:root {
  --violet-950: #17102d;
  --violet-900: #231846;
  --violet-800: #30205f;
  --violet-700: #443184;
  --violet-600: #5a49a4;
  --violet-500: #7366bd;
  --blue-500: #5ba8d1;
  --blue-300: #9ed8ed;
  --ink: #252238;
  --muted: #68657a;
  --line: #dedbea;
  --wash: #f5f3fa;
  --white: #ffffff;
  --accent: #7558c5;
  --accent-dark: #4c358d;
  --success: #2c7a68;
  --header-height: 96px;
  --side-width: 270px;
  --content-max: 1240px;
  --shadow-soft: 0 16px 45px rgba(36, 24, 70, 0.1);
  --shadow-card: 0 8px 24px rgba(36, 24, 70, 0.08);
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-height) + 28px);
}

body {
  margin: 0;
  color: var(--ink);
  background: var(--white);
  font-family: Inter, ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  font-size: 17px;
  line-height: 1.72;
  -webkit-font-smoothing: antialiased;
}

body::before {
  position: fixed;
  z-index: -1;
  inset: 0;
  content: "";
  pointer-events: none;
  background:
    radial-gradient(circle at 87% 13%, rgba(128, 104, 198, 0.08), transparent 22rem),
    linear-gradient(180deg, rgba(246, 244, 251, 0.7), transparent 28rem);
}

img,
svg {
  display: block;
  max-width: 100%;
}

a {
  color: var(--accent-dark);
  text-decoration-thickness: 0.08em;
  text-underline-offset: 0.18em;
}

a:hover {
  color: var(--violet-700);
}

button,
input,
textarea,
select {
  font: inherit;
}

:focus-visible {
  outline: 3px solid var(--blue-300);
  outline-offset: 4px;
}

.skip-link {
  position: fixed;
  z-index: 1000;
  top: 10px;
  left: 10px;
  padding: 0.55rem 0.85rem;
  color: var(--violet-950);
  background: var(--white);
  border-radius: 6px;
  transform: translateY(-180%);
}

.skip-link:focus {
  transform: translateY(0);
}

.site-header {
  position: sticky;
  z-index: 100;
  top: 0;
  min-height: var(--header-height);
  color: var(--white);
  background: var(--violet-900);
  box-shadow: 0 5px 22px rgba(22, 13, 48, 0.3);
  isolation: isolate;
}

.header-atmosphere,
.site-header::after {
  position: absolute;
  z-index: -1;
  inset: 0;
  content: "";
  pointer-events: none;
}

.header-atmosphere {
  background:
    radial-gradient(ellipse at 4% 22%, rgba(119, 99, 188, 0.98), transparent 31%),
    radial-gradient(ellipse at 37% 115%, rgba(92, 81, 172, 0.9), transparent 43%),
    radial-gradient(ellipse at 86% -20%, rgba(78, 141, 204, 0.62), transparent 38%),
    linear-gradient(105deg, #3f2d75 0%, #39266f 38%, #2d326f 70%, #254b79 100%);
}

.site-header::after {
  opacity: 0.45;
  background-image:
    radial-gradient(circle at 9% 24%, rgba(255, 255, 255, 0.75) 0 1px, transparent 1.4px),
    radial-gradient(circle at 46% 67%, rgba(255, 255, 255, 0.45) 0 1px, transparent 1.5px),
    radial-gradient(circle at 72% 20%, rgba(159, 216, 237, 0.72) 0 1.2px, transparent 1.7px),
    radial-gradient(circle at 91% 70%, rgba(255, 255, 255, 0.5) 0 1px, transparent 1.4px);
  background-size: 170px 96px, 220px 126px, 260px 118px, 190px 104px;
  mix-blend-mode: screen;
}

.header-inner {
  display: flex;
  width: min(100% - 40px, 1540px);
  min-height: var(--header-height);
  margin-inline: auto;
  align-items: stretch;
}

.brand {
  position: relative;
  display: flex;
  width: 365px;
  min-width: 300px;
  padding: 0.7rem 1.5rem 0.7rem 0;
  align-items: center;
  overflow: hidden;
  text-decoration: none;
}

