:root {
  --bg: #fbfbfa;
  --ink: #0c0c0c;
  --muted: #656560;
  --line: #dcdcd7;
  --line-strong: #b9b9b3;
  --soft: #f1f1ee;
  --paper: #ffffff;
  --max: 1180px;
  --serif: "Fraunces", "Iowan Old Style", "Palatino Linotype", serif;
  --sans: "Inter", Arial, Helvetica, sans-serif;
  --mono: "IBM Plex Mono", "SFMono-Regular", Menlo, Consolas, monospace;
  color-scheme: light;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: 96px;
}

body {
  margin: 0;
  background:
    radial-gradient(closest-side, transparent 0 60%, var(--bg) 100%),
    linear-gradient(180deg, var(--paper) 0%, var(--bg) 620px, var(--bg) 100%);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.55;
  letter-spacing: 0;
  -webkit-font-smoothing: antialiased;
}

/* faint concentric contour rings, standing in for the grid: an ambient
   nod to corneal topography maps, held to pure grayscale */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: -1;
  background-image:
    repeating-radial-gradient(
      circle at 86% 8%,
      rgba(12, 12, 12, 0.05) 0px,
      rgba(12, 12, 12, 0.05) 1px,
      transparent 1px,
      transparent 46px
    );
  mask-image: radial-gradient(circle at 86% 8%, rgba(0,0,0,.9) 0%, transparent 62%);
}

a {
  color: inherit;
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
  text-underline-offset: 0.28em;
}

button,
input,
textarea {
  font: inherit;
}

:focus-visible {
  outline: 2px solid var(--ink);
  outline-offset: 3px;
  border-radius: 50%;
}

.skip-link {
  position: fixed;
  left: 16px;
  top: 12px;
  transform: translateY(-160%);
  background: var(--ink);
  color: var(--paper);
  padding: 8px 12px;
  z-index: 20;
}

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

/* ---------- header ---------- */

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 14px clamp(24px, 5vw, 66px);
  border-bottom: 1px solid var(--line);
  background: rgba(251, 251, 250, 0.86);
  backdrop-filter: blur(16px);
}

.header-left {
  display: flex;
  align-items: center;
  gap: 14px;
}

/* the identity mark carries the page's one recurring signature: a
   Landolt ring, the broken circle used on every visual-acuity chart.
   the gap points at "SN" the way an optotype points at an answer. */
.identity-mark {
  position: relative;
  width: 44px;
  height: 44px;
  border: 0;
  border-radius: 50%;
  background: transparent;
  color: var(--ink);
  display: grid;
  place-items: center;
  cursor: pointer;
}

.identity-mark svg {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  transform: rotate(38deg);
  transition: transform 420ms cubic-bezier(.2,.8,.2,1);
}

.identity-mark span {
  position: relative;
  font-family: var(--mono);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.02em;
}

.identity-mark:hover svg,
.identity-mark:focus-visible svg {
  transform: rotate(218deg);
}

.scroll-dial {
  width: 22px;
  height: 22px;
  flex: none;
  opacity: 0.55;
}

.scroll-dial svg {
  width: 100%;
  height: 100%;
  transform: rotate(0deg);
  transition: transform 60ms linear;
}

.site-nav {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 8px 22px;
  color: var(--muted);
  font-family: var(--mono);
  font-size: 11px;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.09em;
}

.site-nav a {
  transition: color 180ms ease;
}

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

main {
  width: min(var(--max), calc(100% - 96px));
  margin: 0 auto;
}

.section-panel {
  border-bottom: 1px solid var(--line);
  padding: clamp(58px, 10vw, 132px) 0;
}

/* ---------- hero ---------- */

.hero {
  position: relative;
  min-height: calc(100svh - 73px);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  gap: 60px;
  overflow: clip;
}

.hero-watermark {
  position: absolute;
  right: clamp(-140px, -6vw, -40px);
  top: clamp(-60px, -4vw, 10px);
  width: clamp(320px, 42vw, 620px);
  height: clamp(320px, 42vw, 620px);
  color: var(--ink);
  opacity: 0.05;
  pointer-events: none;
  animation: drift 90s linear infinite;
}

.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(280px, 0.52fr);
  align-items: end;
  gap: clamp(28px, 7vw, 92px);
}

.eyebrow,
.entry-time,
.chapter-head span,
.subhead,
.form-note {
  color: var(--muted);
  font-family: var(--mono);
  font-size: 11px;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.1em;
}

