/* ==========================================================
   base.css — 共通レイアウト & コンポーネント
   色・フォントは各テーマの CSS 変数で上書きする
   ========================================================== */

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

:root {
  --container-width: 1140px;
  --header-height: 60px;
  --sidebar-width: 300px;
  --gap: 2rem;
  --radius: 6px;
  --shadow-sm: 0 1px 4px rgba(0,0,0,.08);
  --shadow-md: 0 4px 16px rgba(0,0,0,.12);
}

body {
  font-family: var(--font-body, 'Hiragino Sans', 'Noto Sans JP', sans-serif);
  font-size: var(--font-size-base, 1rem);
  line-height: 1.8;
  background: var(--color-bg, #fff);
  color: var(--color-text, #333);
}

img { display: block; max-width: 100%; height: auto; }

/* ----------------------------------------------------------
   Container
   ---------------------------------------------------------- */
.container {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 1.25rem;
}

/* ----------------------------------------------------------
   Header
   ---------------------------------------------------------- */
.site-header {
  background: var(--color-header-bg, #333);
  color: var(--color-header-text, #fff);
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: 0 2px 8px rgba(0,0,0,.25);
}

.header-inner {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 1.25rem;
}

.header-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: var(--header-height);
}

.site-logo {
  font-family: var(--font-heading, inherit);
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--color-header-text, #fff);
  text-decoration: none;
  letter-spacing: .04em;
  flex-shrink: 0;
}
.site-logo:hover { opacity: .85; }

/* カテゴリーナビ */
.header-nav {
  display: flex;
  align-items: center;
  gap: .25rem;
  padding: .4rem 0;
  overflow-x: auto;
  scrollbar-width: none;
  border-top: 1px solid rgba(255,255,255,.1);
}
.header-nav::-webkit-scrollbar { display: none; }

.nav-link {
  display: inline-block;
  font-size: .82rem;
  font-weight: 600;
  color: var(--color-header-text, #fff);
  text-decoration: none;
  padding: .3rem .75rem;
  border-radius: 999px;
  white-space: nowrap;
  transition: background .15s, color .15s;
  opacity: .8;
}
.nav-link:hover {
  background: rgba(255,255,255,.15);
  opacity: 1;
}

/* ハンバーガーボタン（モバイル） */
.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 36px;
  height: 36px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}
.nav-toggle span {
  display: block;
  width: 100%;
  height: 2px;
  background: var(--color-header-text, #fff);
  border-radius: 2px;
  transition: transform .25s, opacity .25s;
}

/* ----------------------------------------------------------
   Main
   ---------------------------------------------------------- */
.site-main {
  min-height: calc(100vh - var(--header-height) - 120px);
  padding: 2rem 0 3rem;
}

/* ----------------------------------------------------------
   2カラム レイアウト
   ---------------------------------------------------------- */
.layout-wrapper {
  display: grid;
  grid-template-columns: 1fr var(--sidebar-width);
  gap: var(--gap);
  align-items: start;
}

.layout-main { min-width: 0; }

/* ----------------------------------------------------------
   パンくずリスト
   ---------------------------------------------------------- */
.breadcrumb {
  margin-bottom: 1.25rem;
}
.breadcrumb__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  list-style: none;
  gap: .25rem;
  font-size: .8rem;
  color: var(--color-text-muted, #888);
}
.breadcrumb__item a {
  color: var(--color-accent, #555);
  text-decoration: none;
}
.breadcrumb__item a:hover { text-decoration: underline; }
.breadcrumb__item + .breadcrumb__item::before {
  content: '›';
  margin-right: .25rem;
  color: var(--color-text-muted, #aaa);
}
.breadcrumb__item--current { color: var(--color-text-muted, #888); }

/* ----------------------------------------------------------
   Page title / category header
   ---------------------------------------------------------- */
.page-title {
  font-family: var(--font-heading, inherit);
  font-size: 1.6rem;
  font-weight: 700;
  color: var(--color-heading, #333);
  margin-bottom: 1.5rem;
  padding-bottom: .6rem;
  border-bottom: 3px solid var(--color-accent, #555);
}

.category-header { margin-bottom: 1.5rem; }

.category-desc {
  color: var(--color-text-muted, #666);
  margin-top: .5rem;
  font-size: .95rem;
}

/* ----------------------------------------------------------
   記事カード（一覧）
   ---------------------------------------------------------- */
.article-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.25rem;
}

