/* ==========================================================================
   SCR Lab Wiki — main.css
   仕様: SCR-WIKI-SPEC-001 §7
   ========================================================================== */

/* --------------------------------------------------------------------------
   1. CSS 変数 / カラーパレット (7.2)
   -------------------------------------------------------------------------- */

:root,
[data-theme="light"] {
  --bg:              #FAFAFA;
  --bg-sidebar:      #F3F4F6;
  --bg-card:         #FFFFFF;
  --text-primary:    #1A1A2E;
  --text-secondary:  #4A4A6A;
  --text-muted:      #8A8AA0;
  --accent:          #2D5BE3;
  --accent-hover:    #1A3FB0;
  --border:          #E2E4EA;
  --code-bg:         #EEF0F5;
  --warning-bg:      #FFF8E1;
  --warning-border:  #F9A825;
  --info-bg:         #E3F0FF;
  --info-border:     #2D5BE3;
  --danger-bg:       #FFF0F0;
  --danger-border:   #E53935;
  --tip-bg:          #F0FFF4;
  --tip-border:      #2E7D32;

  /* レイアウト */
  --sidebar-width:   240px;
  --toc-width:       200px;
  --content-max:     780px;
  --header-height:   60px;

  /* タイポグラフィ */
  --font-sans:   'Noto Sans JP', system-ui, sans-serif;
  --font-serif:  'Noto Serif JP', Georgia, serif;
  --font-mono:   'JetBrains Mono', 'Fira Code', Consolas, monospace;
  --font-latin:  'Inter', system-ui, sans-serif;

  /* シャドウ */
  --shadow-sm:  0 1px 3px rgba(0,0,0,.06), 0 1px 2px rgba(0,0,0,.04);
  --shadow-md:  0 4px 12px rgba(0,0,0,.08);
  --shadow-lg:  0 8px 24px rgba(0,0,0,.12);

  /* トランジション */
  --transition: 0.2s ease;
}

[data-theme="dark"] {
  --bg:              #0F1117;
  --bg-sidebar:      #161B26;
  --bg-card:         #1C2233;
  --text-primary:    #E8EAF0;
  --text-secondary:  #A0A8C0;
  --text-muted:      #606880;
  --accent:          #6B9BF8;
  --accent-hover:    #8FB3FF;
  --border:          #2A3048;
  --code-bg:         #1C2233;
  --warning-bg:      #2A220A;
  --warning-border:  #C9891A;
  --info-bg:         #0A1A30;
  --info-border:     #6B9BF8;
  --danger-bg:       #2A0A0A;
  --danger-border:   #EF5350;
  --tip-bg:          #0A1F0F;
  --tip-border:      #66BB6A;

  --shadow-sm:  0 1px 3px rgba(0,0,0,.3);
  --shadow-md:  0 4px 12px rgba(0,0,0,.4);
  --shadow-lg:  0 8px 24px rgba(0,0,0,.5);
}

/* Giallo (Zola 0.22.x) が要求する必須スタイル */
.giallo-l  { display: inline-block; min-height: 1lh; width: 100%; }
.giallo-ln {
  display: inline-block;
  user-select: none;
  margin-right: 0.4em;
  padding: 0.4em;
  min-width: 3ch;
  text-align: right;
  opacity: 0.8;
}

/* --------------------------------------------------------------------------
   2. リセット / ベース
   -------------------------------------------------------------------------- */

*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  background-color: var(--bg);
  color: var(--text-primary);
  font-family: var(--font-sans);
  font-size: 1rem;
  line-height: 1.8;
  letter-spacing: 0.02em;
  transition: background-color var(--transition), color var(--transition);
}

/* スクリーンリーダー専用 (NF-A01) */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0,0,0,0);
  white-space: nowrap;
  border: 0;
}

/* --------------------------------------------------------------------------
   3. レイアウト (7.4)
   -------------------------------------------------------------------------- */

.layout {
  display: grid;
  grid-template-columns: var(--sidebar-width) 1fr var(--toc-width);
  min-height: calc(100vh - var(--header-height));
  max-width: 1440px;
  margin: 0 auto;
}

/* --------------------------------------------------------------------------
   4. ヘッダ (7.4)
   -------------------------------------------------------------------------- */

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  height: var(--header-height);
  background-color: var(--bg-card);
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0 1.25rem;
  box-shadow: var(--shadow-sm);
  transition: background-color var(--transition);
}

