:root {
  --bg: #f4f1ea;
  --ink: #12161c;
  --mute: #5c6570;
  --line: #d7d1c6;
  --x: #0f4c5c;
  --pad: clamp(20px, 7vw, 96px);
}

* { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; }

body {
  min-height: 100vh;
  color: var(--ink);
  background:
    linear-gradient(180deg, rgba(15, 76, 92, 0.04), transparent 28%),
    var(--bg);
  font-family: "Source Serif 4", "Iowan Old Style", "Songti SC", "STSong", Georgia, serif;
  line-height: 1.65;
}

.top, main, footer { position: relative; }

.top {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 24px;
  padding: 28px var(--pad) 22px;
  border-bottom: 1px solid var(--line);
}

.mark {
  text-decoration: none;
  color: var(--ink);
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.mark-word {
  font-family: ui-monospace, "IBM Plex Mono", Menlo, monospace;
  font-size: 15px;
  letter-spacing: 0.42em;
  font-weight: 600;
}

.mark-full {
  font-size: 12px;
  letter-spacing: 0.08em;
  color: var(--x);
}

nav { display: flex; gap: 22px; flex-wrap: wrap; }

nav a {
  color: var(--mute);
  text-decoration: none;
  font-size: 14px;
}

nav a:hover { color: var(--x); }

.hero {
  padding: 72px var(--pad) 56px;
  max-width: 52rem;
}

.kicker {
  font-family: ui-monospace, Menlo, monospace;
  font-size: 11px;
  letter-spacing: 0.22em;
  color: var(--x);
  margin-bottom: 22px;
}

h1 {
  font-size: clamp(32px, 5vw, 56px);
  line-height: 1.18;
  font-weight: 600;
  letter-spacing: -0.02em;
}

.lede {
  margin-top: 24px;
  font-size: 18px;
  color: var(--mute);
  max-width: 40rem;
}

.lede strong { color: var(--ink); font-weight: 600; }
.lede em { font-style: normal; color: var(--x); }
.lede.compact { margin-top: 0; }

.band {
  margin: 0 var(--pad);
  padding: 36px 0 8px;
  border-top: 1px solid var(--line);
}

.eq {
  font-family: ui-monospace, Menlo, monospace;
  font-size: clamp(22px, 3vw, 32px);
  letter-spacing: 0.08em;
  margin-bottom: 36px;
  color: var(--ink);
}

.eq .x {
  color: var(--x);
  border-bottom: 2px solid var(--x);
  padding: 0 4px;
}

.eq .op { color: var(--mute); margin: 0 10px; }

.expand {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 28px 40px;
}

.expand dt {
  font-family: ui-monospace, Menlo, monospace;
  font-size: 12px;
  letter-spacing: 0.14em;
  color: var(--x);
  margin-bottom: 8px;
}

.expand dd { color: var(--mute); font-size: 16px; }

.section { padding: 64px var(--pad); }

.section-head { margin-bottom: 28px; max-width: 40rem; }

.label {
  font-family: ui-monospace, Menlo, monospace;
  font-size: 11px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--x);
  margin-bottom: 10px;
}

h2 { font-size: clamp(24px, 3vw, 34px); font-weight: 600; }

.split {
  display: grid;
  grid-template-columns: 1.3fr 0.9fr;
  gap: 40px;
  align-items: start;
}

.split > p { color: var(--mute); font-size: 17px; }

.facts {
  list-style: none;
  border: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.45);
}

.facts li {
  display: grid;
  grid-template-columns: 88px 1fr;
  gap: 12px;
  padding: 12px 16px;
  border-bottom: 1px solid var(--line);
  font-size: 15px;
}

.facts li:last-child { border-bottom: 0; }

.facts span {
  color: var(--mute);
  font-family: ui-monospace, Menlo, monospace;
  font-size: 11px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  padding-top: 4px;
}

.cards {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 20px;
}

.cards article {
  padding: 22px 20px 24px;
  border-top: 2px solid var(--ink);
}

.cards span {
  font-family: ui-monospace, Menlo, monospace;
  font-size: 12px;
  color: var(--x);
}

.cards h3 { margin: 14px 0 10px; font-size: 20px; }
.cards p { color: var(--mute); }

.mail a {
  font-family: ui-monospace, Menlo, monospace;
  font-size: 18px;
  color: var(--ink);
  text-decoration: none;
  border-bottom: 1px solid var(--ink);
}

.mail a:hover { color: var(--x); border-color: var(--x); }

footer {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
  padding: 28px var(--pad) 40px;
  border-top: 1px solid var(--line);
  color: var(--mute);
  font-size: 13px;
}

@media (max-width: 860px) {
  .expand, .split, .cards { grid-template-columns: 1fr; }
  .hero { padding-top: 48px; }
  nav { font-size: 13px; }
}