:root {
  --bg: #eff2ef;
  --text: #333333;
  --muted: #4a7a4a;
  --accent: #25ce25;
  --card: #ffffff;
  --border: #c8d4c8;
  --max: 1100px;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: "Hiragino Kaku Gothic ProN", "Hiragino Kaku Gothic Pro", "Yu Gothic", "Noto Sans JP", sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.8;
}

.wrap {
  max-width: var(--max);
  margin: 0 auto;
  padding: 18px;
}

.topbar {
  border-bottom: 1px solid var(--border);
  background: #e5ebe5;
}

.topbar-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.site-title {
  font-size: 1.1rem;
  color: var(--text);
  text-decoration: none;
  font-weight: 700;
}

.site-nav a {
  margin-left: 10px;
  text-decoration: none;
  color: var(--muted);
  font-size: 0.9rem;
}

.site-nav a:hover {
  color: var(--accent);
}

.layout {
  display: grid;
  grid-template-columns: 260px 1fr;
  gap: 16px;
}

h1, h2, h3 {
  line-height: 1.3;
}

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

.post-meta {
  color: var(--muted);
  margin-top: -8px;
}

.post-categories {
  color: var(--muted);
  font-size: 0.95rem;
}

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

.post-list li {
  padding: 10px 0;
  border-bottom: 1px solid var(--border);
}

.panel {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 16px;
  box-shadow: 0 1px 0 rgba(0, 0, 0, 0.05);
}

.content-panel {
  min-height: 240px;
}

.panel-title {
  font-weight: 700;
  margin-bottom: 8px;
}

.panel-text {
  color: var(--muted);
  font-size: 0.95rem;
}

.button {
  display: inline-block;
  background: var(--accent);
  color: #ffffff;
  text-decoration: none;
  padding: 8px 12px;
  border-radius: 8px;
  font-weight: 700;
  font-size: 0.9rem;
}

.category-list {
  list-style: none;
  padding: 0;
  margin: 0 0 24px 0;
}

.category-list li {
  padding: 4px 0;
}

.site-footer {
  border-top: 1px solid var(--border);
  color: var(--muted);
  font-size: 0.9rem;
}

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

@media (max-width: 640px) {
  .wrap {
    padding: 16px;
  }

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

  .topbar-inner {
    flex-direction: column;
    align-items: flex-start;
  }
}