.site-header__logo {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  text-decoration: none;
  color: var(--text-primary);
  font-family: var(--font-latin);
  font-size: 1rem;
  white-space: nowrap;
  flex-shrink: 0;
}
.site-header__logo:hover { color: var(--accent); }
.site-header__logo-mark {
  font-size: 1.2rem;
  color: var(--accent);
}
.site-header__logo-text strong { font-weight: 700; }

.site-header__actions {
  display: flex;
  align-items: center;
  gap: 0.25rem;
  margin-left: auto;
  flex-shrink: 0;
}

/* ハンバーガー（デスクトップでは非表示） */
.hamburger {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 36px;
  height: 36px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 6px;
  border-radius: 6px;
  flex-shrink: 0;
}
.hamburger:hover { background: var(--code-bg); }
.hamburger__bar {
  display: block;
  width: 20px;
  height: 2px;
  background: var(--text-primary);
  border-radius: 2px;
  transition: var(--transition);
}

/* アイコンボタン共通 */
.icon-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  background: none;
  border: none;
  border-radius: 6px;
  cursor: pointer;
  color: var(--text-secondary);
  text-decoration: none;
  transition: background var(--transition), color var(--transition);
}
.icon-btn:hover { background: var(--code-bg); color: var(--accent); }

/* テーマボタン: sun/moon 切替 */
[data-theme="light"] .icon--moon { display: none; }
[data-theme="dark"]  .icon--sun  { display: none; }

/* --------------------------------------------------------------------------
   5. 検索 (F-B02)
   -------------------------------------------------------------------------- */

.search-wrapper {
  position: relative;
  flex: 1;
  max-width: 480px;
  margin: 0 0.5rem;
}

.search-box {
  position: relative;
  display: flex;
  align-items: center;
}
.search-box__icon {
  position: absolute;
  left: 10px;
  color: var(--text-muted);
  pointer-events: none;
}
.search-box__input {
  width: 100%;
  height: 36px;
  padding: 0 2.25rem 0 2.25rem;
  background: var(--code-bg);
  border: 1px solid var(--border);
  border-radius: 8px;
  font-family: var(--font-sans);
  font-size: 0.875rem;
  color: var(--text-primary);
  outline: none;
  transition: border-color var(--transition), box-shadow var(--transition);
}
.search-box__input::placeholder { color: var(--text-muted); }
.search-box__input:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px color-mix(in srgb, var(--accent) 15%, transparent);
  background: var(--bg-card);
}
.search-box__kbd {
  position: absolute;
  right: 8px;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--text-muted);
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 0 5px;
  pointer-events: none;
}
.search-box__input:focus + .search-box__kbd { display: none; }

/* 検索結果 */
.search-results {
  position: absolute;
  top: calc(100% + 6px);
  left: 0;
  right: 0;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 10px;
  box-shadow: var(--shadow-lg);
  z-index: 200;
  overflow: hidden;
  max-height: 480px;
  overflow-y: auto;
}
.search-result-item {
  display: block;
  padding: 0.75rem 1rem;
  text-decoration: none;
  border-bottom: 1px solid var(--border);
  transition: background var(--transition);
}
.search-result-item:last-child { border-bottom: none; }
.search-result-item:hover,
.search-result-item.is-focused { background: var(--code-bg); }
.search-result-item__title {
  font-weight: 600;
  font-size: 0.9rem;
  color: var(--text-primary);
  display: block;
}
.search-result-item__meta {
  font-size: 0.8rem;
  color: var(--text-muted);
  margin-top: 2px;
}
.search-result-item__snippet {
  font-size: 0.8rem;
  color: var(--text-secondary);
  margin-top: 4px;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}
.search-no-results {
  padding: 1rem;
  text-align: center;
  color: var(--text-muted);
  font-size: 0.875rem;
}

/* --------------------------------------------------------------------------
   6. サイドバー (F-B01 / 7.4)
   -------------------------------------------------------------------------- */

.sidebar {
  width: var(--sidebar-width);
  border-right: 1px solid var(--border);
  background: var(--bg-sidebar);
  transition: background-color var(--transition);
  overflow: hidden;
}
.sidebar__inner {
  position: sticky;
  top: var(--header-height);
  height: calc(100vh - var(--header-height));
  overflow-y: auto;
  padding: 1rem 0;
  scrollbar-width: thin;
  scrollbar-color: var(--border) transparent;
}

