@import url("https://fonts.googleapis.com/css2?family=Shippori+Mincho:wght@500;600&family=Zen+Kaku+Gothic+New:wght@400;500;700&display=swap");

:root {
  --brand-ink: #0f1f2b;
  --brand-ink-soft: #2a3b46;
  --brand-accent: #2f9db0;
  --brand-accent-soft: #66c3d1;
  --brand-legacy: #c98a4b;
  --brand-bg: #f3f6f8;
  --brand-paper: rgba(255, 255, 255, 0.92);
  --brand-line: #e2e8ee;
  --brand-shadow: rgba(12, 26, 36, 0.12);
}

:root {
  --md-primary-fg-color: var(--brand-ink);
  --md-accent-fg-color: var(--brand-accent);
  --md-default-bg-color: var(--brand-bg);
  --md-default-fg-color: var(--brand-ink);
  --md-default-fg-color--light: #5c6f78;
  --md-default-fg-color--lightest: #cfd8df;
}

html,
body {
  font-family: "Zen Kaku Gothic New", "Hiragino Kaku Gothic ProN", "Noto Sans JP", sans-serif;
  color: var(--brand-ink);
  background-color: var(--brand-bg);
  background-image:
    radial-gradient(1200px 600px at 10% 0%, rgba(102, 195, 209, 0.18), transparent 55%),
    radial-gradient(900px 420px at 90% 10%, rgba(201, 138, 75, 0.12), transparent 60%),
    repeating-linear-gradient(90deg, rgba(15, 31, 43, 0.02) 0, rgba(15, 31, 43, 0.02) 1px, transparent 1px, transparent 80px);
}

.md-header {
  background: linear-gradient(90deg, #0f1f2b 0%, #143341 55%, #1f4a54 100%);
  box-shadow: 0 6px 18px rgba(10, 20, 28, 0.25);
  border-bottom: 1px solid rgba(255, 255, 255, 0.12);
}

.md-header__title,
.md-header__title .md-header__topic {
  font-family: "Shippori Mincho", "Hiragino Mincho ProN", serif;
  letter-spacing: 0.03em;
}

.md-tabs {
  background: rgba(15, 31, 43, 0.92);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid rgba(255, 255, 255, 0.06);
}

.md-tabs__link {
  color: rgba(255, 255, 255, 0.7);
  font-weight: 500;
}

.md-tabs__link--active,
.md-tabs__link:hover {
  color: #ffffff;
}

.md-main {
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.55) 0%, rgba(243, 246, 248, 0.9) 60%, rgba(237, 242, 246, 1) 100%);
}

.md-content__inner {
  background: var(--brand-paper);
  border-radius: 20px;
  padding: 26px 26px 42px;
  border: 1px solid var(--brand-line);
  box-shadow: 0 18px 40px var(--brand-shadow);
  backdrop-filter: blur(10px);
}

.md-content__inner h1,
.md-content__inner h2,
.md-content__inner h3 {
  font-family: "Shippori Mincho", "Hiragino Mincho ProN", serif;
  color: var(--brand-ink);
}

.md-content__inner h1 {
  font-size: 2.15rem;
  letter-spacing: 0.02em;
}

.md-content__inner h2 {
  margin-top: 2rem;
  font-size: 1.55rem;
}

.md-content__inner p {
  line-height: 1.85;
}

.md-content__inner ul,
.md-content__inner ol {
  margin: 0.9em 0 1.4em 1.6em;
  padding-left: 1.1em;
  line-height: 1.75;
}

.md-content__inner li {
  margin: 0.45em 0;
}

.md-content__inner li::marker {
  color: var(--brand-accent);
  font-weight: 600;
}

.md-content__inner blockquote {
  border-left: 4px solid var(--brand-accent-soft);
  background: rgba(47, 157, 176, 0.08);
  padding: 12px 16px;
  border-radius: 10px;
}

