
  color: var(--ink);
}

.guide-answer {
  font-size: 0.88rem;
  color: var(--ink-secondary);
  line-height: 1.5;
}

.guide-answer strong {
  color: var(--accent);
}

@media (max-width: 640px) {
  .guide-card {
    grid-template-columns: 1fr;
    gap: 0.15rem;
  }
}

/* ─────────────────────────────────────────────
   WIDER ARTICLE LAYOUT
   ───────────────────────────────────────────── */

.article-content > p,
.article-content > h2,
.article-content > h3,
.article-content > h4,
.article-content > ul,
.article-content > ol,
.article-content > blockquote,
.article-content > .info-box,
.article-content > .glossary {
  max-width: 900px;
}

/* ─────────────────────────────────────────────
   MODEL ROW — Side by side text + diagram
   ───────────────────────────────────────────── */

.model-row {
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: 2rem;
  align-items: start;
  margin: 2.5rem 0;
  padding: 1.5rem 1.75rem;
  border: 1px solid var(--border);
  background: var(--bg-alt);
}

.model-row h3 {
  font-family: var(--font-display);
  font-size: 1.15rem;
  font-weight: 600;
  color: var(--ink);
  margin: 0 0 0.75rem;
  letter-spacing: -0.015em;
}

.model-row h3 .model-meta {
  font-weight: 400;
  color: var(--ink-muted);
  font-size: 0.9em;
}

.model-text p {
  font-size: 0.92rem;
  line-height: 1.7;
  color: var(--ink-secondary);
  margin-bottom: 0.75rem;
}

.model-diagram {
  position: relative;
}

.model-diagram .mermaid {
  background: var(--bg-code);
  border: 1px solid #27272a;
  padding: 1rem;
  overflow-x: auto;
}

.model-diagram .mermaid svg {
  max-width: 100%;
  height: auto;
}

/* ─────────────────────────────────────────────
   MODEL KEY — Takeaway annotation
   ───────────────────────────────────────────── */

.model-key {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--ink-muted);
  line-height: 1.6;
  padding: 0.65rem 0.85rem;
  background: var(--surface);
  border-left: 2px solid var(--accent);
  margin: 0.75rem 0;
}

.model-key strong {
  color: var(--ink);
}

.model-links {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  margin: 0.4rem 0 0.75rem;
}

.model-links a {
  color: var(--accent);
  text-decoration: none;
}

.model-links a:hover {
  text-decoration: underline;
}

.table-note {
  font-size: 0.8rem;
  color: var(--ink-muted);
  margin-top: 0.75rem;
  line-height: 1.5;
}

/* ─────────────────────────────────────────────
   AUDIO SAMPLE PLAYER
   ───────────────────────────────────────────── */

.audio-sample {
  margin: 0.75rem 0 0;
  padding: 0.6rem 0.85rem;
  background: var(--surface);
  border: 1px solid var(--border);
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.audio-sample .audio-label {
  font-family: var(--font-mono);
  font-size: 0.65rem;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--accent);
  flex-shrink: 0;
  white-space: nowrap;
}

.audio-sample audio {
  width: 100%;
  height: 32px;
}

/* ─────────────────────────────────────────────
   COMPARISON TABLE — Full-width scrollable
   ───────────────────────────────────────────── */

.full-table-wrap {
  overflow-x: auto;
  margin: 2rem 0;
  border: 1px solid var(--border);
}

.full-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.8rem;
}

.full-table th {
  background: var(--ink);
  color: var(--bg);
  padding: 0.55rem 0.7rem;
  font-family: var(--font-mono);
  font-size: 0.62rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  font-weight: 600;
  text-align: left;
  white-space: nowrap;
}

.full-table td {
  padding: 0.5rem 0.7rem;
  border-bottom: 1px solid var(--border);
  vertical-align: middle;
}

.full-table tbody tr:hover td {
  background: var(--accent-bg);
}

.full-table .era-row td {
  background: var(--surface);
  font-family: var(--font-mono);
  font-size: 0.65rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--ink-muted);
  padding: 0.4rem 0.7rem;
}

/* ─────────────────────────────────────────────
   MEL SPECTROGRAM SECTION
   ───────────────────────────────────────────── */

.mel-explain {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2rem;
  margin: 2rem 0;
  padding: 1.5rem;
  border: 1px solid var(--border);
  background: var(--bg-alt);
  align-items: center;
}

.mel-explain img {
  width: 100%;
  height: auto;
  border: 1px solid var(--border);
}

.mel-explain-text h4 {
  font-family: var(--font-display);
  font-size: 1rem;
  font-weight: 600;
  color: var(--ink);
  margin: 0 0 0.5rem;
}

.mel-explain-text p {
  font-size: 0.9rem;
  margin-bottom: 0.6rem;
  color: var(--ink-secondary);
  line-height: 1.6;
}

/* ─────────────────────────────────────────────
   TOC ADJUSTMENT — Hide for medium, show wide
   ───────────────────────────────────────────── */

@media (min-width: 1200px) and (max-width: 1499px) {
  .toc-sidebar {
    display: none;
  }
}

@media (min-width: 1500px) {
  .toc-sidebar {
    display: block;
    left: max(calc((100vw - var(--content-w)) / 2 - 230px), 1rem);
    width: 180px;
  }
}

/* ─────────────────────────────────────────────
   RESPONSIVE — Stack side-by-side on mobile
   ───────────────────────────────────────────── */

@media (max-width: 900px) {
  .model-row {
    grid-template-columns: 1fr;
  }
  .mel-explain {
    grid-template-columns: 1fr;
  }
  .article-container {
    max-width: 100%;
  }
  .article-content > p,
  .article-content > h2,
  .article-content > h3,
  .article-content > h4,
  .article-content > ul,
  .article-content > ol,
  .article-content > blockquote,
  .article-content > .info-box,
  .article-content > .glossary {
    max-width: 100%;
  }
  .full-table {
    font-size: 0.7rem;
  }
  .full-table th {
    font-size: 0.55rem;
    padding: 0.4rem 0.5rem;
  }
  .full-table td {
    padding: 0.4rem 0.5rem;
  }
}

@media (max-width: 480px) {
  .full-table {
    font-size: 0.65rem;
  }
  .full-table th,
  .full-table td {
    padding: 0.35rem 0.4rem;
  }
  .glossary-body dl {
    padding: 0.75rem;
  }
  .model-key {
    font-size: 0.7rem;
    padding: 0.5rem 0.65rem;
  }
}