:root {
  --teal: #15B0C2;
  --teal-dark: #0E8FA0;
  --navy: #1A3A4A;
  --sky-light: #E8F8FA;
  --sky-lighter: #F4FBFC;
  --white: #ffffff;
  --text: #1A3A4A;
  --subtext: #4A6070;
  --border: #D0E8EC;
}

* { box-sizing: border-box; }

body {
  font-family: 'Noto Sans JP', sans-serif;
  color: var(--text);
  background: var(--sky-lighter);
  margin: 0;
}

.column-header {
  background: var(--white);
  border-bottom: 1px solid var(--border);
  padding: 16px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.column-header a.logo-link { display: block; }

.column-header .header-cta {
  background: var(--teal);
  color: white;
  text-decoration: none;
  padding: 8px 18px;
  border-radius: 8px;
  font-weight: 700;
  font-size: 14px;
}

.column-wrap {
  max-width: 860px;
  margin: 0 auto;
  padding: 32px 20px 80px;
}

.column-breadcrumb {
  font-size: 13px;
  color: var(--subtext);
  margin-bottom: 20px;
}

.column-breadcrumb a { color: var(--teal-dark); text-decoration: none; }

.column-index-title {
  font-size: 28px;
  font-weight: 900;
  color: var(--navy);
  margin-bottom: 24px;
}

.column-card-list {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.column-card {
  background: var(--white);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 20px 24px;
  text-decoration: none;
  color: inherit;
  display: block;
}

.column-card:hover { border-color: var(--teal); }

.column-card .cat {
  display: inline-block;
  background: var(--sky-light);
  color: var(--teal-dark);
  font-size: 12px;
  font-weight: 700;
  padding: 3px 10px;
  border-radius: 999px;
  margin-bottom: 8px;
}

.column-card h2 {
  font-size: 19px;
  color: var(--navy);
  margin: 0 0 8px;
}

.column-card p {
  font-size: 14px;
  color: var(--subtext);
  line-height: 1.7;
  margin: 0 0 8px;
}

.column-card .meta {
  font-size: 12px;
  color: var(--subtext);
}

.column-empty {
  color: var(--subtext);
  font-size: 14px;
}

/* 記事詳細 */
.article-preview-badge {
  background: #FEF3C7;
  color: #92400E;
  font-size: 13px;
  font-weight: 700;
  padding: 8px 14px;
  border-radius: 8px;
  margin-bottom: 20px;
}

.article-cat {
  display: inline-block;
  background: var(--sky-light);
  color: var(--teal-dark);
  font-size: 12px;
  font-weight: 700;
  padding: 3px 10px;
  border-radius: 999px;
  margin-bottom: 12px;
}

.article-title {
  font-size: 30px;
  font-weight: 900;
  color: var(--navy);
  line-height: 1.4;
  margin: 0 0 12px;
}

.article-meta {
  font-size: 13px;
  color: var(--subtext);
  margin-bottom: 28px;
}

.article-body {
  font-size: 16px;
  line-height: 1.9;
  color: var(--text);
}

.article-body h2 {
  font-size: 22px;
  color: var(--navy);
  margin: 40px 0 16px;
  padding-top: 8px;
  border-top: 3px solid var(--sky-light);
}

.article-body h3 {
  font-size: 18px;
  color: var(--navy);
  margin: 28px 0 12px;
}

.article-body p { margin: 0 0 18px; }
.article-body ul, .article-body ol { margin: 0 0 18px; padding-left: 1.4em; }
.article-body li { margin-bottom: 6px; }

.article-body blockquote {
  border-left: 4px solid var(--teal);
  background: var(--sky-lighter);
  padding: 14px 18px;
  margin: 0 0 18px;
  color: var(--subtext);
}

.author-box {
  display: flex;
  gap: 16px;
  background: var(--white);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 20px;
  margin-top: 48px;
}

.author-box .author-name {
  font-weight: 700;
  color: var(--navy);
  margin-bottom: 6px;
}

.author-box .author-bio {
  font-size: 14px;
  color: var(--subtext);
  line-height: 1.8;
}

/* CTA */
.column-cta {
  margin-top: 40px;
  background: var(--navy);
  color: white;
  border-radius: 14px;
  padding: 32px 28px;
  text-align: center;
}

.column-cta h3 {
  font-size: 20px;
  margin: 0 0 10px;
}

.column-cta p {
  font-size: 14px;
  color: rgba(255,255,255,0.8);
  margin: 0 0 20px;
}

.column-cta a.btn-primary {
  display: inline-block;
  background: var(--teal);
  color: white;
  text-decoration: none;
  font-weight: 700;
  padding: 14px 28px;
  border-radius: 10px;
}

.column-cta a.btn-primary:hover { background: var(--teal-dark); }

@media (max-width: 600px) {
  .article-title { font-size: 24px; }
  .column-wrap { padding: 20px 16px 60px; }
}