/* =========================================================================
   KNOWLEDGE BASE - hub (/knowledge-base) and generic article (/knowledge-base/{slug})
   ========================================================================= */

.kb-page { background: var(--bg); padding: 36px 0 64px; }
.kb-shell { max-width: var(--qdt-shell); }

.kb-breadcrumb { color: var(--muted); font-size: 12.5px; margin-bottom: 20px; }
.kb-breadcrumb a { color: var(--muted); text-decoration: none; }
.kb-breadcrumb a:hover { color: var(--primary); }
.kb-breadcrumb span:not(:last-child) { margin: 0 6px; }
.kb-breadcrumb span:last-child { color: var(--text); font-weight: 600; }

.kb-hero { margin-bottom: 28px; max-width: 720px; }
.kb-eyebrow {
  align-items: center; background: var(--accent-tint); border: 1px solid var(--accent-line); border-radius: 999px;
  color: var(--accent-dark); display: inline-flex; font: 700 12px var(--font-display); margin-bottom: 14px; padding: 7px 14px;
}
.kb-hero h1 {
  color: var(--text); font-family: var(--font-display); font-size: clamp(26px, 3vw, 36px); font-weight: 800;
  letter-spacing: -0.8px; line-height: 1.15; margin: 0 0 10px;
}
.kb-hero p { color: var(--muted); font-size: 14.5px; line-height: 1.7; margin: 0; }

.kb-layout { display: grid; gap: 28px; grid-template-columns: 260px minmax(0, 1fr); align-items: start; }

/* ---------- Sidebar / nested topic nav ---------- */
.kb-sidebar {
  background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius);
  box-shadow: var(--qdt-shadow); padding: 18px; position: sticky; top: 20px;
}
.kb-sidebar-heading { color: var(--muted); font: 700 11px var(--font-mono); letter-spacing: 0.08em; margin-bottom: 10px; text-transform: uppercase; }
.kb-empty { color: var(--faint); font-size: 12.5px; }

.kb-nav-list { display: flex; flex-direction: column; gap: 4px; list-style: none; margin: 0; padding: 0; }
.kb-nav-list .kb-nav-list { margin: 4px 0 8px 14px; padding-left: 10px; border-left: 2px solid var(--line-soft); }
.kb-nav-item { display: block; }
.kb-nav-node { align-items: center; display: flex; gap: 7px; padding: 5px 0; }
.kb-nav-icon { font-size: 14px; }
.kb-nav-name {
  border-left: 3px solid var(--kb-color, var(--accent)); color: var(--text); font: 700 13px var(--font-display);
  padding-left: 8px; text-decoration: none;
}
.kb-nav-name:hover { color: var(--kb-color, var(--accent)); }

.kb-nav-articles { list-style: none; margin: 2px 0 4px 20px; padding: 0; }
.kb-nav-article { font-size: 12.5px; padding: 3px 0; }
.kb-nav-article a { color: var(--muted); text-decoration: none; }
.kb-nav-article a:hover { color: var(--accent); text-decoration: underline; }
.kb-nav-article.is-soon span { color: var(--faint); }
.kb-soon-badge {
  background: var(--surface-soft); border-radius: 5px; color: var(--faint); font: 700 9px var(--font-mono);
  margin-left: 5px; padding: 1px 5px; text-transform: uppercase;
}

/* ---------- Main content ---------- */
.kb-main { min-width: 0; }
.kb-section { margin-bottom: 32px; }
.kb-section h2 { color: var(--text); font-family: var(--font-display); font-size: 19px; font-weight: 800; margin: 0 0 14px; }

.kb-article-grid { display: grid; gap: 14px; grid-template-columns: repeat(auto-fill, minmax(260px, 1fr)); }
.kb-article-card {
  background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); color: var(--text);
  display: flex; flex-direction: column; gap: 6px; padding: 18px; text-decoration: none;
  transition: border-color .18s ease, transform .18s ease, box-shadow .18s ease;
}
.kb-article-card:hover { border-color: var(--accent-line); box-shadow: var(--qdt-shadow-lg); transform: translateY(-3px); }
.kb-article-topic {
  color: var(--accent-dark); font: 700 10px var(--font-mono); letter-spacing: 0.06em; text-transform: uppercase;
}
.kb-article-card h3 { font-family: var(--font-display); font-size: 15.5px; margin: 0; }
.kb-article-card p { color: var(--muted); font-size: 12.5px; line-height: 1.6; margin: 0; }
.kb-article-arrow { color: var(--primary); font: 700 11.5px var(--font-mono); margin-top: auto; }

