:root {
  --color-teal: #1a5f5f;
  --color-teal-dark: #123f3f;
  --color-bg: #faf8f4;
  --color-text: #2b2b2b;
  --color-cream: #f3ede0;
  --color-card-bg: #e9eee1;
  --color-card-bg-hover: #dce6d5;
  --color-text-muted: #555;
  --color-text-subtle: #666;
  --color-footer: #5f5f5f;
  --font-jp: 'Noto Serif JP', serif;
  --max-width: 720px;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  background: var(--color-bg);
  color: var(--color-text);
  font-family: var(--font-jp);
  line-height: 1.9;
  -webkit-font-smoothing: antialiased;
}

h1, h2 {
  font-family: var(--font-jp);
  font-weight: normal;
  letter-spacing: 0.05em;
}

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

a:hover {
  color: var(--color-teal-dark);
}

img {
  max-width: 100%;
  display: block;
}

.site-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 24px 20px;
}

.site-header__logo img {
  width: auto;
  height: 48px;
}

.site-nav ul {
  display: flex;
  gap: 24px;
  list-style: none;
}

.site-nav a {
  text-decoration: none;
  font-size: 0.9rem;
}

.hero {
  text-align: center;
  padding: 64px 20px;
}

.hero__logo {
  width: 160px;
  height: auto;
  margin: 0 auto 32px;
}

.hero h1 {
  font-size: 2.5rem;
  color: var(--color-teal);
  margin-bottom: 16px;
}

.hero__tagline {
  font-size: 1.25rem;
  margin-bottom: 8px;
}

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

.section {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 56px 20px;
}

.section h1 {
  font-size: 1.5rem;
  color: var(--color-text);
  margin-bottom: 24px;
}

.section h2 {
  font-size: 1.5rem;
  color: var(--color-teal);
  margin-bottom: 24px;
  border-left: 4px solid var(--color-teal);
  padding-left: 12px;
}

.section p {
  margin-bottom: 1.2em;
}

.section p:last-child {
  margin-bottom: 0;
}

.site-footer {
  text-align: center;
  padding: 32px 20px;
  color: var(--color-footer);
  font-size: 0.85rem;
}

.site-footer a {
  color: var(--color-footer);
  margin-left: 12px;
}

.column-meta {
  color: var(--color-text-subtle);
  font-size: 0.85rem;
  margin-bottom: 1.2em;
}

.column-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: 24px;
  list-style: none;
}

.column-card {
  display: flex;
  flex-direction: column;
  height: 100%;
  padding: 24px;
  background: var(--color-card-bg);
  border-radius: 8px;
  text-decoration: none;
  color: var(--color-text);
  transition: background-color 0.2s ease;
}

.column-card:hover {
  background: var(--color-card-bg-hover);
}

.column-card__title {
  color: var(--color-text);
  font-size: 1.1rem;
  margin-bottom: 8px;
}

.column-card__date {
  color: var(--color-text-subtle);
  font-size: 0.8rem;
  margin-bottom: 12px;
}

.column-card__excerpt {
  font-size: 0.9rem;
  flex-grow: 1;
}

@media (max-width: 600px) {
  .site-header {
    flex-direction: column;
    gap: 12px;
  }

  .site-nav ul {
    gap: 16px;
    flex-wrap: wrap;
    justify-content: center;
  }

  .hero h1 {
    font-size: 2rem;
  }
}