.article-card {
  background: var(--color-card-bg, #fff);
  border: 1px solid var(--color-border, #e5e5e5);
  border-radius: var(--radius);
  overflow: hidden;
  display: flex;
  flex-direction: column;
  transition: box-shadow .2s, transform .2s;
}
.article-card:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-3px);
}

.article-card__thumb-link { display: block; overflow: hidden; aspect-ratio: 16/9; }
.article-card__thumb {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform .3s;
}
.article-card:hover .article-card__thumb { transform: scale(1.04); }
.article-card__thumb--placeholder {
  width: 100%;
  height: 100%;
  background: var(--color-accent-light, #f0f0f0);
}

.article-card__body {
  padding: 1rem 1.1rem 1.2rem;
  display: flex;
  flex-direction: column;
  flex: 1;
}

.article-card__cat {
  display: inline-block;
  font-size: .72rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: .06em;
  color: var(--color-accent, #555);
  background: var(--color-accent-light, #f0f0f0);
  padding: .15rem .6rem;
  border-radius: 999px;
  text-decoration: none;
  margin-bottom: .5rem;
  align-self: flex-start;
}
.article-card__cat:hover { opacity: .8; }

.article-card__title {
  font-family: var(--font-heading, inherit);
  font-size: .97rem;
  font-weight: 700;
  line-height: 1.45;
  margin-bottom: .4rem;
  flex: 1;
}
.article-card__title a {
  color: var(--color-heading, #333);
  text-decoration: none;
}
.article-card__title a:hover { color: var(--color-accent, #555); }

.article-card__date {
  display: block;
  font-size: .75rem;
  color: var(--color-text-muted, #888);
  margin-bottom: .4rem;
}

.article-card__excerpt {
  font-size: .85rem;
  color: var(--color-text-muted, #666);
  line-height: 1.6;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

/* ----------------------------------------------------------
   記事詳細
   ---------------------------------------------------------- */
.article-hero {
  margin-bottom: 1.75rem;
  border-radius: var(--radius);
  overflow: hidden;
}
.article-hero__img {
  width: 100%;
  height: auto;
  object-fit: cover;
  border-radius: var(--radius);
}

.article-header { margin-bottom: 1.5rem; }

.article-category {
  display: inline-block;
  font-size: .75rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: .06em;
  color: var(--color-accent, #555);
  text-decoration: none;
  background: var(--color-accent-light, #f0f0f0);
  padding: .2rem .75rem;
  border-radius: 999px;
  margin-bottom: .8rem;
}
.article-category:hover { opacity: .8; }

.article-title {
  font-family: var(--font-heading, inherit);
  font-size: 1.75rem;
  font-weight: 700;
  color: var(--color-heading, #333);
  line-height: 1.4;
  margin-bottom: .65rem;
}

.article-meta {
  display: flex;
  align-items: center;
  gap: 1rem;
  flex-wrap: wrap;
}

.article-date {
  font-size: .82rem;
  color: var(--color-text-muted, #888);
}

.article-reading-time {
  font-size: .8rem;
  color: var(--color-text-muted, #888);
  padding: .15rem .6rem;
  background: var(--color-accent-light, #f5f5f5);
  border-radius: 999px;
}

/* Article body */
.article-body {
  font-size: 1rem;
  line-height: 1.95;
}

.article-body h2 {
  font-family: var(--font-heading, inherit);
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--color-heading, #333);
  margin: 2.25rem 0 .75rem;
  padding: .5rem .75rem;
  background: var(--color-accent-light, #f9f9f9);
  border-left: 4px solid var(--color-accent, #555);
  border-radius: 0 var(--radius) var(--radius) 0;
}

.article-body h3 {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--color-heading, #333);
  margin: 1.75rem 0 .6rem;
  padding-bottom: .35rem;
  border-bottom: 2px solid var(--color-border, #e5e5e5);
}

.article-body h4 {
  font-size: 1rem;
  font-weight: 700;
  margin: 1.25rem 0 .4rem;
}

.article-body p { margin-bottom: 1.25rem; }

.article-body a {
  color: var(--color-accent, #555);
  text-decoration: underline;
  text-underline-offset: 2px;
}
.article-body a:hover { opacity: .75; }

.article-body ul,
.article-body ol {
  margin: 0 0 1.25rem 1.5rem;
}
.article-body li { margin-bottom: .4rem; }

