:root {
  --text: #333;
  --muted: #767676;
  --accent: #2e7d6b;
  --bg: #fff;
  --card: #f7f9f8;
  --border: #e0e5e3;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  color: var(--text);
  background: var(--bg);
  font-family: "Hiragino Kaku Gothic ProN", "Hiragino Sans", "Yu Gothic",
    "Noto Sans JP", sans-serif;
  line-height: 1.9;
}

.site-header {
  background: var(--accent);
  color: #fff;
  padding: 28px 16px;
  text-align: center;
}

.site-title { margin: 0; font-size: 1.6em; font-weight: bold; }
.site-title a { color: #fff; text-decoration: none; }
.site-desc { margin: 6px 0 0; font-size: 0.9em; opacity: 0.9; }

main {
  max-width: 760px;
  margin: 0 auto;
  padding: 24px 16px 48px;
}

h1 { font-size: 1.5em; line-height: 1.5; margin: 8px 0 24px; }

h2 {
  font-size: 1.25em;
  border-left: 5px solid var(--accent);
  background: var(--card);
  padding: 10px 14px;
  margin: 40px 0 16px;
  border-radius: 4px;
}

h3 {
  font-size: 1.1em;
  border-bottom: 2px solid var(--border);
  padding-bottom: 6px;
  margin: 32px 0 12px;
}

a { color: var(--accent); }

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

.post-date { color: var(--muted); font-size: 0.85em; margin: 0; }

.post-list { list-style: none; margin: 0; padding: 0; }

.post-card {
  border: 1px solid var(--border);
  border-radius: 10px;
  margin-bottom: 16px;
  background: var(--card);
}

.post-card a {
  display: block;
  padding: 18px 20px;
  text-decoration: none;
  color: inherit;
}

.post-card-title {
  display: block;
  font-weight: bold;
  font-size: 1.05em;
  color: var(--accent);
}

.post-card-date {
  display: block;
  color: var(--muted);
  font-size: 0.8em;
  margin: 4px 0;
}

.post-card-desc { display: block; font-size: 0.9em; color: var(--text); }

.related-posts {
  margin: 32px 0;
  padding: 4px 0;
}

table { border-collapse: collapse; width: 100%; overflow-x: auto; display: block; }
th, td { border: 1px solid var(--border); padding: 8px 12px; }

.site-footer {
  border-top: 1px solid var(--border);
  text-align: center;
  padding: 24px 16px 32px;
  color: var(--muted);
  font-size: 0.85em;
}

.site-footer nav { margin-bottom: 8px; }