/* =========================================================
   コラム（一覧・記事）— トップページの紺（ink）×朱（vermillion）×生成り（cream）に合わせる
   変数は chrome.css（:root）を使用。エディタ用に既定値も置く
   ========================================================= */
:root {
  --navy: #0E1B2C; --navy-light: #1A2840; --gold: #C8472B; --gold-light: #E8A08E;
  --cream: #F4EFE5; --cream-light: #FAF7F1; --text-dark: #0E1B2C; --text-body: #2A2A2A;
  --text-muted: #6B7280; --border: rgba(14, 27, 44, 0.12);
}
.bt-pc { display: inline; }
@media (max-width: 768px) { .bt-pc { display: none; } }

/* ---- ページ見出し ---- */
.bt-page-head {
  background: var(--navy); color: #fff; padding: 72px 0 64px; text-align: center;
  position: relative; overflow: hidden;
}
.bt-page-head::after {
  content: ""; position: absolute; left: 50%; bottom: 0; width: 64px; height: 2px;
  background: var(--gold); transform: translateX(-50%);
}
.bt-page-head .section-eyebrow { color: var(--gold-light); }
.bt-page-head h1 { font-size: clamp(26px, 4vw, 36px); font-weight: 600; line-height: 1.5; letter-spacing: 0.04em; }
.bt-page-head p { color: rgba(255,255,255,0.75); margin-top: 16px; font-size: 15px; }

.bt-section { padding: 48px 0 96px; background: var(--cream-light); }
.bt-section--article { background: #fff; padding-top: 32px; }
.bt-narrow { max-width: 760px; margin: 0 auto; padding: 0 24px; }

/* ---- パンくず ---- */
.bt-breadcrumb { font-size: 12px; color: var(--text-muted); margin-bottom: 28px; }
.bt-breadcrumb ol { list-style: none; display: flex; flex-wrap: wrap; gap: 4px; }
.bt-breadcrumb li + li::before { content: "›"; margin: 0 8px; color: var(--border-dark, #C9C3B5); }
.bt-breadcrumb a { color: var(--navy); text-decoration: none; }
.bt-breadcrumb a:hover { color: var(--gold); }

/* ---- カテゴリー ---- */
.bt-cats { display: flex; flex-wrap: wrap; gap: 8px; margin-bottom: 32px; }
.bt-cats a {
  font-size: 13px; padding: 6px 16px; background: #fff; border: 1px solid var(--border);
  color: var(--navy); text-decoration: none; letter-spacing: 0.05em;
}
.bt-cats a.is-current, .bt-cats a:hover { background: var(--navy); color: #fff; border-color: var(--navy); }

/* ---- カード ---- */
.bt-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(300px, 1fr)); gap: 28px; }
.bt-grid--3 { grid-template-columns: repeat(3, 1fr); gap: 20px; }
@media (max-width: 900px) { .bt-grid--3 { grid-template-columns: 1fr; } }
.bt-card {
  background: #fff; border: 1px solid var(--border); display: flex; flex-direction: column;
  text-decoration: none; color: inherit; transition: box-shadow .2s, transform .2s;
}
.bt-card:hover { box-shadow: 0 12px 32px rgba(15,30,61,0.10); transform: translateY(-2px); }
.bt-card__thumb { aspect-ratio: 16 / 9; background: var(--navy); overflow: hidden; }
.bt-card__thumb img { width: 100%; height: 100%; object-fit: cover; display: block; }
.bt-card__thumb--blank {
  display: flex; align-items: center; justify-content: center; text-align: center;
  color: var(--gold-light); font-size: 15px; line-height: 1.7; letter-spacing: 0.1em;
  background: linear-gradient(135deg, var(--navy) 0%, var(--navy-light) 100%);
}
.bt-card__body { padding: 20px 22px 24px; display: flex; flex-direction: column; gap: 10px; flex: 1; }
.bt-card__meta { display: flex; gap: 12px; align-items: center; font-size: 12px; color: var(--text-muted); }
.bt-card__cat { color: var(--gold); letter-spacing: 0.08em; font-weight: 500; }
.bt-card__title { font-size: 17px; font-weight: 600; color: var(--navy); line-height: 1.6; }
.bt-card__excerpt { font-size: 13px; color: var(--text-body); line-height: 1.8; }

