:root {
  --bg: #f7f8fb;
  --text: #1f2937;
  --muted: #6b7280;
  --line: #e5e7eb;
  --card: #ffffff;
  --accent: #1f4f8f;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Hiragino Kaku Gothic ProN", "Yu Gothic", Meiryo, sans-serif;
  line-height: 1.8;
  color: var(--text);
  background: var(--bg);
}

a {
  color: var(--accent);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

.container {
  width: min(1080px, calc(100% - 32px));
  margin: 0 auto;
}

.site-header {
  background: #ffffff;
  border-bottom: 1px solid var(--line);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 16px 0;
}

.site-logo {
  font-weight: 700;
  font-size: 20px;
  color: var(--text);
}

.site-nav {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
  font-size: 14px;
}

.site-main {
  min-height: 70vh;
}

.hero {
  padding: 72px 0 56px;
  background: #ffffff;
  border-bottom: 1px solid var(--line);
}

.eyebrow {
  color: var(--accent);
  font-weight: 700;
  margin: 0 0 8px;
}

h1 {
  font-size: clamp(32px, 5vw, 48px);
  line-height: 1.3;
  margin: 0 0 16px;
}

h2 {
  font-size: 28px;
  line-height: 1.4;
  margin: 0 0 20px;
}

h3 {
  font-size: 20px;
  margin: 0 0 8px;
}

.lead {
  max-width: 760px;
  font-size: 18px;
  color: var(--muted);
}

.section {
  padding: 48px 0;
}

.card-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}

.card,
.post-item {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 22px;
}

.muted {
  color: var(--muted);
}

.article {
  max-width: 860px;
  padding: 40px 0 64px;
}

.article-header {
  margin-bottom: 28px;
}

.article-meta {
  color: var(--muted);
  font-size: 14px;
}

.article-content {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 28px;
}

.article-content h2 {
  margin-top: 40px;
  padding-top: 20px;
  border-top: 1px solid var(--line);
}

.article-content h3 {
  margin-top: 28px;
}

.pr-box {
  background: #fff7ed;
  border: 1px solid #fed7aa;
  border-radius: 12px;
  padding: 12px 14px;
  margin-bottom: 20px;
  font-size: 14px;
}

.site-footer {
  background: #ffffff;
  border-top: 1px solid var(--line);
  padding: 28px 0;
  color: var(--muted);
  font-size: 14px;
}

.footer-note {
  margin: 4px 0 0;
}

@media (max-width: 800px) {
  .header-inner {
    align-items: flex-start;
    flex-direction: column;
  }

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

  .article-content {
    padding: 20px;
  }
}