.brand::after {
  position: absolute;
  top: 15%;
  right: 0;
  width: 1px;
  height: 70%;
  content: "";
  background: linear-gradient(transparent, rgba(255, 255, 255, 0.32), transparent);
}

.brand-wordmark {
  display: flex;
  gap: 0.28rem;
  color: var(--white);
  flex-direction: column;
  line-height: 1;
  text-shadow: 0 2px 12px rgba(19, 12, 46, 0.28);
}

.brand-name {
  font-size: 2rem;
  font-weight: 900;
  letter-spacing: 0.12em;
}

.brand-descriptor {
  color: var(--blue-300);
  font-size: 0.69rem;
  font-weight: 800;
  letter-spacing: 0.21em;
  white-space: nowrap;
}

.primary-navigation {
  display: flex;
  min-width: 0;
  margin-left: auto;
  align-items: stretch;
  justify-content: flex-end;
}

.primary-navigation > a {
  position: relative;
  display: inline-flex;
  padding: 0 1.08rem;
  color: rgba(255, 255, 255, 0.86);
  align-items: center;
  justify-content: center;
  font-size: 1.01rem;
  font-weight: 650;
  letter-spacing: 0.005em;
  text-align: center;
  text-decoration: none;
  white-space: nowrap;
  transition: color 160ms ease, background 160ms ease;
}

.primary-navigation > a::after {
  position: absolute;
  right: 1rem;
  bottom: 0;
  left: 1rem;
  height: 4px;
  content: "";
  background: var(--blue-300);
  border-radius: 4px 4px 0 0;
  transform: scaleX(0);
  transition: transform 160ms ease;
}

.primary-navigation > a:hover,
.primary-navigation > a[aria-current="page"] {
  color: var(--white);
  background: rgba(255, 255, 255, 0.075);
}

.primary-navigation > a:hover::after,
.primary-navigation > a[aria-current="page"]::after {
  transform: scaleX(1);
}

.primary-navigation .source-link {
  gap: 0.28rem;
  margin: 1.35rem 0 1.35rem 0.8rem;
  padding: 0 0.95rem;
  color: var(--violet-950);
  background: rgba(255, 255, 255, 0.92);
  border: 1px solid rgba(255, 255, 255, 0.55);
  border-radius: 8px;
}

.primary-navigation .source-link:hover {
  color: var(--violet-950);
  background: var(--white);
}

.primary-navigation .source-link::after {
  display: none;
}

.primary-navigation svg,
.site-footer svg,
main a svg {
  width: 1em;
  height: 1em;
  fill: none;
  stroke: currentColor;
  stroke-linecap: round;
  stroke-linejoin: round;
  stroke-width: 1.8;
}

.nav-toggle {
  display: none;
}

.site-layout {
  display: grid;
  width: min(100%, 1600px);
  min-height: calc(100vh - var(--header-height));
  margin-inline: auto;
  grid-template-columns: var(--side-width) minmax(0, 1fr);
}

.section-navigation {
  border-right: 1px solid var(--line);
  background: rgba(247, 246, 251, 0.88);
}

.section-nav-inner {
  position: sticky;
  top: var(--header-height);
  max-height: calc(100vh - var(--header-height));
  padding: 3.2rem 1.3rem 3rem;
  overflow-y: auto;
}

.section-nav-title {
  margin: 0 0 1.05rem 0.75rem;
  color: var(--violet-700);
  font-size: 0.78rem;
  font-weight: 800;
  letter-spacing: 0.11em;
  text-transform: uppercase;
}

.section-navigation nav {
  display: grid;
  gap: 0.42rem;
}

.section-navigation a {
  display: flex;
  min-height: 48px;
  padding: 0.68rem 0.72rem;
  color: #555167;
  border-left: 3px solid transparent;
  border-radius: 0 8px 8px 0;
  align-items: center;
  justify-content: space-between;
  font-size: 1.03rem;
  font-weight: 600;
  line-height: 1.35;
  text-decoration: none;
  transition: color 150ms ease, border-color 150ms ease, background 150ms ease;
}