.kb-topic-grid { display: grid; gap: 16px; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); }
.kb-topic-card {
  background: var(--surface); border: 1px solid var(--line); border-left: 4px solid var(--kb-color, var(--accent));
  border-radius: var(--radius); padding: 18px;
}
.kb-topic-card-head { align-items: center; display: flex; gap: 9px; margin-bottom: 10px; }
.kb-topic-icon { font-size: 19px; }
.kb-topic-card-head h3 { color: var(--text); font-family: var(--font-display); font-size: 15.5px; font-weight: 800; margin: 0; }
.kb-topic-article-list { list-style: none; margin: 0; padding: 0; }
.kb-topic-article-list li { border-top: 1px solid var(--line-soft); font-size: 13px; padding: 7px 0; }
.kb-topic-article-list li:first-child { border-top: none; }
.kb-topic-article-list a { color: var(--text); text-decoration: none; }
.kb-topic-article-list a:hover { color: var(--kb-color, var(--accent)); }
.kb-topic-article-list li.is-soon span { color: var(--faint); }
.kb-topic-subgroup { margin-top: 12px; }
.kb-topic-subgroup-name { color: var(--muted); font: 700 11px var(--font-display); margin-bottom: 4px; }

/* ---------- Article page ---------- */
.kb-article { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); box-shadow: var(--qdt-shadow); padding: 32px clamp(20px, 4vw, 44px); }
.kb-article-header { border-bottom: 1px solid var(--line-soft); margin-bottom: 22px; padding-bottom: 20px; }
.kb-article-header .kb-article-topic { display: inline-block; margin-bottom: 10px; }
.kb-article-header h1 { color: var(--text); font-family: var(--font-display); font-size: clamp(24px, 3vw, 32px); font-weight: 800; letter-spacing: -0.6px; line-height: 1.18; margin: 0 0 10px; }
.kb-article-summary { color: var(--muted); font-size: 15px; line-height: 1.7; margin: 0; }
.kb-article-image { border-radius: 10px; margin-bottom: 22px; max-width: 100%; }

.kb-article-body { color: var(--text); font-size: 15px; line-height: 1.8; }
.kb-article-body h2 { font-family: var(--font-display); font-size: 21px; font-weight: 800; margin: 30px 0 12px; }
.kb-article-body h3 { font-family: var(--font-display); font-size: 17px; font-weight: 700; margin: 24px 0 10px; }
.kb-article-body p { margin: 0 0 14px; }
.kb-article-body ul, .kb-article-body ol { margin: 0 0 14px; padding-left: 22px; }
.kb-article-body li { margin-bottom: 6px; }
.kb-article-body code { background: var(--surface-soft); border-radius: 4px; font: 12.5px var(--font-mono); padding: 2px 6px; }
.kb-article-body pre { background: var(--surface-soft); border: 1px solid var(--line); border-radius: 8px; overflow: auto; padding: 14px; }
.kb-article-body pre code { background: none; padding: 0; }
.kb-article-body a { color: var(--accent); }
.kb-article-empty { color: var(--faint); font-style: italic; }

.kb-faq { border-top: 1px solid var(--line-soft); margin-top: 30px; padding-top: 24px; }
.kb-faq h2 { color: var(--text); font-family: var(--font-display); font-size: 19px; font-weight: 800; margin: 0 0 14px; }
.kb-faq-item { background: var(--surface-soft); border: 1px solid var(--line-soft); border-radius: 9px; margin-bottom: 8px; padding: 12px 16px; }
.kb-faq-item summary { color: var(--text); cursor: pointer; font: 600 13.5px var(--font-display); }
.kb-faq-item p { color: var(--muted); font-size: 13.5px; line-height: 1.7; margin: 10px 0 0; }

@media (max-width: 880px) {
  .kb-layout { grid-template-columns: 1fr; }
  .kb-sidebar { position: static; }
}