:root {
  --bg: #f4f7fb;
  --surface: #ffffff;
  --surface-soft: #eef4ff;
  --text: #0d1b2a;
  --muted: #53627a;
  --line: #d4e0f2;
  --accent: #1f6feb;
  --accent-strong: #174fb6;
  --code-bg: #0f172a;
  --code-text: #e5e7eb;
  --shadow: 0 18px 40px rgba(14, 37, 79, 0.08);
}

body[data-theme='dark'] {
  --bg: #0b1220;
  --surface: #111b2f;
  --surface-soft: #15243f;
  --text: #dce8fb;
  --muted: #9bb2d8;
  --line: #2a3a5c;
  --accent: #6ea8ff;
  --accent-strong: #9ec3ff;
  --code-bg: #050915;
  --code-text: #d5ddf0;
  --shadow: 0 20px 42px rgba(1, 4, 10, 0.45);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: 'Inter', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  background: radial-gradient(circle at top right, rgba(31, 111, 235, 0.12), transparent 50%), var(--bg);
  color: var(--text);
  line-height: 1.7;
}

main {
  min-height: 60vh;
}

a {
  color: inherit;
}

img {
  max-width: 100%;
}

.container {
  width: min(1120px, 92vw);
  margin: 0 auto;
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  border: 0;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.72rem 1.2rem;
  border-radius: 999px;
  border: 1px solid transparent;
  text-decoration: none;
  font-weight: 600;
  transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease;
}

.btn:hover {
  transform: translateY(-1px);
}

.btn-primary {
  background: var(--accent);
  color: #ffffff;
  box-shadow: 0 10px 24px rgba(31, 111, 235, 0.25);
}

.btn-primary:hover {
  background: var(--accent-strong);
}

.btn-secondary {
  border-color: var(--line);
  background: var(--surface);
  color: var(--text);
}

.section {
  padding: 4.5rem 0;
}

.section h2 {
  margin: 0 0 0.8rem;
  font-size: clamp(1.5rem, 3vw, 2rem);
  line-height: 1.2;
}

.section > .container > p {
  color: var(--muted);
  max-width: 720px;
}

.eyebrow {
  margin: 0 0 0.8rem;
  color: var(--accent);
  font-size: 0.82rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 40;
  backdrop-filter: blur(14px);
  background: color-mix(in srgb, var(--bg) 78%, transparent);
  border-bottom: 1px solid var(--line);
}

.header-shell {
  padding: 0.9rem 0;
  display: grid;
  grid-template-columns: auto 1fr;
  grid-template-areas:
    'brand tools'
    'primary primary';
  align-items: center;
  gap: 0.8rem 1rem;
}

.brand-row {
  grid-area: brand;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.8rem;
}

.brand-actions {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.logo {
  font-weight: 800;
  font-size: 1.1rem;
  letter-spacing: 0.01em;
  text-decoration: none;
}

.theme-toggle {
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 0.45rem 0.75rem;
  font: inherit;
  font-size: 0.85rem;
  color: var(--muted);
  background: var(--surface);
  cursor: pointer;
}

.menu-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 5px;
  width: 38px;
  height: 38px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: var(--surface);
  cursor: pointer;
  padding: 0;
  flex-shrink: 0;
}

.menu-toggle span {
  display: block;
  width: 18px;
  height: 2px;
  background: var(--text);
  border-radius: 2px;
  transition: transform 0.25s ease, opacity 0.2s ease;
}

.menu-toggle[aria-expanded='true'] span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.menu-toggle[aria-expanded='true'] span:nth-child(2) {
  opacity: 0;
  transform: scaleX(0);
}

.menu-toggle[aria-expanded='true'] span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

.nav-drawer {
  display: contents;
}

.primary-nav {
  grid-area: primary;
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.3rem;
}

.primary-nav a,
.secondary-nav a {
  text-decoration: none;
  color: var(--muted);
  font-weight: 600;
  font-size: 0.92rem;
  padding: 0.45rem 0.65rem;
  border-radius: 8px;
}

