:root {
  --maxw: 760px;
}
[data-theme="dark"] {
  --bg: #14161c;
  --bg-soft: #1c1f27;
  --card: #1c1f27;
  --card-hover: #232733;
  --border: #2c3140;
  --text: #e7e9ee;
  --muted: #9aa1b1;
  --accent: #7aa2ff;
  --accent-soft: #2a3454;
  --code-bg: #11131a;
  --tok-str: #9ece6a;
  --tok-com: #6b7280;
  --tok-num: #e0af68;
  --tok-key: #bb9af7;
}
[data-theme="light"] {
  --bg: #f7f7f5;
  --bg-soft: #ffffff;
  --card: #ffffff;
  --card-hover: #fbfbf9;
  --border: #e3e3dd;
  --text: #23262e;
  --muted: #6b7280;
  --accent: #3b62d4;
  --accent-soft: #e6ecff;
  --code-bg: #f1f2ee;
  --tok-str: #2f7d32;
  --tok-com: #9aa0a6;
  --tok-num: #b4690e;
  --tok-key: #7c3aed;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Hiragino Sans", "Yu Gothic UI", "Segoe UI", Meiryo, sans-serif;
  line-height: 1.8;
  -webkit-font-smoothing: antialiased;
}

/* ---- ヘッダー ---- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  background: color-mix(in srgb, var(--bg) 88%, transparent);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--border);
}
.bar {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 12px 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  color: var(--text);
  font-weight: 700;
}
.brand-mark {
  display: inline-grid;
  place-items: center;
  width: 30px; height: 30px;
  border-radius: 9px;
  background: var(--accent-soft);
  color: var(--accent);
}
.brand-name { font-size: 1.05rem; letter-spacing: .02em; }
.theme-toggle {
  border: 1px solid var(--border);
  background: var(--card);
  color: var(--text);
  width: 38px; height: 38px;
  border-radius: 10px;
  cursor: pointer;
  font-size: 1.1rem;
  transition: background .2s, transform .15s;
}
.theme-toggle:hover { background: var(--card-hover); transform: translateY(-1px); }

/* ---- レイアウト ---- */
.main { max-width: var(--maxw); margin: 0 auto; padding: 28px 20px 64px; }
.intro h1 { font-size: 1.9rem; margin: 8px 0 6px; letter-spacing: .01em; }
.tagline { color: var(--muted); margin: 0 0 8px; }

/* ---- コントロール ---- */
.controls { margin: 22px 0 8px; }
.search {
  width: 100%;
  padding: 11px 14px;
  border-radius: 12px;
  border: 1px solid var(--border);
  background: var(--bg-soft);
  color: var(--text);
  font-size: 1rem;
}
.search:focus { outline: 2px solid var(--accent); outline-offset: 1px; }
.tagbar { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 14px; }
.tag-chip {
  border: 1px solid var(--border);
  background: var(--card);
  color: var(--muted);
  padding: 6px 12px;
  border-radius: 999px;
  font-size: .85rem;
  cursor: pointer;
  transition: background .18s, color .18s, border-color .18s;
}
.tag-chip:hover { background: var(--card-hover); color: var(--text); }
.tag-chip.is-active {
  background: var(--accent-soft);
  color: var(--accent);
  border-color: var(--accent);
  font-weight: 600;
}
.result-info { color: var(--muted); font-size: .9rem; margin: 14px 0 0; }
.empty { color: var(--muted); text-align: center; padding: 40px 0; }

