/* ===== 共通リセット・ベース ===== */
* { box-sizing: border-box; margin: 0; padding: 0; }
body {
  font-family: "Hiragino Sans", "Hiragino Kaku Gothic ProN", "Noto Sans JP", Meiryo, sans-serif;
  background: #f8fafc; color: #1e293b; font-size: 14px; line-height: 1.6;
}
html { scroll-padding-top: 70px; }

/* ===== ヘッダー ===== */
.site-header {
  background: #1a4d7c; color: white; padding: 0 24px; height: 54px;
  display: flex; align-items: center; justify-content: space-between;
  position: sticky; top: 0; z-index: 100; box-shadow: 0 2px 8px rgba(0,0,0,0.2);
}
.header-inner {
  max-width: 1240px; width: 100%; margin: 0 auto;
  display: flex; align-items: center; justify-content: space-between;
}
.site-logo {
  font-family: 'Inter', 'Noto Sans JP', sans-serif;
  font-size: 21px; font-weight: 800; letter-spacing: 0.04em;
  color: white; text-decoration: none;
}
.header-nav a {
  color: #cbd5e1; text-decoration: none; margin-left: 20px; font-size: 13px;
}
.header-nav a:hover { color: white; }

/* ===== フッター ===== */
.site-footer {
  background: #1a4d7c; color: #94a3b8; text-align: center;
  padding: 22px; margin-top: 40px; font-size: 12px;
}
.footer-inner {
  max-width: 1060px; margin: 0 auto;
}
.footer-logo {
  font-size: 15px; font-weight: 700; color: white; margin-bottom: 6px;
}
.footer-desc {
  margin-bottom: 6px;
}
.footer-copy {
  font-size: 11px;
}

/* ===== コラム: ヒーローセクション ===== */
.col-body { max-width: 1060px; margin: 0 auto; padding: 0 24px; }
.col-hero {
  background: linear-gradient(135deg, #1a3a5c 0%, #2d6a9f 100%);
  color: #fff; padding: 56px 0 48px; margin-bottom: 0;
}
.col-hero-inner { max-width: 1060px; margin: 0 auto; padding: 0 24px; }
.col-hero .breadcrumb { font-size: 0.82rem; color: rgba(255,255,255,0.75); margin-bottom: 18px; }
.col-hero .breadcrumb a { color: rgba(255,255,255,0.85); text-decoration: none; }
.col-hero h1 { font-size: clamp(1.4rem, 3vw, 2rem); font-weight: 700; line-height: 1.45; margin: 0 0 20px; }
.col-meta { font-size: 0.83rem; color: rgba(255,255,255,0.75); display: flex; gap: 20px; flex-wrap: wrap; }

/* ===== コラム: 記事本文 ===== */
.col-article { padding: 48px 0 80px; }
.col-article h2 { font-size: 1.35rem; font-weight: 700; color: #1a3a5c; border-left: 4px solid #2d6a9f; padding-left: 14px; margin: 48px 0 18px; }
.col-article h3 { font-size: 1.1rem; font-weight: 700; color: #1a3a5c; margin: 32px 0 12px; }
.col-article p { line-height: 1.85; color: #333; margin: 0 0 16px; }
.col-article ul, .col-article ol { padding-left: 1.6em; margin: 0 0 16px; }
.col-article li { line-height: 1.85; color: #333; margin-bottom: 6px; }

/* ===== コラム: テーブル ===== */
.col-article table { width: 100%; border-collapse: collapse; margin: 24px 0; font-size: 0.92rem; }
.col-article th { background: #1a3a5c; color: #fff; padding: 10px 14px; text-align: left; font-weight: 600; }
.col-article td { padding: 10px 14px; border-bottom: 1px solid #e0e6ef; vertical-align: top; }
.col-article tr:nth-child(even) td { background: #f4f7fb; }

/* ===== コラム: コールアウト ===== */
.callout { background: #eef4fb; border-left: 4px solid #2d6a9f; padding: 16px 20px; margin: 24px 0; border-radius: 0 6px 6px 0; }
.callout-warn { background: #fff8e6; border-left: 4px solid #e6a817; }
.callout strong { display: block; margin-bottom: 6px; color: #1a3a5c; font-size: 0.95rem; }

/* ===== コラム: 目次 ===== */
.toc { background: #f4f7fb; border: 1px solid #d0dcea; border-radius: 8px; padding: 20px 24px; margin: 0 0 40px; }
.toc h2 { font-size: 1rem; color: #1a3a5c; border: none; padding: 0; margin: 0 0 12px; }
.toc ol { margin: 0; padding-left: 1.4em; }
.toc li { margin-bottom: 6px; }
.toc a { color: #2d6a9f; text-decoration: none; font-size: 0.92rem; }
.toc a:hover { text-decoration: underline; }

/* ===== コラム: 戻るリンク ===== */
.back-link { text-align: center; margin-top: 48px; }
.back-link a { display: inline-block; padding: 12px 32px; background: #2d6a9f; color: #fff; border-radius: 6px; text-decoration: none; font-weight: 600; font-size: 0.95rem; transition: background 0.2s; }
.back-link a:hover { background: #1a3a5c; }

/* ===== レスポンシブ ===== */
@media (max-width: 640px) {
  .col-article table { font-size: 0.82rem; }
  .col-article th, .col-article td { padding: 8px 10px; }
  .header-nav { display: none; }
}