:root {
  --bg: #fbfaf7;
  --panel: #ffffff;
  --panel-soft: #f4f0e8;
  --text: #20242b;
  --muted: #666f7c;
  --link: #1d5f8a;
  --accent: #0f766e;
  --border: #ddd6ca;

  --radius: 8px;
  --shadow: 0 10px 28px rgba(31, 36, 43, 0.08);
  --maxw: 1000px;
  --measure: 720px;
}

* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body {
  background: var(--bg);
  color: var(--text);
  font: 16px/1.6 system-ui, -apple-system, Segoe UI, Roboto, Helvetica, Arial, sans-serif;
}

a {
  color: var(--link);
  text-underline-offset: 0.18em;
}

a:hover { color: #174b6d; }

.container {
  width: 100%;
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 20px;
}

.hero {
  display: flex;
  justify-content: center;
  margin: 24px 0 12px;
}
.hero-card {
  width: 100%;
  max-width: 1200px;
  height: auto;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
}

.skip-link {
  position: absolute;
  left: -9999px;
}
.skip-link:focus {
  left: 8px;
  top: 8px;
  background: var(--accent);
  color: #fff;
  padding: 8px 12px;
  border-radius: 6px;
  z-index: 20;
}

.site-header {
  position: sticky;
  top: 0;
  backdrop-filter: blur(10px);
  background: color-mix(in oklab, var(--bg) 92%, transparent);
  border-bottom: 1px solid var(--border);
  z-index: 10;
}
.site-header .container {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 20px;
}
.site-title {
  font-size: 1.1rem;
  line-height: 1.2;
  margin: 16px 0;
  letter-spacing: 0;
}
.nav {
  display: flex;
  flex-wrap: wrap;
  gap: 6px 18px;
  list-style: none;
  padding: 0;
  margin: 14px 0;
}
.nav a {
  color: var(--link);
  text-decoration: none;
  outline: 2px solid transparent;
  outline-offset: 2px;
  font-size: 0.95rem;
}
.nav a:hover, .nav a:focus-visible {
  text-decoration: underline;
  outline: 2px solid var(--accent);
}
.nav a[aria-current="page"] {
  color: var(--text);
  font-weight: 650;
}

.intro {
  max-width: var(--measure);
  margin: 44px 0 16px;
}
.intro h2,
.page-intro h1 {
  margin: 0;
  font-size: clamp(2rem, 5vw, 3.7rem);
  line-height: 1.06;
  letter-spacing: 0;
}
.lede {
  color: #3d4652;
  font-size: 1.18rem;
  line-height: 1.58;
  margin: 18px 0 0;
}
.intro-meta,
.series-kicker {
  color: var(--accent);
  font-size: 0.9rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  margin: 0 0 12px;
  text-transform: uppercase;
}

.author-strip {
  border-block: 1px solid var(--border);
  color: var(--muted);
  display: flex;
  flex-wrap: wrap;
  gap: 8px 12px;
  margin: 24px 0 34px;
  padding: 12px 0;
}
.author-strip strong { color: var(--text); }
.author-strip span + span::before {
  color: #a49a8d;
  content: "/";
  margin: 0 12px;
}

button.report-link {
  color: var(--link);
  border: 1px solid var(--border);
  background: transparent;
  border-radius: 6px;
  padding: 5px 10px;
  cursor: pointer;
}
button.report-link:hover,
button.report-link:focus-visible {
  background: color-mix(in oklab, var(--accent) 10%, transparent);
  outline: 2px solid var(--accent);
}

.section { margin: 44px 0; }
.section h2,
.section h1 { margin: 0 0 12px; }
.section p { max-width: var(--measure); }

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

.projects-grid {
  display: grid;
  grid-template-columns: repeat(1, minmax(0, 1fr));
  gap: 16px;
  margin-top: 12px;
}
@media (min-width: 640px) {
  .projects-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (min-width: 980px) {
  .projects-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); }
}

.card {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 16px;
  box-shadow: var(--shadow);
  display: flex;
  flex-direction: column;
  gap: 8px;
}
.card h3 {
  margin: 0;
  font-size: 1.08rem;
  line-height: 1.3;
}
.card p {
  margin: 0;
  color: #3e4651;
}
.card .meta {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  align-items: center;
  font-size: 0.9rem;
  color: var(--muted);
}
.reports {
  margin-top: 8px;
  font-size: 0.9rem;
}
.report-link {
  color: var(--link);
  text-decoration: none;
}
.report-link:hover { text-decoration: underline; }
.badge {
  display: inline-block;
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 2px 8px;
  font-size: 0.8rem;
  color: var(--muted);
  background: #fbfaf7;
}
.card a {
  color: var(--link);
  text-decoration: none;
}
.card a:hover { text-decoration: underline; }

.page-intro {
  max-width: var(--measure);
  margin: 48px 0 30px;
}

.series-feature {
  background: var(--panel-soft);
  border-block: 1px solid var(--border);
  margin: 30px calc(50% - 50vw);
  padding: 34px max(20px, calc((100vw - var(--maxw)) / 2));
}
.series-feature-inner {
  max-width: var(--maxw);
}
.series-feature h2 {
  font-size: clamp(1.45rem, 3vw, 2.1rem);
  line-height: 1.2;
  margin: 0;
}
.series-feature p {
  color: #3d4652;
  margin: 12px 0 0;
  max-width: var(--measure);
}
.series-list {
  display: grid;
  gap: 12px;
  margin-top: 22px;
}
.series-item {
  align-items: start;
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  display: grid;
  gap: 4px 14px;
  grid-template-columns: auto 1fr;
  padding: 14px;
  text-decoration: none;
}
.series-item:hover,
.series-item:focus-visible {
  border-color: color-mix(in oklab, var(--accent) 48%, var(--border));
  outline: 2px solid transparent;
}
.part-label {
  color: var(--accent);
  font-size: 0.78rem;
  font-weight: 800;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}
.series-item strong {
  color: var(--text);
  line-height: 1.3;
}
.series-item span:last-child {
  color: var(--muted);
  grid-column: 2;
}
.post-list {
  display: grid;
  gap: 14px;
  margin-top: 12px;
  max-width: var(--measure);
}

.ai-use-note {
  border-top: 1px solid var(--border);
  color: var(--muted);
  font-size: 0.95rem;
  line-height: 1.55;
  margin: 36px 0 0;
  max-width: var(--measure);
  padding-top: 16px;
}
.ai-use-note h2 {
  color: var(--text);
  font-size: 1rem;
  margin: 0 0 6px;
}
.ai-use-note p {
  margin: 0;
}

.site-footer {
  margin: 48px 0 24px;
  border-top: 1px solid var(--border);
  padding-top: 16px;
  color: var(--muted);
}
.status {
  margin-top: 8px;
  font-size: 0.95rem;
}

@media (max-width: 720px) {
  .site-header { position: static; }
  .site-header .container {
    align-items: flex-start;
    flex-direction: column;
    gap: 0;
  }
  .site-title { margin-bottom: 0; }
  .nav { margin-top: 8px; }
  .intro { margin-top: 34px; }
  .author-strip { display: block; }
  .author-strip span { display: block; }
  .author-strip span + span::before { content: none; }
  .series-item { grid-template-columns: 1fr; }
  .series-item span:last-child { grid-column: 1; }
}