/* カテゴリボタン */
.sidebar__cat-btn {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  width: 100%;
  padding: 0.5rem 1rem;
  background: none;
  border: none;
  cursor: pointer;
  font-family: var(--font-sans);
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--text-secondary);
  transition: color var(--transition), background var(--transition);
}
.sidebar__cat-btn:hover { color: var(--accent); background: color-mix(in srgb, var(--accent) 5%, transparent); }
.sidebar__cat-icon { font-size: 1rem; }
.sidebar__cat-name { flex: 1; text-align: left; }
.sidebar__chevron {
  transition: transform var(--transition);
  flex-shrink: 0;
}
.sidebar__cat-btn[aria-expanded="true"] .sidebar__chevron {
  transform: rotate(180deg);
}

/* ページリスト */
.sidebar__pages {
  list-style: none;
  overflow: hidden;
  max-height: 0;
  transition: max-height 0.25s ease;
}
.sidebar__pages.is-open { max-height: 2000px; }

.sidebar__page-item { list-style: none; }
.sidebar__page-link {
  display: block;
  padding: 0.35rem 1rem 0.35rem 2.25rem;
  font-size: 0.875rem;
  color: var(--text-secondary);
  text-decoration: none;
  border-left: 2px solid transparent;
  transition: color var(--transition), border-color var(--transition), background var(--transition);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.sidebar__page-link:hover { color: var(--accent); background: color-mix(in srgb, var(--accent) 5%, transparent); }
.sidebar__page-link.is-active {
  color: var(--accent);
  border-left-color: var(--accent);
  background: color-mix(in srgb, var(--accent) 8%, transparent);
  font-weight: 600;
}
.sidebar__empty {
  padding: 0.35rem 1rem 0.35rem 2.25rem;
  font-size: 0.8rem;
  color: var(--text-muted);
  font-style: italic;
}

/* --------------------------------------------------------------------------
   7. メインコンテンツ (7.4)
   -------------------------------------------------------------------------- */

.main-content {
  min-width: 0;
  padding: 2rem 2.5rem;
}

/* --------------------------------------------------------------------------
   8. ToC (F-A04 / 7.4)
   -------------------------------------------------------------------------- */

.toc {
  width: var(--toc-width);
  padding: 1.5rem 1rem;
  border-left: 1px solid var(--border);
}
.toc__inner {
  position: sticky;
  top: calc(var(--header-height) + 1.5rem);
  max-height: calc(100vh - var(--header-height) - 3rem);
  overflow-y: auto;
}
.toc__heading {
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-bottom: 0.75rem;
}
.toc__list, .toc__sublist { list-style: none; }
.toc__sublist { padding-left: 0.75rem; }
.toc__sublist--deep { padding-left: 0.5rem; }
.toc__link {
  display: block;
  padding: 0.2rem 0;
  font-size: 0.8rem;
  color: var(--text-secondary);
  text-decoration: none;
  line-height: 1.4;
  transition: color var(--transition);
}
.toc__link:hover { color: var(--accent); }
.toc__link--sub { font-size: 0.775rem; color: var(--text-muted); }
.toc__link--deep { font-size: 0.75rem; color: var(--text-muted); }

/* --------------------------------------------------------------------------
   9. ページ記事 (7.3 / 7.5)
   -------------------------------------------------------------------------- */

.page-article__header { margin-bottom: 2rem; }
.page-article__meta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin-bottom: 0.75rem;
}
.page-article__title {
  font-family: var(--font-serif);
  font-size: 1.8rem;
  line-height: 1.4;
  color: var(--text-primary);
  margin-bottom: 0.5rem;
}
.page-article__description {
  font-size: 1.05rem;
  color: var(--text-secondary);
  margin-bottom: 0.75rem;
}
.page-article__info {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  font-size: 0.85rem;
  color: var(--text-muted);
  border-top: 1px solid var(--border);
  padding-top: 0.75rem;
}
.page-article__authors,
.page-article__dates {
  display: flex;
  align-items: center;
  gap: 0.35rem;
}

/* --------------------------------------------------------------------------
   10. Prose (本文スタイル)
   -------------------------------------------------------------------------- */

