:root {
  --bg: radial-gradient(circle at 15% 20%, #fef7ea, #f0ecff 44%, #e7f3ff);
  --card-bg: rgba(255, 255, 255, 0.88);
  --ink: #10253a;
  --muted: #425a73;
  --accent: #ff6f61;
  --line: #dce4f1;
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  padding: 0;
}

body {
  background: var(--bg);
  color: var(--ink);
  font-family: "Avenir Next", "Trebuchet MS", "Segoe UI", sans-serif;
  min-height: 100vh;
}

.shell {
  width: min(1100px, calc(100% - 3rem));
  margin: 0 auto;
}

.site-header {
  padding: 1.2rem 0;
  position: sticky;
  top: 0;
  backdrop-filter: blur(6px);
  z-index: 10;
}

.site-header .shell {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.brand {
  text-decoration: none;
  color: var(--ink);
  letter-spacing: 0.04em;
  font-weight: 700;
  font-size: 1.1rem;
}

.social-link {
  text-decoration: none;
  color: var(--muted);
  font-size: 0.95rem;
  border: 1px solid rgba(18, 39, 65, 0.22);
  border-radius: 999px;
  padding: 0.32rem 0.6rem;
  white-space: nowrap;
}

.site-header .social-link:hover {
  border-color: rgba(18, 39, 65, 0.45);
  color: var(--ink);
}

nav {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
}

nav a,
.topic-card a,
#documents a,
.card a {
  text-decoration: none;
  color: #25476c;
}

main {
  display: grid;
  gap: 1rem;
  padding-bottom: 3rem;
}

.card {
  background: var(--card-bg);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 1.1rem;
  animation: fadeUp 280ms ease;
}

.hero h1 {
  margin: 0.25rem 0;
  font-size: clamp(1.4rem, 2vw, 2.1rem);
}

.eyebrow {
  margin: 0;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  font-size: 0.78rem;
}

#graph-wrap {
  border-radius: 12px;
  border: 1px dashed #c9d9ee;
  min-height: 420px;
  position: relative;
  overflow: hidden;
  background:
    radial-gradient(circle at 18% 12%, rgba(255, 255, 255, 0.75), transparent 28%),
    radial-gradient(circle at 75% 70%, rgba(255, 221, 204, 0.45), transparent 35%),
    transparent;
}

#graph {
  width: 100%;
  height: min(460px, 70vh);
  display: block;
}

#graph text {
  font-size: 12px;
  text-anchor: middle;
  fill: var(--ink);
}

.section-head p {
  margin-top: 0;
  color: var(--muted);
}

.topic-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 1rem;
}

.topic-card {
  border: 1px solid #d7e1f1;
  border-radius: 12px;
  padding: 0.8rem;
  background: #f7fbff;
}

.topic-card h3 {
  margin-top: 0.2rem;
}

ul {
  margin: 0.4rem 0;
  padding-left: 1.2rem;
}

.site-footer {
  margin: 1.6rem 0 2rem;
  text-align: center;
  color: #496482;
}

.document-page aside {
  display: flex;
  gap: 0.8rem;
  flex-wrap: wrap;
  margin: 1rem 0;
}

a.btn {
  background: #111f35;
  color: #fff;
  border-radius: 999px;
  padding: 0.5rem 0.9rem;
  font-size: 0.92rem;
  text-decoration: none;
}

a.btn.secondary {
  background: transparent;
  color: #112b46;
  border: 1px solid #a5b8d2;
}

.doc-meta {
  color: #4d6280;
  font-size: 0.92rem;
}

@media (max-width: 700px) {
  .shell {
    width: min(1100px, calc(100% - 1.2rem));
  }
}

@keyframes fadeUp {
  from {
    transform: translateY(6px);
    opacity: 0;
  }

  to {
    transform: translateY(0);
    opacity: 1;
  }
}