:root {
  --paper: #faf8f3;
  --paper-deep: #f3efe7;
  --ink: rgba(42, 44, 56, 0.94);
  --muted: rgba(42, 44, 56, 0.68);
  --line: rgba(42, 44, 56, 0.12);
  --line-strong: rgba(42, 44, 56, 0.24);
  --accent: rgba(42, 44, 56, 0.88);
  --accent-soft: rgba(42, 44, 56, 0.06);
  --panel: rgba(255, 252, 247, 0.72);
  --panel-strong: rgba(255, 255, 255, 0.9);
  --shadow: 0 12px 26px rgba(42, 44, 56, 0.08);
  --heading: "IBM Plex Sans", sans-serif;
  --body: "IBM Plex Sans", sans-serif;
  --mono: "JetBrains Mono", monospace;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

html,
body {
  margin: 0;
  min-height: 100%;
}

body {
  font-family: var(--body);
  color: var(--ink);
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.7), rgba(250, 248, 243, 0.94)),
    linear-gradient(180deg, var(--paper) 0%, var(--paper-deep) 100%);
  overflow-x: hidden;
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  background-image:
    linear-gradient(rgba(42, 44, 56, 0.04) 1px, transparent 1px),
    linear-gradient(90deg, rgba(42, 44, 56, 0.04) 1px, transparent 1px),
    linear-gradient(rgba(42, 44, 56, 0.09) 1px, transparent 1px),
    linear-gradient(90deg, rgba(42, 44, 56, 0.09) 1px, transparent 1px);
  background-size: 33px 33px, 33px 33px, 132px 132px, 132px 132px;
  background-position: 0 0, 0 0, 0 0, 0 0;
}

a {
  color: var(--ink);
  text-decoration-thickness: 1px;
  text-underline-offset: 0.16em;
}

.site-shell,
.page-shell {
  width: min(1220px, calc(100vw - 30px));
  margin: 18px auto 56px;
}

.site-header {
  position: sticky;
  top: 14px;
  z-index: 30;
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: 18px;
  padding: 16px 18px;
  border: 1px solid var(--line);
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.92), rgba(250, 248, 243, 0.9));
  backdrop-filter: blur(18px);
  box-shadow: var(--shadow);
}

.brand,
.header-link {
  text-decoration: none;
}

.brand {
  display: inline-grid;
  gap: 3px;
  color: var(--ink);
}

.brand-name {
  font-family: var(--mono);
  font-size: 0.98rem;
  font-weight: 600;
  letter-spacing: 0.02em;
}

.site-nav {
  display: flex;
  justify-content: center;
  gap: 16px;
  flex-wrap: wrap;
}

.site-nav a {
  color: var(--muted);
  text-decoration: none;
  font-family: var(--mono);
  font-size: 0.74rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

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

.header-link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 42px;
  padding: 0 14px;
  border: 1px solid var(--line-strong);
  background: var(--panel);
  color: var(--ink);
  font-family: var(--mono);
  font-size: 0.74rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.site-main {
  display: grid;
  gap: 48px;
  margin-top: 32px;
}

.hero-frame,
.section-panel,
.feature-card,
.research-card,
.list-card,
.overview-card {
  border: 0;
  background: transparent;
  box-shadow: none;
}

.hero-frame {
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.38), rgba(255, 255, 255, 0.08)),
    linear-gradient(rgba(42, 44, 56, 0.025) 1px, transparent 1px),
    linear-gradient(90deg, rgba(42, 44, 56, 0.025) 1px, transparent 1px);
  background-size: auto, 26px 26px, 26px 26px;
}

.frame-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  padding: 12px 18px;
  border-bottom: 1px solid var(--line);
  color: var(--muted);
  font-family: var(--mono);
  font-size: 0.7rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.35fr) minmax(300px, 0.78fr);
  gap: 40px;
  padding: 30px 0;
}

.eyebrow,
.section-tag,
.card-label,
.meta,
.section-index,
.section-title {
  color: var(--ink);
  font-family: var(--mono);
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

h1,
h2,
h3 {
  margin: 0;
  font-family: var(--heading);
  color: var(--ink);
}

h1 {
  margin-top: 12px;
  font-size: clamp(1.9rem, 4.1vw, 2.7rem);
  line-height: 1.08;
  letter-spacing: -0.04em;
}

h2 {
  font-size: clamp(1.42rem, 2.2vw, 1.9rem);
  line-height: 1.1;
  letter-spacing: -0.03em;
}

h3 {
  font-size: 1.03rem;
  line-height: 1.34;
  letter-spacing: -0.02em;
}

.feature-card h3,
.research-card h3,
.list-card h3,
.signal-card h2 {
  margin-top: 10px;
}

.hero-text,
.research-card p,
.list-card p,
.overview-card p,
.detail-list li {
  color: var(--muted);
  line-height: 1.9;
}

.hero-text {
  max-width: 62ch;
  margin: 16px 0 0;
  font-size: 0.98rem;
}

.hero-actions {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  margin-top: 28px;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 46px;
  padding: 0 16px;
  border: 1px solid var(--line-strong);
  background: rgba(255, 255, 255, 0.74);
  text-decoration: none;
  font-family: var(--mono);
  font-size: 0.74rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  transition:
    transform 160ms ease,
    background 160ms ease,
    color 160ms ease;
}

