:root {
  --bg: #f3f1eb;
  --surface: rgba(255, 255, 255, 0.94);
  --surface-strong: #ffffff;
  --surface-muted: #f7f4ee;
  --text: #1c2a39;
  --muted: #5f6f7f;
  --border: #d7dde4;
  --accent: #123b63;
  --accent-soft: #e5eef6;
  --accent-warm: #8f6a3a;
  --shadow: 0 18px 40px rgba(20, 34, 53, 0.08);
  --max-width: 1100px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--text);
  font-family: "Noto Sans JP", "Hiragino Sans", "Yu Gothic", sans-serif;
  line-height: 1.8;
  background:
    linear-gradient(180deg, rgba(18, 59, 99, 0.08), rgba(18, 59, 99, 0) 280px),
    radial-gradient(circle at top left, rgba(143, 106, 58, 0.14), transparent 36%),
    var(--bg);
}

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

a:hover {
  text-decoration: underline;
}

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

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  backdrop-filter: blur(14px);
  background: rgba(243, 241, 235, 0.9);
  border-bottom: 1px solid rgba(18, 59, 99, 0.12);
}

.header-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 16px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.site-brand {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.site-brand a {
  text-decoration: none;
}

.site-title {
  font-family: "Noto Serif JP", "Yu Mincho", serif;
  font-size: 1.2rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  color: var(--accent);
}

.site-subtitle {
  font-size: 0.88rem;
  color: var(--muted);
}

.site-nav {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 10px;
}

.site-nav a {
  padding: 8px 14px;
  border: 1px solid transparent;
  border-radius: 999px;
  font-size: 0.95rem;
  transition: background-color 0.2s ease, border-color 0.2s ease;
}

.site-nav a:hover,
.site-nav a.current {
  background: var(--accent-soft);
  border-color: rgba(18, 59, 99, 0.16);
  text-decoration: none;
}

.page-shell {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 40px 24px 72px;
}

.hero {
  padding: 48px;
  border-radius: 28px;
  color: #f8fbff;
  background:
    linear-gradient(135deg, rgba(7, 29, 49, 0.9), rgba(18, 59, 99, 0.78)),
    linear-gradient(180deg, rgba(255, 255, 255, 0.04), rgba(255, 255, 255, 0));
  box-shadow: var(--shadow);
}

.hero-simple {
  padding: 36px 40px;
  border-radius: 24px;
  background: linear-gradient(135deg, rgba(18, 59, 99, 0.1), rgba(143, 106, 58, 0.1));
  border: 1px solid rgba(18, 59, 99, 0.08);
}

.hero h1,
.hero-simple h1 {
  margin: 0;
  font-family: "Noto Serif JP", "Yu Mincho", serif;
  font-size: clamp(2rem, 4vw, 3.2rem);
  line-height: 1.3;
}

.hero .meta,
.hero-simple .meta {
  margin-top: 14px;
  color: inherit;
  opacity: 0.82;
  font-size: 0.95rem;
}

.hero-image {
  margin-top: 28px;
  border-radius: 22px;
  overflow: hidden;
  box-shadow: 0 22px 50px rgba(0, 0, 0, 0.24);
}

.content-grid {
  margin-top: 28px;
  display: grid;
  gap: 24px;
  grid-template-columns: 1.15fr 0.85fr;
  align-items: start;
}

.card,
.content-panel,
.media-panel {
  background: var(--surface);
  border: 1px solid rgba(18, 59, 99, 0.08);
  border-radius: 24px;
  box-shadow: var(--shadow);
}

.card,
.content-panel {
  padding: 32px;
}

.media-panel {
  padding: 24px;
}

.panel-title {
  margin: 0 0 18px;
  font-family: "Noto Serif JP", "Yu Mincho", serif;
  font-size: 1.2rem;
  color: var(--accent);
}

.link-list {
  display: grid;
  gap: 14px;
}

.link-list a {
  display: block;
  padding: 14px 16px;
  border-radius: 16px;
  background: var(--surface-muted);
  border: 1px solid rgba(18, 59, 99, 0.08);
  font-weight: 600;
}