.section-navigation a:hover,
.section-navigation a.is-active {
  color: var(--violet-800);
  border-left-color: var(--accent);
  background: rgba(104, 83, 177, 0.1);
}

.section-navigation svg {
  width: 16px;
  height: 16px;
  flex: 0 0 auto;
  fill: none;
  stroke: currentColor;
  stroke-width: 2;
}

.main-content {
  min-width: 0;
}

.content-wrap {
  width: min(100% - 64px, 1050px);
  margin-inline: auto;
  padding: 4.5rem 0 6rem;
}

.page-kicker,
.eyebrow {
  margin: 0 0 0.8rem;
  color: var(--accent-dark);
  font-size: 0.84rem;
  font-weight: 800;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.page-hero {
  padding-bottom: 2.8rem;
  border-bottom: 1px solid var(--line);
}

.page-hero h1 {
  max-width: 850px;
  margin: 0;
  color: var(--violet-950);
  font-family: Georgia, "Times New Roman", serif;
  font-size: clamp(2.55rem, 5vw, 4.6rem);
  font-weight: 500;
  letter-spacing: -0.035em;
  line-height: 1.04;
}

.page-hero > p:not(.page-kicker) {
  max-width: 760px;
  margin: 1.25rem 0 0;
  color: var(--muted);
  font-size: 1.23rem;
  line-height: 1.65;
}

.content-section {
  padding: 4.2rem 0;
  border-bottom: 1px solid var(--line);
  scroll-margin-top: calc(var(--header-height) + 24px);
}

.content-section:last-child {
  border-bottom: 0;
}

.content-section h2 {
  margin: 0 0 1.1rem;
  color: var(--violet-900);
  font-family: Georgia, "Times New Roman", serif;
  font-size: clamp(2rem, 3vw, 3rem);
  font-weight: 500;
  letter-spacing: -0.025em;
  line-height: 1.15;
}

.content-section h3 {
  margin: 2rem 0 0.6rem;
  color: var(--violet-800);
  font-size: 1.2rem;
  line-height: 1.4;
}

.content-section > p,
.prose-width {
  max-width: 790px;
}

.content-section ul,
.content-section ol {
  max-width: 820px;
  padding-left: 1.35rem;
}

.content-section li + li {
  margin-top: 0.5rem;
}

.lede {
  color: #514d63;
  font-size: 1.13rem;
}

.button-row {
  display: flex;
  margin-top: 1.8rem;
  gap: 0.8rem;
  flex-wrap: wrap;
}

.button {
  display: inline-flex;
  min-height: 46px;
  padding: 0.65rem 1.05rem;
  gap: 0.45rem;
  color: var(--white);
  background: var(--accent-dark);
  border: 1px solid var(--accent-dark);
  border-radius: 8px;
  align-items: center;
  font-weight: 700;
  text-decoration: none;
  transition: transform 150ms ease, box-shadow 150ms ease, background 150ms ease;
}

.button:hover {
  color: var(--white);
  background: var(--violet-700);
  box-shadow: 0 8px 20px rgba(76, 53, 141, 0.2);
  transform: translateY(-1px);
}

.button.secondary {
  color: var(--accent-dark);
  background: transparent;
}

.button.secondary:hover {
  color: var(--violet-900);
  background: var(--wash);
}

.home-hero {
  position: relative;
  min-height: 570px;
  padding: 5rem max(3.5rem, calc((100vw - 1560px) / 2)) 4.5rem;
  overflow: hidden;
  color: var(--white);
  background:
    radial-gradient(circle at 15% 20%, rgba(135, 111, 207, 0.52), transparent 28rem),
    radial-gradient(circle at 84% 42%, rgba(82, 151, 201, 0.25), transparent 31rem),
    linear-gradient(120deg, #1d1239 0%, #2d1d59 49%, #202d58 100%);
}