.hero {
  position: relative;
  padding: 18px 0 10px;
  margin-bottom: 20px;
}

.hero::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: -12px;
  height: 1px;
  background: linear-gradient(90deg, transparent 0%, rgba(201, 138, 75, 0.5) 30%, rgba(47, 157, 176, 0.5) 70%, transparent 100%);
}

.hero-kicker {
  font-size: 0.8rem;
  letter-spacing: 0.24em;
  text-transform: uppercase;
  color: var(--brand-legacy);
  margin: 0 0 6px;
}

.hero-lead {
  margin: 8px 0 12px;
  color: var(--brand-ink-soft);
  font-size: 1.03rem;
}

.hero-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.hero-meta span {
  background: rgba(15, 31, 43, 0.08);
  color: #2a3b46;
  padding: 4px 12px;
  border-radius: 999px;
  font-size: 0.78rem;
  letter-spacing: 0.04em;
  border: 1px solid rgba(47, 157, 176, 0.2);
}

.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 18px;
  margin: 18px 0 30px;
}

.card {
  position: relative;
  border-radius: 18px;
  padding: 18px;
  background: linear-gradient(140deg, rgba(255, 255, 255, 0.95) 0%, rgba(239, 245, 248, 0.9) 100%);
  border: 1px solid rgba(47, 157, 176, 0.18);
  box-shadow: 0 12px 26px rgba(15, 31, 43, 0.12);
  overflow: hidden;
  transform: translateY(0);
  transition: transform 0.25s ease, box-shadow 0.25s ease;
  animation: floatUp 0.6s ease both;
}

.card:nth-child(2) { animation-delay: 0.05s; }
.card:nth-child(3) { animation-delay: 0.1s; }
.card:nth-child(4) { animation-delay: 0.15s; }

.card::before {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: 18px;
  border: 1px solid transparent;
  background: linear-gradient(120deg, rgba(47, 157, 176, 0.35), rgba(201, 138, 75, 0.25)) border-box;
  -webkit-mask: linear-gradient(#fff 0 0) padding-box, linear-gradient(#fff 0 0);
  -webkit-mask-composite: xor;
  mask-composite: exclude;
  pointer-events: none;
}

.card:hover {
  transform: translateY(-5px);
  box-shadow: 0 20px 32px rgba(15, 31, 43, 0.18);
}

.card-title {
  font-size: 1.08rem;
  font-weight: 700;
  margin-bottom: 6px;
}

.card-count {
  font-size: 0.88rem;
  color: var(--brand-ink-soft);
  margin-bottom: 6px;
}

.card-desc {
  font-size: 0.9rem;
  color: var(--brand-ink-soft);
  margin-bottom: 12px;
}

.card-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-weight: 600;
  text-decoration: none;
  color: var(--brand-accent);
}

.card-link::after {
  content: "→";
  transition: transform 0.2s ease;
}

.card-link:hover::after {
  transform: translateX(4px);
}

.details-list details {
  border: 1px solid var(--brand-line);
  border-radius: 12px;
  padding: 12px 16px;
  margin: 12px 0;
  background: rgba(255, 255, 255, 0.9);
  box-shadow: 0 6px 16px rgba(15, 31, 43, 0.08);
}

.details-list summary {
  cursor: pointer;
  font-weight: 600;
  list-style: none;
  color: var(--brand-ink);
}

.details-list summary::-webkit-details-marker {
  display: none;
}

.details-list summary::before {
  content: "▸ ";
  color: var(--brand-accent);
}

.details-list details[open] summary::before {
  content: "▾ ";
}

@keyframes floatUp {
  from {
    opacity: 0;
    transform: translateY(12px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@media (max-width: 720px) {
  .md-content__inner {
    padding: 20px 16px 32px;
  }

  .hero-meta {
    gap: 6px;
  }

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

/* Hide footer to avoid it cutting through long side navigation */
.md-footer {
  display: none;
}