.article-body img {
  max-width: 100%;
  height: auto;
  border-radius: var(--radius);
  margin: 1.25rem 0;
}

.article-body blockquote {
  border-left: 4px solid var(--color-accent, #ccc);
  padding: .75rem 1.25rem;
  margin: 1.5rem 0;
  background: var(--color-accent-light, #f9f9f9);
  color: var(--color-text-muted, #555);
  font-style: italic;
  border-radius: 0 var(--radius) var(--radius) 0;
}

.article-body table {
  width: 100%;
  border-collapse: collapse;
  margin-bottom: 1.5rem;
  font-size: .9rem;
}
.article-body th,
.article-body td {
  padding: .6rem .85rem;
  border: 1px solid var(--color-border, #ddd);
  text-align: left;
  vertical-align: top;
}
.article-body th {
  background: var(--color-accent-light, #f5f5f5);
  font-weight: 700;
}
.article-body tr:nth-child(even) td { background: rgba(0,0,0,.02); }

/* ----------------------------------------------------------
   シェアボタン
   ---------------------------------------------------------- */
.article-footer {
  margin-top: 2.5rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--color-border, #e5e5e5);
}

.share-buttons {
  display: flex;
  align-items: center;
  gap: .65rem;
  flex-wrap: wrap;
}

.share-buttons__label {
  font-size: .85rem;
  font-weight: 700;
  color: var(--color-text-muted, #888);
  margin-right: .25rem;
}

.share-btn {
  display: inline-flex;
  align-items: center;
  gap: .4rem;
  font-size: .82rem;
  font-weight: 700;
  padding: .45rem 1rem;
  border-radius: 999px;
  text-decoration: none;
  border: none;
  cursor: pointer;
  transition: opacity .15s, transform .1s;
}
.share-btn:hover { opacity: .85; transform: translateY(-1px); }
.share-btn:active { transform: translateY(0); }

.share-btn svg {
  width: 16px;
  height: 16px;
  fill: currentColor;
  flex-shrink: 0;
}

.share-btn--twitter  { background: #000; color: #fff; }
.share-btn--hatena   { background: #00a4de; color: #fff; }
.share-btn--copy     { background: var(--color-accent-light, #f0f0f0); color: var(--color-text, #333); border: 1px solid var(--color-border, #ddd); }

/* ----------------------------------------------------------
   サイドバー
   ---------------------------------------------------------- */
.sidebar {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.widget {
  background: var(--color-card-bg, #fff);
  border: 1px solid var(--color-border, #e5e5e5);
  border-radius: var(--radius);
  overflow: hidden;
}

.widget-title {
  font-family: var(--font-heading, inherit);
  font-size: .9rem;
  font-weight: 700;
  letter-spacing: .04em;
  text-transform: uppercase;
  color: var(--color-header-text, #fff);
  background: var(--color-header-bg, #333);
  padding: .6rem 1rem;
}

/* 著者紹介 */
.widget-author {
  padding: 1.25rem 1rem;
  text-align: center;
}
.widget-author-avatar {
  width: 64px;
  height: 64px;
  border-radius: 50%;
  background: var(--color-accent-light, #f0f0f0);
  margin: 0 auto .75rem;
  color: var(--color-accent, #aaa);
  display: flex;
  align-items: center;
  justify-content: center;
}
.widget-author-avatar svg { width: 64px; height: 64px; }
.widget-author-name {
  font-weight: 700;
  font-size: .95rem;
  margin-bottom: .4rem;
  color: var(--color-heading, #333);
}
.widget-author-bio {
  font-size: .82rem;
  color: var(--color-text-muted, #888);
  line-height: 1.65;
}

/* カテゴリーウィジェット */
.widget-category-list {
  list-style: none;
  padding: .5rem 0;
}
.widget-category-list li { border-bottom: 1px solid var(--color-border, #f0f0f0); }
.widget-category-list li:last-child { border-bottom: none; }
.widget-category-list a {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: .55rem 1rem;
  font-size: .88rem;
  color: var(--color-text, #333);
  text-decoration: none;
  transition: background .15s;
}
.widget-category-list a:hover { background: var(--color-accent-light, #f9f9f9); }

.cat-count {
  font-size: .75rem;
  color: var(--color-text-muted, #aaa);
  background: var(--color-accent-light, #f0f0f0);
  padding: .1rem .5rem;
  border-radius: 999px;
}

