:root {
  --bg: #f7f9fc;
  --surface: #ffffff;
  --surface-alt: #eef5f8;
  --ink: #101828;
  --muted: #5c687a;
  --muted-2: #798399;
  --line: #d9e3ea;
  --primary: #0f6b7a;
  --primary-dark: #084654;
  --primary-soft: #d8f3f6;
  --accent: #14a8c4;
  --accent-2: #65d3e8;
  --shadow: 0 22px 70px rgba(16, 24, 40, 0.10);
  --radius: 24px;
  --max: 1180px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  background: var(--bg);
  color: var(--ink);
  line-height: 1.65;
}

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

a {
  color: inherit;
}

code,
pre {
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", monospace;
}

.container {
  width: min(100% - 40px, var(--max));
  margin-inline: auto;
}

.narrow {
  width: min(100% - 40px, 860px);
}

.skip-link {
  position: absolute;
  left: -999px;
  top: 12px;
  z-index: 10;
  background: var(--ink);
  color: #fff;
  padding: 10px 14px;
  border-radius: 10px;
}

.skip-link:focus {
  left: 12px;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(247, 249, 252, 0.86);
  border-bottom: 1px solid rgba(217, 227, 234, 0.72);
  backdrop-filter: blur(18px);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 28px;
  padding: 14px 0;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  font-weight: 800;
  letter-spacing: -0.02em;
}

.brand-mark {
  display: grid;
  place-items: center;
  width: 42px;
  height: 42px;
  border-radius: 13px;
  background: linear-gradient(135deg, var(--primary-dark), var(--accent));
  color: #fff;
  font-size: 13px;
  letter-spacing: 0.04em;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 22px;
  color: var(--muted);
  font-size: 14px;
  font-weight: 650;
}

.nav-links a {
  text-decoration: none;
}

.nav-links a:hover,
.nav-links a:focus-visible {
  color: var(--primary);
}

.nav-toggle {
  display: none;
  border: 0;
  background: transparent;
  padding: 8px;
}

.nav-toggle span {
  display: block;
  width: 24px;
  height: 2px;
  margin: 5px 0;
  background: var(--ink);
  border-radius: 999px;
}

.section {
  padding: 96px 0;
}

.section-tight {
  padding: 72px 0 86px;
}

.alt {
  background: linear-gradient(180deg, #eef6f8 0%, #f8fbfc 100%);
  border-block: 1px solid rgba(217, 227, 234, 0.7);
}

.hero {
  position: relative;
  overflow: hidden;
  background:
    radial-gradient(circle at 15% 10%, rgba(20, 168, 196, 0.20), transparent 32%),
    radial-gradient(circle at 88% 0%, rgba(101, 211, 232, 0.25), transparent 30%);
}

.hero-bg {
  position: absolute;
  inset: 0;
  opacity: 0.45;
  background-image:
    linear-gradient(rgba(15, 107, 122, 0.07) 1px, transparent 1px),
    linear-gradient(90deg, rgba(15, 107, 122, 0.07) 1px, transparent 1px);
  background-size: 44px 44px;
  mask-image: linear-gradient(to bottom, #000, transparent 82%);
}

.hero-grid {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1.02fr) minmax(390px, 0.98fr);
  gap: 50px;
  align-items: center;
}

.eyebrow,
.section-kicker {
  color: var(--primary);
  text-transform: uppercase;
  letter-spacing: 0.14em;
  font-size: 12px;
  font-weight: 800;
  margin: 0 0 14px;
}

h1,
h2,
h3 {
  line-height: 1.12;
  letter-spacing: -0.04em;
  margin: 0;
}

h1 {
  font-size: clamp(42px, 6vw, 72px);
  max-width: 960px;
}

h2 {
  font-size: clamp(32px, 4vw, 48px);
}

h3 {
  font-size: 22px;
}

p {
  margin: 0;
}

.authors {
  margin-top: 22px;
  color: var(--muted);
  font-weight: 700;
}

.authors span {
  display: block;
  margin-top: 4px;
  color: var(--muted-2);
  font-weight: 500;
  font-size: 14px;
}