.primary-nav a[aria-current='page'],
.primary-nav a:hover,
.secondary-nav a[aria-current='page'],
.secondary-nav a:hover {
  color: var(--text);
  background: var(--surface-soft);
}

.header-tools {
  grid-area: tools;
  justify-self: end;
  display: flex;
  align-items: center;
  gap: 0.55rem;
  flex-wrap: wrap;
}

.secondary-nav {
  display: flex;
  align-items: center;
}

.site-search {
  position: relative;
}

.site-search input {
  width: 100%;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: var(--surface);
  color: var(--text);
  font: inherit;
  padding: 0.65rem 0.8rem;
}

.site-search input:focus {
  outline: 2px solid color-mix(in srgb, var(--accent) 42%, transparent);
  border-color: var(--accent);
}

.site-search--compact input {
  width: 230px;
  padding: 0.5rem 0.7rem;
  font-size: 0.9rem;
}

.search-results {
  position: absolute;
  top: calc(100% + 0.35rem);
  left: 0;
  right: 0;
  display: none;
  max-height: 320px;
  overflow: auto;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: var(--surface);
  box-shadow: var(--shadow);
}

.search-results.is-open {
  display: block;
}

.search-results ul {
  list-style: none;
  margin: 0;
  padding: 0.45rem;
}

.search-results li + li {
  margin-top: 0.25rem;
}

.search-results a {
  display: block;
  padding: 0.5rem 0.6rem;
  border-radius: 8px;
  text-decoration: none;
}

.search-results a small {
  display: block;
  color: var(--muted);
  margin-top: 0.15rem;
}

.search-results a:hover {
  background: var(--surface-soft);
}

.hero-home {
  padding: 6rem 0 4.6rem;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.25fr 0.95fr;
  gap: 2rem;
  align-items: start;
}

.hero-title {
  margin: 0;
  font-size: clamp(2.2rem, 5vw, 3.8rem);
  line-height: 1.04;
}

.hero-tagline {
  margin: 0.9rem 0;
  color: var(--accent);
  font-weight: 700;
  font-size: 1.1rem;
}

.hero-description {
  margin: 0;
  color: var(--muted);
  max-width: 720px;
}

.hero-actions {
  margin-top: 1.6rem;
  display: flex;
  flex-wrap: wrap;
  gap: 0.7rem;
}

.hero-search {
  margin-top: 1.2rem;
}

.hero-card {
  background: linear-gradient(160deg, var(--surface), var(--surface-soft));
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 1.4rem;
  box-shadow: var(--shadow);
}

.hero-card h2 {
  margin: 0;
  font-size: 1.15rem;
}

.hero-card ul {
  margin: 1rem 0 0;
  padding-left: 1rem;
}

.hero-card li {
  color: var(--muted);
  margin-bottom: 0.5rem;
}

.card-grid {
  margin-top: 1.4rem;
  display: grid;
  gap: 1rem;
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.card-grid--three {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.card {
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 1.15rem;
  background: var(--surface);
}

.card h3 {
  margin: 0;
  font-size: 1.04rem;
}

.card p {
  margin: 0.6rem 0 0;
  color: var(--muted);
  font-size: 0.96rem;
}

.card-link {
  text-decoration: none;
}

.path-grid {
  margin-top: 1.3rem;
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 0.85rem;
}

.path-step {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 1rem;
}

.path-step .step-number {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 1.8rem;
  height: 1.8rem;
  border-radius: 999px;
  background: var(--surface-soft);
  color: var(--accent);
  font-weight: 700;
  font-size: 0.83rem;
}

.path-step h3 {
  margin: 0.75rem 0 0.4rem;
  font-size: 1rem;
}

.path-step p {
  margin: 0;
  color: var(--muted);
  font-size: 0.93rem;
}

.post-list {
  list-style: none;
  margin: 1.3rem 0 0;
  padding: 0;
  display: grid;
  gap: 0.9rem;
}