/* ---- 記事カード ---- */
.post-list { display: grid; gap: 16px; margin-top: 20px; }
.post-card {
  display: block;
  text-decoration: none;
  color: var(--text);
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 20px 22px;
  transition: transform .18s ease, border-color .18s, background .18s, box-shadow .18s;
}
.post-card:hover {
  transform: translateY(-3px);
  border-color: var(--accent);
  background: var(--card-hover);
  box-shadow: 0 8px 28px rgba(0,0,0,.18);
}
.card-date { color: var(--muted); font-size: .82rem; margin: 0 0 6px; }
.card-title { font-size: 1.25rem; margin: 0 0 8px; line-height: 1.5; }
.card-summary { color: var(--muted); margin: 0 0 14px; font-size: .95rem; }
.card-tags { display: flex; flex-wrap: wrap; gap: 8px; }
.card-tag { font-size: .78rem; color: var(--accent); background: var(--accent-soft); padding: 3px 9px; border-radius: 999px; }

/* ---- 記事ページ ---- */
.back-link {
  display: inline-block;
  color: var(--muted);
  text-decoration: none;
  font-size: .9rem;
  margin-bottom: 18px;
  transition: color .15s;
}
.back-link:hover { color: var(--accent); }
.article-head { margin-bottom: 8px; }
.article-tags { display: flex; flex-wrap: wrap; gap: 8px; margin-bottom: 10px; }
.article-tag { font-size: .8rem; color: var(--accent); background: var(--accent-soft); padding: 3px 10px; border-radius: 999px; text-decoration: none; }
.article-tag:hover { text-decoration: underline; }
.article h1 { font-size: 1.85rem; line-height: 1.45; margin: 0 0 8px; }
.article-meta { color: var(--muted); font-size: .9rem; margin: 0 0 6px; }

/* ---- 目次 ---- */
.toc {
  background: var(--bg-soft);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 14px 18px;
  margin: 22px 0;
}
.toc-title { font-weight: 700; margin: 0 0 8px; font-size: .9rem; color: var(--muted); }
.toc ul { margin: 0; padding-left: 18px; }
.toc li { margin: 4px 0; }
.toc a { color: var(--accent); text-decoration: none; font-size: .92rem; }
.toc a:hover { text-decoration: underline; }

/* ---- 本文 ---- */
.post-body { font-size: 1.04rem; }
.post-body h2 { font-size: 1.4rem; margin: 34px 0 12px; padding-top: 6px; border-top: 1px solid var(--border); }
.post-body h3 { font-size: 1.15rem; margin: 26px 0 10px; }
.post-body p { margin: 14px 0; }
.post-body ul, .post-body ol { margin: 14px 0; padding-left: 24px; }
.post-body li { margin: 6px 0; }
.post-body a { color: var(--accent); }
.post-body blockquote {
  margin: 18px 0;
  padding: 8px 18px;
  border-left: 4px solid var(--accent);
  background: var(--accent-soft);
  border-radius: 0 10px 10px 0;
  color: var(--text);
}
.post-body hr { border: none; border-top: 1px solid var(--border); margin: 28px 0; }
.inline-code {
  background: var(--code-bg);
  padding: 2px 6px;
  border-radius: 6px;
  font-size: .9em;
  font-family: "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace;
}
.code-block {
  background: var(--code-bg);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 16px 18px;
  overflow-x: auto;
  margin: 18px 0;
}
.code-block code {
  font-family: "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace;
  font-size: .88rem;
  line-height: 1.65;
  color: var(--text);
}
.tok-str { color: var(--tok-str); }
.tok-com { color: var(--tok-com); font-style: italic; }
.tok-num { color: var(--tok-num); }
.tok-key { color: var(--tok-key); font-weight: 600; }

.article-nav { margin-top: 36px; padding-top: 18px; border-top: 1px solid var(--border); }

/* ---- フッター ---- */
.site-footer {
  border-top: 1px solid var(--border);
  color: var(--muted);
  text-align: center;
  font-size: .85rem;
  padding: 24px 20px 40px;
}
.site-footer p { margin: 0; }

@media (max-width: 520px) {
  .article h1 { font-size: 1.5rem; }
  .intro h1 { font-size: 1.6rem; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  * { transition: none !important; }
  .post-card:hover, .theme-toggle:hover { transform: none; }
}