:root {
  color-scheme: dark;
  --bg: #0b0d10;
  --surface: #11151a;
  --surface-2: #171c22;
  --text: #f0ede6;
  --muted: #9ca4ad;
  --faint: #69727c;
  --line: #272e36;
  --line-strong: #3a444f;
  --accent: #d5ff5f;
  --accent-soft: rgba(213, 255, 95, 0.12);
  --max: 1240px;
  --serif: Georgia, "Times New Roman", serif;
  --sans: Inter, ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --mono: "SFMono-Regular", Consolas, "Liberation Mono", monospace;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

a { color: inherit; }
a:focus-visible { outline: 2px solid var(--accent); outline-offset: 4px; }

.skip-link {
  position: fixed;
  left: 16px;
  top: -100px;
  z-index: 10;
  background: var(--accent);
  color: #0b0d10;
  padding: 10px 14px;
  font-weight: 700;
  text-decoration: none;
}
.skip-link:focus { top: 16px; }

.site-header {
  width: min(calc(100% - 48px), var(--max));
  margin: 0 auto;
  min-height: 88px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-bottom: 1px solid var(--line);
}

.wordmark {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  color: var(--text);
  font-weight: 700;
  letter-spacing: -0.02em;
  text-decoration: none;
}
.wordmark-mark {
  display: grid;
  place-items: center;
  width: 42px;
  height: 42px;
  border: 1px solid var(--line-strong);
  font: 700 12px/1 var(--mono);
  letter-spacing: 0.02em;
  color: var(--accent);
}

nav { display: flex; gap: 28px; }
nav a {
  color: var(--muted);
  font-size: 14px;
  text-decoration: none;
  transition: color 160ms ease;
}
nav a:hover { color: var(--text); }

.hero,
.section,
footer {
  width: min(calc(100% - 48px), var(--max));
  margin-inline: auto;
}

.hero {
  padding: 112px 0 88px;
}
.eyebrow,
.section-kicker,
.note-id,
.problem-id,
.status {
  font: 600 12px/1.4 var(--mono);
  letter-spacing: 0.08em;
  text-transform: uppercase;
}
.eyebrow,
.section-kicker,
.note-id,
.problem-id { color: var(--accent); }

.hero h1 {
  max-width: 980px;
  margin: 24px 0 26px;
  font-family: var(--serif);
  font-size: clamp(60px, 9vw, 132px);
  font-weight: 400;
  line-height: 0.91;
  letter-spacing: -0.055em;
}
.hero-copy {
  max-width: 760px;
  margin: 0;
  color: var(--muted);
  font-size: clamp(21px, 2.5vw, 30px);
  line-height: 1.35;
  letter-spacing: -0.02em;
}
.hero-actions { display: flex; gap: 12px; margin-top: 38px; flex-wrap: wrap; }
.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 0 18px;
  border: 1px solid var(--line-strong);
  font-size: 14px;
  font-weight: 700;
  text-decoration: none;
}
.button-primary { background: var(--accent); color: #0b0d10; border-color: var(--accent); }
.button-secondary:hover { background: var(--surface); }
.hero-rule { height: 1px; background: var(--line); margin: 84px 0 34px; }
.thesis {
  max-width: 1000px;
  margin: 0;
  font-family: var(--serif);
  font-size: clamp(26px, 3vw, 42px);
  line-height: 1.25;
  letter-spacing: -0.025em;
}

.section {
  padding: 104px 0;
  border-top: 1px solid var(--line);
}
.section-heading {
  display: grid;
  grid-template-columns: minmax(150px, 0.6fr) minmax(300px, 2fr) minmax(260px, 1fr);
  gap: 36px;
  align-items: start;
  margin-bottom: 58px;
}
.section-heading h2 {
  margin: 0;
  font-family: var(--serif);
  font-size: clamp(38px, 5vw, 68px);
  font-weight: 400;
  line-height: 1.02;
  letter-spacing: -0.04em;
}
.section-heading > p:last-child {
  margin: 0;
  color: var(--muted);
}
.section-kicker { margin: 9px 0 0; }

