:root {
  --post-bg: #f8fafc;
  --post-card: #ffffff;
  --post-text: #0f172a;
  --post-text-soft: #64748b;
  --post-accent: #2563eb;
  --post-border: #e2e8f0;
  --post-shadow: 0 10px 30px rgba(15, 23, 42, 0.08);
  --post-chip-bg: #ffffff;
  --post-toc-hover: #eff6ff;
  --post-blockquote-bg: #f1f5f9;
  --post-blockquote-text: #1e293b;
  --post-ad-bg: #f8fafc;
  --post-related-shadow: 0 4px 12px rgba(15, 23, 42, 0.06);
  --post-radius: 16px;
}

html.dark {
  --post-bg: #020617;
  --post-card: #0f172a;
  --post-text: #e2e8f0;
  --post-text-soft: #94a3b8;
  --post-accent: #60a5fa;
  --post-border: #1e293b;
  --post-shadow: 0 10px 30px rgba(2, 6, 23, 0.45);
  --post-chip-bg: #111827;
  --post-toc-hover: #1e293b;
  --post-blockquote-bg: #111827;
  --post-blockquote-text: #cbd5e1;
  --post-ad-bg: #0b1220;
  --post-related-shadow: 0 4px 16px rgba(2, 6, 23, 0.35);
}

.post-page {
  background: var(--post-bg);
  color: var(--post-text);
  font-family: Inter, system-ui, -apple-system, Segoe UI, Roboto, sans-serif;
  min-height: 100vh;
}

.post-progress {
  position: fixed;
  top: 0;
  left: 0;
  width: 0;
  height: 4px;
  background: var(--post-accent);
  z-index: 1000;
}

.post-page__wrap {
  max-width: 1200px;
  margin: 0 auto;
  padding: 2rem 1rem 3rem;
}

.post-hero {
  max-width: 760px;
  margin: 0 auto 1.5rem;
}

.post-breadcrumb {
  display: flex;
  gap: 0.55rem;
  font-size: 0.875rem;
  color: var(--post-text-soft);
  margin-bottom: 1rem;
}

.post-breadcrumb a {
  color: inherit;
  text-decoration: none;
}

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

.post-title {
  font-size: clamp(2rem, 3.6vw, 3.1rem);
  line-height: 1.15;
  letter-spacing: -0.02em;
  margin: 0 0 0.85rem;
}

.post-subtitle {
  color: var(--post-text-soft);
  font-size: 1.05rem;
  line-height: 1.7;
  margin: 0 0 1rem;
}

.post-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem 1rem;
  color: var(--post-text-soft);
  font-size: 0.93rem;
}

.post-layout {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.25rem;
}

.post-sidebar {
  display: none;
}

.post-sidebar__card {
  position: sticky;
  top: 96px;
  background: var(--post-card);
  border-radius: var(--post-radius);
  border: 1px solid var(--post-border);
  box-shadow: var(--post-shadow);
  padding: 1rem;
}

.post-sidebar__card h2 {
  margin: 0 0 0.75rem;
  font-size: 0.95rem;
}

.post-toc {
  margin: 0;
  padding: 0;
  list-style: none;
}

.post-toc__item a {
  display: block;
  text-decoration: none;
  color: var(--post-text-soft);
  padding: 0.35rem 0.4rem;
  border-radius: 8px;
  font-size: 0.9rem;
}

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

.post-toc__item--3 a {
  padding-left: 1.2rem;
}

.post-card {
  max-width: 840px;
  margin: 0 auto;
  background: var(--post-card);
  border-radius: var(--post-radius);
  border: 1px solid var(--post-border);
  box-shadow: var(--post-shadow);
  padding: 1rem;
}

.post-featured {
  margin: 0 0 1rem;
  overflow: hidden;
  border-radius: var(--post-radius);
}

.post-featured img {
  width: 100%;
  height: auto;
  display: block;
}

.post-share {
  display: flex;
  flex-wrap: wrap;
  gap: 0.65rem;
  margin-bottom: 1.2rem;
}

.post-share a,
.post-share button {
  border: 1px solid var(--post-border);
  background: var(--post-chip-bg);
  color: var(--post-text);
  text-decoration: none;
  border-radius: 999px;
  padding: 0.55rem 0.95rem;
  font-weight: 600;
  font-size: 0.86rem;
  cursor: pointer;
}

.post-share a:hover,
.post-share button:hover {
  border-color: var(--post-accent);
  color: var(--post-accent);
}

.post-content {
  max-width: 700px;
  margin: 0 auto;
  line-height: 1.78;
  font-size: 1.06rem;
}

.post-content h1,
.post-content h2,
.post-content h3 {
  color: var(--post-text);
  line-height: 1.3;
  margin: 2rem 0 0.9rem;
}

.post-content p,
.post-content ul,
.post-content ol,
.post-content blockquote {
  margin: 0 0 1.15rem;
}

.post-content ul,
.post-content ol {
  padding-left: 1.25rem;
}

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

.post-content img {
  width: 100%;
  height: auto;
  border-radius: 12px;
  margin: 1.2rem 0;
}

.post-content blockquote {
  border-left: 4px solid var(--post-accent);
  background: var(--post-blockquote-bg);
  padding: 0.9rem 1rem;
  border-radius: 8px;
  color: var(--post-blockquote-text);
}

.post-ad-slot {
  max-width: 700px;
  margin: 1.6rem auto;
  border: 1px solid var(--post-border);
  border-radius: 12px;
  background: var(--post-ad-bg);
  text-align: center;
  padding: 0.9rem;
}

.post-ad-slot p {
  margin: 0 0 0.45rem;
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--post-text-soft);
}

.post-related {
  max-width: 840px;
  margin: 1.8rem auto 0;
}

.post-related h2 {
  margin: 0 0 1rem;
  font-size: 1.45rem;
}

.post-related__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1rem;
}

.post-related__item {
  background: var(--post-card);
  border: 1px solid var(--post-border);
  border-radius: 12px;
  box-shadow: var(--post-related-shadow);
  overflow: hidden;
  text-decoration: none;
  color: var(--post-text);
}

.post-related__item img {
  width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: cover;
}

.post-related__item span {
  display: block;
  padding: 0.75rem 0.85rem;
  font-weight: 600;
  line-height: 1.45;
}

.post-footer {
  max-width: 840px;
  margin: 2rem auto 0;
  padding: 0 1rem 2rem;
  color: var(--post-text-soft);
  text-align: center;
}

.post-footer p {
  margin: 0 0 0.65rem;
}

.post-footer a {
  color: var(--post-accent);
  font-weight: 600;
  text-decoration: none;
}

@media (min-width: 992px) {
  .post-page__wrap {
    padding-top: 2.25rem;
  }

  .post-layout {
    grid-template-columns: 260px minmax(0, 1fr);
    align-items: start;
    gap: 1.4rem;
  }

  .post-sidebar {
    display: block;
  }

  .post-card {
    padding: 1.35rem;
  }
}

@media (min-width: 720px) {
  .post-card {
    padding: 1.3rem;
  }

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