/* 記事リストウィジェット */
.widget-post-list {
  list-style: none;
  padding: .5rem 0;
}
.widget-post-item {
  display: flex;
  gap: .75rem;
  align-items: flex-start;
  padding: .65rem 1rem;
  border-bottom: 1px solid var(--color-border, #f0f0f0);
}
.widget-post-item:last-child { border-bottom: none; }

.widget-post-thumb {
  flex-shrink: 0;
  width: 72px;
  height: 48px;
  border-radius: 4px;
  overflow: hidden;
  display: block;
}
.widget-post-thumb img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.widget-post-body { min-width: 0; }
.widget-post-title {
  display: block;
  font-size: .83rem;
  font-weight: 600;
  color: var(--color-heading, #333);
  text-decoration: none;
  line-height: 1.45;
  margin-bottom: .2rem;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}
.widget-post-title:hover { color: var(--color-accent, #555); }
.widget-post-date {
  font-size: .72rem;
  color: var(--color-text-muted, #aaa);
}

/* ----------------------------------------------------------
   Footer
   ---------------------------------------------------------- */
.site-footer {
  background: var(--color-footer-bg, #222);
  color: var(--color-footer-text, #aaa);
  padding: 2.5rem 0 0;
  font-size: .88rem;
}

.footer-inner {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 1.25rem;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.5fr 1fr;
  gap: 2rem;
  padding-bottom: 2rem;
}

.footer-logo {
  display: inline-block;
  font-family: var(--font-heading, inherit);
  font-size: 1.1rem;
  font-weight: 700;
  color: #fff;
  text-decoration: none;
  margin-bottom: .75rem;
}
.footer-logo:hover { opacity: .85; }

.footer-desc {
  font-size: .85rem;
  line-height: 1.7;
  color: var(--color-footer-text, #aaa);
  max-width: 360px;
}

.footer-heading {
  font-size: .82rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: .06em;
  color: #fff;
  margin-bottom: .75rem;
  padding-bottom: .4rem;
  border-bottom: 1px solid rgba(255,255,255,.12);
}

.footer-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: .3rem;
}
.footer-links a {
  font-size: .85rem;
  color: var(--color-footer-text, #aaa);
  text-decoration: none;
  transition: color .15s;
}
.footer-links a:hover { color: #fff; }

.footer-bottom {
  border-top: 1px solid rgba(255,255,255,.08);
  padding: 1.1rem 0;
  text-align: center;
  font-size: .8rem;
  color: var(--color-footer-text, #aaa);
}

/* ----------------------------------------------------------
   件数表示
   ---------------------------------------------------------- */
.article-count {
  font-size: .82rem;
  color: var(--color-text-muted, #888);
  margin-bottom: 1rem;
}

/* ----------------------------------------------------------
   ページネーション
   ---------------------------------------------------------- */
.pagination {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: .35rem;
  margin-top: 2rem;
  flex-wrap: wrap;
}

.pagination__btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 2.2rem;
  height: 2.2rem;
  padding: 0 .5rem;
  border-radius: var(--radius);
  font-size: .9rem;
  font-weight: 600;
  text-decoration: none;
  color: var(--color-text, #333);
  background: var(--color-card-bg, #fff);
  border: 1px solid var(--color-border, #ddd);
  transition: background .15s, color .15s;
}
.pagination__btn:hover {
  background: var(--color-accent-light, #f0f0f0);
  color: var(--color-accent, #555);
}
.pagination__btn--current {
  background: var(--color-accent, #555);
  color: #fff;
  border-color: var(--color-accent, #555);
  pointer-events: none;
}
.pagination__btn--disabled {
  opacity: .35;
  pointer-events: none;
  border: 1px solid var(--color-border, #ddd);
  background: transparent;
}
.pagination__btn--prev,
.pagination__btn--next { font-size: 1.1rem; }

.pagination__ellipsis {
  color: var(--color-text-muted, #aaa);
  font-size: .9rem;
  line-height: 2.2rem;
}

/* ----------------------------------------------------------
   関連記事
   ---------------------------------------------------------- */
.related-articles {
  margin-top: 2.5rem;
  padding-top: 2rem;
  border-top: 1px solid var(--color-border, #e5e5e5);
}

.related-articles__title {
  font-family: var(--font-heading, inherit);
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--color-heading, #333);
  margin-bottom: 1.25rem;
  padding-left: .75rem;
  border-left: 4px solid var(--color-accent, #555);
}