.bt-pager { margin-top: 48px; display: flex; justify-content: center; gap: 6px; }
.bt-pager .page-numbers {
  min-width: 40px; height: 40px; display: inline-flex; align-items: center; justify-content: center;
  border: 1px solid var(--border); background: #fff; color: var(--navy); text-decoration: none; font-size: 14px;
}
.bt-pager .page-numbers.current, .bt-pager a.page-numbers:hover { background: var(--navy); color: #fff; border-color: var(--navy); }
.bt-empty { background: #fff; border: 1px solid var(--border); padding: 56px 24px; text-align: center; color: var(--text-muted); }

/* ---- 記事 ---- */
.bt-article__meta { display: flex; flex-wrap: wrap; gap: 14px; font-size: 12px; color: var(--text-muted); margin-bottom: 14px; }
.bt-article__meta a { color: var(--gold); text-decoration: none; letter-spacing: 0.08em; font-weight: 500; }
.bt-article__title { font-size: clamp(24px, 3.6vw, 32px); font-weight: 600; color: var(--navy); line-height: 1.55; letter-spacing: 0.02em; }
.bt-article__thumb { margin: 28px 0 0; }
.bt-article__thumb img { width: 100%; height: auto; display: block; }
.bt-article__head { padding-bottom: 28px; border-bottom: 1px solid var(--border); margin-bottom: 36px; }

.bt-prose { font-size: 16px; line-height: 2; color: var(--text-body); }
.bt-prose > * + * { margin-top: 1.4em; }
.bt-prose h2 {
  font-family: var(--font-jp-serif, 'Noto Serif JP', serif); font-size: 23px; font-weight: 600; color: var(--navy);
  line-height: 1.6; margin-top: 2.6em; padding: 0 0 12px; border-bottom: 2px solid var(--navy); position: relative;
}
.bt-prose h2::after { content: ""; position: absolute; left: 0; bottom: -2px; width: 72px; height: 2px; background: var(--gold); }
.bt-prose h3 {
  font-family: var(--font-jp-serif, 'Noto Serif JP', serif); font-size: 19px; font-weight: 600; color: var(--navy);
  margin-top: 2em; padding-left: 14px; border-left: 3px solid var(--gold); line-height: 1.6;
}
.bt-prose h4 { font-size: 16px; font-weight: 700; color: var(--navy); margin-top: 1.8em; }
.bt-prose a { color: var(--navy); text-decoration: underline; text-decoration-color: var(--gold); text-underline-offset: 3px; }
.bt-prose a:hover { color: var(--gold); }
.bt-prose strong { color: var(--text-dark); background: linear-gradient(transparent 62%, rgba(212,185,140,0.35) 62%); }
.bt-prose ul, .bt-prose ol { padding-left: 1.5em; }
.bt-prose li + li { margin-top: 0.4em; }
.bt-prose blockquote {
  background: var(--cream-light); border-left: 3px solid var(--gold); padding: 18px 22px; color: var(--text-body); font-size: 15px;
}
.bt-prose table { width: 100%; border-collapse: collapse; font-size: 14px; line-height: 1.7; }
.bt-prose th, .bt-prose td { border: 1px solid var(--border); padding: 10px 12px; text-align: left; vertical-align: top; }
.bt-prose th { background: var(--cream); color: var(--navy); font-weight: 600; }
.bt-prose figure { margin-left: 0; margin-right: 0; }
.bt-prose img { max-width: 100%; height: auto; }
.bt-prose .wp-block-table { overflow-x: auto; }
.bt-prose figcaption { font-size: 12px; color: var(--text-muted); margin-top: 6px; }