.program-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}
.program-card {
  position: relative;
  min-height: 620px;
  padding: 30px;
  border-right: 1px solid var(--line);
  background: linear-gradient(180deg, transparent, rgba(255,255,255,0.015));
}
.program-card:last-child { border-right: 0; }
.program-number { color: var(--faint); font: 500 12px/1 var(--mono); }
.status { margin: 74px 0 24px; color: var(--muted); }
.status-dot {
  display: inline-block;
  width: 7px;
  height: 7px;
  margin-right: 8px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 0 4px var(--accent-soft);
}
.program-card h3 {
  margin: 0 0 22px;
  font-family: var(--serif);
  font-size: 33px;
  line-height: 1.05;
  font-weight: 400;
  letter-spacing: -0.03em;
}
.program-question {
  color: var(--text);
  font-size: 18px;
  line-height: 1.45;
}
.program-card > p:not(.status):not(.program-question) { color: var(--muted); }
.tag-list {
  position: absolute;
  left: 30px;
  right: 30px;
  bottom: 30px;
  display: flex;
  gap: 7px;
  flex-wrap: wrap;
  list-style: none;
  margin: 0;
  padding: 0;
}
.tag-list li,
.program-pill {
  border: 1px solid var(--line-strong);
  padding: 6px 9px;
  color: var(--muted);
  font: 500 11px/1.2 var(--mono);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.split-section {
  display: grid;
  grid-template-columns: 0.8fr 1.7fr;
  gap: 76px;
}
.split-section .section-heading { display: block; margin: 0; }
.split-section .section-heading h2 { margin: 18px 0 24px; }
.sticky-heading { align-self: start; position: sticky; top: 36px; }
.notes-list { border-top: 1px solid var(--line); }
.note-row {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 24px;
  padding: 32px 0;
  border-bottom: 1px solid var(--line);
  text-decoration: none;
}
.note-row h3 { margin: 8px 0 6px; font-size: 25px; letter-spacing: -0.025em; }
.note-row p { margin: 0; color: var(--muted); }
.note-meta {
  display: flex;
  gap: 18px;
  align-items: start;
  color: var(--faint);
  font: 500 11px/1.4 var(--mono);
  text-transform: uppercase;
}
.note-row:hover h3 { color: var(--accent); }
.empty-state { padding: 30px 0; color: var(--muted); }
.empty-state p { margin: 0; max-width: 700px; }
.empty-state strong { color: var(--text); }

.problem-list { border-top: 1px solid var(--line); }
.problem {
  display: grid;
  grid-template-columns: 100px 1fr auto;
  gap: 30px;
  align-items: start;
  padding: 34px 0;
  border-bottom: 1px solid var(--line);
}
.problem h3 { margin: 0 0 9px; font-size: 23px; letter-spacing: -0.02em; }
.problem p { max-width: 780px; margin: 0; color: var(--muted); }
.program-pill { white-space: nowrap; }

.operating-model .section-heading { grid-template-columns: 0.6fr 2fr; }
.principles-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  border: 1px solid var(--line);
}
.principles-grid article { min-height: 300px; padding: 28px; border-right: 1px solid var(--line); }
.principles-grid article:last-child { border-right: 0; }
.principles-grid span { color: var(--faint); font: 500 12px/1 var(--mono); }
.principles-grid h3 { margin: 72px 0 14px; font-family: var(--serif); font-size: 25px; font-weight: 400; line-height: 1.1; }
.principles-grid p { margin: 0; color: var(--muted); }

.about-section {
  display: grid;
  grid-template-columns: 0.85fr 1.3fr;
  gap: 90px;
}
.about-section h2 {
  margin: 18px 0 0;
  font-family: var(--serif);
  font-size: clamp(42px, 5vw, 68px);
  line-height: 1.02;
  font-weight: 400;
  letter-spacing: -0.04em;
}
.about-copy { font-size: 19px; }
.about-copy p { margin-top: 0; margin-bottom: 24px; }
.about-copy p:not(.collaboration) { color: var(--muted); }
.collaboration { margin-top: 42px; padding-top: 28px; border-top: 1px solid var(--line); }
.collaboration a { color: var(--accent); text-underline-offset: 3px; }

footer {
  display: grid;
  grid-template-columns: 1fr 1.5fr auto;
  gap: 40px;
  align-items: center;
  padding: 46px 0 64px;
  border-top: 1px solid var(--line);
  color: var(--faint);
  font-size: 13px;
}
.footer-mark { color: var(--muted); }
footer p { margin: 0; }

