/* Topic hub pages (Cody, 21 Oct 2026): the blog index's white, hairline look (blog-v2.css) plus the overview prose,
   the rail, the guide and course cards and the FAQ. Built by scripts/build_topic_hubs.py. */
.th-crumbs { display: flex; flex-wrap: wrap; align-items: center; gap: .4rem .6rem; font-size: .8rem; color: var(--mute); margin: 0 0 1.2rem; }
.th-crumbs a { color: inherit; text-decoration: none; }
.th-crumbs a:hover { color: var(--ink); }
.th-head { grid-template-columns: 1fr; }
.th-head .bv2-sub { max-width: 46rem; }
.th-byline { display: flex; align-items: center; gap: .7rem; margin-top: 1.1rem; font-size: .85rem; color: var(--ink-2); }
.th-byline img { width: 40px; height: 40px; border-radius: 50%; object-fit: cover; }
.th-byline strong { display: block; color: var(--ink); }
.th-overview { display: grid; grid-template-columns: minmax(0, 44rem) 18rem; gap: 3rem; justify-content: space-between; margin-top: 2.5rem; padding-top: 2.5rem; border-top: 1px solid var(--line); }
.th-prose { font-size: 1.05rem; line-height: 1.7; color: var(--ink); }
.th-prose .th-overview__title { font-family: var(--font-body, sans-serif); font-weight: 700; font-size: 1.9rem; line-height: 1.15; letter-spacing: -.015em; margin: 0 0 1rem; text-transform: none; color: var(--ink); }
.th-prose h2 { font-family: var(--font-body, sans-serif); font-size: 1.15rem; font-weight: 600; line-height: 1.3; margin: 1.8rem 0 .5rem; letter-spacing: 0; text-transform: none; color: var(--ink); }
.th-prose p { margin: 0 0 1rem; }
.th-rail { position: sticky; top: 5.5rem; align-self: start; display: flex; flex-direction: column; gap: 1.25rem; }
.th-card { border: 1px solid var(--line); border-radius: 12px; padding: 1rem 1.1rem; background: #fff; }
.th-card h4 { font-family: var(--font-body, sans-serif); font-size: .72rem; font-weight: 600; letter-spacing: .12em; text-transform: uppercase; color: var(--mute); margin: 0 0 .7rem; }
.th-card ol { list-style: none; margin: 0; padding: 0; display: flex; flex-direction: column; gap: .15rem; }
.th-card ol a { display: block; padding: .3rem 0 .3rem .7rem; border-left: 2px solid transparent; color: var(--ink-2); font-size: .86rem; line-height: 1.35; text-decoration: none; }
.th-card ol a:hover { color: var(--ink); border-left-color: var(--ink); }
.th-offer { display: grid; grid-template-columns: 72px 1fr; gap: 1rem; align-items: start; border: 1px solid var(--line); border-radius: 12px; padding: 1.1rem; background: #fff; }
.th-offer img { width: 72px; height: 72px; object-fit: cover; border-radius: 8px; background: var(--soft); }
.th-offer--guide img { object-fit: contain; background: var(--soft); }
.th-offer .bv2-kicker { margin: 0 0 .3rem; }
.th-offer h3 { font-family: var(--font-body, sans-serif); font-size: 1.02rem; font-weight: 600; line-height: 1.3; margin: 0 0 .4rem; }
.th-offer p { font-size: .88rem; line-height: 1.5; color: var(--ink-2); margin: 0 0 .9rem; }
.th-rail .th-offer { grid-template-columns: 1fr; }
.th-rail .th-offer img { width: 100%; height: auto; aspect-ratio: 16 / 9; }
.th-rail .th-offer .bv2-btn { width: 100%; }
.th-btn--ghost { background: transparent; color: var(--ink) !important; border: 1px solid var(--line); }
.th-btn--ghost:hover { background: var(--soft); }
.th-offers { display: grid; grid-template-columns: repeat(2, 1fr); gap: 1.25rem; margin-top: 2.5rem; }
.th-faq { margin-top: 3rem; max-width: 44rem; }
.th-faq h2, .th-others h2 { font-family: var(--font-body, sans-serif); font-size: .72rem; font-weight: 600; letter-spacing: .12em; text-transform: uppercase; color: var(--mute); margin: 0 0 1rem; }
.th-faq .faq-item { border-top: 1px solid var(--line); }
.th-faq .faq-item:last-child { border-bottom: 1px solid var(--line); }
.th-faq .faq-question { display: flex; justify-content: space-between; align-items: center; gap: 1rem; padding: .95rem 0; cursor: pointer; font-weight: 600; font-size: 1rem; line-height: 1.4; color: var(--ink); }
.th-faq .faq-question::after { content: "+"; font-size: 1.3rem; line-height: 1; color: var(--mute); flex: 0 0 auto; }
.th-faq .faq-item.open .faq-question::after { content: "–"; }
.th-faq .faq-answer { display: none; padding: 0 0 1rem; font-size: .98rem; line-height: 1.6; color: var(--ink-2); }
.th-faq .faq-item.open .faq-answer { display: block; }
.th-others { margin-top: 3rem; }
.th-others ul { list-style: none; margin: 0; padding: 0; display: grid; grid-template-columns: repeat(3, 1fr); gap: 1.25rem; }
.th-others a { display: block; height: 100%; border: 1px solid var(--line); border-radius: 12px; padding: 1rem 1.1rem; text-decoration: none; color: inherit; transition: border-color .15s; }
.th-others a:hover { border-color: var(--ink); }
.th-others h3 { font-family: var(--font-body, sans-serif); font-size: 1.02rem; font-weight: 600; line-height: 1.3; margin: .3rem 0 .4rem; }
.th-others p { margin: 0; font-size: .88rem; line-height: 1.5; color: var(--ink-2); display: -webkit-box; -webkit-line-clamp: 3; -webkit-box-orient: vertical; overflow: hidden; }
.th-author { display: grid; grid-template-columns: 72px 1fr; gap: 1.1rem; align-items: start; margin-top: 3rem; padding-top: 2rem; border-top: 1px solid var(--line); }
.th-author img { width: 72px; height: 72px; border-radius: 50%; object-fit: cover; }
.th-author h3 { font-family: var(--font-body, sans-serif); font-size: 1.05rem; font-weight: 600; margin: 0 0 .2rem; }
.th-author .th-role { font-size: .82rem; color: var(--mute); margin: 0 0 .6rem; }
.th-author p { font-size: .95rem; line-height: 1.55; color: var(--ink-2); margin: 0 0 .5rem; }
@media (max-width: 991px) {
  .th-overview { grid-template-columns: 1fr; }
  .th-rail { position: static; }
  .th-rail .th-offer { grid-template-columns: 72px 1fr; }
  .th-rail .th-offer img { width: 72px; height: 72px; aspect-ratio: auto; }
  .th-rail .th-offer .bv2-btn { width: auto; }
  .th-others ul { grid-template-columns: 1fr; }
}
@media (max-width: 700px) {
  .th-offers { grid-template-columns: 1fr; }
  .th-offer, .th-rail .th-offer { grid-template-columns: 1fr; }
  .th-offer img, .th-rail .th-offer img { width: 100%; height: auto; aspect-ratio: 16 / 9; }
  .th-author { grid-template-columns: 1fr; }
}