.prose {
  max-width: var(--content-max);
  color: var(--text-primary);
}
.prose h1 { font-family: var(--font-serif); font-size: 1.8rem; line-height: 1.4; margin: 2.5rem 0 1rem; }
.prose h2 { font-family: var(--font-serif); font-size: 1.4rem; line-height: 1.4; margin: 2rem 0 0.75rem; padding-bottom: 0.4rem; border-bottom: 1px solid var(--border); }
.prose h3 { font-family: var(--font-sans); font-size: 1.15rem; font-weight: 700; margin: 1.5rem 0 0.5rem; }
.prose h4 { font-family: var(--font-sans); font-size: 1rem; font-weight: 700; margin: 1.25rem 0 0.4rem; }
.prose p  { margin-bottom: 1rem; }
.prose ul, .prose ol { margin: 0.5rem 0 1rem 1.5rem; }
.prose li { margin-bottom: 0.25rem; }
.prose blockquote {
  border-left: 4px solid var(--accent);
  padding: 0.5rem 1rem;
  margin: 1rem 0;
  color: var(--text-secondary);
  background: var(--code-bg);
  border-radius: 0 6px 6px 0;
}
.prose hr { border: none; border-top: 1px solid var(--border); margin: 2rem 0; }
.prose table { width: 100%; border-collapse: collapse; margin: 1rem 0; font-size: 0.9rem; }
.prose th { background: var(--code-bg); font-weight: 700; text-align: left; padding: 0.5rem 0.75rem; border: 1px solid var(--border); }
.prose td { padding: 0.5rem 0.75rem; border: 1px solid var(--border); }
.prose tr:nth-child(even) td { background: color-mix(in srgb, var(--bg-card) 60%, var(--code-bg)); }
.prose img { max-width: 100%; border-radius: 8px; margin: 1rem 0; box-shadow: var(--shadow-sm); }

/* インラインコード */
.prose code:not(pre code) {
  background: var(--code-bg);
  color: var(--accent);
  font-family: var(--font-mono);
  font-size: 0.875em;
  padding: 0.1em 0.4em;
  border-radius: 4px;
}

/* コードブロック (7.5) */
.prose pre {
  background: var(--code-bg);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 1rem 1.25rem;
  overflow-x: auto;
  margin: 1rem 0;
  font-family: var(--font-mono);
  font-size: 0.875rem;
  line-height: 1.6;
  position: relative;
}
.prose pre code { background: none; color: inherit; padding: 0; font-size: inherit; }

/* コードブロック: コピーボタン */
.code-block-wrapper {
  position: relative;
}
.code-copy-btn {
  position: absolute;
  top: 8px;
  right: 8px;
  display: none;
  padding: 4px 8px;
  font-size: 0.75rem;
  font-family: var(--font-sans);
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 4px;
  cursor: pointer;
  color: var(--text-secondary);
  transition: var(--transition);
}
.code-block-wrapper:hover .code-copy-btn { display: block; }
.code-copy-btn:hover { color: var(--accent); border-color: var(--accent); }

/* 見出しパーマリンク (7.5) */
.prose h2 .anchor, .prose h3 .anchor, .prose h4 .anchor {
  opacity: 0;
  margin-left: 0.4rem;
  font-size: 0.85em;
  text-decoration: none;
  color: var(--text-muted);
  transition: opacity var(--transition);
}
.prose h2:hover .anchor,
.prose h3:hover .anchor,
.prose h4:hover .anchor { opacity: 1; }

/* リンク */
.prose a {
  color: var(--accent);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color var(--transition), color var(--transition);
}
.prose a:hover { color: var(--accent-hover); border-bottom-color: var(--accent-hover); }

/* 外部リンクアイコン (7.5) */
.prose a[target="_blank"]::after {
  content: " ↗";
  font-size: 0.75em;
  color: var(--text-muted);
}

/* --------------------------------------------------------------------------
   11. バッジ / タグ (F-A03)
   -------------------------------------------------------------------------- */

.badge {
  display: inline-block;
  padding: 0.15em 0.6em;
  font-size: 0.75rem;
  font-weight: 600;
  border-radius: 4px;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}
.badge--onboarding { background: #E8F5E9; color: #2E7D32; }
.badge--research   { background: #E3F2FD; color: #1565C0; }
.badge--knowledge  { background: #EDE7F6; color: #4527A0; }
.badge--projects   { background: #FFF3E0; color: #E65100; }
.badge--meeting    { background: #F3E5F5; color: #6A1B9A; }
[data-theme="dark"] .badge--onboarding { background: #0A2010; color: #81C784; }
[data-theme="dark"] .badge--research   { background: #0A1525; color: #64B5F6; }
[data-theme="dark"] .badge--knowledge  { background: #150A30; color: #B39DDB; }
[data-theme="dark"] .badge--projects   { background: #251505; color: #FFB74D; }
[data-theme="dark"] .badge--meeting    { background: #200A25; color: #CE93D8; }