.home-hero::before {
  position: absolute;
  inset: 0;
  content: "";
  opacity: 0.3;
  background-image:
    radial-gradient(circle, rgba(255, 255, 255, 0.75) 0 1px, transparent 1.4px),
    radial-gradient(circle, rgba(139, 203, 230, 0.8) 0 1px, transparent 1.6px);
  background-position: 0 0, 52px 27px;
  background-size: 115px 92px, 147px 121px;
  -webkit-mask-image: linear-gradient(90deg, #000, transparent 72%);
  mask-image: linear-gradient(90deg, #000, transparent 72%);
}

.home-hero-inner {
  position: relative;
  z-index: 1;
  display: grid;
  width: min(100%, 1220px);
  margin-inline: auto;
  gap: 3rem;
  grid-template-columns: minmax(0, 1.05fr) minmax(420px, 0.95fr);
  align-items: center;
}

.home-hero-copy {
  max-width: 760px;
}

.home-hero .eyebrow {
  color: var(--blue-300);
}

.home-hero h1 {
  margin: 0;
  color: var(--white);
  font-family: Georgia, "Times New Roman", serif;
  font-size: clamp(2.45rem, 4.2vw, 4rem);
  font-weight: 700;
  letter-spacing: -0.036em;
  line-height: 1.08;
}

.home-subheader {
  margin: 1.25rem 0 0;
  color: #d9d5ef;
  font-size: clamp(1.12rem, 1.4vw, 1.35rem);
  font-weight: 600;
  line-height: 1.4;
  white-space: nowrap;
}

.home-lede {
  max-width: 690px;
  margin: 1.25rem 0 0;
  color: rgba(255, 255, 255, 0.76);
  font-size: 1.08rem;
  line-height: 1.7;
}

.home-hero .button {
  color: var(--violet-950);
  background: var(--white);
  border-color: var(--white);
}

.home-hero .button:hover {
  color: var(--violet-950);
  background: #f1edff;
}

.home-hero .button.secondary {
  color: var(--white);
  background: rgba(255, 255, 255, 0.06);
  border-color: rgba(255, 255, 255, 0.48);
}

.likelihood-card {
  position: relative;
  min-height: 450px;
  padding: 1.1rem;
  background: linear-gradient(160deg, rgba(255, 255, 255, 0.11), rgba(255, 255, 255, 0.025));
  border: 1px solid rgba(255, 255, 255, 0.16);
  border-radius: 22px;
  box-shadow: 0 28px 70px rgba(8, 4, 28, 0.34);
  backdrop-filter: blur(7px);
}

.likelihood-card svg {
  width: 100%;
  height: auto;
}

.plot-title {
  position: absolute;
  right: 1.35rem;
  bottom: 1rem;
  left: 1.35rem;
  display: flex;
  color: rgba(255, 255, 255, 0.68);
  align-items: center;
  justify-content: space-between;
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.plot-title span:last-child {
  color: var(--blue-300);
}

.home-content {
  width: min(100% - 64px, 1050px);
  margin-inline: auto;
  padding-bottom: 5rem;
}

.fact-grid,
.card-grid,
.link-grid,
.experiment-grid {
  display: grid;
  margin-top: 2rem;
  gap: 1rem;
}

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

.card-grid,
.link-grid {
  grid-template-columns: repeat(2, 1fr);
}

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

.fact,
.card,
.link-card,
.experiment {
  padding: 1.45rem;
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: 12px;
  box-shadow: var(--shadow-card);
}

.fact-number {
  display: block;
  color: var(--accent-dark);
  font-family: Georgia, "Times New Roman", serif;
  font-size: 2rem;
  line-height: 1;
}

.fact-label {
  display: block;
  margin-top: 0.55rem;
  color: var(--muted);
  font-size: 0.9rem;
}

.card h3,
.link-card h3,
.experiment h3 {
  margin: 0 0 0.5rem;
}

.card p,
.link-card p,
.experiment p {
  margin: 0;
  color: var(--muted);
  font-size: 0.95rem;
}

.link-card {
  display: block;
  color: inherit;
  text-decoration: none;
  transition: border-color 160ms ease, transform 160ms ease, box-shadow 160ms ease;
}

