/* ----- リセット ----- */
*, *::before, *::after { box-sizing: border-box; }
body, h1, h2, h3, p, ul, ol, figure { margin: 0; padding: 0; }

/* ----- ベース ----- */
:root {
  --color-bg: #fafaf7;
  --color-text: #2a2a2a;
  --color-muted: #7a7a7a;
  --color-accent: #a86b3d;
  --color-border: #e7e3da;
  --font-sans: -apple-system, BlinkMacSystemFont, "Hiragino Kaku Gothic ProN",
               "Noto Sans JP", "Yu Gothic", "Meiryo", sans-serif;
  --font-serif: "Hiragino Mincho ProN", "Yu Mincho", "Noto Serif JP", serif;
  --maxw: 720px;
}

html { font-size: 16px; }

body {
  font-family: var(--font-sans);
  background: var(--color-bg);
  color: var(--color-text);
  line-height: 1.8;
  -webkit-font-smoothing: antialiased;
}

a {
  color: var(--color-accent);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-color .15s ease;
}
a:hover { border-bottom-color: var(--color-accent); }

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

/* ----- ヘッダー ----- */
.site-header {
  padding: 2.5rem 0 1.5rem;
  border-bottom: 1px solid var(--color-border);
  margin-bottom: 3rem;
}

.site-header .container {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  flex-wrap: wrap;
  gap: 1rem;
}

.site-title {
  font-family: var(--font-serif);
  font-size: 1.5rem;
  font-weight: 500;
  letter-spacing: 0.02em;
}
.site-title a {
  color: var(--color-text);
  border-bottom: none;
}

.site-nav a {
  color: var(--color-muted);
  margin-left: 1.25rem;
  font-size: 0.9rem;
}
.site-nav a:first-child { margin-left: 0; }

/* ----- 本文共通 ----- */
main { padding-bottom: 4rem; }

.intro {
  color: var(--color-muted);
  font-size: 0.95rem;
  margin-bottom: 3rem;
  padding-bottom: 1.5rem;
  border-bottom: 1px dashed var(--color-border);
}

/* ----- 記事一覧 ----- */
.post-list h2 {
  font-family: var(--font-serif);
  font-size: 1.1rem;
  font-weight: 500;
  color: var(--color-muted);
  margin-bottom: 2rem;
  letter-spacing: 0.1em;
}

.post-summary {
  padding: 1.5rem 0;
  border-bottom: 1px solid var(--color-border);
}
.post-summary:last-child { border-bottom: none; }

.post-summary time {
  display: block;
  color: var(--color-muted);
  font-size: 0.85rem;
  margin-bottom: 0.5rem;
}

.post-summary h3 {
  font-family: var(--font-serif);
  font-size: 1.35rem;
  font-weight: 500;
  line-height: 1.5;
  margin-bottom: 0.75rem;
}
.post-summary h3 a {
  color: var(--color-text);
  border-bottom: none;
}
.post-summary h3 a:hover { color: var(--color-accent); }

.post-summary p {
  color: #4a4a4a;
  margin-bottom: 0.75rem;
}

.read-more {
  font-size: 0.9rem;
}

/* ----- 記事ページ ----- */
.post-article {
  font-family: var(--font-serif);
}
.post-article header {
  margin-bottom: 2.5rem;
  padding-bottom: 1.5rem;
  border-bottom: 1px solid var(--color-border);
}
.post-article time {
  color: var(--color-muted);
  font-size: 0.85rem;
  font-family: var(--font-sans);
}
.post-article h1 {
  font-size: 1.8rem;
  font-weight: 500;
  line-height: 1.5;
  margin-top: 0.5rem;
}

.post-body { font-size: 1.05rem; }
.post-body h2 {
  font-size: 1.3rem;
  font-weight: 500;
  margin: 2.5rem 0 1rem;
  padding-left: 0.75rem;
  border-left: 3px solid var(--color-accent);
}
.post-body h3 {
  font-size: 1.1rem;
  font-weight: 500;
  margin: 2rem 0 0.75rem;
}
.post-body p { margin-bottom: 1.25rem; }
.post-body ul, .post-body ol {
  margin: 0 0 1.25rem 1.5rem;
}
.post-body li { margin-bottom: 0.25rem; }
.post-body blockquote {
  border-left: 3px solid var(--color-border);
  padding-left: 1rem;
  color: var(--color-muted);
  margin: 1.5rem 0;
  font-style: italic;
}
.post-body code {
  background: #eee9de;
  padding: 0.1em 0.4em;
  border-radius: 3px;
  font-size: 0.9em;
  font-family: SFMono-Regular, Menlo, Consolas, monospace;
}
.post-body img {
  max-width: 100%;
  height: auto;
  border-radius: 4px;
  margin: 1.5rem 0;
}

.post-footer {
  margin-top: 3rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--color-border);
  font-family: var(--font-sans);
  font-size: 0.9rem;
}

/* ----- フッター ----- */
.site-footer {
  border-top: 1px solid var(--color-border);
  padding: 2rem 0;
  text-align: center;
  font-size: 0.85rem;
  color: var(--color-muted);
}

/* ----- レスポンシブ ----- */
@media (max-width: 600px) {
  .site-header { padding-top: 1.5rem; margin-bottom: 2rem; }
  .site-title { font-size: 1.3rem; }
  .post-summary h3 { font-size: 1.15rem; }
  .post-article h1 { font-size: 1.5rem; }
}