.tag {
  display: inline-block;
  padding: 0.1em 0.5em;
  font-size: 0.8rem;
  color: var(--accent);
  background: color-mix(in srgb, var(--accent) 10%, transparent);
  border-radius: 4px;
  text-decoration: none;
  transition: background var(--transition);
}
.tag:hover { background: color-mix(in srgb, var(--accent) 20%, transparent); }

/* --------------------------------------------------------------------------
   12. Callout ボックス (7.5)
   -------------------------------------------------------------------------- */

.callout {
  border-radius: 8px;
  border-left-width: 4px;
  border-left-style: solid;
  padding: 0.875rem 1rem;
  margin: 1rem 0;
}
.callout--info    { background: var(--info-bg);    border-color: var(--info-border); }
.callout--warning { background: var(--warning-bg); border-color: var(--warning-border); }
.callout--danger  { background: var(--danger-bg);  border-color: var(--danger-border); }
.callout--tip     { background: var(--tip-bg);     border-color: var(--tip-border); }
.callout__header {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  margin-bottom: 0.4rem;
}
.callout__title { font-weight: 700; font-size: 0.9rem; }
.callout__body { font-size: 0.9rem; }

/* --------------------------------------------------------------------------
   13. カテゴリカード / ページ一覧
   -------------------------------------------------------------------------- */

.category-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 1rem;
  margin: 1.5rem 0;
}
.category-card {
  display: flex;
  align-items: flex-start;
  gap: 0.75rem;
  padding: 1.25rem;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 10px;
  text-decoration: none;
  color: inherit;
  transition: box-shadow var(--transition), border-color var(--transition), transform var(--transition);
}
.category-card:hover {
  box-shadow: var(--shadow-md);
  border-color: var(--accent);
  transform: translateY(-2px);
}
.category-card__icon { font-size: 1.5rem; }
.category-card__title { font-size: 1rem; font-weight: 700; margin-bottom: 0.25rem; }
.category-card__desc  { font-size: 0.85rem; color: var(--text-secondary); margin-bottom: 0.4rem; }
.category-card__count { font-size: 0.75rem; color: var(--text-muted); }

.page-list { display: flex; flex-direction: column; gap: 0.5rem; margin-top: 1rem; }
.page-list__item {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.875rem 1rem;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 8px;
  text-decoration: none;
  color: inherit;
  transition: box-shadow var(--transition), border-color var(--transition);
}
.page-list__item:hover { box-shadow: var(--shadow-sm); border-color: var(--accent); }
.page-list__title { font-weight: 600; font-size: 0.95rem; margin-bottom: 0.25rem; }
.page-list__desc  { font-size: 0.85rem; color: var(--text-secondary); }
.page-list__meta  { display: flex; flex-wrap: wrap; align-items: center; gap: 0.4rem; flex-shrink: 0; }
.page-list__date  { font-size: 0.8rem; color: var(--text-muted); white-space: nowrap; }

.empty-state {
  text-align: center;
  color: var(--text-muted);
  padding: 3rem 0;
  font-size: 0.95rem;
  line-height: 1.8;
}

/* --------------------------------------------------------------------------
   14. 関連ページ (F-B03)
   -------------------------------------------------------------------------- */

.related-pages { margin-top: 3rem; padding-top: 1.5rem; border-top: 1px solid var(--border); }
.related-pages__heading { font-size: 1rem; font-weight: 700; margin-bottom: 1rem; }
.related-pages__grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: 0.75rem;
}
.related-card {
  display: flex;
  flex-direction: column;
  gap: 0.3rem;
  padding: 0.875rem;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 8px;
  text-decoration: none;
  color: inherit;
  transition: var(--transition);
}
.related-card:hover { border-color: var(--accent); box-shadow: var(--shadow-sm); }
.related-card__title { font-size: 0.9rem; font-weight: 600; color: var(--text-primary); }
.related-card__desc  { font-size: 0.8rem; color: var(--text-muted); }

/* --------------------------------------------------------------------------
   15. ページナビゲーション
   -------------------------------------------------------------------------- */

.page-nav {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  margin-top: 2.5rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--border);
}
.page-nav__link {
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
  padding: 0.75rem 1rem;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 8px;
  text-decoration: none;
  color: inherit;
  flex: 1;
  max-width: 48%;
  transition: var(--transition);
}
.page-nav__link:hover { border-color: var(--accent); }
.page-nav__link--next { align-items: flex-end; text-align: right; }
.page-nav__label { font-size: 0.75rem; color: var(--text-muted); }
.page-nav__title { font-size: 0.9rem; font-weight: 600; color: var(--accent); }