.button:hover {
  transform: translateY(-1px);
}

.button.primary {
  background: var(--accent);
  border-color: var(--accent);
  color: var(--paper);
}

.button.secondary {
  background: rgba(255, 255, 255, 0.56);
  color: var(--ink);
}

.hero-side {
  position: relative;
  display: grid;
  gap: 18px;
}

.hero-position-card {
  margin-top: 18px;
}

.signal-card {
  position: relative;
  z-index: 1;
  padding: 18px 0 0;
  border: 0;
  border-top: 1px solid var(--line);
  background: transparent;
}

.signal-card p,
.signal-card a {
  margin: 0;
  display: block;
}

.signal-card p + p,
.signal-card a + a,
.signal-card h2 + p {
  margin-top: 8px;
}

.sketch-card {
  min-height: 210px;
  overflow: hidden;
  background:
    linear-gradient(rgba(42, 44, 56, 0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(42, 44, 56, 0.05) 1px, transparent 1px),
    rgba(255, 255, 255, 0.54);
  background-size: 24px 24px;
}

.node,
.edge {
  position: absolute;
}

.node {
  width: 12px;
  height: 12px;
  background: var(--ink);
  border-radius: 2px;
}

.node.n1 { top: 34px; left: 36px; }
.node.n2 { top: 76px; left: 138px; }
.node.n3 { top: 42px; right: 52px; }
.node.n4 { bottom: 52px; left: 82px; }
.node.n5 {
  bottom: 40px;
  right: 88px;
  width: 18px;
  height: 18px;
  background: transparent;
  border: 3px solid var(--ink);
  border-radius: 999px;
}

.edge {
  height: 1px;
  transform-origin: left center;
  background: rgba(42, 44, 56, 0.3);
}

.edge.e1 { top: 40px; left: 42px; width: 110px; transform: rotate(21deg); }
.edge.e2 { top: 82px; left: 145px; width: 106px; transform: rotate(-19deg); }
.edge.e3 { bottom: 54px; left: 89px; width: 146px; transform: rotate(-7deg); }
.edge.e4 { top: 48px; left: 44px; width: 84px; transform: rotate(70deg); }

.atlas-section {
  display: grid;
  grid-template-columns: 140px 1fr;
  gap: 40px;
  align-items: start;
}

.section-rail {
  position: sticky;
  top: 96px;
  display: grid;
  gap: 8px;
  padding-top: 16px;
}

.section-index {
  color: var(--muted);
}

.section-title {
  color: var(--ink);
}

.section-panel {
  padding: 0;
}

.research-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 24px;
}

.feature-grid,
.two-column-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 24px;
}

.three-column-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 24px;
}

.feature-card,
.research-card,
.list-card,
.overview-card {
  padding: 24px 0 0;
  background: transparent;
  border-top: 1px solid var(--line);
}

.research-card-link {
  display: grid;
  grid-template-columns: 180px minmax(0, 1fr) auto;
  align-items: start;
  gap: 22px;
  color: inherit;
  text-decoration: none;
  transition:
    transform 160ms ease,
    border-color 160ms ease,
    color 160ms ease;
}

.research-card-link:hover {
  transform: translateX(4px);
  border-color: var(--line-strong);
}

.research-card-link h3,
.research-card-link p {
  text-decoration: none;
}

.research-card-link .card-label {
  margin-top: 2px;
}

.research-card-link h3 {
  margin-top: 0;
}

.research-card-link > p:last-of-type {
  margin: 0;
}

.card-open {
  display: inline-flex;
  align-self: start;
  margin-top: 2px;
  color: var(--ink);
  font-family: var(--mono);
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.feature-actions {
  margin-top: 24px;
}

.activity-stack {
  display: grid;
  gap: 18px;
  margin-top: 20px;
}

.activity-block + .activity-block {
  padding-top: 18px;
  border-top: 1px solid var(--line);
}

.activity-title {
  margin: 0 0 8px;
  color: var(--ink);
  font-size: 0.93rem;
  font-weight: 600;
  line-height: 1.58;
}

.activity-block p:last-child {
  margin: 0;
  color: var(--muted);
  line-height: 1.84;
}

.overview-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

.accent-card {
  background:
    transparent;
}

.mini-list,
.detail-list {
  margin: 18px 0 0;
  padding-left: 1.1rem;
}

.detail-list.compact {
  margin-top: 0;
}

.detail-list li + li {
  margin-top: 14px;
}

.muted,
.muted-inline {
  color: var(--muted);
}

.muted-inline {
  font-size: 0.82rem;
}

.list-note {
  margin-top: 10px;
}

.sublabel {
  margin-top: 20px;
}

@media (max-width: 1080px) {
  .hero-grid,
  .overview-grid,
  .feature-grid,
  .two-column-grid,
  .three-column-grid {
    grid-template-columns: 1fr;
  }

  .research-card-link {
    grid-template-columns: 1fr;
    gap: 10px;
  }
}

@media (max-width: 860px) {
  .site-header {
    grid-template-columns: 1fr;
    justify-items: start;
  }

  .site-nav {
    justify-content: start;
  }

  .atlas-section {
    grid-template-columns: 1fr;
  }

  .section-rail {
    position: static;
    padding-top: 0;
  }

  .hero-grid,
  .section-panel {
    padding: 0;
  }
}

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

  .button {
    transition: none;
  }
}