.link-card:hover {
  color: inherit;
  border-color: rgba(100, 75, 172, 0.5);
  box-shadow: var(--shadow-soft);
  transform: translateY(-2px);
}

.link-card .link-label {
  display: inline-block;
  margin-top: 1rem;
  color: var(--accent-dark);
  font-weight: 750;
}

.platform-guide-grid {
  align-items: stretch;
}

.platform-guide-card {
  position: relative;
  display: flex;
  min-height: 245px;
  padding: 0;
  overflow: hidden;
  flex-direction: column;
}

.platform-guide-card > svg {
  position: absolute;
  right: 1.35rem;
  bottom: 1.65rem;
}

.platform-logo {
  display: grid;
  min-height: 105px;
  padding: 1rem 1.25rem;
  background: #fff;
  border-bottom: 1px solid var(--line);
  place-items: center;
}

.platform-logo img {
  width: 100%;
  height: 72px;
  object-fit: contain;
}

.platform-logo.compact-logo img {
  height: 92px;
}

.platform-guide-copy {
  display: flex;
  padding: 1.3rem 1.45rem 1.45rem;
  flex: 1;
  flex-direction: column;
}

.platform-guide-copy h3 {
  margin-top: 0;
}

.platform-guide-copy .link-label {
  margin-top: auto;
  padding-top: 1rem;
}

.platform-guide-card.no-platform-logo {
  position: relative;
  min-height: 245px;
  background:
    linear-gradient(135deg, rgba(117, 88, 197, 0.08), rgba(91, 168, 209, 0.08)),
    var(--white);
}

.platform-guide-card.no-platform-logo::before {
  display: block;
  height: 5px;
  content: "";
  background: linear-gradient(90deg, var(--accent), var(--blue-500));
}

.experiment {
  position: relative;
  overflow: hidden;
}

.experiment::before {
  position: absolute;
  top: 0;
  right: 0;
  left: 0;
  height: 4px;
  content: "";
  background: linear-gradient(90deg, var(--accent), var(--blue-500));
}

.callout {
  max-width: 850px;
  margin-top: 1.8rem;
  padding: 1.3rem 1.45rem;
  background: linear-gradient(100deg, rgba(103, 80, 177, 0.1), rgba(91, 168, 209, 0.08));
  border: 1px solid rgba(103, 80, 177, 0.18);
  border-left: 4px solid var(--accent);
  border-radius: 0 10px 10px 0;
}

.callout > :first-child {
  margin-top: 0;
}

.callout > :last-child {
  margin-bottom: 0;
}

.steps {
  display: grid;
  margin: 2rem 0 0;
  padding: 0;
  gap: 1rem;
  list-style: none;
  counter-reset: steps;
}

.steps li {
  position: relative;
  min-height: 58px;
  margin: 0;
  padding: 0.25rem 0 0.25rem 4.4rem;
  counter-increment: steps;
}

.steps li::before {
  position: absolute;
  top: 0;
  left: 0;
  display: grid;
  width: 48px;
  height: 48px;
  color: var(--white);
  content: counter(steps, decimal-leading-zero);
  background: var(--accent-dark);
  border-radius: 50%;
  place-items: center;
  font-size: 0.8rem;
  font-weight: 800;
}

pre {
  max-width: 900px;
  padding: 1.25rem 1.4rem;
  overflow-x: auto;
  color: #ebe8fa;
  background: var(--violet-950);
  border: 1px solid #35285a;
  border-radius: 10px;
  box-shadow: var(--shadow-card);
  font: 0.9rem/1.65 ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
}

code {
  padding: 0.1em 0.28em;
  color: #4f3b8e;
  background: #f0edf8;
  border-radius: 4px;
  font: 0.9em ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
}

pre code {
  padding: 0;
  color: inherit;
  background: transparent;
  border-radius: 0;
}

.table-wrap {
  margin-top: 1.5rem;
  overflow-x: auto;
  border: 1px solid var(--line);
  border-radius: 10px;
}

table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.96rem;
}

th,
td {
  padding: 0.9rem 1rem;
  border-bottom: 1px solid var(--line);
  text-align: left;
  vertical-align: top;
}

th {
  color: var(--violet-800);
  background: var(--wash);
  font-size: 0.8rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