/* --------------------------------------------------------------------------
   16. 最近の更新
   -------------------------------------------------------------------------- */

.section-heading {
  font-family: var(--font-serif);
  font-size: 1.2rem;
  margin: 2rem 0 1rem;
  padding-bottom: 0.4rem;
  border-bottom: 1px solid var(--border);
}
.recent-list { list-style: none; }
.recent-list__item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.5rem 0;
  border-bottom: 1px solid var(--border);
}
.recent-list__link { font-size: 0.9rem; color: var(--accent); text-decoration: none; }
.recent-list__link:hover { text-decoration: underline; }
.recent-list__meta { display: flex; align-items: center; gap: 0.5rem; flex-shrink: 0; }
.recent-list__meta time { font-size: 0.8rem; color: var(--text-muted); }

/* --------------------------------------------------------------------------
   17. フッター (7.4)
   -------------------------------------------------------------------------- */

.site-footer {
  border-top: 1px solid var(--border);
  background: var(--bg-sidebar);
  padding: 1rem 1.5rem;
  transition: background-color var(--transition);
}
.site-footer__inner {
  display: flex;
  align-items: center;
  gap: 1.5rem;
  font-size: 0.8rem;
  color: var(--text-muted);
  flex-wrap: wrap;
}
.site-footer__gh { color: var(--text-muted); text-decoration: none; display: flex; align-items: center; gap: 0.3rem; }
.site-footer__gh:hover { color: var(--accent); }
.site-footer__copy a { color: var(--text-muted); }
.site-footer__copy a:hover { color: var(--accent); }

/* Back to Top */
.back-to-top {
  position: fixed;
  bottom: 1.5rem;
  right: 1.5rem;
  width: 40px;
  height: 40px;
  background: var(--accent);
  color: white;
  border: none;
  border-radius: 50%;
  cursor: pointer;
  font-size: 1rem;
  box-shadow: var(--shadow-md);
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--transition), transform var(--transition);
  z-index: 50;
}
.back-to-top.is-visible { opacity: 1; pointer-events: auto; }
.back-to-top:hover { transform: translateY(-3px); }

/* --------------------------------------------------------------------------
   18. ページヘッダ共通
   -------------------------------------------------------------------------- */

.page-header { margin-bottom: 2rem; }
.page-title { font-family: var(--font-serif); font-size: 1.8rem; line-height: 1.4; }
.page-description { font-size: 1.05rem; color: var(--text-secondary); margin-top: 0.5rem; }

/* --------------------------------------------------------------------------
   19. レスポンシブ (7.4)
   -------------------------------------------------------------------------- */

/* < 1200px: ToC 非表示 */
@media (max-width: 1200px) {
  .layout {
    grid-template-columns: var(--sidebar-width) 1fr;
  }
  .toc { display: none; }
}

/* < 960px: サイドバー → ドロワー */
@media (max-width: 960px) {
  .layout {
    grid-template-columns: 1fr;
  }
  .hamburger { display: flex; }
  .search-box__kbd { display: none; }

  .sidebar {
    position: fixed;
    top: var(--header-height);
    left: 0;
    bottom: 0;
    width: var(--sidebar-width);
    z-index: 90;
    transform: translateX(-100%);
    transition: transform 0.25s ease;
    box-shadow: var(--shadow-lg);
  }
  .sidebar.is-open { transform: translateX(0); }
  .sidebar__overlay {
    display: block;
    position: fixed;
    inset: 0;
    top: var(--header-height);
    background: rgba(0,0,0,.4);
    z-index: 89;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.25s ease;
  }
  .sidebar.is-open .sidebar__overlay {
    opacity: 1;
    pointer-events: auto;
  }
  .main-content { padding: 1.5rem 1rem; }
}

@media (max-width: 600px) {
  .site-header__logo-text { display: none; }
  .search-wrapper { max-width: none; }
  .category-grid { grid-template-columns: 1fr; }
  .page-nav { flex-direction: column; }
  .page-nav__link { max-width: 100%; }
}

/* --------------------------------------------------------------------------
   20. フォーカスアウトライン (NF-A03 キーボード操作)
   -------------------------------------------------------------------------- */

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
  border-radius: 3px;
}