/* Public blog pages — layered on top of Bootstrap 5.
   Keep this file small: Bootstrap does the heavy lifting; we only add the
   editorial touches (hero band, category chips, article typography). */

.blog-body {
  background: #fafbfc;
  color: #212529;
  font-family:
    -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto,
    "Helvetica Neue", Arial, "Noto Sans", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* Push the footer to the bottom of the viewport on short pages. */
.blog-body > main,
.blog-body > article,
.blog-body > .blog-hero + section + main { flex: 1 0 auto; }
.blog-footer { flex-shrink: 0; }

.letter-spaced { letter-spacing: 0.14em; }

/* ---------- hero ---------- */
.blog-hero {
  background:
    radial-gradient(1200px 400px at 90% -10%, #dbeafe 0%, transparent 60%),
    radial-gradient(1000px 400px at -10% 20%, #fce7f3 0%, transparent 55%),
    linear-gradient(180deg, #ffffff 0%, #f6f8fb 100%);
  border-bottom: 1px solid #eef2f7;
}
.blog-hero .display-4 { letter-spacing: -0.02em; }

/* ---------- toolbar band (chips + search) ---------- */
.blog-toolbar-wrap { position: sticky; top: 56px; z-index: 5; }
.cat-chips { display: flex; flex-wrap: wrap; gap: 8px; }
.cat-chip {
  display: inline-block;
  padding: 4px 12px;
  border-radius: 999px;
  font-size: 13px;
  text-decoration: none;
  color: #495057;
  background: #f1f3f5;
  border: 1px solid transparent;
  transition: all 0.15s ease;
}
.cat-chip:hover { background: #e9ecef; color: #212529; }
.cat-chip-active {
  background: #0d6efd;
  color: #fff !important;
  border-color: #0d6efd;
}
.cat-chip-active:hover { background: #0b5ed7; }
.search-box { max-width: 320px; width: 100%; }
.search-box .input-group-text { color: #6c757d; }

/* ---------- post cards ---------- */
.post-card {
  border-radius: 12px;
  overflow: hidden;
  transition: transform 0.15s ease, box-shadow 0.15s ease;
  background: #fff;
}
.post-card:hover {
  transform: translateY(-2px);
  box-shadow: 0 12px 24px -8px rgba(15, 23, 42, 0.12) !important;
}
.card-img-wrap { background: #f1f3f5; overflow: hidden; }
.card-img-wrap img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}
.card-img-placeholder {
  display: flex;
  align-items: center;
  justify-content: center;
  color: #adb5bd;
  font-size: 2rem;
  background:
    repeating-linear-gradient(45deg, #f1f3f5 0 10px, #f8f9fa 10px 20px);
  text-decoration: none;
}
.card-img-placeholder span { display: block; }
.post-card .card-title a { transition: color 0.15s ease; }
.post-card:hover .card-title a { color: #0d6efd !important; }

/* ---------- post detail ---------- */
.post-hero {
  height: 380px;
  background-size: cover;
  background-position: center;
  background-color: #e9ecef;
  position: relative;
}
.post-hero::after {
  content: "";
  position: absolute; inset: 0;
  background: linear-gradient(180deg, rgba(15,23,42,0) 40%, rgba(15,23,42,0.35) 100%);
}
.post-hero--plain {
  height: 120px;
  background:
    radial-gradient(1000px 300px at 50% 100%, #dbeafe 0%, transparent 70%),
    #f6f8fb;
}
.post-hero--plain::after { display: none; }

@media (max-width: 767.98px) {
  .post-hero { height: 220px; }
  .post-hero--plain { height: 80px; }
}

.post-article .breadcrumb { --bs-breadcrumb-divider-color: #adb5bd; }
.post-article .breadcrumb-item + .breadcrumb-item::before { content: "›"; }
.post-title { letter-spacing: -0.02em; }

.post-body {
  font-size: 1.075rem;
  line-height: 1.75;
  color: #2d3748;
}
.post-body h1,
.post-body h2,
.post-body h3,
.post-body h4 {
  font-weight: 700;
  letter-spacing: -0.01em;
  margin-top: 2.25rem;
  margin-bottom: 1rem;
}
.post-body h2 { font-size: 1.65rem; padding-bottom: .35rem; border-bottom: 1px solid #edf0f4; }
.post-body h3 { font-size: 1.35rem; }
.post-body h4 { font-size: 1.15rem; }
.post-body p { margin: 0 0 1.1rem; }
.post-body a { color: #0d6efd; text-decoration: none; border-bottom: 1px solid rgba(13,110,253,0.25); }
.post-body a:hover { border-bottom-color: #0d6efd; }
.post-body img {
  max-width: 100%;
  height: auto;
  border-radius: 8px;
  margin: 1.25rem 0;
  box-shadow: 0 4px 14px rgba(15, 23, 42, 0.08);
}
.post-body blockquote {
  border-left: 4px solid #0d6efd;
  padding: 0.25rem 0 0.25rem 1rem;
  margin: 1.25rem 0;
  color: #495057;
  background: #f8f9fa;
  border-radius: 0 6px 6px 0;
}
.post-body ul, .post-body ol { padding-left: 1.5rem; margin: 0 0 1.1rem; }
.post-body li { margin-bottom: 0.35rem; }
.post-body pre {
  background: #0f172a;
  color: #e2e8f0;
  padding: 16px 18px;
  border-radius: 8px;
  overflow: auto;
  font-size: 0.9rem;
  line-height: 1.55;
  margin: 1.25rem 0;
}
.post-body code {
  background: #f1f3f5;
  color: #d63384;
  padding: 2px 6px;
  border-radius: 4px;
  font-size: 0.9em;
}
.post-body pre code { background: transparent; color: inherit; padding: 0; }
.post-body hr { border-top: 1px solid #edf0f4; margin: 2rem 0; }

/* ---------- footer ---------- */
.blog-footer {
  background: #ffffff;
}
.blog-footer a { color: #6c757d; }
.blog-footer a:hover { color: #212529; }