/* ===== Blog-specific additions ===== */

/* Post index page breadcrumb */
.blog-breadcrumb {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.78rem;
  color: var(--text-3);
  margin-bottom: 32px;
}
.blog-breadcrumb a { color: var(--text-3); }
.blog-breadcrumb a:hover { color: var(--accent); }
.blog-breadcrumb .sep { opacity: 0.4; }

/* Post count */
.blog-count {
  font-size: 0.8rem;
  color: var(--text-3);
  margin-bottom: 28px;
}

/* Post footer navigation */
.post-nav {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  margin-top: 64px;
  padding-top: 40px;
  border-top: 1px solid rgba(255,255,255,0.06);
}
.post-nav-item {
  background: var(--card);
  border: 1px solid var(--card-border);
  border-radius: var(--r);
  padding: 16px 18px;
  display: flex;
  flex-direction: column;
  gap: 4px;
  transition: all var(--t);
  color: inherit;
  box-shadow: var(--card-shadow);
}
.post-nav-item:hover {
  border-color: var(--card-border-hover);
  background: var(--card-hover);
  color: inherit;
}
.post-nav-item.next { text-align: right; }
.post-nav-label { font-size: 0.7rem; color: var(--text-3); letter-spacing: 0.08em; text-transform: uppercase; }
.post-nav-title { font-size: 0.88rem; color: var(--text); font-weight: 500; line-height: 1.4; }

/* Theorem / Definition boxes */
.theorem, .definition, .lemma, .proof {
  background: var(--card);
  border: 1px solid var(--card-border);
  border-radius: var(--r-sm);
  padding: 16px 20px;
  margin: 24px 0;
  box-shadow: var(--card-shadow);
}
.theorem { border-left: 3px solid var(--accent); }
.definition { border-left: 3px solid #60a5fa; }
.lemma { border-left: 3px solid #a78bfa; }
.proof { border-left: 3px solid var(--text-3); }

.theorem-label, .definition-label, .lemma-label, .proof-label {
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  margin-bottom: 8px;
}
.theorem-label { color: var(--accent); }
.definition-label { color: #60a5fa; }
.lemma-label { color: #a78bfa; }
.proof-label { color: var(--text-3); }

/* ── Table of Contents ───────────────────────────────────────────── */
.post-toc {
  background: var(--card);
  border: 1px solid var(--card-border);
  border-radius: var(--r);
  padding: 18px 22px;
  margin-bottom: 36px;
  box-shadow: var(--card-shadow);
}
.post-toc-title {
  font-size: 0.68rem;
  font-weight: 700;
  letter-spacing: 0.13em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 10px;
}
.post-toc ol { padding-left: 18px; color: var(--text-2); }
.post-toc li { margin-bottom: 4px; line-height: 1.5; }
.post-toc a { color: var(--text-2); font-size: 0.83rem; }
.post-toc a:hover { color: var(--accent); }
.post-toc ol ol { margin-top: 4px; padding-left: 16px; }

@media (min-width: 1360px) {
  .post-toc {
    position: fixed;
    top: calc(var(--nav-h) + 40px);
    left: calc(50% - 420px - 220px - 40px);
    width: 220px;
    max-height: calc(100vh - var(--nav-h) - 80px);
    overflow-y: auto;
    margin-bottom: 0;
    scrollbar-width: thin;
  }
}

/* ── Aside / callout boxes ───────────────────────────────────────── */
.post-aside {
  background: var(--card);
  border: 1px solid var(--card-border);
  border-left: 3px solid var(--accent);
  border-radius: 0 var(--r-sm) var(--r-sm) 0;
  padding: 16px 20px;
  margin: 24px 0;
  box-shadow: var(--card-shadow);
}
.post-aside > *:first-child { margin-top: 0 !important; }
.post-aside > *:last-child  { margin-bottom: 0 !important; }
.post-aside h3 {
  font-family: var(--font-sans);
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--text);
  margin: 0 0 10px;
}
.post-aside .post-aside { /* nested aside */
  border-left-color: var(--text-3);
  margin: 12px 0 0;
}

/* Neutral (non-accent) aside variant */
.post-aside.neutral {
  border-left-color: var(--text-3);
}

/* ── Figures and images ──────────────────────────────────────────── */
.post-figure {
  margin: 28px 0;
  text-align: center;
}
.post-figure img,
.post-content img {
  max-width: 100%;
  height: auto;
  display: block;
  margin: 32px auto;
  border-radius: var(--r-sm);
  border: 1px solid var(--card-border);
  box-shadow: var(--card-shadow);
}
.post-figure figcaption {
  font-size: 0.77rem;
  color: var(--text-3);
  margin-top: 8px;
  font-style: italic;
}

/* ── Collapsible proof ───────────────────────────────────────────── */
details.post-proof {
  background: var(--card);
  border: 1px solid var(--card-border);
  border-radius: var(--r-sm);
  padding: 10px 16px;
  margin: 12px 0;
  box-shadow: var(--card-shadow);
}
details.post-proof summary {
  cursor: pointer;
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--text-2);
  list-style: none;
  user-select: none;
  display: flex;
  align-items: center;
  gap: 6px;
}
details.post-proof summary::-webkit-details-marker { display: none; }
details.post-proof summary::before {
  content: '▶';
  font-size: 0.6rem;
  color: var(--text-3);
  transition: transform var(--t);
  display: inline-block;
}
details.post-proof[open] summary::before { transform: rotate(90deg); }
details.post-proof .proof-body { margin-top: 12px; }