.related-articles__grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1rem;
}

.related-card {
  background: var(--color-card-bg, #fff);
  border: 1px solid var(--color-border, #e5e5e5);
  border-radius: var(--radius);
  overflow: hidden;
  transition: box-shadow .2s, transform .2s;
}
.related-card:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

.related-card__thumb-link { display: block; aspect-ratio: 16/9; overflow: hidden; }
.related-card__thumb {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform .3s;
}
.related-card:hover .related-card__thumb { transform: scale(1.05); }
.related-card__thumb--placeholder {
  width: 100%;
  height: 100%;
  background: var(--color-accent-light, #f0f0f0);
}

.related-card__body { padding: .75rem; }

.related-card__title {
  font-size: .85rem;
  font-weight: 600;
  line-height: 1.45;
  margin-bottom: .3rem;
}
.related-card__title a {
  color: var(--color-heading, #333);
  text-decoration: none;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}
.related-card__title a:hover { color: var(--color-accent, #555); }

.related-card__date {
  font-size: .72rem;
  color: var(--color-text-muted, #aaa);
}

/* ----------------------------------------------------------
   サイドバー：カテゴリー別代表記事
   ---------------------------------------------------------- */
.widget-cat-rep-list {
  padding: .5rem 0;
}

.widget-cat-rep {
  padding: .75rem 1rem;
  border-bottom: 1px solid var(--color-border, #f0f0f0);
}
.widget-cat-rep:last-child { border-bottom: none; }

.widget-cat-rep__label {
  display: inline-block;
  font-size: .72rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: .05em;
  color: var(--color-accent, #555);
  background: var(--color-accent-light, #f0f0f0);
  padding: .1rem .55rem;
  border-radius: 999px;
  text-decoration: none;
  margin-bottom: .5rem;
}
.widget-cat-rep__label:hover { opacity: .8; }

.widget-cat-rep__card {
  display: block;
  text-decoration: none;
}
.widget-cat-rep__card:hover .widget-cat-rep__title {
  color: var(--color-accent, #555);
}

.widget-cat-rep__thumb {
  width: 100%;
  aspect-ratio: 16/9;
  object-fit: cover;
  border-radius: 4px;
  margin-bottom: .4rem;
  display: block;
}
.widget-cat-rep__thumb--placeholder {
  width: 100%;
  aspect-ratio: 16/9;
  background: var(--color-accent-light, #f0f0f0);
  border-radius: 4px;
  margin-bottom: .4rem;
}

.widget-cat-rep__title {
  font-size: .83rem;
  font-weight: 600;
  color: var(--color-heading, #333);
  line-height: 1.45;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
  transition: color .15s;
}

/* ----------------------------------------------------------
   Empty / utility
   ---------------------------------------------------------- */
.empty-message {
  padding: 2rem;
  text-align: center;
  color: var(--color-text-muted, #888);
  background: var(--color-card-bg, #fff);
  border: 1px solid var(--color-border, #e5e5e5);
  border-radius: var(--radius);
}

/* ----------------------------------------------------------
   Responsive — タブレット（900px以下）
   ---------------------------------------------------------- */
@media (max-width: 900px) {
  :root { --sidebar-width: 260px; }

  .article-grid { grid-template-columns: 1fr; }

  .related-articles__grid { grid-template-columns: repeat(2, 1fr); }
}

/* ----------------------------------------------------------
   Responsive — モバイル（640px以下）
   ---------------------------------------------------------- */
@media (max-width: 640px) {
  :root { --header-height: 52px; }

  .nav-toggle { display: flex; }

  .header-nav {
    display: none;
    flex-direction: column;
    align-items: flex-start;
    padding: .5rem 0 .75rem;
    gap: .1rem;
  }
  .header-nav.is-open { display: flex; }
  .nav-link { font-size: .9rem; padding: .5rem .75rem; width: 100%; border-radius: var(--radius); }

  .layout-wrapper {
    grid-template-columns: 1fr;
  }

  .footer-grid {
    grid-template-columns: 1fr;
    gap: 1.25rem;
  }

  .page-title    { font-size: 1.35rem; }
  .article-title { font-size: 1.35rem; }
  .article-grid  { gap: 1rem; }

  .share-buttons { gap: .5rem; }
  .share-btn { font-size: .78rem; padding: .4rem .8rem; }

  .related-articles__grid { grid-template-columns: 1fr; }
}