.feature-link {
  display: block;
  overflow: hidden;
  border-radius: 20px;
  background: var(--surface-strong);
  border: 1px solid rgba(18, 59, 99, 0.08);
}

.feature-link img {
  width: 100%;
}

.feature-link span {
  display: block;
  padding: 18px 18px 20px;
  font-weight: 700;
}

.section-card {
  margin-top: 28px;
  padding: 34px;
  background: var(--surface);
  border: 1px solid rgba(18, 59, 99, 0.08);
  border-radius: 24px;
  box-shadow: var(--shadow);
}

.section-card h2,
.section-card h3,
.section-card h4 {
  font-family: "Noto Serif JP", "Yu Mincho", serif;
  color: var(--accent);
}

.section-card h2 {
  margin-top: 0;
  margin-bottom: 18px;
  font-size: 1.7rem;
}

.section-card h3 {
  margin-top: 32px;
  margin-bottom: 14px;
  font-size: 1.3rem;
}

.section-card h4 {
  margin-top: 22px;
  margin-bottom: 10px;
  font-size: 1.08rem;
}

.section-card p {
  margin: 0 0 1em;
}

.section-card ul {
  padding-left: 1.4em;
}

.section-card table {
  width: 100%;
  border-collapse: collapse;
  background: var(--surface-strong);
  overflow: hidden;
  border-radius: 18px;
}

.section-card td,
.section-card th {
  padding: 14px 16px;
  border: 1px solid rgba(18, 59, 99, 0.14);
  vertical-align: top;
}

.section-card tr:nth-child(even) {
  background: rgba(18, 59, 99, 0.04);
}

.section-card li + li {
  margin-top: 0.5em;
}

.image-frame {
  margin: 22px auto;
  padding: 14px;
  background: var(--surface-strong);
  border: 1px solid rgba(18, 59, 99, 0.08);
  border-radius: 22px;
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.7);
}

.image-frame img {
  margin: 0 auto;
  border-radius: 14px;
}

.year-block {
  margin-top: 30px;
  padding: 28px;
  border-radius: 20px;
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.72), rgba(247, 244, 238, 0.9));
  border: 1px solid rgba(18, 59, 99, 0.08);
}

details.year-archive {
  margin-top: 24px;
  padding: 24px 28px;
  border-radius: 20px;
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.72), rgba(247, 244, 238, 0.9));
  border: 1px solid rgba(18, 59, 99, 0.08);
}

details.year-archive summary {
  cursor: pointer;
  font-family: "Noto Serif JP", "Yu Mincho", serif;
  font-size: 1.35rem;
  color: var(--accent);
}

.back-link {
  margin-top: 28px;
  text-align: center;
}

.back-link a {
  display: inline-block;
  min-width: 180px;
  padding: 14px 22px;
  border-radius: 999px;
  background: var(--accent);
  color: #ffffff;
  font-weight: 700;
  letter-spacing: 0.04em;
}

.back-link a:hover {
  text-decoration: none;
  background: #0f3153;
}

.site-footer {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px 36px;
  color: var(--muted);
  font-size: 0.92rem;
}

@media (max-width: 900px) {
  .header-inner {
    flex-direction: column;
    align-items: flex-start;
  }

  .site-nav {
    justify-content: flex-start;
  }

  .hero,
  .hero-simple,
  .card,
  .content-panel,
  .section-card {
    padding: 24px;
  }

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

@media (max-width: 600px) {
  .page-shell {
    padding: 24px 16px 56px;
  }

  .header-inner,
  .site-footer {
    padding-left: 16px;
    padding-right: 16px;
  }

  .site-nav {
    gap: 8px;
  }

  .site-nav a {
    padding: 7px 12px;
    font-size: 0.9rem;
  }

  .hero h1,
  .hero-simple h1 {
    font-size: 1.8rem;
  }

  .year-block,
  details.year-archive {
    padding: 20px;
  }
}