:root {
  --paper: #f7f6f1;
  --ink: #1d2724;
  --muted: #5f6964;
  --accent: #874b37;
  --line: rgba(29, 39, 36, 0.17);
  --soft: #ecece6;
  --serif: "Newsreader", Georgia, serif;
  --sans: "DM Sans", Arial, sans-serif;
  --page: 930px;
}

* { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
  scroll-padding-top: 86px;
}

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 18px;
  line-height: 1.72;
  text-rendering: optimizeLegibility;
}

a { color: inherit; }

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

.skip-link {
  position: absolute;
  left: -9999px;
  top: 10px;
  z-index: 1000;
  padding: 10px 14px;
  background: var(--ink);
  color: white;
}

.skip-link:focus { left: 10px; }

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0,0,0,0);
  white-space: nowrap;
  border: 0;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(247, 246, 241, 0.94);
  border-bottom: 1px solid transparent;
  backdrop-filter: blur(12px);
}

.site-header.scrolled { border-color: var(--line); }

.nav-wrap {
  min-height: 76px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 28px;
}

.brand {
  display: flex;
  flex-direction: column;
  line-height: 1.08;
  text-decoration: none;
}

.brand-name {
  font-family: var(--serif);
  font-size: 24px;
  font-weight: 500;
}

.brand-company {
  margin-top: 5px;
  color: var(--muted);
  font-size: 10px;
  font-weight: 600;
  letter-spacing: .14em;
  text-transform: uppercase;
}

.site-nav {
  display: flex;
  gap: 25px;
}

.site-nav a {
  color: var(--muted);
  font-size: 13px;
  font-weight: 600;
  text-decoration: none;
}

.site-nav a:hover { color: var(--accent); }

.menu-button {
  display: none;
  width: 42px;
  height: 42px;
  border: 0;
  background: transparent;
}

.menu-button span:not(.sr-only) {
  display: block;
  width: 24px;
  height: 2px;
  margin: 5px auto;
  background: var(--ink);
}

.essay {
  max-width: var(--page);
}

.opening {
  padding: 88px 0 110px;
}

.byline,
.chapter-label,
.case-role {
  margin: 0 0 18px;
  color: var(--accent);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: .13em;
  text-transform: uppercase;
}

h1,
h2,
h3 {
  margin-top: 0;
  font-family: var(--serif);
  font-weight: 400;
  line-height: 1.12;
}

h1 {
  max-width: 740px;
  margin-bottom: 46px;
  font-size: clamp(48px, 5vw, 61px);
  letter-spacing: -.018em;
}

h2 {
  max-width: 780px;
  margin-bottom: 30px;
  font-size: clamp(39px, 4.2vw, 47px);
  letter-spacing: -.014em;
}

h3 {
  margin-bottom: 13px;
  font-size: 31px;
}

.opening-copy,
.prose,
.chapter-intro {
  max-width: 740px;
}

.opening-copy {
  color: var(--muted);
  font-family: var(--serif);
  font-size: clamp(19px, 1.8vw, 21px);
  line-height: 1.5;
}

.opening-copy p { margin: 0 0 21px; }

.signature-line {
  color: var(--ink);
  font-weight: 500;
}

.opening-link {
  margin-top: 34px;
}

.opening-link a,
.case-body a,
.about-link a {
  font-size: 14px;
  font-weight: 600;
  text-underline-offset: 5px;
}

.about-link {
  margin-top: 8px;
}

.chapter {
  padding: 92px 0;
  border-top: 1px solid var(--line);
}

.prose,
.chapter-intro,
.case-body {
  color: var(--muted);
}

.prose {
  font-size: 18px;
}

.prose p:first-child,
.case-body p:first-child {
  margin-top: 0;
}

.chapter-intro {
  margin: 0 0 48px;
  font-size: 19px;
}

.contribution-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  column-gap: 60px;
}

.contribution-grid article {
  padding: 28px 0 8px;
  border-top: 1px solid var(--line);
}

.number {
  margin: 0 0 39px;
  color: var(--accent);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: .12em;
}

.contribution-grid article > p:last-child {
  margin-bottom: 0;
  color: var(--muted);
  font-size: 15px;
}

.case-study {
  display: grid;
  grid-template-columns: .72fr 1.28fr;
  gap: 70px;
  padding: 58px 0 8px;
  margin-top: 54px;
  border-top: 1px solid var(--line);
}

.case-study + .case-study {
  margin-top: 58px;
}

.case-study h3 {
  margin-bottom: 6px;
  font-size: 38px;
}

.case-subtitle {
  margin: 0;
  color: var(--muted);
  font-family: var(--serif);
  font-size: 18px;
  line-height: 1.35;
}

.case-body {
  font-size: 16px;
}

.question-list {
  margin-top: 44px;
  border-top: 1px solid var(--line);
}

.question-list p {
  margin: 0;
  padding: 24px 0;
  border-bottom: 1px solid var(--line);
  font-family: var(--serif);
  font-size: clamp(19px, 2vw, 23px);
  line-height: 1.4;
}

.about .prose p:first-child {
  color: var(--ink);
  font-size: 20px;
}

.closing {
  padding: 105px 0 100px;
  border-top: 1px solid var(--line);
}

.closing-main,
.closing-emphasis {
  max-width: 850px;
  margin: 0;
  font-family: var(--serif);
  font-size: clamp(32px, 3.6vw, 40px);
  line-height: 1.22;
}

.closing-emphasis {
  color: var(--accent);
}

.closing-contact {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 40px;
  align-items: end;
  margin-top: 58px;
  padding-top: 28px;
  border-top: 1px solid var(--line);
}

.closing-contact p {
  max-width: 590px;
  margin: 0;
  color: var(--muted);
}

.closing-contact a {
  font-family: var(--serif);
  font-size: 29px;
  font-weight: 500;
  text-underline-offset: 6px;
}

.site-footer {
  padding: 24px 0;
  border-top: 1px solid var(--line);
}

.footer-wrap {
  display: flex;
  justify-content: space-between;
  gap: 20px;
  color: var(--muted);
  font-size: 12px;
}

.footer-wrap p { margin: 0; }
.footer-wrap a { text-decoration: none; }

@media (max-width: 760px) {
  .menu-button { display: block; }

  .site-nav {
    display: none;
    position: absolute;
    top: 76px;
    left: 0;
    width: 100%;
    padding: 24px 20px 30px;
    flex-direction: column;
    align-items: flex-start;
    background: var(--paper);
    border-bottom: 1px solid var(--line);
  }

  .site-nav.open { display: flex; }

  .case-study {
    grid-template-columns: 1fr;
    gap: 28px;
  }

  .closing-contact {
    grid-template-columns: 1fr;
    align-items: start;
  }
}

@media (max-width: 620px) {
  body {
    font-size: 17px;
  }

  .page {
    width: min(calc(100% - 28px), var(--page));
  }

  .opening {
    padding: 58px 0 78px;
  }

  h1 {
    font-size: 40px;
    line-height: 1.08;
    margin-bottom: 34px;
  }

  h2 {
    font-size: 34px;
  }

  h3 {
    font-size: 27px;
  }

  .opening-copy {
    font-size: 19px;
  }

  .chapter {
    padding: 72px 0;
  }

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

  .question-list p {
    font-size: 20px;
  }

  .closing-main,
  .closing-emphasis {
    font-size: 30px;
  }

  .closing-contact a {
    font-size: 25px;
    overflow-wrap: anywhere;
  }

  .footer-wrap {
    flex-direction: column;
  }
}