/* 目次 */
.bt-toc { background: var(--cream-light); border: 1px solid var(--border); padding: 22px 26px; margin: 2em 0; }
.bt-toc__title { font-size: 12px; letter-spacing: 0.25em; color: var(--gold); margin: 0 0 10px; }
.bt-toc ol { list-style: none; padding: 0; margin: 0; counter-reset: toc; }
.bt-toc li { margin: 0; font-size: 14px; line-height: 1.8; }
.bt-toc li.is-h2 { counter-increment: toc; }
.bt-toc li.is-h2::before { content: counter(toc, decimal-leading-zero) "  "; color: var(--gold); font-weight: 500; }
.bt-toc li.is-h3 { padding-left: 2.2em; font-size: 13px; }
.bt-toc a { color: var(--navy); text-decoration: none; }
.bt-toc a:hover { color: var(--gold); }

/* 記事末尾 CTA */
.bt-article-cta { background: var(--navy); color: #fff; padding: 36px 32px; margin-top: 56px; position: relative; }
.bt-article-cta::before { content: ""; position: absolute; top: 0; left: 0; width: 100%; height: 3px; background: var(--gold); }
.bt-article-cta__label { font-size: 12px; letter-spacing: 0.25em; color: var(--gold-light); margin: 0 0 10px; }
.bt-article-cta__title { font-size: 21px; font-weight: 600; line-height: 1.6; margin: 0 0 12px; }
.bt-article-cta__text { font-size: 14px; color: rgba(255,255,255,0.78); line-height: 1.9; margin: 0 0 22px; }
.bt-article-cta__btns { display: flex; flex-wrap: wrap; gap: 12px; }
.bt-article-cta .btn-primary, .bt-article-cta .btn-secondary { display: inline-flex; align-items: center; gap: 10px; }

.bt-related { margin-top: 72px; padding-top: 40px; border-top: 1px solid var(--border); }
.bt-related h2 { font-size: 20px; color: var(--navy); margin-bottom: 24px; }
.bt-related .bt-card__excerpt { display: none; }
.bt-related .bt-card__title { font-size: 15px; }

@media (max-width: 768px) {
  .bt-page-head { padding: 56px 0 48px; }
  .bt-prose { font-size: 15px; }
  .bt-prose h2 { font-size: 20px; }
  .bt-prose h3 { font-size: 17px; }
  .bt-article-cta { padding: 28px 20px; }
}

/* ---- 英語記事・バイリンガル見出し ---- */
.bt-page-head h1 { font-weight: 500; }
.bt-page-head .bt-slash { color: var(--gold); margin: 0 6px; font-weight: 300; }
.bt-page-head .bt-en-serif { font-style: italic; }
.bt-page-head p.bt-page-head__en { font-family: var(--font-en-sans); font-size: 13px; margin-top: 8px; color: rgba(255,255,255,0.6); }
.bt-card__thumb--blank em { color: var(--gold); font-style: italic; }
.bt-card__thumb--blank span { font-size: 22px; color: var(--cream); letter-spacing: 0; }
.is-en .bt-card__title, .is-en.bt-card .bt-card__title { font-size: 19px; font-weight: 500; }
.bt-article.is-en .bt-prose { font-family: var(--font-en-sans); line-height: 1.8; font-size: 17px; }
.bt-article.is-en .bt-prose h2, .bt-article.is-en .bt-prose h3 { font-family: var(--font-en-serif); font-weight: 500; }
.bt-article.is-en .bt-article__title { font-weight: 500; }
.bt-article-cta .btn-secondary.bt-btn-light { color: var(--cream); }
.bt-article-cta .btn-secondary.bt-btn-light:hover { color: var(--gold-light); }
.bt-article-cta__title.bt-en-serif { font-weight: 500; font-size: 23px; }
.bt-section { background: var(--cream); }
.bt-section--article { background: #fff; }
.bt-empty .bt-en { font-size: 13px; }