.hero h1 {
  grid-column: 1 / -1;
  margin: 0;
  font-family: var(--serif);
  font-optical-sizing: auto;
  font-size: clamp(72px, 18vw, 224px);
  line-height: 0.86;
  letter-spacing: -0.01em;
  font-weight: 600;
  filter: blur(14px);
  opacity: 0;
  transform: translateY(10px) scale(1.01);
  animation: focus-in 1100ms 120ms cubic-bezier(.2,.7,.2,1) forwards;
}

.hero-copy {
  grid-column: 2;
  max-width: 520px;
}

.role {
  margin: 0 0 22px;
  font-family: var(--serif);
  font-size: clamp(23px, 3.4vw, 42px);
  line-height: 1.08;
  font-weight: 500;
  font-style: italic;
}

.intro {
  margin: 0;
  color: var(--muted);
  font-size: clamp(16px, 1.6vw, 18px);
}

.index-band {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.index-band a {
  border: 1px solid var(--line);
  padding: 8px 11px;
  background: rgba(255, 255, 255, 0.5);
  font-family: var(--mono);
  font-size: 11px;
  font-weight: 500;
}

.index-band {
  position: relative;
  padding: 18px 0;
  border-bottom: 1px solid var(--line);
}

.index-band a {
  transition: border-color 180ms ease, background 180ms ease;
}

.index-band a:hover {
  border-color: var(--ink);
  background: var(--paper);
  text-decoration: none;
}

/* ---------- chapters ---------- */

.chapter {
  display: grid;
  grid-template-columns: 260px minmax(0, 1fr);
  gap: clamp(28px, 6vw, 86px);
}

.chapter-head {
  position: sticky;
  top: 102px;
  align-self: start;
}

.chapter-head h2 {
  margin: 8px 0 0;
  font-family: var(--serif);
  font-size: clamp(22px, 2.6vw, 40px);
  line-height: 1.02;
  font-weight: 600;
  letter-spacing: 0.01em;
  max-width: 100%;
  overflow-wrap: break-word;
  word-break: break-word;
  hyphens: auto;
  filter: blur(7px);
  opacity: 0;
  transform: translateY(14px);
  transition: filter 620ms cubic-bezier(.2,.7,.2,1), opacity 620ms ease, transform 620ms cubic-bezier(.2,.7,.2,1);
}

.chapter-head.is-focused h2 {
  filter: blur(0);
  opacity: 1;
  transform: translateY(0);
}

.chapter-head.small h2 {
  font-size: clamp(18px, 2vw, 28px);
}

.timeline,
.publication-list,
.column-list,
.definition-list {
  margin: 0;
}

.entry {
  display: grid;
  grid-template-columns: 150px minmax(0, 1fr);
  gap: 26px;
  padding: 24px 0;
  border-top: 1px solid var(--line);
}

.entry:first-child,
.compact {
  padding-top: 0;
  border-top: 0;
}

.entry h3,
.list-grid h3 {
  margin: 0 0 6px;
  font-family: var(--serif);
  font-size: clamp(18px, 2vw, 22px);
  font-weight: 600;
  line-height: 1.15;
}

.entry p,
.list-grid p {
  margin: 0;
  color: var(--muted);
}

.detail {
  margin-top: 10px !important;
}

ul {
  margin: 14px 0 0;
  padding-left: 18px;
  color: var(--muted);
}

.list-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  border-top: 1px solid var(--line);
}

.list-grid article {
  min-height: 150px;
  padding: 22px;
  border-right: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  transition: background 200ms ease;
}

.list-grid article:hover {
  background: var(--soft);
}

.list-grid article:nth-child(2n) {
  border-right: 0;
}

.list-grid.dense article {
  min-height: 126px;
}

.publication-intro {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 28px;
  margin-bottom: 38px;
}

.publication-intro--solo {
  justify-content: flex-end;
}

.publication-intro p {
  max-width: 660px;
  margin: 0;
  font-family: var(--serif);
  font-size: clamp(19px, 2vw, 26px);
  font-style: italic;
  line-height: 1.22;
}

.text-button,
.idea-form button {
  border: 1px solid var(--ink);
  background: var(--ink);
  color: var(--paper);
  padding: 12px 16px;
  cursor: pointer;
  font-family: var(--mono);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.03em;
  transition: background 180ms ease, color 180ms ease, transform 180ms ease;
}

.text-button:hover,
.idea-form button:hover {
  background: transparent;
  color: var(--ink);
  transform: translateY(-1px);
}

.subhead {
  margin: 32px 0 14px;
}

.publication-list {
  padding-left: 22px;
}

.publication-list li {
  padding: 12px 0;
  border-top: 1px solid var(--line);
}

.long-list:not(.is-expanded) li:nth-child(n+4) {
  display: none;
}

.column-list {
  columns: 2;
  column-gap: 48px;
  padding-left: 18px;
}

.column-list li {
  break-inside: avoid;
  padding: 0 0 14px;
  color: var(--muted);
}