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

.tag {
  display: inline-flex;
  padding: 0.23rem 0.58rem;
  color: var(--accent-dark);
  background: rgba(117, 88, 197, 0.1);
  border: 1px solid rgba(117, 88, 197, 0.2);
  border-radius: 999px;
  align-items: center;
  font-size: 0.76rem;
  font-weight: 750;
  letter-spacing: 0.03em;
}

.site-footer {
  color: rgba(255, 255, 255, 0.72);
  background: var(--violet-950);
}

.footer-inner,
.footer-meta {
  display: flex;
  width: min(100% - 48px, 1300px);
  margin-inline: auto;
  justify-content: space-between;
}

.footer-inner {
  padding: 3rem 0;
  gap: 2rem;
  align-items: flex-start;
}

.footer-inner p {
  margin: 0;
}

.footer-name {
  color: var(--white);
  font-family: Georgia, "Times New Roman", serif;
  font-size: 1.8rem;
  font-weight: 700;
}

.footer-inner nav {
  display: flex;
  gap: 1.5rem;
  flex-wrap: wrap;
}

.footer-inner a {
  display: inline-flex;
  gap: 0.25rem;
  color: var(--white);
  align-items: center;
  font-weight: 650;
}

.footer-meta {
  padding: 1.1rem 0 1.4rem;
  gap: 1.5rem;
  border-top: 1px solid rgba(255, 255, 255, 0.12);
  font-size: 0.82rem;
}

.footer-meta p {
  margin: 0;
}

@media (max-width: 1360px) {
  .brand {
    width: 300px;
    min-width: 250px;
  }

  .brand-name {
    font-size: 1.72rem;
  }

  .brand-descriptor {
    font-size: 0.59rem;
  }

  .primary-navigation > a {
    padding-inline: 0.72rem;
    font-size: 0.92rem;
  }

  .primary-navigation .source-link {
    margin-left: 0.45rem;
    padding-inline: 0.75rem;
  }
}

@media (max-width: 1100px) {
  :root {
    --header-height: 76px;
    --side-width: 235px;
  }

  .header-inner {
    width: min(100% - 28px, 1540px);
  }

  .brand {
    width: 238px;
    min-width: 210px;
    padding-right: 1rem;
  }

  .brand-wordmark {
    font-size: 0.8rem;
    letter-spacing: 0.035em;
  }

  .primary-navigation > a {
    padding-inline: 0.5rem;
    font-size: 0.82rem;
  }

  .primary-navigation .source-link {
    margin: 1rem 0 1rem 0.3rem;
    padding-inline: 0.6rem;
  }

  .section-navigation a {
    font-size: 0.95rem;
  }

  .home-hero {
    padding-inline: 2.5rem;
  }

  .home-hero-inner {
    gap: 1.5rem;
    grid-template-columns: minmax(0, 1fr) minmax(350px, 0.78fr);
  }
}

@media (max-width: 900px) {
  :root {
    --header-height: 74px;
  }

  body.menu-open {
    overflow: hidden;
  }

  .brand::after {
    display: none;
  }

  .nav-toggle {
    display: inline-flex;
    min-width: 82px;
    margin-left: auto;
    padding: 0 0.7rem;
    gap: 0.4rem;
    color: var(--white);
    background: transparent;
    border: 0;
    align-items: center;
    justify-content: center;
    font-weight: 750;
  }

  .nav-toggle svg {
    width: 24px;
    height: 24px;
    fill: none;
    stroke: currentColor;
    stroke-linecap: round;
    stroke-width: 2;
  }

  .primary-navigation {
    position: fixed;
    top: var(--header-height);
    right: 0;
    bottom: 0;
    left: 0;
    display: none;
    padding: 1.2rem;
    overflow-y: auto;
    background: rgba(24, 16, 48, 0.98);
    flex-direction: column;
    align-items: stretch;
    justify-content: flex-start;
  }

  .primary-navigation.is-open {
    display: flex;
  }

  .primary-navigation > a {
    min-height: 58px;
    padding: 0.7rem 1rem;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    justify-content: flex-start;
    font-size: 1.08rem;
  }