/* Research note */
.note-page .site-header { margin-bottom: 0; }
.note-article {
  width: min(calc(100% - 48px), 880px);
  margin: 0 auto;
  padding: 100px 0 120px;
}
.note-article .note-id { display: block; margin-bottom: 18px; }
.note-article h1 {
  margin: 0 0 24px;
  font-family: var(--serif);
  font-size: clamp(52px, 8vw, 88px);
  font-weight: 400;
  line-height: .95;
  letter-spacing: -0.05em;
}
.note-deck { font-size: 24px; color: var(--muted); line-height: 1.4; }
.note-byline {
  display: flex;
  gap: 20px;
  margin: 32px 0 62px;
  padding-bottom: 28px;
  border-bottom: 1px solid var(--line);
  color: var(--faint);
  font: 500 11px/1.4 var(--mono);
  text-transform: uppercase;
}
.note-article h2 { margin: 58px 0 18px; font-family: var(--serif); font-size: 36px; font-weight: 400; letter-spacing: -0.03em; }
.note-article p, .note-article li { font-size: 18px; color: #c7ccd1; }
.note-article strong { color: var(--text); }
.note-article blockquote {
  margin: 46px 0;
  padding: 2px 0 2px 28px;
  border-left: 2px solid var(--accent);
  font-family: var(--serif);
  font-size: 30px;
  line-height: 1.25;
}
.note-article blockquote p { margin: 0; color: var(--text); font: inherit; }
.note-back { display: inline-block; margin-top: 64px; color: var(--accent); text-decoration: none; font-weight: 700; }

@media (max-width: 900px) {
  .site-header { min-height: 74px; }
  nav { display: none; }
  .hero { padding-top: 80px; }
  .section-heading { grid-template-columns: 1fr; gap: 18px; }
  .section-kicker { margin: 0; }
  .program-grid { grid-template-columns: 1fr; }
  .program-card { min-height: auto; padding-bottom: 110px; border-right: 0; border-bottom: 1px solid var(--line); }
  .program-card:last-child { border-bottom: 0; }
  .status { margin-top: 42px; }
  .split-section { grid-template-columns: 1fr; gap: 48px; }
  .sticky-heading { position: static; }
  .principles-grid { grid-template-columns: 1fr 1fr; }
  .principles-grid article:nth-child(2) { border-right: 0; }
  .principles-grid article:nth-child(-n+2) { border-bottom: 1px solid var(--line); }
  .about-section { grid-template-columns: 1fr; gap: 42px; }
  footer { grid-template-columns: 1fr; }
}

@media (max-width: 620px) {
  .site-header, .hero, .section, footer { width: min(calc(100% - 32px), var(--max)); }
  .hero { padding: 68px 0 64px; }
  .hero h1 { font-size: clamp(54px, 17vw, 84px); }
  .hero-rule { margin-top: 64px; }
  .section { padding: 76px 0; }
  .problem { grid-template-columns: 1fr; gap: 10px; }
  .program-pill { justify-self: start; margin-top: 6px; }
  .note-row { grid-template-columns: 1fr; }
  .note-meta { flex-wrap: wrap; }
  .principles-grid { grid-template-columns: 1fr; }
  .principles-grid article { min-height: auto; border-right: 0; border-bottom: 1px solid var(--line); }
  .principles-grid article:last-child { border-bottom: 0; }
  .principles-grid h3 { margin-top: 46px; }
  .note-article { width: min(calc(100% - 32px), 880px); padding-top: 70px; }
  .note-byline { flex-wrap: wrap; }
}