.post-list li {
  border: 1px solid var(--line);
  border-radius: 12px;
  background: var(--surface);
  padding: 1rem;
}

.post-item-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.8rem;
}

.post-track {
  border-radius: 999px;
  padding: 0.16rem 0.65rem;
  background: var(--surface-soft);
  color: var(--accent);
  font-weight: 700;
  font-size: 0.76rem;
}

.post-date {
  color: var(--muted);
  font-size: 0.85rem;
}

.post-list h3 {
  margin: 0.6rem 0 0.35rem;
  font-size: 1.04rem;
}

.post-list p {
  margin: 0;
  color: var(--muted);
}

.tag-row {
  margin-top: 1rem;
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.tag-pill {
  display: inline-flex;
  align-items: center;
  padding: 0.3rem 0.72rem;
  border: 1px solid var(--line);
  border-radius: 999px;
  text-decoration: none;
  color: var(--muted);
  background: var(--surface);
  font-size: 0.85rem;
  font-weight: 600;
}

.tag-pill:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.subscribe-card {
  margin-top: 1.2rem;
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 1rem;
  background: linear-gradient(160deg, var(--surface), var(--surface-soft));
}

.subscribe-form {
  margin-top: 0.8rem;
  display: flex;
  gap: 0.6rem;
  flex-wrap: wrap;
}

.subscribe-form input {
  min-width: 220px;
  flex: 1;
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 0.64rem 0.75rem;
  background: var(--surface);
  color: var(--text);
  font: inherit;
}

.section-header {
  margin-bottom: 0.5rem;
}

.track-hero {
  padding: 4.2rem 0 2.2rem;
}

.track-hero p {
  margin: 0.7rem 0 0;
  color: var(--muted);
  max-width: 740px;
}

.roadmap-grid {
  margin-top: 1.4rem;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1rem;
}

.roadmap-card {
  padding: 1rem;
  border-radius: 12px;
  border: 1px solid var(--line);
  background: var(--surface);
}

.roadmap-card h3 {
  margin: 0;
  font-size: 1.05rem;
}

.roadmap-card p {
  margin: 0.6rem 0 0;
  color: var(--muted);
}

.tag-sections {
  margin-top: 1.2rem;
  display: grid;
  gap: 1rem;
}

.tag-section {
  border: 1px solid var(--line);
  background: var(--surface);
  border-radius: 12px;
  padding: 1rem;
}

.tag-section h3 {
  margin: 0;
}

.site-footer {
  border-top: 1px solid var(--line);
  margin-top: 4rem;
  padding: 2.4rem 0 1.8rem;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.2fr 1fr 1fr;
  gap: 1rem;
}

.site-footer h2 {
  margin: 0;
  font-size: 1rem;
}

.site-footer p {
  margin: 0.55rem 0 0;
  color: var(--muted);
}

.site-footer ul {
  list-style: none;
  margin: 0.8rem 0 0;
  padding: 0;
}

.site-footer li + li {
  margin-top: 0.45rem;
}

.site-footer a {
  color: var(--muted);
  text-decoration: none;
}

.site-footer a:hover {
  color: var(--text);
}

.footer-meta {
  margin-top: 1.4rem;
  border-top: 1px solid var(--line);
  padding-top: 1rem;
}

.footer-meta p {
  margin: 0;
  color: var(--muted);
  font-size: 0.9rem;
}

.post-page {
  padding-bottom: 2rem;
}

.post-header {
  padding: 3.4rem 0 1.4rem;
}

.post-header h1 {
  margin: 0;
  font-size: clamp(1.9rem, 4vw, 3rem);
  line-height: 1.16;
}

.post-description {
  margin: 0.9rem 0 0;
  color: var(--muted);
  max-width: 780px;
}

.post-meta {
  margin-top: 1rem;
  display: flex;
  gap: 0.9rem;
  flex-wrap: wrap;
  color: var(--muted);
  font-size: 0.9rem;
}

