:root {
  --bg: #fafafa;
  --card: #ffffff;
  --text: #151515;
  --muted: #6d6d6d;
  --line: #e8e8e8;
  --accent: #2457d6;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  line-height: 1.65;
}

a { color: inherit; }

.wrap {
  width: min(880px, calc(100% - 40px));
  margin: 0 auto;
}

nav {
  height: 72px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-bottom: 1px solid var(--line);
}

.brand {
  text-decoration: none;
  font-weight: 700;
  letter-spacing: -0.02em;
}

.nav-link {
  text-decoration: none;
  color: var(--muted);
  font-size: 0.92rem;
}

.nav-link:hover,
.nav-link.active {
  color: var(--text);
}

.hero {
  padding: 96px 0 72px;
}

.paper-hero {
  padding-bottom: 56px;
}

.kicker {
  margin: 0 0 14px;
  color: var(--accent);
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

h1 {
  margin: 0;
  font-size: clamp(4rem, 12vw, 7.5rem);
  line-height: 0.92;
  letter-spacing: -0.07em;
  font-weight: 700;
}

.summary {
  max-width: 720px;
  margin: 28px 0 0;
  color: #2b2b2b;
  font-size: clamp(1.2rem, 2.2vw, 1.55rem);
  line-height: 1.5;
  letter-spacing: -0.02em;
}

.meta {
  display: flex;
  flex-wrap: wrap;
  gap: 42px;
  margin-top: 42px;
}

.meta > div,
.paper-meta > div {
  display: grid;
  gap: 3px;
}

.meta span,
.paper-meta span {
  color: var(--muted);
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.meta strong,
.paper-meta strong {
  font-size: 0.95rem;
  font-weight: 600;
}

.content {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 18px;
  padding-bottom: 26px;
}

.content.single {
  grid-template-columns: 1fr;
}

.content > div,
.paper-meta {
  padding: 28px;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 14px;
}

h2 {
  margin: 0 0 12px;
  font-size: 1.05rem;
  letter-spacing: -0.02em;
}

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

.text-link {
  display: inline-block;
  margin-top: 16px;
  color: var(--accent);
  text-decoration: none;
  font-weight: 600;
  font-size: 0.92rem;
}

.text-link:hover { text-decoration: underline; }

.paper-meta {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

footer {
  min-height: 88px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 0.82rem;
}

footer .text-link {
  margin-top: 0;
}

@media (max-width: 680px) {
  .wrap { width: min(100% - 24px, 880px); }

  .hero { padding: 72px 0 54px; }

  .content,
  .paper-meta {
    grid-template-columns: 1fr;
  }

  .meta {
    flex-direction: column;
    gap: 18px;
  }

  footer {
    align-items: flex-start;
    flex-direction: column;
    justify-content: center;
    padding: 22px 0;
  }
}