  .primary-navigation > a::after {
    top: 15%;
    right: auto;
    bottom: 15%;
    left: 0;
    width: 4px;
    height: auto;
    border-radius: 0 4px 4px 0;
    transform: scaleY(0);
  }

  .primary-navigation > a:hover::after,
  .primary-navigation > a[aria-current="page"]::after {
    transform: scaleY(1);
  }

  .primary-navigation .source-link {
    margin: 1.2rem 0 0;
    color: var(--violet-950);
    background: var(--white);
    border-bottom: 0;
    justify-content: center;
  }

  .site-layout {
    display: block;
  }

  .section-navigation {
    position: sticky;
    z-index: 50;
    top: var(--header-height);
    border-right: 0;
    border-bottom: 1px solid var(--line);
  }

  .section-nav-inner {
    position: static;
    display: flex;
    max-height: none;
    padding: 0.7rem 1rem;
    overflow-x: auto;
    scrollbar-width: thin;
    align-items: center;
  }

  .section-nav-title {
    min-width: max-content;
    margin: 0 0.8rem 0 0;
  }

  .section-navigation nav {
    display: flex;
    min-width: max-content;
    gap: 0.35rem;
  }

  .section-navigation a {
    min-height: 38px;
    padding: 0.45rem 0.75rem;
    border: 1px solid transparent;
    border-radius: 999px;
    font-size: 0.9rem;
  }

  .section-navigation a:hover,
  .section-navigation a.is-active {
    border-color: rgba(104, 83, 177, 0.24);
  }

  .section-navigation svg {
    display: none;
  }

  .home-hero {
    padding: 4rem 2rem;
  }

  .home-hero-inner {
    grid-template-columns: 1fr;
  }

  .likelihood-card {
    width: min(100%, 610px);
    min-height: auto;
  }

  .fact-grid,
  .experiment-grid {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 640px) {
  body {
    font-size: 16px;
  }

  .header-inner {
    width: calc(100% - 20px);
  }

  .brand {
    width: 205px;
    min-width: 175px;
  }

  .brand-wordmark {
    font-size: 0.72rem;
    letter-spacing: 0.02em;
  }

  .nav-toggle {
    min-width: 48px;
    padding: 0;
  }

  .nav-toggle > span:last-child {
    position: absolute;
    width: 1px;
    height: 1px;
    overflow: hidden;
    clip: rect(0 0 0 0);
  }

  .home-hero {
    padding: 3.2rem 1.25rem;
  }

  .home-hero h1 {
    font-size: clamp(2.15rem, 11vw, 3rem);
  }

  .home-subheader {
    font-size: 1.08rem;
    white-space: normal;
  }

  .likelihood-card {
    padding: 0.4rem;
    border-radius: 14px;
  }

  .plot-title {
    position: static;
    padding: 0 0.7rem 0.55rem;
    gap: 0.5rem;
    font-size: 0.67rem;
  }

  .home-content,
  .content-wrap {
    width: min(100% - 32px, 1050px);
  }

  .content-wrap {
    padding-top: 3rem;
  }

  .page-hero h1 {
    font-size: clamp(2.25rem, 12vw, 3.4rem);
  }

  .page-hero > p:not(.page-kicker) {
    font-size: 1.08rem;
  }

  .content-section {
    padding: 3.2rem 0;
  }

  .fact-grid,
  .card-grid,
  .link-grid,
  .experiment-grid {
    grid-template-columns: 1fr;
  }

  .footer-inner,
  .footer-meta {
    width: min(100% - 32px, 1300px);
    flex-direction: column;
  }

  .footer-inner nav {
    gap: 1rem;
  }

  .footer-meta {
    gap: 0.4rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    transition-duration: 0.01ms !important;
  }
}

@media print {
  .site-header,
  .section-navigation,
  .site-footer,
  .button-row {
    display: none !important;
  }

  .site-layout {
    display: block;
  }

  .content-wrap,
  .home-content {
    width: 100%;
  }
}