.post-layout {
  display: grid;
  grid-template-columns: 250px 1fr;
  gap: 1rem;
  align-items: start;
}

.post-toc {
  position: sticky;
  top: 6.1rem;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: var(--surface);
  padding: 0.9rem;
}

.post-toc h2 {
  margin: 0;
  font-size: 0.95rem;
}

.post-toc ul {
  margin: 0.8rem 0 0;
  padding-left: 1rem;
}

.post-toc li {
  margin-bottom: 0.45rem;
}

.post-toc li.toc-sub {
  margin-left: 0.75rem;
}

.post-toc a {
  color: var(--muted);
  text-decoration: none;
  font-size: 0.9rem;
}

.post-toc a:hover {
  color: var(--accent);
}

.post-main {
  min-width: 0;
}

.post-content {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: clamp(1rem, 3vw, 1.8rem);
}

.post-content h2,
.post-content h3,
.post-content h4 {
  margin-top: 1.55rem;
  line-height: 1.3;
}

.post-content p,
.post-content ul,
.post-content ol {
  color: var(--text);
}

.post-content a {
  color: var(--accent);
}

.post-content pre,
.post-content code {
  font-family: 'JetBrains Mono', 'Fira Code', ui-monospace, SFMono-Regular, Menlo, monospace;
}

.post-content pre {
  background: var(--code-bg);
  color: var(--code-text);
  border-radius: 10px;
  overflow: auto;
  padding: 0.95rem;
}

.post-content :not(pre) > code {
  background: color-mix(in srgb, var(--surface-soft) 80%, transparent);
  padding: 0.1rem 0.35rem;
  border-radius: 6px;
  font-size: 0.92em;
}

.post-content table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.4rem 0;
  font-size: 0.95em;
  border: 1px solid var(--line);
  border-radius: 10px;
  overflow: hidden;
}

.post-content thead {
  background: var(--surface-soft);
}

.post-content th,
.post-content td {
  padding: 0.65rem 1rem;
  text-align: left;
  border-bottom: 1px solid var(--line);
  vertical-align: top;
}

.post-content th {
  font-weight: 600;
  color: var(--text);
}

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

.post-content tbody tr:hover {
  background: color-mix(in srgb, var(--accent) 6%, transparent);
}

.post-tags-inline {
  margin-top: 1rem;
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.related-section,
.post-nav-section,
.comments-section {
  padding-top: 2rem;
}

.related-section h2,
.comments-section h2 {
  margin: 0;
  font-size: 1.25rem;
}

.post-nav {
  display: flex;
  justify-content: space-between;
  gap: 0.8rem;
  flex-wrap: wrap;
}

.about-panel {
  margin-top: 1.2rem;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: var(--surface);
  padding: 1rem;
}

@media (max-width: 980px) {
  .hero-grid,
  .post-layout,
  .footer-grid,
  .roadmap-grid {
    grid-template-columns: 1fr;
  }

  .card-grid--three,
  .card-grid,
  .path-grid {
    grid-template-columns: 1fr;
  }

  .post-toc {
    position: static;
  }

  .header-shell {
    grid-template-columns: 1fr;
    grid-template-areas: 'brand';
    padding: 0.75rem 0;
  }

  .menu-toggle {
    display: flex;
  }

  .nav-drawer {
    display: none;
    flex-direction: column;
    gap: 0.75rem;
    border-top: 1px solid var(--line);
    padding: 1rem 0 0.5rem;
    margin-top: 0.5rem;
  }

  .nav-drawer.is-open {
    display: flex;
  }

  .header-tools {
    justify-self: auto;
    flex-direction: column;
    align-items: stretch;
    width: 100%;
    gap: 0.6rem;
    flex-wrap: nowrap;
  }

  .secondary-nav {
    flex-wrap: wrap;
  }

  .primary-nav {
    border-top: 1px solid var(--line);
    padding-top: 0.6rem;
  }

  .site-search--compact input {
    width: 100%;
  }
}