.lede {
  margin-top: 24px;
  font-size: 20px;
  color: var(--muted);
  max-width: 720px;
}

.cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 34px;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 46px;
  padding: 11px 18px;
  border-radius: 999px;
  background: var(--ink);
  color: #fff;
  text-decoration: none;
  font-weight: 800;
  box-shadow: 0 10px 30px rgba(16, 24, 40, 0.18);
}

.button-secondary {
  background: #fff;
  color: var(--ink);
  border: 1px solid var(--line);
  box-shadow: none;
}

.button-disabled {
  cursor: not-allowed;
  opacity: 0.82;
}

.text-link {
  color: var(--primary-dark);
  font-weight: 800;
  text-decoration: none;
  border-bottom: 1px solid currentColor;
}

.text-link:hover,
.text-link:focus-visible {
  color: var(--ink);
}

.stat-strip {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
  margin: 34px 0 0;
}

.stat-strip div,
.metric-card,
.problem-card,
.feature-card,
.card,
.equation-card,
.notice,
.release-item {
  border: 1px solid rgba(217, 227, 234, 0.95);
  background: rgba(255, 255, 255, 0.86);
  border-radius: var(--radius);
}

.stat-strip div {
  padding: 15px 16px;
}

.stat-strip dt {
  color: var(--muted-2);
  font-size: 12px;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

.stat-strip dd {
  margin: 3px 0 0;
  font-weight: 850;
}

.card {
  box-shadow: var(--shadow);
  overflow: hidden;
}

.hero-figure {
  background: #fff;
}

figcaption {
  padding: 16px 18px 18px;
  color: var(--muted);
  font-size: 14px;
  line-height: 1.5;
  border-top: 1px solid rgba(217, 227, 234, 0.8);
}

.section-heading {
  margin-bottom: 34px;
}

.section-heading.split {
  display: grid;
  grid-template-columns: minmax(0, 0.88fr) minmax(280px, 0.62fr);
  gap: 38px;
  align-items: end;
}

.section-summary {
  color: var(--muted);
  font-size: 18px;
}

.narrow > p:not(.section-kicker) + p {
  margin-top: 18px;
}

.narrow h2 + p,
.section-heading h2 + p {
  margin-top: 18px;
}

.problem-grid,
.feature-grid,
.dataset-grid,
.table-grid,
.two-column {
  display: grid;
  gap: 18px;
}

.problem-grid {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.problem-card {
  padding: 26px;
}

.problem-card p,
.feature-card p,
.text-card p,
.release-item p,
.equation-card p,
.notice,
.table-note {
  color: var(--muted);
}

.problem-card p,
.feature-card p,
.text-card p {
  margin-top: 14px;
}

.accent-card {
  background: linear-gradient(135deg, var(--primary-dark), var(--primary));
  color: #fff;
  border: 0;
}

.accent-card p {
  color: rgba(255, 255, 255, 0.82);
}

.wide-figure {
  background: #fff;
}

.figure-offset {
  margin-top: 32px;
}

.feature-grid {
  grid-template-columns: repeat(4, minmax(0, 1fr));
  margin-top: 22px;
}

.feature-card {
  padding: 24px;
  background: #fff;
}

.feature-index {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  margin-bottom: 18px;
  border-radius: 13px;
  background: var(--primary-soft);
  color: var(--primary-dark);
  font-weight: 900;
  font-size: 13px;
}

.equation-card {
  margin-top: 24px;
  padding: 26px;
  background: linear-gradient(135deg, #ffffff 0%, #effafe 100%);
}

.equation-card code {
  display: inline-block;
  margin: 16px 0 12px;
  padding: 12px 14px;
  border-radius: 12px;
  background: #0b1020;
  color: #d6f7ff;
  overflow-wrap: anywhere;
}

.dataset-grid {
  grid-template-columns: repeat(4, minmax(0, 1fr));
}

.metric-card {
  padding: 26px;
  background: #fff;
}

.metric-card strong {
  display: block;
  color: var(--primary-dark);
  font-size: 38px;
  line-height: 1;
  letter-spacing: -0.05em;
}