.definition-list {
  border-top: 1px solid var(--line);
}

.definition-list div {
  display: grid;
  grid-template-columns: 130px 1fr;
  gap: 18px;
  padding: 16px 0;
  border-bottom: 1px solid var(--line);
}

dt {
  font-family: var(--mono);
  font-weight: 600;
  font-size: 13px;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

dd {
  margin: 0;
  color: var(--muted);
}

/* ---------- contact ---------- */

.contact-grid {
  display: grid;
  grid-template-columns: minmax(220px, 0.55fr) minmax(280px, 1fr);
  gap: clamp(32px, 6vw, 76px);
}

.contact-line {
  margin: 0 0 12px;
  font-family: var(--sans);
  font-size: 15px;
  line-height: 1.3;
  font-weight: 500;
}

.contact-line a {
  display: inline-flex;
  align-items: center;
  gap: 9px;
}

.contact-icon {
  width: 18px;
  height: 18px;
  flex: none;
  color: var(--ink);
  border-radius: 50%;
  transition: transform 220ms cubic-bezier(.2,.8,.2,1), background 220ms ease, color 220ms ease;
}

.contact-line a:hover .contact-icon,
.contact-line a:focus-visible .contact-icon {
  background: var(--ink);
  color: var(--paper);
  transform: rotate(-10deg) scale(1.05);
}

.contact-line a:hover,
.contact-line a:focus-visible {
  text-decoration: none;
}

.contact-line a:hover span,
.contact-line a:focus-visible span {
  text-decoration: underline;
  text-underline-offset: 0.28em;
}

.idea-form {
  display: grid;
  gap: 16px;
}

.idea-form label {
  display: grid;
  gap: 8px;
}

.idea-form span {
  color: var(--muted);
  font-family: var(--mono);
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
}

.idea-form input,
.idea-form textarea {
  width: 100%;
  border: 1px solid var(--line);
  background: var(--paper);
  color: var(--ink);
  padding: 13px 14px;
  outline: none;
  resize: vertical;
}

.idea-form input:focus,
.idea-form textarea:focus {
  border-color: var(--ink);
  border-radius: 0;
}

.idea-form button {
  justify-self: start;
}

.form-note {
  margin: 0;
  text-transform: none;
  letter-spacing: 0;
  font-weight: 500;
  font-size: 12px;
}

.site-footer {
  width: min(var(--max), calc(100% - 96px));
  margin: 0 auto;
  padding: 26px 0 42px;
  display: flex;
  justify-content: space-between;
  color: var(--muted);
  font-family: var(--mono);
  font-size: 11px;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.1em;
}

@keyframes focus-in {
  from {
    filter: blur(14px);
    opacity: 0;
    transform: translateY(10px) scale(1.01);
  }
  to {
    filter: blur(0);
    opacity: 1;
    transform: translateY(0) scale(1);
  }
}

@keyframes drift {
  from { transform: rotate(0deg); }
  to { transform: rotate(360deg); }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }

  .hero h1,
  .chapter-head h2 {
    filter: blur(0) !important;
    opacity: 1 !important;
    transform: none !important;
  }
}

@media (max-width: 900px) {
  .site-header {
    align-items: flex-start;
  }

  .site-nav {
    max-width: 560px;
  }

  .hero-grid,
  .chapter,
  .contact-grid {
    grid-template-columns: 1fr;
  }

  .hero-copy {
    grid-column: 1;
  }

  .chapter-head {
    position: static;
  }

  .publication-intro {
    align-items: start;
    flex-direction: column;
  }

  .column-list {
    columns: 1;
  }
}

@media (max-width: 680px) {
  main,
  .site-footer {
    width: min(100% - 48px, var(--max));
  }

  .site-header {
    padding: 12px 24px;
  }

  .site-nav {
    gap: 7px 12px;
    font-size: 9px;
  }

  .scroll-dial {
    display: none;
  }

  .identity-mark {
    width: 38px;
    height: 38px;
  }

  .hero {
    min-height: calc(100svh - 86px);
  }

  .hero h1 {
    font-size: clamp(64px, 24vw, 112px);
  }

  .hero-watermark {
    width: 60vw;
    height: 60vw;
    opacity: 0.04;
  }

  .entry {
    grid-template-columns: 1fr;
    gap: 8px;
  }

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

  .list-grid article,
  .list-grid article:nth-child(2n) {
    border-right: 0;
  }

  .definition-list div {
    grid-template-columns: 1fr;
    gap: 3px;
  }

  .contact-line {
    overflow-wrap: anywhere;
  }
}