:root {
  --bg: #f6f4ef;
  --surface: #fffefb;
  --text: #1a1f24;
  --muted: #4a5560;
  --accent: #0d5c63;
  --brand-red: #8b1f2f;
  --accent-soft: #e3f2f3;
  --border: #d9d4c8;
  --shadow: 0 12px 40px rgba(26, 31, 36, 0.08);
  --radius: 12px;
  --font-body: "Noto Sans JP", system-ui, sans-serif;
  --font-display: "IBM Plex Sans", "Noto Sans JP", system-ui, sans-serif;
  /* 旧 52rem（約832px）より広く。必要ならここだけ調整 */
  --layout-max-width: min(76rem, calc(100vw - 2.5rem));
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: var(--font-body);
  font-size: 1.05rem;
  line-height: 1.75;
  color: var(--text);
  background: var(--bg);
  background-image: radial-gradient(
      circle at 12% 18%,
      rgba(13, 92, 99, 0.07),
      transparent 42%
    ),
    radial-gradient(circle at 88% 8%, rgba(26, 31, 36, 0.05), transparent 38%);
}

a {
  color: var(--accent);
  text-decoration-thickness: 1px;
  text-underline-offset: 0.2em;
}

a:hover {
  text-decoration-thickness: 2px;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  border-bottom: 3px solid var(--brand-red);
  background: var(--surface);
  box-shadow: var(--shadow);
}

.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem 1.5rem;
  flex-wrap: wrap;
  max-width: var(--layout-max-width);
  margin: 0 auto;
  padding: 1rem clamp(1rem, 3vw, 2rem);
}

.site-header__main {
  flex: 1 1 auto;
  min-width: min(100%, 14rem);
}

.site-header__banner {
  flex: 0 0 auto;
  margin-left: auto;
}

.site-header__banner-img {
  display: block;
  height: clamp(3.25rem, 12vw, 6.75rem);
  width: auto;
  max-width: min(65vw, 42rem);
  object-fit: contain;
  object-position: right center;
  border-radius: 6px;
  border: 1px solid var(--border);
  background: #2e2e2e;
}

.site-logo {
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 1.35rem;
  letter-spacing: 0.04em;
  color: var(--text);
  text-decoration: none;
}

.site-logo__mark {
  flex-shrink: 0;
  border-radius: 50%;
  border: 2px solid var(--brand-red);
  object-fit: cover;
}

.site-logo__text {
  line-height: 1.35;
  font-size: clamp(0.95rem, 2.1vw, 1.22rem);
}

.site-logo:hover {
  color: var(--brand-red);
}

.site-logo:hover .site-logo__mark {
  border-color: var(--accent);
}

.site-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem 1.25rem;
  margin-top: 0.75rem;
  font-size: 0.95rem;
}

.site-nav a {
  font-weight: 500;
  color: var(--muted);
  text-decoration: none;
}

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

.page-wrap {
  max-width: var(--layout-max-width);
  margin: 0 auto;
  padding: 0 clamp(1rem, 3vw, 2rem);
}

.content {
  padding: 2.25rem 1.5rem 3.5rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  margin-top: 2rem;
  margin-bottom: 2rem;
  box-shadow: var(--shadow);
}

.markdown-body h1 {
  font-family: var(--font-display);
  font-size: clamp(1.35rem, 3vw, 1.85rem);
  line-height: 1.3;
  letter-spacing: -0.02em;
  margin-top: 2.25rem;
}

.markdown-body > h1:first-of-type {
  margin-top: 0;
  font-size: clamp(1.75rem, 4vw, 2.15rem);
}

.markdown-body h2,
.markdown-body h3 {
  font-family: var(--font-display);
  letter-spacing: -0.01em;
  scroll-margin-top: 5rem;
}

.markdown-body h2 {
  margin-top: 2.25rem;
  padding-bottom: 0.35rem;
  border-bottom: 2px solid var(--accent-soft);
  font-size: 1.35rem;
}

.markdown-body h3 {
  margin-top: 1.5rem;
  font-size: 1.12rem;
  color: var(--muted);
}

.markdown-body p {
  margin: 0.85rem 0;
}

.markdown-body ul,
.markdown-body ol {
  padding-left: 1.35rem;
}

.markdown-body li {
  margin: 0.35rem 0;
}

.markdown-body blockquote {
  margin: 1rem 0;
  padding: 0.75rem 1rem;
  border-left: 4px solid var(--accent);
  background: var(--accent-soft);
  color: var(--muted);
}

.markdown-body blockquote p {
  margin: 0;
}

.markdown-body img {
  max-width: 100%;
  height: auto;
  border-radius: 8px;
  border: 1px solid var(--border);
}

.markdown-body .embed-pdf {
  display: block;
  max-width: 100%;
  min-height: min(70vh, 900px);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--surface);
}

.markdown-body .embed-pdf__fallback {
  margin: 0.5rem 0 0;
  font-size: 0.95rem;
  color: var(--muted);
}

.activity-photos {
  margin: 1.25rem 0 0;
}

.activity-photos__row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
  align-items: start;
}

.activity-photos__cell img {
  width: 100%;
  height: auto;
  display: block;
}

.activity-photos__caption {
  margin: 0.85rem 0 0;
  font-size: 0.92rem;
  color: var(--muted);
  text-align: center;
  line-height: 1.65;
}

@media (max-width: 640px) {
  .activity-photos__row {
    grid-template-columns: 1fr;
  }
}

.post-index {
  margin-bottom: 3rem;
}

.post-index h2 {
  font-family: var(--font-display);
  font-size: 1.25rem;
  margin-top: 0;
  margin-bottom: 1rem;
}

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

.post-index__list li {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 0.5rem 1rem;
  padding: 0.6rem 0;
  border-bottom: 1px solid var(--border);
}

.post-index__list a {
  font-weight: 500;
}

.post-index__date {
  font-size: 0.88rem;
  color: var(--muted);
}

.post__header {
  margin-bottom: 1.5rem;
}

.post__title {
  font-family: var(--font-display);
  font-size: clamp(1.5rem, 4vw, 2rem);
  margin: 0;
  line-height: 1.25;
}

.post__meta {
  margin: 0.5rem 0 0;
  font-size: 0.9rem;
  color: var(--muted);
}

.post-list-page h1 {
  font-family: var(--font-display);
  margin-top: 0;
}

.post-list-page__empty {
  color: var(--muted);
}

.post-list-page__empty code {
  font-size: 0.9em;
  padding: 0.1em 0.35em;
  background: var(--accent-soft);
  border-radius: 4px;
}

.site-footer {
  max-width: var(--layout-max-width);
  margin: 0 auto 2.5rem;
  padding: 0 clamp(1rem, 3vw, 2rem);
  font-size: 0.9rem;
  color: var(--muted);
  text-align: center;
}

.site-footer p {
  margin: 0;
}

@media (max-width: 640px) {
  .site-header__banner {
    width: 100%;
    display: flex;
    justify-content: flex-end;
  }

  .content {
    margin-top: 1rem;
    border-radius: 0;
    border-left: none;
    border-right: none;
  }
}