.metric-card span {
  display: block;
  margin-top: 12px;
  color: var(--muted);
  font-weight: 650;
}

.two-column {
  grid-template-columns: repeat(2, minmax(0, 1fr));
  margin-top: 18px;
}

.text-card {
  padding: 26px;
}

.notice {
  margin-top: 18px;
  padding: 18px 20px;
  background: #fff8e6;
  border-color: #f4d794;
}

.table-grid {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.table-card {
  background: #fff;
  padding: 24px;
}

.table-scroll {
  margin-top: 18px;
  overflow-x: auto;
  border-radius: 16px;
  border: 1px solid var(--line);
}

table {
  width: 100%;
  border-collapse: collapse;
  min-width: 650px;
  font-size: 14px;
}

th,
td {
  padding: 12px 13px;
  text-align: left;
  border-bottom: 1px solid var(--line);
}

th {
  background: #f0f7f9;
  color: var(--primary-dark);
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

tbody tr:last-child td {
  border-bottom: 0;
}

.table-note {
  margin-top: 14px;
  font-size: 14px;
}

.release-list {
  display: grid;
  gap: 14px;
  margin-top: 28px;
}

.release-item {
  display: flex;
  justify-content: space-between;
  gap: 18px;
  align-items: center;
  padding: 22px;
  background: #fff;
}

.release-item h3 {
  margin-bottom: 8px;
}

.pill {
  flex: 0 0 auto;
  padding: 7px 12px;
  border-radius: 999px;
  font-weight: 800;
  font-size: 12px;
}

.pill.muted {
  background: #eef2f6;
  color: var(--muted);
}

.code-card {
  position: relative;
  margin-top: 22px;
  overflow: hidden;
  border-radius: var(--radius);
  border: 1px solid rgba(217, 227, 234, 0.95);
  background: #0b1020;
  box-shadow: var(--shadow);
}

pre {
  margin: 0;
  padding: 24px;
  overflow-x: auto;
  color: #d8f7ff;
  line-height: 1.55;
}

.copy-button {
  position: absolute;
  top: 14px;
  right: 14px;
  border: 1px solid rgba(255, 255, 255, 0.18);
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.1);
  color: #fff;
  padding: 8px 12px;
  font-weight: 800;
  cursor: pointer;
}

.copy-button:hover,
.copy-button:focus-visible {
  background: rgba(255, 255, 255, 0.18);
}

.site-footer {
  padding: 30px 0;
  background: #0b1020;
  color: rgba(255, 255, 255, 0.78);
}

.footer-grid {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
}

.footer-grid a {
  color: #fff;
  text-decoration: none;
  font-weight: 800;
}

@media (max-width: 1050px) {
  .hero-grid,
  .section-heading.split,
  .table-grid {
    grid-template-columns: 1fr;
  }

  .feature-grid,
  .dataset-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 820px) {
  .nav-toggle {
    display: block;
  }

  .nav-links {
    position: absolute;
    top: 72px;
    left: 20px;
    right: 20px;
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 12px;
    background: #fff;
    border: 1px solid var(--line);
    border-radius: 18px;
    box-shadow: var(--shadow);
  }

  .nav-links.is-open {
    display: flex;
  }

  .nav-links a {
    padding: 11px 12px;
  }

  .problem-grid,
  .feature-grid,
  .dataset-grid,
  .two-column,
  .stat-strip {
    grid-template-columns: 1fr;
  }

  .section {
    padding: 72px 0;
  }

  .section-tight {
    padding: 56px 0 70px;
  }

  .release-item,
  .footer-grid {
    flex-direction: column;
    align-items: flex-start;
  }
}

@media (max-width: 540px) {
  .container,
  .narrow {
    width: min(100% - 28px, var(--max));
  }

  .cta-row,
  .button {
    width: 100%;
  }

  h1 {
    font-size: 38px;
  }

  .lede {
    font-size: 18px;
  }

  pre {
    padding: 58px 18px 20px;
    font-size: 12px;
  }
}