:root {
  color-scheme: light;
  --bg: #f7f8fb;
  --surface: #ffffff;
  --text: #1f2933;
  --muted: #5d6978;
  --line: #dce1e8;
  --accent: #0f766e;
  --accent-strong: #0b5f59;
  --accent-soft: #e4f4f1;
  --link: #075985;
  --shadow: 0 12px 30px rgba(31, 41, 51, 0.08);
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: "Segoe UI", system-ui, -apple-system, BlinkMacSystemFont, Arial, sans-serif;
  line-height: 1.6;
}

a {
  color: var(--link);
  text-decoration-thickness: 1px;
  text-underline-offset: 0.18em;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  background: rgba(247, 248, 251, 0.94);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(14px);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  width: min(1120px, calc(100% - 36px));
  margin: 0 auto;
  padding: 15px 0;
}

.brand {
  color: var(--text);
  font-weight: 700;
  text-decoration: none;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 6px;
  flex-wrap: wrap;
  justify-content: flex-end;
}

.nav-links a {
  color: var(--muted);
  padding: 7px 10px;
  border-radius: 6px;
  text-decoration: none;
}

.nav-links a:hover,
.nav-links a[aria-current="page"] {
  color: var(--accent-strong);
  background: var(--accent-soft);
}

.nav-links .lang-switch {
  border: 1px solid var(--line);
  color: var(--text);
  font-weight: 650;
}

.hero,
.page {
  width: min(1120px, calc(100% - 36px));
  margin: 0 auto;
}

.hero {
  padding: 82px 0 44px;
}

.eyebrow {
  color: var(--accent-strong);
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

h1,
h2,
h3 {
  line-height: 1.2;
  margin: 0;
}

.hero h1 {
  max-width: 860px;
  margin-top: 14px;
  font-size: clamp(2.1rem, 4.5vw, 4.25rem);
}

.hero p,
.page-heading p {
  max-width: 760px;
  color: var(--muted);
  font-size: 1.05rem;
}

.actions {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  margin-top: 28px;
}

.button {
  display: inline-flex;
  align-items: center;
  min-height: 42px;
  padding: 9px 15px;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: var(--surface);
  color: var(--text);
  font-weight: 650;
  text-decoration: none;
}

.button.primary {
  border-color: var(--accent);
  background: var(--accent);
  color: #ffffff;
}

.summary-grid,
.content-band,
.page-heading,
.archive-list,
.prose {
  width: min(1120px, calc(100% - 36px));
  margin: 0 auto;
}

.summary-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 18px;
  padding: 24px 0 36px;
}

.summary-card {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 22px;
  box-shadow: var(--shadow);
}

.summary-number {
  color: var(--accent-strong);
  font-size: 2rem;
  font-weight: 800;
}

.summary-card h2 {
  margin-top: 7px;
  font-size: 1.05rem;
}

.summary-card p {
  color: var(--muted);
  margin-bottom: 0;
}

.content-band {
  padding: 38px 0 70px;
}

.content-band h2 {
  margin-bottom: 18px;
}

.highlight-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

.highlight-card {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 20px;
  box-shadow: var(--shadow);
}

.highlight-card h3 {
  color: var(--accent-strong);
  font-size: 1.02rem;
}

.highlight-card p {
  color: var(--muted);
  margin-bottom: 0;
  margin-top: 8px;
}

.band-cta {
  margin-top: 22px;
  font-weight: 650;
}

.research-group {
  width: min(1120px, calc(100% - 36px));
  margin: 0 auto;
  padding: 30px 0;
  border-bottom: 1px solid var(--line);
}

.research-section-title {
  width: min(1120px, calc(100% - 36px));
  margin: 10px auto 0;
  padding: 28px 0 8px;
}

.research-section-title h2 {
  font-size: 1.65rem;
  margin-top: 8px;
}

.research-section-title p {
  max-width: 760px;
  color: var(--muted);
  margin: 8px 0 0;
}

.impact-title {
  margin-top: 34px;
  border-top: 1px solid var(--line);
}

.research-group:last-of-type {
  border-bottom: none;
}

.research-group h2 {
  font-size: 1.5rem;
  margin-bottom: 12px;
}

.research-group > p {
  max-width: 820px;
  color: var(--muted);
  margin: 0 0 18px;
}

.key-works {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 14px;
}

.work-item {
  display: flex;
  flex-direction: column;
  gap: 3px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-left: 3px solid var(--accent);
  border-radius: 8px;
  padding: 14px 18px;
  box-shadow: var(--shadow);
}

.work-title {
  font-weight: 650;
  color: var(--text);
}

.work-meta {
  color: var(--accent-strong);
  font-size: 0.88rem;
  font-weight: 600;
}

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

.work-links {
  color: var(--muted);
  font-size: 0.94rem;
  margin-top: 5px;
}

.work-links a {
  font-weight: 600;
}

.site-footer a {
  color: var(--link);
  text-decoration: none;
}

.site-footer a:hover {
  text-decoration: underline;
}

.tag-list {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.tag-list span {
  border: 1px solid #b8d9d4;
  border-radius: 999px;
  background: #eef8f6;
  color: #174f4a;
  padding: 6px 11px;
  font-size: 0.94rem;
}

.page {
  padding-bottom: 70px;
}

.page-heading {
  padding: 58px 0 24px;
}

.page-heading h1 {
  margin-top: 10px;
  font-size: clamp(2rem, 3.5vw, 3rem);
}

.archive-section,
.prose-section {
  margin-top: 24px;
}

.archive-section h2,
.prose h2 {
  padding-bottom: 10px;
  border-bottom: 1px solid var(--line);
  font-size: 1.45rem;
}

.archive-section ol {
  margin: 16px 0 0;
  padding-left: 26px;
}

.archive-section li {
  margin: 0 0 14px;
  padding-left: 4px;
}

.archive-section li,
.prose li,
.work-desc {
  max-width: 980px;
}

.archive-section li::marker {
  color: var(--muted);
}

.prose {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 26px;
  box-shadow: var(--shadow);
}

.prose h2:not(:first-child),
.prose h3:not(:first-child) {
  margin-top: 28px;
}

.prose h3 {
  color: var(--accent-strong);
  font-size: 1.05rem;
}

.prose p,
.prose li {
  color: var(--muted);
}

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

.site-footer {
  border-top: 1px solid var(--line);
  color: var(--muted);
  padding: 24px 18px;
  text-align: center;
}

@media (max-width: 980px) {
  .summary-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 760px) {
  .nav {
    align-items: flex-start;
    flex-direction: column;
    gap: 8px;
  }

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

  .hero {
    padding-top: 54px;
  }

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

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

  .prose {
    padding: 20px;
  }
}